PRE2016 4 Groep1

Group Members

• Sjoerd van Helden 0893960
• Stijn Middelhuis 0947014
• Roy Niemark 0956824
• Andrei Pintilie 0980402
• Dennis Struver 0955477

Project definition

In this chapter the project is defined by elaborating the subject, goal, approach, objectives, deliverables and the project planning.

Subject

The safety of a child. For a parent, this is all that matters. But keeping their child safe all time is a very time-consuming job. Having to constantly watch the child and making sure the activity the child is performing is safe costs a lot of time and effort. The home is of importance when analyzing child injuries. It is the environment in which young children grow up in and achieve developmental milestones. A child’s injury risk within the home is a joint interaction between the parents, the child and the environment. Both unintentional and intentional injuries are of importance as the majority of infant/child homicides occur in the home. Most of the accidents under children take place at home. The most severe injuries are associated with heat-related accidents and fall from high places, so even if the most accidents were encountered in the living/dining room, the most serious ones happen in the kitchen and on the stairs. Regarding the falls, around 10 children die each year by this accident. But, mostly, children that fall from stairs or high places encounter trauma and possible some visible post-accident problems.

Technology has been making a lot of progress over the years and this will keep on going. Since there are a lot possible nowadays, more ideas can be realized. One of the new technologies that are growing fast is a SMART House system. A SMART House is becoming will be more well-known and will extend more as we go into the future. The concept that has been conceived is an extension to the concept of a SMART Home. This SMART home will not be focusing on solely on luxury or caregiving, but on enhancing the safety of children. This system will focus on preventing certain dangerous situations and reduce the accidents that occur at home. The concept will be installable in every house with the implementations that are relevant. ‘The house’ will then provide certain actions with the equipment that it has available to keep the children safer. The system needs to be able to detect where a person is in the house or in a room, but also recognize if it is a parent or a child. When it is able to do that, it also needs to be able to communicate with its other components that can prevent danger in the house, and take action when the child is approaching such a dangerous situation. When it is able to distinguish parents and children, the parents will not experience any obstruction from the system. Also, it does not need to take the same actions when the child is with a parent because this situation is a lot less dangerous.

The concept can be used for children of an age between 1 and 9 years old. In this age-category, children are most likely to have serious accidents at home. Also, children at that age are able to move around the house and interact with objects by itself but are not able to stay at home by themselves. The accidents and injuries that are going to be focused on reducing are injuries due to poisoning, falls and thermal injuries. The concept of this SMART Home will keep the child away from dangerous situations and/or objects, and when it is not able to take appropriate action it will alert the parents. For example, when the system detects that the child is near a sink with hot water, it shuts down the hot water so the child can not burn itself.

Goal

Since today's technology goes pretty far already, there is a lot possible considering a SMART Home. Yet when this needs to be adapted and be a perfect fit for your child's safety, some factors and aspects need to be researched and designed for this purpose. Our goal is to reduce accidents and injuries of children in their home by extending the concept of the SMART Home with respect to child safety while keeping the technological, ethical and financial aspects in mind. In this project, a specific part of a home will be addressed and a specific accident category will be targeted. To extend the concept of the SMART Home we will research and design the system needed for the part that is going to be addressed, evaluate this in detail and look at the concept and how this can be applied to other parts of the house. How this will be achieved will be explained in the Approach and Objectives.

Approach

To reach our goal it is necessary to gather specific and discrete information about frequent occurring accidents and injuries of children. Then such a SMART Home system with its focus on the safety of the child will be researched and the possibilities and the techniques will be exploited. Therefore, detection hardware systems that satisfy the requirements of this system will be analyzed and researched and the best option for this concept will be recommended. The requirements for this system and what the possibilities are will be elaborated further on in this project. Since the detection is the most important part of this system this needs to be viable in order to let the system work and will get the most attention. In this project, a part of such a SMART Home system will be addressed and elaborated. The focus will lie on one accident category and in the end of the project a specific part of the system will be designed and evaluated in detail. Finally, the designed part of the SMART Home system will be applied to more parts of the house. With example situations and simulations, the designed system for the specific part and other parts of the house will be evaluated. In this project, it is important to evaluate the impact of the system, to stay close to the users and user needs, to address USE-aspects and to keep in mind the cost and benefit. Thus when designing the system the users, cost, and benefit will receive a lot of attention and the final stage of the project will be dedicated to the evaluation with respect to impact, USE-aspect, and overall benefit.

Objectives

Following the approach and considering the goal of this project the following objectives can be derived:

O1: Gather information about frequent child accidents and injuries in the home.

To be able to implement a system that enhances the safety of children, it needs to be clear where the most accidents happen, what kind of accidents actually happen and how severe the injuries are. Then different situations can be considered and different safety issues can be targeted.

O2: Research the potential dangers, and potential prevention.

When the kind of accidents that happen frequently are known, we want to know how these can happen and how this can be prevented. When the potential dangers are known, it is important that the system is able to recognize these dangers or to know how it can reduce them. The dangers that have to be prevented need to be implemented into the system, and the action that belongs to preventing the danger also has to be implemented.

O3: Find the best option for detection and recognition.

To be able to distinguish an adult from a child, the system has to be able to recognize different subjects. The system will need to operate mostly when a child is alone or not supervised.

O4: Define and work out a specific accident category and situation in the house.

We want to narrow down the concept due to the time window that is available for this project. We will choose a specific situation and target a specific accident category that is of higher importance but also that will use a concept that is suitable for different situations as well.

O5: Design and evaluate the part of the system for the specifications determined in O4.

Consider all the important factors, such as user, ethics, and cost, to design a concept for the specific situation that will reduce a certain risk of an accident category. Take into account safety margins and user needs, but also possibilities for extensions.

O6: Simulate different situations to show usability, operating and impact of the concept.

When a concept is designed we will use simulations to visualize how it works and what it can do. Also, this will show extensions and possibilities.

Deliverables

In this project, the following things will be delivered at the end.

• Documentation of the research and literature study
• Preliminary design: Stairs (drawings)
• Scenario descriptions of the designed system for the stairs (visualization).
  • Gate
  • Sensors
  • Stairs
  • Child
• Evaluation of the system with respect to the impact, USE-aspects, and cost-benefit

Project planning

For a project, is important to have a good project planning. Below the planning for this project is given. The week planning and a role distribution are made to keep track of the progress and provide a guideline while working on this project. The planning follows the process and sets several milestones that are important to achieve. The planning is made at the begin of the project and has some room for adjustments, if necessary. In week 4 we made some changes to the project definition and narrowed down the subject. This had a significant impact on our planning and thus the planning is adjusted with the changed definition, to make sure the milestones are achieved properly with the time that is left.

During every week, the wiki should be updated with the progress made up until that point. The last week is dedicated to preparing for the final presentation and finalizing the wiki. The week planning below contains some more specific detail to the different steps that need to be taken in this project.

The general approach of this project consists of the following milestones (for more detail see the planning itself):

1. Research background, state of the art and similar existing systems
2. Research detection and recognition technologies with the respect to our subject
3. Draw conclusions and recommendations for the detection possibilities
4. Designing a part of the system focused on a specific situation
5. Evaluate the designed system with simulations and work out possible extensions or adjustments
6. Evaluate the cost, benefit, and impact of SMART Home system and the detection possibilities

Weekplanning

Week 1

• Determine the subject
  • Formulate the problem
  • Create idea’s for a concept
  • Objectives
  • Involved users
• Research about background, state of the art and similar existing systems
• Create planning and presentation

Week 2

• Continuing the research
  • Children and accidents
  • Existing SMART Homes and its collaboration with safety measures
  • Typical house environments for children
  • State of the art technology that could be implemented or used.
  • Existing systems made for safety of children
  • User benefit
• Determine important and critical points of interest
• Look into the subject from a USE perspective and determine relevant USE aspects

Week 3

• Finish the background research (Milestone 1)
• Start research about the detection possibilities
  • Existing technologies
  • Requirements and options for this project
  • How and what can be accomplished in our project with which technology
  • State-of-the-art options
• Conceptualize the subject to a specific and detailed design question (Milestone 2)
  • Composition of the room
  • Components (technological) which can be used
  • Elaboration of the design requirements

Adjusted planning for weeks 4 up until 9:

At the beginning of week 4, we decided to narrow down our project. Instead of looking at all possible dangers for children in a home and how to tackle them, we now only focus on one of the biggest causes of both fatal and non-fatal injuries, falls from the stairs. This means that we do not have to consider the whole house, but only the stairways and the halls towards the stairways. Therefore we have to change our planning. Here is the new planning for the following weeks:

Week 4

• Narrow down the subject and elaborate on the choices
  • Assumptions made
  • Determine the deliverables
  • What is taken into account and what is not?
  • Why are they taken into account or not?
• Research the possibilities of localization
  • Proximity detection between child and certain points
  • Badges/bracelets
  • Ultrasound
  • Infrared sensors
• Research the possibilities of person recognition/detection
  • Difference between a child and an adult

Week 5

• Research the necessary information for design a system
  • State of the art technology (for staircase gates)
  • Movement speed of the children
  • Closing speed of such a gate
  • Safety settings for the system in combination with the localization (safety margins to be sure the gate is closed in time)
  • System settings (specified to age and preference of the parents)
• Designing the system following the design question
  • Which localization and recognition/detection will be used?
  • What technical hardware will be implemented?
  • How will this be programmed and setup?
  • How will the system work?

Week 6

• • Finish the design for the specified purpose
  • Describe several scenarios
  • Pros and cons of the designed system
  • Possible extensions and settings
• Evaluated the design for the specified purpose
  • What can/will it do?
  • Possibilities and usability
  • Cost of this part of the system
• Application of this part in a SMART home system
  • Extension to a bigger system
  • Application of this system in other parts of the house

Week 7

• Work out the application in a whole house
  • Different options for localization/detection
  • System settings and extensions
• Evaluate the designed system
  • Benefit for the users
  • Impact from the perspective of USE

Week 8

• Accomplish recommendations and conclusion for designing such a system
• Elaborate on the different detection/recognition and localization possibilities and their pros and cons
• Elaborate and conclude the evaluation and impact of such a system

Week 9

• Finish, prepare and give the presentation
• Finish the wiki
  • Reorganize if necessary
  • Check the progress
  • Complete the final wiki page

USE-aspects SMART House

Users

The primary users of the system are the parents of the children and the children themselves. The parents are the one that will buy the system and have the system installed into their house. The parents will expect the system to help them protect their children and keep them safe. The children are the ones where the systems is designed for and are therefore also primary users. However, the children will barely know that the system is there. The secondary users of the system are older children, nannies and other people who visit the house. The secondary users will know that the system is there and will sometimes notice its actions, but will not be affected by it most of the time. When a secondary user is in the room with a child that is protected by the house, the actions of the system will be slightly different since the child is under supervision at that moment, even if that supervision is an adult visitor of the house.. The tertiary users are the technicians, mechanics and software engineers who make and implement the system. The technicians have to make sure that the system is easily installed, removed and also calibrated if necessary. They will also be the ones that conduct maintenance.

Society

Parenting can be stressful and there can be multiple reasons for that. Among those reasons are: time demands, relationship demands (related to time demands), protective instinct/uncertainty and a lack of alone time. Also the stress level for single parents is often higher when a single mother have to take care of their young children.

Stress is bad for the parents itself but it also affects the child negatively. Parental stress can lead to mental health problems (depression, anxiety, internalizing behavior) among children already at a young age and it negatively affects their externalizing behavior. Externalizing behavior is usually associated with multiple disorders like Antisocial Personality Disorder, Oppositional defiant disorder, pyromania among others. It has also been shown that parental fatigue can have a negative effect on a child but also affects parental practices .

The problems that result from parental stress and fatigue are detrimental for society. Children with mental health issues will need to get treated for that which cost money and time and it might never be fully healed. For example, the risk of recurrence after a first major depressive episode is 50% and increases with subsequent episodes (Post, 1992, Kupfer et al., 1996, American Psychiatric Association, 2000). Children with mental health problems will perform worse in school and other places than healthy children. If their mental health problems are never healed it will affect their adult lives as well. Parental fatigue might lead to bad parenting which also isn’t desirable.

This means that society benefits from a solution to parental stress and fatigue which our SMART home provides. The child safe SMART home can tackle the reasons mentioned in the beginning and help reduce parental fatigue. But also the child safe system can reduce the accidents which happen among young children. This reducement in the amount of injuries could positively affect the health statistics of society. Later on there will be a recapitulation about if this is achieved with the designed system.

However, a SMART home that protects a child from any kind of harm within the house can be negative for the child’s development and mental health. Multiple studies have shown that overprotective parenting affects the child’s mental health, anxiety disorder is the most common one. This wouldn’t be beneficial to society because this would impair a child’s productivity and quality of life. More recently the Dutch institution VeiligheidNL argued that parents should allow their children to take on more risks because that would be beneficial to their development. The potential benefits that a SMART home would have for society would be offset by these problems. Therefore should the child safety be implemented wisely in a SMART house system to avoid these problems.

Enterprise

Being able to stay in touch with your customers is the best outcome that a salesman can achieve. The business model for SMART houses is just at its beginning, which means that there is plenty of space for new developments and ideas that can create a strong bond between the users and the merchants. Even if there are few sectors that might suffer because of this newly created area, most of the actors in the project are going to benefit. As main enterprise actors can be included the retailers, companies that provide technology and the safety companies. In the vision of this project, a safe SMART house is intended to keep the children safe from most dangers that can occur with help of SMART systems.

But how exactly will enterprise profit by this new area of interests? First, it is necessary to be specified that the entrepreneurs will take a significant role in the safe SMART house area. They are going to provide the necessary technology and safety regulations. So, the next three points represent the main interests of the enterprise:

• Increased products sales
• Pay-as-you-go house services
• Providable research outcomes

The first point is stated as Increased hardware sales. A safe SMART house contains more than just ordinary hardware that has to be created. It needs SMART products which have been tested and do not represent a problem for most types of users. Also these products have to be able to implement in a SMART house. A product that shall be able to connect to the house facilities and integrate properly. As you can speculate, this means a lot of revenue from selling these items. A second point is represented by the pay-as-you-go house services. Besides the payment for the SMART technology that might occur, users shall be able to pay for their health and safety, which means that the retailers could improve the software of a machine to increase the safety level on the amount of money you are willing to pay. Also, new devices could be added later as you pay when you think you need them. The last point is represented by the research which still have to be done. Full functioning SMART houses are still in development and therefore research is necessary. This counts for the convenience part of a SMART house, but also for the child safety which is treated in this project. Research can result in new or better products which can be used outside the SMART house application. Enterprise benefits from this by putting new products on the market.

A SMART home would enable retailers to develop a close relationship with their clients through the SMART devices which are placed in the home. It means that in the case of a problem that occurs, retailers will be able to find a solution or to recommend new products directly to the customers. When maintenance is needed this can also be done quickly by making directly an appointment. The greatest achievement is represented by the possibility to seduce young people, “tech savvy consumers” and the fast possibility of ads presentation and close connection to the users.

The enterprise point of view of this project would not be much different than a normal SMART house. The addition of making it safe will involve some more actors like people that provide hardware tools for safety and software developers that need to develop more than just a self-aware house that can notify the user. It should also react and protect the kids. As an entrepreneur, everything related to this idea is reduced to money. On the other side of these new possibilities offered by this technology is the security aspect, both in physical and software ways. In the software ways, SMART houses are going to be the target of hackers, which can use the technology designed to keep you safe in wrong ways. That’s why the entrepreneurs have to invest a lot of money in secure software and invest even more when their products are hijacked. Besides the financial costs, the missing security in software can turn the population against the usage of such a technology.

Accidents Statistics

USA and EU

USA

Home related accidents Nowadays, there is a big factor that influences the lives of children all around the globe which is represented by the dangers in their own environment, in their own homes. According to RoSPA article, more than £275 million a year is spent for these types of accidents. Even if the word “home” should mean a high level of safety, relaxation and good mood, there are cases where it might endanger the lives of people you love. According to another article, most of the accidents take place at home. Children below nine are more exposed than the older kids, mostly because of unconscious acts that they do not percept.

As presented in the diagram above, children below one year have the highest chance to be implied in an accident, mostly because of suffocation and choking caused by their curiosity to examine things around them by putting the objects in their mouths. The most severe injuries are associated with heat-related accidents and fall from high places, so even if the most accidents were encountered in the living/dining room, the most serious ones happen in the kitchen and on the stairs. According to the World Health Organization, most of the heat-related accidents happened because of hot liquids(scalds), hot solids(contact burns), or flames(Flame burns). These accidents regularly lead ask for hospitalization and longtime recovery. Often it leads to a lack of self-esteem and public rejection, which for a kid could affect the entire life. So, a good way to stop the curiosity of children to play with matches or taste hot liquids is more than necessary. Regarding the falls, around 10 children die each year by this accident. But, mostly, children that fall from stairs or high places encounter a trauma and possible some visible post-accident problems.

Other home-related accidents are poisoning and drowning.

Another study states that more than two million calls per year are about exposure to the poison, from which almost all of them occur at home and 80% are related to children between 1 and 4 years. As stated in the same article, the first tip to prevent poisoning is to install locks/childproof latches on all cabinets to restrict access to children, but in most cases, to keep a physical key is not really easy and it costs you a lot of time to lock/unlock it. Also, you might forget to lock it back, in case which just one mistake can cost the life of your beloved child. This tip is strong enough because it includes most of the others inside it(“store … out of reach and out of sight of children”, “make sure medications are in child-resistant containers”).

Related to drowning it is known that infants do not know how to swim, float or avoid dangerous situations, so just a few cm height of water can provoke drowning. According to CDC article, children aged between 1 and 4 have the highest drowning rate. From all the possible accidents, almost one-third are related to drowning which often occurs in the home swimming pools. In this case, the parent shall be almost in permanent presence of the child, but in any special circumstances, a system that will announce you in time, or prevent the accident can be handy.

Unintentional home injury deaths

From 1992 to 1999, there was an average of 146.970 injury-related deaths annually in the United States, with an average annual injury death rate of 54.90 per 100.000 persons. This is a total of all age groups and all possible injuries, in and outside the house. In Table 1, the location of the fatal unintentional injuries is listed.

Category	n	%
Transportation-related injuries	44.830	49
All other injuries
Home	18.018	20
Other	11.762	13
Unknown	14.596	16
Blank	1.622	2

Of the injuries with a known location, an average of 18.048 unintentional injury deaths occurred annually in the home environment. This represents an annual rate of 6.83 deaths per 100.000 persons. Although the location was not recorded for the 44.830 transportation-related injury deaths, some proportion of those deaths may also have taken place in the home environment such as yards and driveways. These are all the fatal injuries with known locations for all age groups, for us only the age group of 1 to 9 is important. In Table 2 is listed what the average annual unintentional home injury death rate is per age group. This table also shows how many accidents occurred by males and females. This is not interesting for us, only the last group, the total, is relevant.

In this table, it can be clearly seen that 10.1 % of all the fatal home injuries which have occurred in the home annual, were in the age group 0 to 9. This is a significant number and shows that fatal child injuries inside a home are a real problem. Key for us is now to determine what the cause is of this big number so the system can prevent fatal injuries on this.

In figure one, there is a graph which clearly shows the major causes of injury fatalities by a range of age groups.

Apparently, fires and burns, inhalation and suffocation and drowning were the leading causes of unintentional home injury deaths among children aged from 0 to 15 years old. Fire/burn deaths were the leading cause for children from 1 to 9 years old and drowning the second leading cause. For children below the age of 1 inhalation and suffocation was the leading cause and fire/burns the second, this is not visible in the graph. Nearly all fire/burn injury deaths among children aged below 15 were the result of residential fires. The majority of drowning deaths among infants occurred in bathtubs.

Unintentional home injury death rates among children varied by age, with infants having the highest death rate. An average of 469 children aged below 1 year died each year in the United States as a result of a home injury, in which the majority were due to choking and suffocation incidents (62,8%). Children aged between 1 and 4 years had the second highest rate of home injury death per year, in which the majority of 75% were the result of residential fires and drownings (43.7% respectively 29.3%). These numbers show that the system really can make a difference with injuries due to choking, drowning and fire/burns. But there is an objection. These results are originating from an average death rate from 1992 to 1999. One can say that the safety then was worse than it is now and that therefore these numbers are not significant anymore. But this is not exactly the case.

From 2000 to 2008, there was an annual average of 30.569 unintentional injury deaths occurring in the home environment in the U.S.. This number is almost twice as high as in 1999 where the annual unintentional home injury deaths were just more than 18.000. In figure 2 it becomes clear that the most unintentional injury deaths are caused by poisoning, fall, fire/burn and choking/suffocation. This does show that these causes are also the biggest issues from the year 2000 to 2008

In figure 3 the age-adjusted rate of unintentional home injury death’s is shown.

One can clearly see that the 3 major causes of unintentional home injury death of the age group 0 to 9 are suffocation, drowning and fire/burn. Comparing this with the other numbers of the research from 1992 to 1999 is this the same result. It is clear that the fatalities inside a house for children stay about the same looking at the results from 1992 to 2008. Therefore we assume that these causes are nowadays still present and the system can make a difference when looking at Suffocation, Drowning and fire/burn.

Unintentional non-fatal home injuries

The non-fatal injury rate for children younger than 9 years old In the USA was 28054 per 100000 in 2000-2006. For this age group falls accounted for the largest amount of injuries. Getting struck by or against an object was the second largest cause of injuries. For children younger than 1-year-old fires/burns accounted for about 5% of the total amount of injuries(compared to 52% for falls). For children aged 1-4 cuts/pierce account for 4% of the total amount of injuries(compared to 43% for falls) and for children aged 5-9 cuts/pierce account for 7% of the total amount(compared to 37% for falls). When children grow older outside related accidents(cycling and car related accidents) become more important.

Table 1: Top Five Leading Causes of Unintentional Injury Deaths and Nonfatal Injuries among Children 0 to 19 Years, by Age Group, United States, 2000–2006

Falls from furniture and child care products are the most predominant ones for children younger than 1-year-old. For the older age groups injury by falls still predominantly are indoors(falling of stairs, the bed and tripping over objects like toys). For children younger than 5 years old falling out of the window is significant compared to the other age groups. Burns are most often happen in the kitchen or in the vicinity of hot water(bathtub), but hot beverages and food can also cause burn injuries. Especially children younger than 2 years old are at risk to be burned.

A study conducted in the late 1990’s also showed an alarming number of accidents that happen in the home environment. This study, however, included the yard, porch etc. into their definition of the home environment making the data not as solid, but it will still give a good insight for our purpose of the SMART home. The NHAMCS data indicate that nearly 9.8 million emergency department and 1.4 million outpatient hospital visits were made in 1999 for nonfatal, unintentional injuries that took place in a home environment as shown in Table 2. Likewise, data obtained in the NHIS include 12922220 nonfatal unintentional home injuries, excluding poisonings, requiring some form of medical advice. NHIS data also show that ≥750000 persons aged ≥5 years were reported as missing at least 1 day of school, as a result of an unintentional home injury.

Table 2: National estimates of number of nonfatal, unintentional injuries, by location, United States, 1998–1999

Each data set identified falls as the most common mechanism of injury by far, accounting for 36.2% to 45.7% of the injuries or visits to healthcare providers for nonfatal unintentional home injury. The national estimates of the numbers and rate of having lost at least 1 day from work or school due to falls were 2145044 and 757044. Almost 4 million emergency department visits and 4.2 million office-based physician visits were made because of a fall in 1999. The second most common mechanism of injury varied according to the data source. For visits recorded in the NAMCS, NHAMCS-OPD, and NHAMCS-ED data sets, being struck by or against an object was the second most common mechanism indicated, with visit rates per 100000 at 439, 63, and 591, respectively. In contrast, the NHIS dataset identified cuts and piercing injuries as the second most common mechanism; the visit rate was 649 per 100000.

According to the data set people older than 65 are at the highest risk of getting injured followed by children younger than 14 years old as shown in figure 1. This shows that young children are at risk of unintentionally injuring themselves via an accident at home. Among these children falls, cut/pierce and struck by/against are the main causes for an injury which is consistent with the data from early 2000.

Figure 1: National estimates of the rate of non-fatal unintentional home injuries, or injury visits, by age group, United States, 1998–1999

EU

Injuries are a leading public health threat to children in the WHO European Region. Many children die or experience pain and disability from injury throughout the Region. Children are especially vulnerable to injuries. They need special consideration to safeguard their right to health and to a safe environment, free from injury and violence, as emphasized by the United Nations Convention on the Rights of the Child. Every society is responsible for ensuring that this fundamental right is fulfilled. [1]

Unintentional injuries are the leading cause of death among children aged 5-19 years. In 2004, 42 000 children and adolescents aged 0-19 years died from unintentional injuries in the WHO European Region. But the impact of injuries is much greater, with millions of hospitalizations and emergency care visits. [1]

Although injuries are a leading cause of the burden of disease and seriously drain health and societal resources, they have not been a high-priority area for action in most countries until recently. The leading mechanisms of death from unintentional injury in children are road traffic crashes, drowning, poisoning, thermal injuries and falls. [1]

The home is of particular importance when analyzing child injuries as it is the environment in which young children grow up in and achieve developmental milestones by interacting with their physical surroundings. In just the United Kingdom alone, 75 children under 15 years of age died due to home injuries in 1 year, ∼25% of all child injury deaths. A child’s injury risk within the home is a joint interaction between the caregiver, the child, and the home environment. Both unintentional and intentional injuries are of importance as the majority of infant/child homicides occur in the home and so do the majority of adolescent suicides in a teenager. [2]

In different countries from the East and West of Europe with variations in income levels. 60% of injuries to children under 1 year of age occurred in the home environment, compared to 11% in transport. In contrast to fatal transport injuries, which increased as age increased, Table 1 shows the fatal home injuries as highest in children under 5 years of age both in numbers and proportions of the total and then sharply decreasing. For children between 0-9 years the fatal injuries at home account for 38% of the total fatal injuries. [2]

Location of fatal injuries by age, average annual number and percent, 16 European countries, 2002-2004

The top four causes of unintentional fatal home injuries in children 0–14 years in all countries aggregated were drowning/submersion, fire/flames, poisoning and falls(Table 3). These causes accounted for almost 75% of all home injury deaths. [2]

Home injury deaths in 16 European countries, annual number, percentage, age 0-14, all causes, 2002-2004

In comparison to fatal injuries, non-fatal injuries at home account for about 45% of the non-fatal injuries. For children under 5 years, 59% of these injuries are caused by falls from heights or other falls. As age increases, the home injuries decreases. For children from 5 to 9, 38% of the non-fatal injuries happen at home. [3]

a) Main places of occurrence of non-fatal child injuries by age group. b) Mechanisms of home injuries in children under 5 years of age.

So as can be seen in this data, fatal and non-fatal injuries under children happen more than often. Accidents and injuries at home account for a majority of the total injuries. Since these injuries are a big public health threat to children and have a big impact on the society, preventing these risks and accidents have to become more of a priority to satisfy the right to health and a safe environment as emphasized by the United Nations Convention. Since a big part of these injuries happen at home, this can be a good start to implement risk prevention and enhance the safety and decrease the injuries of children.

Sources: [1] http://www.euro.who.int/__data/assets/pdf_file/0003/83757/E92049.pdf [2] https://academic.oup.com/eurpub/article-lookup/doi/10.1093/eurpub/ckq047 [3] http://www.eurosafe.eu.com/uploads/inline-files/IDB_Report_2014_final%202010-2012.pdf

State of the Art Childproof Equipment

Unreliability of Childproof equipment

Nowadays, childproofing a house is using simple measures like locks and blockers to increase the safety of a house for a child. A child is not able to open these locks and dangerous situations are in this way avoided. For example, plug covers or plastic locks for a cabinet or bottles are used to childproof a house, in short, it’s denying physical access to a potential danger. Most of this child proof equipment is designed in such a way that when it is installed, grown-ups can still access these dangers but children do not. This means that childproofing is giving up some comfort in favor of child safety. For example, a magnetic lock for a cabinet can’t be opened without the use of the magnet key which can be inconvenient if a grown-up doesn’t have that key at a specific moment and needs to go get it from a different room.

Giving up comfort is not the only problem with these simple measures, these safety measures do not always guarantee safety for the child. This is because a child becomes stronger and more clever when they become older and because these safety measures are designed so that adults and seniors can still open them. Take for example safety caps that are used on medication and cleaning products. A 2-year-old has a 2% of opening such a safety cap and if the child has observed an adult opening such a cap, then this chance rises to 8%. So for very young children these measures work properly. For a 7-year-old the chance to open it is already 60% and rises to 74% if it has observed an adult. The chances of opening such a cap increase with age and it shows that they aren’t reliable. Especially children who get the chance to watch their (grand)parents opening such a safety cap are able to open it later. A child only needs a couple of seconds to a minute to open a cap which means that parents have to keep an eye out constantly.

One of the major reasons that children are able to open these caps is because seniors need to be able to open them as well. Seniors often need medication and if the safety cap is too difficult to open, this can cause problems for the seniors' health. A 60+ year-old can generate about twice the torque than a 3-5-year-old. However, 8-12-year-olds can already generate about 80% of the torque that a 60+ year can generate. This means that caps that can be opened by seniors, which are most of them, can also be opened by older children but also by above average younger children when it comes to strength or intelligence. Another reason why these caps can be opened is that of comfort. Adults who open such a cap will put stress on their hand's joints which cause discomfort. If the caps are too hard to open then people will not buy them because of this discomfort. Also notable is that a 3-5-year-old is able to generate more torque using a 3-fingered grip than any adult using a 2-fingered grip. The 3-fingered grip is the most common and the more natural grip to use to open such a cap which shows that a young child isn’t weak by any means.

These examples show that children learn from their parents to open childproof safety measures which make these safety measures less reliable. Also, these safety measures aren’t made to be extremely difficult to open because adults need to be able to do that. The cleverness and persistence of children also shouldn’t be underestimated. For example 1 in 4 children in Ireland successfully opened the door of a moving car and about 76% was able to free themselves from their straps. The only solutions to combat such problems is for the parent to be very observed of their children, but of course, this isn’t always reasonable. Parent are humans and therefore will make mistakes or forget and that almost always results in problems with their child.

Simple gate

Types

There are three basic types of Baby Gates: Pressure Fit Baby Gates, Hardware Mounted Baby Gates and Child Safety Gates for Wide or Irregular Areas:

Pressure Fit Baby Gates - In the past they were simply barriers than were wedged between two walls or in a doorway and you had to step over them in order to go through or remove them completely. Much has changed. Nowadays the gate itself stays across the opening and is held in place by the pressure that is usually created by extending threaded pressure pads to the wall or door jam, these gates have a door that can be opened and closed for convenience. Because this type has a gate within a gate it also has a threshold across the bottom when the gate is opened. Two things all pressure gates have in common is that they require two flat surfaces across from each other to be mounted against and they can't be mounted on an angle. These gates generally are not designed to be mounted on staircases.

Hardware Mounted Baby Gates - These gates are sometimes also called stairway gates because they are the most appropriate type of child safety gate for a staircase. They are versatile and when mounted properly they are easy to open. Most can be removed easily from the mounting hardware if there are occasions when having a baby gate installed is not appropriate. These gates also come in different shapes, sizes, and colors. Some have the added ability to be able to be mounted on an angle if necessary. The ability of these gates to mount at different angles vary, the gate that can be mounted at the steepest angle is the angle mount safe way.

Child Safety Gates For Wide Or Irregular Openings - Wide or irregular openings usually take a little more time to plan but may actually end up being very simple to install. These situations require you to do a little creative thinking.

Accidents

Baby gates are one of the most widely used home safety products to protect children from home hazards. The objective was to describe the epidemiology of baby gate and barrier-associated injuries among children. It was hypothesized that injuries experienced by children ages ≤2 years and those >2 years were significantly different as a result of differences in gate interactions. An estimated 37,673 children were treated in emergency departments for injuries associated with gates, yielding an average of 1794 cases annually. The incidence of gate-related injuries increased significantly from 3.9 per 100,000 children in 1990 to 12.5 per 100,000 children in 2010 (P < .001). Patients were primarily boys (61.0%) and were <2 years of age (60.4%). Patients <2 years of age were most often injured by falls down stairs (odds ratio 6.72; 95% confidence interval 6.32–7.16) after the collapse of the gate. Patients aged 2 to 6 were most often injured by contact with the gate (odds ratio 2.03; 95% confidence interval 1.95–2.12), resulting in open wounds (55.4%) and soft-tissue injuries (24.2%). Given the clear dichotomy between injury characteristics of patients aged <2 years and patients aged 2 to 6 years of age, as well as the prevalence of preventable injuries, greater efforts are needed to promote proper usage, ensure safety in product design, and increase awareness of age-related recommendations for use of gates.

Design Requirements

For the design of this part of the system, first, the design requirements are set. These elaborate on what conditions the system should satisfy and which specifications should be met.

Stairs

To target the largest group of potential customers, the system should be able to operate at as much different house settings as possible. The staircase itself can deffer per house and the system should be able to be implemented in every house. The design should be applicable for every type of stairs. For example U-shaped stairs, normal straight stairs or curved stairs.

Hallways

The hallways can also differ per house. To make this design albe to be used for most houses, the most common hallways settings need to be determined. The way the stairs are connected to the hallways determine important parameters for the safety. Some situations contain a higher risk than others due to the distance between the stairs and the closest room, or due to limited visibility. This design then should be applicable to hallways and stairs combinations that on the top side are shaped as L or U, or stairs that end in a cross- or T-intersection with the hallway. In figure x below the most common possibilities are showed.

Gate

The system will prevent children from falling down the stairs and will enhance the safety of the child around the staircase. While fulfilling this task, the system should also not be inconvenient for the parents or other people in the house. It should not be an obstacle of some sort and still function properly. In the design, there should then be a gate on the top and bottom of the stairs. For convenience, the gate should move only in a plane direction. If the stairs are designed in such a way that a gate will not cover the entry of the staircase, then this should be solved with an extension of the gate but separately installable. The material of the gate should be sturdy and strong, but also not at harm for children. The edge which closes the gate to the wall should not be too hard and child safe and sharp edges should be avoided. The height of the gate should be equal to the standard that is set for these safety gates, this is about 0.7 to 1 meter in height. Since these gates should open and close automatically, it should satisfy a “certain minimum and maximum speed’’. So that it is safe and realizable, but also quick enough to be closed in time while not becomming an extra danger for the child.

Danger Zone

The system should have an implemented danger zone or reaction zone in which the gate should open for the parent and close for the child. This zone has a safety margin so that the gate is always closed when the child is in this zone. To notify the parents when the child is in this zone, LEDs should make this visual from all directions. This notification part should be implemented in the gate so that it does not have to be installed separately. This way the system can guarantee safety and comunicate with the parents.

Recognition and detection

The system is there for the protection of the child(ren) in the house, but also to reduce the stress of the parents. Therefore the system should be able to accurately distinguish between adults and children. Besides recognizing the people in the house, it should also be able to detect where they are. It is of importance that the system is able to track the distance between its goal, in this case, the stairs, and its object of interest, in this case, the person (either an adult or a child). This detection and recognition sub system is key for this system to work, since it will take care of the convienience. If it does not work properly, the system fails his goal where it is designed for; guarantee safety and bring more convienience for the parents.

Operating and working of the system

The system must be able to work with the information it gets from the detection and recognition software. The information that is acquired must be processed and converted into actions. This processing and converting must be done almost immediately. Therefore the system must be able to work together with multiple components at the same time.

Recognition and detection systems

For the system to work properly, a proper detection and localization system has to be chosen. The system has to know if there is a person in the defined space and to know its location to at when necessary. It is also necessary for the detection system to be able to differentiate between children and adults because the system has to act when a parent is near the gate. A few different detection systems have been investigated and compared to choose the best one. There is also looking to the set requirements to make sure the system satisfy these requirements.

Infrared Detection

One way to locate an object is by making use of infrared (IR) sensors. Simple IR sensors are widely used nowadays in robotics and automation, process control, remote sensing, and safety and security systems. More specifically, they have been used in object and proximity detection, counting, distance and depth monitoring, floor sensing, position measurement and control, obstacle/collision avoidance, and map building. Since the great variety of applications of IR, IR sounds promising for the detection of a person and the differentiating between adults and children.

IR is also commonly used for face recognition systems, most of the time for safety reasons. Thermal face recognition deals with the face recognition system that takes the thermal heat of the face as an input. Thermal human face images are generated due to the thermal human body heat. Such a face recognition system would be also applicable for the differentiating a child from an adult. The generated thermal human face image of the observed person could be compared with an image of the child out of a database and in this way the system is able to differentiate the two. A downside of such a system is that the resolution of the thermal images is not very high. Also is it very plausible that the child will not always look straight into the camera, so different face position and also facial expressions should be covered by the system These downsides together with the high cost of such high-end IR cameras make this application of IR not interesting for this application.

Since the costs of such a system, to be able to cope with the state of the art, has to be as low as possible, the localization system should not be too expensive. Therefore the applications of low-cost IR sensors is investigated. To still be able to differentiate objects, the differentiating techniques employed should be different from such operations performed on conventional images. The targets which have to be differentiated are not patterns in a 2D imaged, but rather objects in space, exhibiting depth and at different positions with respect to the sensing system. This would be a common situation which often will occur when the system is in use for our specific scenario.

There are different techniques one can use to differentiate the geometry of an object with such low-cost IR systems. Here we only discuss the template based approach to differentiate only the geometry of the target object, since only the geometry is important for this application. he template-based approach is based on comparing the acquired IR intensity scans with previously stored templates acquired from targets with different properties. Hence, this approach relies on the distinctive natures of the IR intensity scans and requires the storage of a complete set of reference scans of interest. For targets made of the same material, but with different geometrical properties, the correct differentiation rate is 97 percent.

The geometry of children and adults is a major difference since a child is much smaller than an average adult. Therefore only a rough estimation of the size of the object is enough to differentiate a child from an adult. The geometry itself is therefore not important, one could approximate the person as a solid block or cylinder with specific dimensions of the length, width, and depth. To determine the full geometry of a person is also way too complex for such a low-cost sensor. Since it is possible to determine the size of an object, this technique would be suitable for this application.

So far this system sounds very promising. The sensors used are of low cost, it is able to detect whether there is a person in the room and the differentiation of the geometry is of great accuracy. There are only a couple remarks to make.

The system determines the geometry by sensing the object, therefore the sensor should be mounted on a gimbal which can rotate the sensor in all directions. IF the sensor is not able to rotate, it will not be able to fully sense the target and detection and differentiation becomes impossible. Since the system can only determine simple geometries, objects as for example furniture can cause false positives and negative for this system. The system can track these objects and because the geometry of a cabinet can be the same as the modeled geometry of a child, the simplicity of this system can become a problem. The last problem is that it cost time for the system to fully observe the target since the full geometry has to be sensed. Moving targets, therefore, become a problem, because a child that moves will not be fully scanned by the system and therefore detection and differentiation become impossible. The simplicity of such low-cost IR sensing systems is preferable and promising, but due to the downsides of it as listed above, this way of using IR will not be suitable for this application.

WPIR

Infrared can also be used in a different way. In the section above is discussed how IR sensors can be used to locate objects in an environment using the intensity of the reflected light. However, IR can also be used to locate objects by thermal mapping. There exist an indoor localization and monitoring system, which is based on a wireless and PIR (WPIR) sensor fusion system. The PIR sensor transforms incident IR radiation into an electrical signal. PIR detects changes in temperature coinciding with movement of a person or object in the environment. The output of the PIR sensor is in disorder for human movement detection. A human walking through a PIR sensor detecting region and the corresponding output signal is shown in figure L.1.

Figure L.1: The functionality of a PIR sensor

WPIR has proven it can monitor multiple targets with relative good resolution. This is promising for the SMART house application, but it needs to be able to differentiate between adults and children. It is possible for WPIR to differentiate humans and robots. This because the signals the sensor receives are different when a robot passes the sensor and when a human does. Based on this, WPIR is able to differentiate. But since the signal of adults and parents probably will not differ much because the thermal properties are the same, WPIR needs some adjustments to be able to differentiate children from parents.

What is very promising of WPIR is that the implementation is very easy and the costs are also low. The only hardware needed is a ceiling camera which can observe the environment. Since it is also possible to monitor multiple targets WPIR can still be suitable for this application, but then the problem of differentiation should be solved.

Ultrasound Localization

The ultrasound system is not always on the point of view of the today technologies, but there is no reason for this. Even nature shows us that the ultrasound detection system works fine in any types of conditions. How exactly does it work? Bats have this power to orientate themselves only by using ultrasound waves that at the contact with objects return to the source. Based on the time of such a routine, the bat can detect exactly how far the target is.

This feature sounds good and it seems to work, but there is a big counter argument for using it. Especially in our case, where the subjects are young children. This method is an invasive one, which in the long run can cause a lot of problems, especially because of its chemical effects. As stated in “The chemical effects of ultrasound” , it can drive metal particles together at such high speeds that they melt at the point of collision, and ultrasound can generate microscopic flames in cold liquids. As it is already known, in blood there are different metals like Potassium, Iron, Calcium, Mercury, Sodium and many others which can react to ultrasound waves. Effects that can occur are related to headache, dizziness, and nausea, but most important one is the hearing damage. So far, the most difficult part of using such a technology is the long time exposure of subjects to it and the age range of our subject is below 9 years. Young people are more sensitive to any types of factors compared to adults, hence it is difficult to integrate this technology into the current project analysis. The same document stated that the technology is useful for industrial applications because it can radiate through large volumes of liquid, but for our purpose, it will represent a barrier instead of a helping tool. Since due to this downside ultrasound is not an option, this detection method is not further analyzed.

Pressure Sensor

A pressure sensor is a device that can notice when there is put pressure on it. It can be used for this application when the sensor is placed before the staircase. The sensor can be set so, that it only sends a signal when a minimum force is put on the sensor. This way, the sensor is still able to differentiate between children and adults.

The downside of this type of detection is that a sensor cannot sense multiple people, it only senses when there is put pressure on. This way dangerous situations can occur, when for example a child walks after it parent which is going downstairs, a dangerous situation takes place. The system does not oversee the whole environment and this can cause problems. Also, the measurements can be easily tricked since the sensor only measures weight, a child can easily trick this by for example hold something heavy. These downsides lower the accuracy of the detection method and this does not have a good contribution to the system when maintaining safety is our main goal.

Active Badge

The active badge is a badge that a human wears so that he/she can be tracked by a sensing system. The Active Badge operates as a beacon, regularly signaling a unique code to a network of sensors distributed around the area to be monitored. Sightings are gathered by using a master processor which polls the sensors through a network provided for the purpose. The name and location of a badge wearer can be ascertained by looking up the badge ID in a table and looking up the location where the sighting was made. It has been continually improved on to make it more accurate. Because of these improvements, this technology is applicable for the SMART home, because it is able to track multiple people, even through walls and it isn’t expensive to implement. Since every user has its own ID, differentiating between adults and children should not be a problem. A disadvantage is that the users will have to wear these badges which might be considered inconvenient by adults. On the other hand, a child might not wear it, for example when the parent forgets to put it on, or even destroy it while wearing it. Also if the badge is attached to a piece of clothing is the child able to remove that clothing. If a child is not wearing the badge, the system won’t be able to track the child and the same as with the pressure sensor, the system does not oversee the full environment. These downsides bring the accuracy down to this detection system since there are a lot of bugs which can let the detection fail.

Camera Detection

Another detecting system is camera vision. This alternative represents the best one for indoor use for detecting people. It is not invasive, which means it can also be used to detect children, it is rather cheap and efficient. But what is the state of art of such a technology? The latest cameras are connected to the internet of things which makes them SMART. They are able to process via an Ai all the given images and provide helpful data. The bad side of it is represented by the privacy issues, but looking at the SMART house application which is the underlying thought of this project, this would not be a problem since such a house consists of multiple sensors.

Camera systems like ‘Kinect’ are able to track and observe people. This is done by software which analyzes the camera image of the Kinect camera system. This is done as showed in figure L.2.

Figure L.2: Detection and tracking with camera vision

A person detector which makes use of such Kinect camera data or RGB-D is HOG (Histograms of oriented gradients). HOG is nowadays one of the most performant and widely used methods for visual people detection. The method considers a fixed-size detection window which is densely subdivided into a uniform grid of cells. For each cell, the gradient orientations over the pixels are computed and collected in a 1D histogram. The intuition is that local appearance and shape can be characterized by a distribution of local gradients without the precise knowledge of their position in the cell.

With the HOG and the RGB-D, an image can be created where a person is detected and marked with a colored box. The height of this box can be determined and in this way, adults and children can be differentiated from each other. Because the height difference between an adult and a child is big enough, the accuracy of the height of the box is not that important since the box of the adult will be way bigger than the one of the child. Therefore, the accuracy whether a person is detected or not is more important than the accuracy of the box itself. The performance of the people detection system is evaluated in terms of detection rates (accuracy) and false positives/negatives. True positives are the people images detected from the ground truth. False negatives are the people images not detected from the ground truth and false positives are images detected as people that do not appear in the ground truth. It is logical that the system will fail when the adult is not detected by the system but wants to go down the stairs, a false negative. Also, dangerous situations can appear when a false positive is detected and the child has a free entrance to the stairs. The accuracy of the detection system is then defined as follows:

[math]\displaystyle{ Accuracy=\frac{TP+TN}{TP+FP+TN+FN} }[/math]

With TP, TN, FP, and FN are respectively True Positive, True Negative, False Positive and False Negative.

It turned out that these typical camera systems have an accuracy of about 85 to 90 percent. For our system, this means that on average one in ten times the system fails and the parent has to wait or open the gate by hand. According to an article, the accuracy of this system rises if the camera uses thermal images. False positives are most commonly generated by obstacles and other objects which are placed in the room. When thermal images are used, these objects are not observed anymore since they do not generate any heat. The accuracy can rise to 92 percent or higher, depending on the resolution of the camera. This method will be elaborated later.

Another advantage of using thermal images instead of normal camera view is that a normal camera fails when operating in the dark. Persons cannot be detected when the camera has lost all his vision. To cope with this problem again thermal images comes in handy, a thermal camera will not loose its functions when the environment is dark since heat is always generated by the targets.

The second problem of normal cameras is that the precise location of the target is not known. The detection system uses the 2D image to detect the targets, this can cause some problems. For example, imagine a child in front of the image and an adult in the back. When the detection system does his work, the two boxes may be of the same height because the parent is much smaller in a 2D image when it is positioned further back. The system, therefore, lost its property to differentiate properly. To still know the exact location and height of a target and prevent false positives from happening, a device which measures distances is necessary for this system. This makes the system more expensive, but the accuracy will go up together with the reliability. When the distance is known and the height of the box, the software of the system can do the rest by calculating the exact height and is able to differentiate. Also, the system can keep track of the target and see when it is near the stairs so it can act when necessary. Later more will be elaborated on this distance sensor.

Thermal Imaging

Thermal cameras are a really good way to detect people. They are often used by firefighters to detect the source of the fire or see the heat signatures of the casualties. This detection system is already in use and it was proved to be efficient, which may make it worth implementing in a SMART house. The main disadvantage is constituted by the fact that the images appear like 2d plane pictures, where the actual distances to objects are not known. For a real case situation where people can use these images to spot other persons thermal cameras perform well, but how do they cope with human detection when heat objects are around? Taken our study case, there might occur several problems with shape detection. The thermal imaging shows the details of a person usually in colors of red, yellow and orange. These colors are also shown for hot objects, for example, a cup of coffee.

Thus, the main problem for the Ai which shall detect persons for our project is how exactly to distinguish between a cup of hot liquid which is close to the camera and a person which is far behind? Since the shapes are not perfectly sharp, there might be used a human body template to look for persons in such images, but another question arises: how do you identify between two persons that are on the same line facing the camera? The image will show a bunch of heat and the Ai may identify one person, but it is impossible to find the second person just by using that camera. So, blind spots represent a problem for a system with only one such camera. Besides that, advantages of this detecting technology overcome most of the other ones. It is capable of detecting people with high accuracy(up to 100% if the environment details are loaded into the system and a good detection algorithm is implemented) and can help to detect them through smoke and darkness. The capability of detecting through smoke might not be needed for the purpose of the project, but the second attribute is really powerful since it can help during nights. The thermal images are also easier to process compared with regular images because they contain contrast between the heat source and regular space(usually yellow-red to green-blue). Thus, the differentiation between people and other regular objects is quite easy and efficient.

Comparing the systems

Of all the localization systems discussed above, one should be chosen to implement the system. The systems have all their pros and cons, the best system should be chosen. To choose the best system, the requirements should be addressed to make sure the system which can fulfill the most requirements is chosen. Below is a table with all the systems discussed, their downsides and advantages.

System	Multiple targets	Able to Differentiate	Easy to implement	Accuracy	Costs	Downsides	Advantages
Infrared sensor	Good	Yes	Yes	Good around 97%	Low	The target have to be stationary and it is necessary for the sensor to be able to rotate.	Very cheap with good accuracy, multiple targets is not an issue.
WPIR	Good	Not yet	Yes	Good around 95%	Low	Not able to differentiate yet.	Low in cost, high accuracy and easy to implement.
Ultrasound	-	-	-	-	-	It is an intrusive method and can cause harm in long-term use, so it is not further investigated.	-
Bracelets	Good	Yes	Yes	Good	Medium	Need to wear a bracelet all the time, hard to implement for guests.	Exact location detection, the best solution to detect every person.
Pressure plate	Poor	Yes	Yes	Low	Low	Might be easily tricked and does not oversee the environment.	Cheap alternative and easy to use.
Cameras	Good	Yes	Yes	80 - 90%	medium-high	Might have dead angles, not able to work when it is dark and distance is necessary.	Good vision range, easy to recognize people by using Ai and easy to implement.
Thermal Imaging	Good	Yes	Yes	good around 95%	medium-high	Might have dead angles and it needs a second distance measurement device.	Good vision range, able to function in the dark, easy to implement.

Conclusion

When all the above detection methods are considered, the best one can be chosen. The goal of the system is to maintain and guarantee safety for the child. Also, should the system hold all the requirements as good as possible which are set before? One requirement is that the system should be able to track multiple people and is able to differentiate between children and adults. The best two options then are thermal imaging and IR sensors. The downsides of IR makes it for some situation impossible to differentiate or even to detect the target. The best option for our SMART house application will, therefore, be the thermal imaging. Further in this report, at the design section, the thermal imaging will be further elaborated and a way to differentiate with this type of detection is investigated.

Design

Open/Closed System

There are two types of systems that can be used to solve the problem.

• The first one is that the gate closes after the system detects that the child is close to the stairs. With “close” it’s meant that the child doesn’t have enough time to reach the gate before it already has opened. This time would be determined by taking into account the closing speed of the gate and the average speed of a running child. After this is determined a distance can be taken that would give the system enough time which would create a danger-zone. When the child enters this zone the gate closes. However, this type of system has many issues. First of all children of different ages have different average speeds which mean that the size of the danger-zone would have to be changed constantly. The danger-zone could become so large that the system no longer is able to do its job properly. If for example the whole hallway is considered dangerous the system can no longer work properly. Secondly, the child might enter the danger zone but that doesn’t mean it wants to go to the stairs. The child simply might walk past the stair so that it can go to a different room or the child might turn around halfway through. This means the system would constantly be closing the gate for no good reason and that should be avoided.

• The second type is that the gate only opens after the system detects an adult. This type of system is more advantageous than the former one because it deals with most of the presented issues. The average speed of the child is no longer important and the size of the danger zone can be reduced significantly because the urgency factor is taken away. The system will also be nervous because the systems danger-zone is much smaller and it no longer has to take the erratic behavior of the child itself.

Because the second system is more advantageous than the first one we have decided to use such a system instead.

Walking speed

The average walking speed of humans is 1.4 m/s but can go up to 2.5 m/s. The average running speed of normal humans differs from 4.4 m/s to 6.7 m/s. Since the subject in this project is a child, these numbers are way too high. For the children group from 1 to 4 years, the approximated average maximum speed is about similar to the normal walking speed of a human, so about 1.5 m/s (which in most cases will not be reached). For the age group 5 to 9 years this speed gradually increases the older they get, but will not rise above the average running speed of normal human. So this maximum value can be approximated at 2.5 m/s at the age of 9. Due to certain factors such as education during the early years and the small distances the hallways provide, these speeds are most of the time not reached around the staircase. Especially considering the time for accelerating and decelerating the maximum distance they can travel in a time window is a lot lower than their actual maximum. An estimation can be done, which has a safety margin, at 2 m/s for the older children. The gate should be quick enough to fully close in time when the child enters the ‘danger zone’, and the time the gate takes for closing should be less than the time it takes for the child to cross the danger zone.

Speed of gate

The speed of the gate is dependent on the motor that is going to be used and the amount of RPM (Rotations per minute) the motor can reproduce. With the use of a matlab script some calculations have been done. With some average motors that can rotate at an rpm of 150 to 200 the opening and closing speed of the gate can be approximated to be somewhere between 0.5 and 1.5 seconds. For this design, a motor will be chosen that has at least 180 rpm, so that the opening/closing time is a little bit more than 1 second. For the gate material something light weighted is prefered. For the calculations a rectangular tube profile is used for the beams of the gate, with the dimensions 25x25x750. In the Matlab script, the torque that is needed is approximated at 1 Nm. Thus the motor should have a torque of at least 1 Nm. This is a motor that would fit the bill.

Danger Zone

The maximum speed of a child can be approximated to be around the 2 m/s. But since the child will not be running on its maximum speed the whole time, the estimated average speed of the child is therefore set at 1.2 m/s. The dangerzone has to make sure that the child can never come between the gate and the opening, therefore also a safety margin has to be added. Together with the opening and closing speed of the gate, the dangerzone radius is chosen at 1.5 m. The LED lighting to make situations visible, warn the parents and get the attention of the parents will be placed in the top of the gate, pointing upwards. This means these lights are always visible, even when the parent is carrying something that blocks his/her view to the floor.

Recognition and detection

The detection and recognition software shall be able to process given thermal images. As a result of processing, the human bodies will be discovered from the given image and a possible differentiation between a child and an adult follows. The image is given in a RGB format, every pixel taking three value between 0(minimum) and 255(maximum) for the red, green and blue details of the pixel. These colors have the purpose to represent heat details of the image: from blue(cold heat signature) - green - yellow - orange - red(hot heat signature). The colors are correlated to the reality heat temperatures, so by using the contrast between colors it becomes easy to detect a person when no heat source is close. The processing is done for every pixel one by one where the color is detected and in case it is between the threshold values set by us, it will be converted to a white pixel in a new created image. Finally, the image created contain only white areas that represent the heat signatures from the given thermal image. Now, the detection part has to come in handy and be able to distinguish which part of the image belongs to which person. The detection is done by saving the maximum and minimum X and Y values of the shape. If the distance between the pixels is larger than a threshold given by us, the program shall consider a new person is present in the picture. Of course, it is consider as being a valid person if these values make sense and the height measurement > width measurement of the shape. In order to process images, OpenCv library is used for C/C++ code. Even if the image processing looks easy and fast, it takes a few seconds before the task completes because every pixel shall be analysed. For a full hd image it is needed to compute 1920x1080 pixels values.

Source code: File:Source.zip

The working of the system

The system will use a “gate closed” principle. Thus the gate will always be closed unless the parent is detected in the ‘danger zone’. The system is detecting the position of the subject in the hallway constantly (when movement is detected). So when the parent is moving towards the stairs it will already calculate time and its actions. When both a parent and the child are detected in the danger zone, the LEDs change to an alarming and to a striking preference color. This also means that the gate will not open when the child is in this zone, due to safety precautions. So when the parent is walking towards the gate and comes in a certain proximity of it, and there is no child in the danger zone radius, then the gate will open automatically and the parent can just walk through the gate and down the stairs without any inconvenience, and when the parent is on the stairs, the gate will close behind them.

Gate design

At the top of your stairs only use hardware-mounted gates. Pressure-mounted gates are ideal for between rooms or at the bottom of the stairs, but they are not strong or safe enough for the top of the stairs. If you choose an accordion-style gate, make sure it has a top filler bar. If it doesn’t, the child may get his fingers, hands or head caught in the spaces. The gate should only move in one plane and should be installable for every stair casing. The design of the gate then will be a casing with the height of the gate, that can be mounted on the wall or on the stairway railing itself. On the opposite site of the mounted casing, there will be a rail where the gate shall fit in, and this will make the construction stronger and so that it cannot be pushed out. This rail and the end of the gate are finished with a soft, child-friendly material for the safety of the child when being near the (moving) gate.

The gate design requirements are determined and a first design sketch was made. In this overview of the hallway and its setup the gate is described pretty concisely and is not yet specified. To show the way the gate is going to work, look and be placed in the setting, a CAD design of the gate is made. In this design, the materials are not specified and how it is going to look eventually can be different as well. The mechanism and the operating are visualized and the different parts are assembled. Below is the design and the mounting in a stairway visualized.

The front view (left) and the back view (right) of the gate.

The exploded view of the different components, these will get a further explanation in a components list in the future. On the right, you can see a frame view of the mechanism when it is folded in so that the gate is open. The plate on the front of the gate is representing a sheet of textile that is strong but soft to protect and prevent anyone from touching the mechanism from the hallway side.

For the setup of the gate when it is applied in a staircase it is shown mounted on a wall on an average staircase and hallway for example.

The gate closed in the example house.

The gate open in the example house.

Camera specifications

The camera needs to satisfy certain needs:

• has to be mountable on the ceiling (2.5 meters high)
• Needs to have a clear view of the entire hallway
• Needs an FOV of at least 90°
• Minimum range of 6 meters
• Quality of images needs to be good

If a camera satisfies these needs than this camera could be used for a SMART house. A couple camera’s that already exist and satisfy these needs are:

• Good 360 camera
• Good wide angle camera
• Good 90 IR camera

A 360 camera needs to be centred in both the hallway and the staircase. The hallway has a width of 0.95 meters so the 360 camera should be 0.45 meters away from both the walls. Because the width of the staircase is variable for different houses the centre would have to be measured by the user or the professional that installs the system. The 90 camera must be positioned so that the whole danger zone is viewable. The sketch shows the positions for each hallway where such a camera can be placed so that there are minimal dead angles. With a reach of 6 meters this camera is able to see most, if not all in some cases, of the hallway. By positioning this camera in a smart way no parts are needed that make the camera rotate.

Sensors

For an IR camera to be able to determine the difference between a child and an adult the system will need to know the distance of the person to the camera. An IR camera is unable to determine distances so additional sensors are needed. There are several sensors that are able to use IR light to determine the distance from that sensor to the object it is measuring. The first type of sensor uses a class 1 IR laser to measure distances. This laser can only be directed in one direction which means multiple would have to be used in order to be useful for our system. There is also the added problem with these kinds of sensors that they can’t be positioned easily in a hallway so that the measurement can be used by the system to eventually determine the height. Therefore this type of sensor wouldn’t work. The second type of sensor that could be used is very similar but it has a 360 degrees viewing angle which allows for flexibility in placement. These type of sensors can be used to measure the height of a person that is walking through them if you mount them on an angle a. When a person walks through this sensor it will start to measure the distance L, the distance from the sensor to the person. This distance L will decrease if the person walks deeper into the danger zone and it will decrease if the person walks out of the danger zone. When the person has fully entered the danger zone the last measurement data of the sensor can be used to determine the height of this person using the following equation:

[math]\displaystyle{ h = H-y = H-L\cos{\pi/2 - a} }[/math]

where H is the height of the hallway. Figure 1 shows a sketch of the situation. If this height h is too low that would mean a child is entering the danger zone and if this height is high enough it means an adult is entering the danger zone. The system is, therefore, able to determine the difference between child and adult. The system, however, does need to keep track of who’s inside the danger zone. This means that the system has to remember who entered it and who exited.

A sketch of the situation describe to measure the height using the second type of sensor

Both sensor type 1 and 2 use a laser of class 1 and although these lasers are considered eye safe it could be of a concern for certain people.

An alternative to these two types would be a sensor that uses LEDs instead of a laser, which would take away any viable concerns. These type of sensors are mounted on the ceiling and directed straight down and with a maximum measuring distance of 2 meters for black surfaces, they would still be sufficient for use in a hallway. It would have to be more accurately determined if this 2 meters still accurate if used on a black shirt or black hair to determine distances. For a white surface, the maximum distance is 8 meters. They have a measurement angle of 88 degrees which, for a hallway of 2.5 meters, would mean that you have a blind spot in the 2 upper corners of the hallway. This isn’t a problem however because these blind spots would have a height of about 1 meter which means that it can still measure if a person is shorter than 1.5 meters, even if this person skirts alongside the wall.

All 3 types of sensors use Pulse Ranging Technology to determine distances. With this measurement method, a powerful light source emits short, high-energy pulses, which are reflected by the target object and then recaptured by a light-sensitive receiver. During this process, the emission and reception times are detected with a high degree of precision. From the values determined, the distance to the target object is calculated using the runtime of the light pulses. If the target object is close, the light propagation time is short. If the object is further away, the light propagation time is longer. The main disadvantage these sensors suffer from is that they use height to determine the difference between a child and an adult. If a child raises himself such that could make the system believe it is taller than it actually is, he might lead to the opening of the stairgate.

Another way to determine the difference between a child and parent would be by using a thermal camera and PIR sensors. First, the size of the danger zone would be determined and that size can then no longer be changed. A PIR sensor is positioned on the ceiling on the every edge of the danger zone. This means you would need about 3-4 PIR sensors. The PIR sensors will tell the system when a person enters or leaves the danger zone. Because the distance between the thermal camera and the edges are set, using a height calibration, a person that walks through one of the edges can be measured. And if this person is tall enough the stairgate will open. An added benefit to this system is that the thermal camera can continue to track people inside (and outside) of the danger zone which makes it easier to keep an eye out on children. PIR sensors aren’t expensive which is also a benefit. PIR sensors also allow to divide the edge up in zones. This means that a person can be more accurately detected when they pass through the sensor. This can also help the camera, because the camera can only see in 2D. This can lead to problems if two people are in the hallway but one of them walks through the sensor while the order stands further in the background. The camera will think these 2 people are standing next to each other. But because the PIR sensor can determine which of these 2 people walked through a part of the sensor that information can be used by the camera to determine who walks into the danger zone and who isn't. In order for this to work, a thermal camera is needed and current technology already has 360 thermal cameras. A camera that is mounted on a rotating surface would work as well and there are plenty available.

In conclusion, the first type of sensor doesn’t work for our system. The second type could work if the system is able to remember who is inside the danger zone and if the class 1 laser that is used is eye safe, under any condition. The third type of sensor, using IR LED’s, has two disadvantages. Namely that children can pretend to be taller than they actually are and that it has only a maximum range of 2 meters for black surfaces. This means that a child could crawl under this sensor and not be noticed by the system. This could be solved by installing a PIR sensor in the danger zone. This sensor can then check if the danger zone is indeed empty. For this type of sensor, the system also needs to remember who enters the danger zone just like sensor type 2. The best detection type would be by using a thermal camera and multiple PIR sensors. The main disadvantage of this system is that it is more expensive than the others because thermal cameras are expensive. One issue that all these systems have is the situation of when somebody comes up the stairs and somebody is also in the danger zone. The system might make the mistake that the person that is coming upstairs is the person inside the danger zone and then would close the stairgate even though it should stay open. One way to solve this is by installing a PIR sensor onto the stairs because PIR sensors can detect the direction of motion of a person(See figure 2).

(a) A schematic presentation of a PIR sensor with dual sensing elements aligned in a motion plane. (b) It's output signal when walking.

Software

Code Details

The image processing starts from top left corner and the pixels are transformed to white pixels in a new image if they are within the boundaries. The new pixel image can be clear or noisy, so different adjustments like eroding/dilating pixels are needed. The minimum and maximum X, Y are saved as described above and their difference (Xmax - Xmin, Ymax - Ymin) is tested to be greater than a normal person dimensions such that no external heat can affect the detection. In the end, a rectangle is drawn by using these 4 coordinates. The combination of this camera and a distance measurement sensor it is possible to determine the position of the persons in the room and their size, such that the differentiation can be done between a child and an adult. In the end, the algorithm shows two images: the original image where a rectangle is used to surround each subject and a black-white image that shows the heat signatures that are considered in building the rectangles. If the temperatures decrease (like shown in the image), the algorithm cannot distinguish between the human and environment anymore, so only the heat parts are considered for detections.

L.5 Multiple persons detection

Further improvements

Design

Our proposed system has multiple shortcomings which need improvements:

• The first shortcoming is that the system can’t measure distances. It only knows the size of the danger zone itself and is then able to measure people on the borders of the zone but outside of the zone that isn’t possible. If distances can be accurately measured the system can detect people everywhere in the hallway which would make the system a lot more reliable. Our system could then also be more easily implemented in other parts of the house where it’s harder to use a fixed size for the danger zone. There are sensors that can measure distances in a human-friendly way but the range of these type of sensors is lacking. There is no real incentive yet to develop such sensors because most of these sensors are used in the industrial field so human-friendliness isn’t a big priority. It is advisable that more research in this field is done so that human-friendly sensors can be developed.
• Another problem is that the danger zone is some hallways is smaller than desired because of the hallway’s shape. For example a door could be inside of the danger zone which would mean that the distance between this door and the stairs is too short and that would put the child at risk. These rooms are essentially huge blind spots for our detection system. If the detection system is implemented in every room of a SMART house this problem would dealt with.
• Currently a casing of 20 cm is used to house the motor and the folded gate. If the size could be reduced more space would be left over for the users. This is desirable because hallways already are tight so every centimeter counts. The size of the casing could be reduced if the motor that is used would be smaller. It is expected that these type of motors will continue to shrink and still will be able to deliver the same amount of torque.
• High quality thermal cameras are also expensive which is a big disadvantage. However over the years thermal cameras have become more accurate and cheaper which bodes well for the future of thermal imaging. We therefore expect that these shortcomings will be dealt with in the near-future because all these shortcomings are technical related and history showed us that those type of shortcomings can be overcome.
• It is also needed that actual tests using this system are done to determine the effectiveness of this system. These tests could find more potential issues that would have to be dealt with.

Software

The localization is done as described above, but some downsides are present as it is expected for new technologies. If the subject stays close to another heat object, their shapes cannot be separated in code anymore since no clear way to distinguish which pixel each of them owns. This part of the algorithm shall be improved since the camera can detect you and your kid like one subject and behave abnormally without any reason. The solution to this problem can be solved with the distance sensor that can say which pixels are from which person and who is in front of whom.

A second improvement shall be developed in the person detection. In the example below, a cup of coffee is left on a table close to the thermal camera and the subject is far behind in the environment.

Since the current person detection is done by finding few black lines of vertical pixels between objects, any heat source that fits in the dimensions requirements can be misinterpreted as being a human. This ensures that the subject is connected with all his/her parts(even if they are few pixels apart from the main body, hands, legs and other small parts of the human body are considered as belonging to that person. The problem could be used by applying a modified BFS which shall test about 5 pixels in all directions, but it would be heavily inefficient since the complexity for a BFS with a huge number of possible neighbors increases exponentially.

Expansion towards other rooms

This system could be used for other dangerous area’s within a house as well. The kitchen could be secured in a similar way. The dangerous cabinets, the stove and the oven can all be locked and will only be unlocked when an adult is close. This way the child will be kept safe from the dangers of the kitchen. The system isn’t inhibiting on the adult when (s)he is using any of these dangerous things which are always more pleasant than a system that does get in the way. If a parent is cooking something on the stove the system is not allowed to cut off the gas/electricity if the parent walks away from the dangerous area. This means that the child could endanger itself. The system then should lock the doors that lead to the kitchen and these doors should only be unlocked when an adult approaches these doors. For the bathroom, the situation is similar, because the bathroom door should only unlock itself when an adult approaches this door.

There are two types of gates that are used to keep children away from the stairs: pressure-fit gates and hardware mounted gates. Pressure-fit gates aren’t suitable for up stair use because a child can push them causing the gate to no longer be stuck between the walls. A child could, therefore, push the gate and fall off the stairs. Besides this, the gate can either be opened by unlocking a lock and then swinging it open like you would do with a door. Or by unlocking a lock and then lifting the gate out of its position. The second type of gate is much more tedious but also cheaper, if all other conditions are the same. The swinging gates are both easier and faster to open than the lifting gates. This is mainly because the lifting gate has to be moved while the swinging gate only requires a light push. It takes about 2 seconds to open a swinging gate and the lifting gate takes about 6 seconds. This means that the new system has to be able to compete with these times and has to be easier/more comfortable to use.

USE-aspects staircase

The main problems that occurred in the USA and EU were related to falls, suffocation, burns, poisoning, and drowning. These problems can be solved in different ways, but no matter what, the impact and influence of them are going to be almost the same on the USE aspects. From a user point of view, a solution to all of the home-related accidents means less stress, more time for your activities and less money invested in medications and other treatment methods. The level of stress shall be considerably reduced since the house is self-aware and can handle bad situations for you. Also, the time needed for securing all the objects in the house and make sure that nobody gets hurt is cut off.

The system shall lock the objects where kids should have access. If there occurs a special situation that the system cannot handle, the notification system still gets you informed. Indeed the system will save a lot of time to regular users. Regarding costs, this one-time investment in a SMART house can get long term results for users that, by avoiding accidents do not pay for medical treatments and medicine, which nowadays represents a really big business.

For the social aspects, fewer accidents mean more happiness and reduce mental disorders. The happiness level would increase hence most of the people feel upset when an ambulance comes into the neighborhood and has to deal with one of their beloved neighbors. Besides that, deaths reduce significantly the happiness mood for everybody. On the other hand, accidents to children can negatively impact the mental health of their parents who can feel irresponsible or bad parenting. These problems in most cases affect people on long term and as said also reduce the level of comfort in their own houses.

By looking at this problem on the enterprise side, solving such problems is reduced in all the cases to fortune and income. The SMART houses are not widely popular because of skepticism of people about the efficiency of the products, but as like as SMART cars, they will get a good place in the population’s sight in the next years. Since it is almost a new area, there are plenty of ways to earn money by investing in such a concept, for example, SMART products, sensors, actuators, different types of safety subscriptions or any other type of feature that needs a small amount of money to be bought. And the most important step would be the integration of adds in houses, which as stated in the enterprise aspects above, will generate a huge amount of money.

As a short summary, the solution to the home-related accidents can influence in a positive way all the USE actors and their lives aspects.

Questionnaire

For this questionnaire to work, the person that will be questioned first has to be enlightened about our project. So tell them about the idea of a SMART Home, that our idea is to implement a part that helps parents with the safety of their children and that we first start with making the area where the most accidents happen (the staircase) is being looked at first.

After explaining the basics of our project, the interview can be started. At first, some basic questions should be asked:

• What’s a number of children and the ages of their children?
• Do/did you own a stair gate?

After these basic questions, questions can be asked about our main subject:

• How would you feel about a SMART Home that helps you with the protection of your child?
• What home-related accidents did happen the most to your children?
• Do you think that making the house safer, by using locks, stair gates and shutting off the hot water influences the child in a bad way? For example, the child would not learn danger from hurting itself because it was always protected from it.
• Where did most of the home-related accidents happen?
• What inconveniences in keeping your child safe should the system be able to solve or help with?

After that, some more in depth questions about the stairs itself can be asked:

• At what age were your children capable of getting up and down the stairs on their own without endangering themselves?
• Did you experience any inconvenience of the stair gate, like opening and closing it all the time?
• Do you consider a stair gate as a good safety option?
• Do you consider an automated stair gate as something you would buy? Even if it has a higher price than a normal stair gate?
• What would be the best operating mechanism of the gate for you? Always closed but opens when you are around it, or always open but closes when the child is around it?
• At what age do children really listen to and follow the “commands” you give them? For example, move away from the stairs.
• Should the gate take into account that both you and your child can be in the danger zone? So should it do something different from the situations in which only a parent or a child is in the danger zone?
• If it should, how could the gate take that into account?