USE principles

The main focus will be on User and Enterprise. These USE principles will be based on the relevant design requirements for the final scenario. The configuration of the Freeduino based robots is based on these requirements and will be the keystone in the design process.

User

• Control: In case of an emergency the system must have te possibility to be shut down.
• Care: While the robots have interaction with people which are wounded and/or in critical condition. These people need to be handled with care. These people also need to be protected against further harm.
• Robustness: The robots have to be able to operate in destructed areas which means they have to be able to take a beating. Also if they are being operated from a distance there will be no means of repair.

Enterprise

• Simplicity: The beautiful thing about swarm technology is the fact that with a large number of simple robots something big can be achieved. The simpler the individual robot the cheaper the production of it, which makes it an intersting technology for companies to invest in.
• Flexibility: If the robots and software can be used for several scenarios and goals investment will be even more interesting. This means it is of high importance to create a universal software solution for robots which can be used in as much environments as possible. The Freeduino based robots take some of this into account by using track tires.
• Efficiency: The robots need to work efficiently. As area's need to be checked it is important the robots do not check the same twice and do not disturb one another. This also means the robots do not execute tasks which are not necessary which will in turn make sure the robots will last longer. A high efficiency can be achieved using good communication and efficient use of the sensors on each robot.

Large Scale
On the larger scale there is the point of ethical decision making:

• How much priority should two people get over one?
• How much priority should rescuing get over searching?
• Should victims that can easily be saved get priority over victims that are harder to save?
• Should victims that are nearby get priority over victims that are further away?

For these USE aspects, and the incorporation of them into our design on the larger scale, see simulation.

Requirement based configuration

Here the link between the configuration of the Freeduino based robots and the above mentioned requirements will be made:

Track tires

• Track tires will be used mainly to achieve the above mentioned requirement for users Robustness. Since track tires have a much higher stability due to a higher contact area and traction than ordinary tires, especially on rough terrain like in the scenario.
• Another reason why track tires have been chosen is to assure the enterprise requirement Flexibility. Since track tires have a higher adaptability to their terrain and therefor are more adaptable for a bigger range of scenarios, it is preferred to use track tires over ordinary tires.
• The last but not least reason for the track tires, is that due to the user requirement Care. Since these robots depict a larger and more advanced swarm (see scenario) who interact with possible wounded people, this is one of the most important requirements in the design process. Track tires will greatly increase stability when moving along an uneven terrain (like debris) and therefor will reduce any possible harm or distress to the users while being transferred from the disaster struck area.

Speed (actuator)

• One of the requirements for the actuator of the robots is the user requirement Care. Since the speed has a direct connection to the stability of the units, that is if the robots move faster over the debris then there generally will be a bigger disturbance for the wounded. But then again if the robots will move to slow then that would contradict other requirements like the enterprise requirement Efficiency. But since saving people has the biggest priority within the scenario, the user requirement Care will way heavier than the enterprise requirement Efficiency.
• The other requirement for the actuator will be the enterprise requirement Efficiency. The robots will be more efficient when they move around faster, since they will be able to save more people in a shorter timeframe this way. But as stated above this is a matter of prioritizing and therefor an optimum has to be found between these two requirements.

Requirement based choice of Sensors

In Freeduino based robots, it is mentioned with which sensors the swarm robots are equipped. The choice of these sensors are partially based on the USE principles . Here the link between the sensors of the Freeduino based robots and the above mentioned requirements will be made:

Pololu MinIMU-9 Gyro and Accelerometer

• These sensors measure the speed and acceleration of the robot respectively. This is important for the Enterprise principle "efficiency". It is desired that the swarm robots track the premise as efficient and fast as possible, so it's convenient that the robot can keep track of its speed.
• Another reason for the importance of these sensors lies in the user principle "care". A robot should treat the victim with care and make sure it doesn't harm the victim. Speed and acceleration are an important part of this. The user should feel comfortable around the robot. This means the robot has to approach the victim with care, and therefore with limited speed. This way the user will not feel threatened when the swarm robot is approaching.

Distance Measurer using Infrared

• Using infrared, this sensor notices surrounding objects. This is chosen based on the Enterprise principles "efficiency" and "simplicity". The robot can scan notice object that are at a maximum of 800mm away from it. The robot could have been equipped with other distance measure technology, like ultrasound, but since the robot operates in a environment full of ruins and debris, the robot can most likely not look further than about half a meter. A more advanced technology for distance measuring is therefor not needed.

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