Embedded Motion Control 2018 Group 5

Group information

Name	Student number	E-mail
M.J.W. Verhagen	0810317	m dot j dot w dot verhagen at student dot tue dot nl
L.W. Feenstra	0847751	l dot w dot feenstra at student dot tue dot nl
A.J.J. Steinbusch	0903892	a dot j dot j dot steinbusch at student dot tue dot nl
J.T. Galen	0897620	j dot t dot v dot galen at student dot tue dot nl

Introduction

This project is part of the course Embedded Motion Control in which software is developed and applied to control an autonomous robot in real-life. The project consists of two challenges: the Escape Room challenge and the Hospital challenge. The Escape Room challenge will be an intermediate challenge that serves as preparation of the final challenge which is the Hospital challenge. In both challenges a robot has to fulfill a task autonomously. To begin with, an initial design is made in which the requirements and specifications of the two challenges are touched upon, functions that the software will be divided in, the components of the robot that will be used with their specifications and the interfaces that will be used.

Initial Design

Requirements

General requirements that hold for both challenges are:

• PICO must move autonomously
• PICO cannot bump into walls
• PICO gets 2 trails to perform the entire task
• PICO cannot stand still for longer than 30 seconds
• The total time limit for PICO to accomplish its tasks is 5 minutes
• The challenges must be finished as quick as possible
• PICO should have a minimal distance from the wall of 25 cm from its center point
• The software must be easy to set-up

Additional requirements concerning the Escape Room challenge are:

• Find the corridor

Additional requirements concerning the Hospital challenge are:

• PICO has to explore the rooms and build a map
• It has to be able to park backwards to the wall behind the starting position
• PICO must be able to recognize a change in the map and by means of that find an object in one of the rooms
• PICO must stop and stand still close to the object after finding it

Functions

Task:

Skill:

• Decision making
• Object avoidance
• Path planning
• Object recognition
  • Detect exit
  • Detect wall
  • Detect corner
  • Detect object
• Localisation
• Mapping

Action:

• Measurement:
  • Read encoder
  • Read LRF
• Move:
  • Stop
  • Translate:
    • Left, Right, Back, Straight ahead or x and y direction
  • Rotate:
    • Direction and angle or +/- 90/180/360 degrees
• Shut down

World model: The world model contains information about the initial position, the current position, the position of the walls, exits and corridors that PICO encountered. It will also contain a function that communicates with functions in other models.

Components

The robot that will be used in this project is PICO which is a telepresence robot from Aldebaran. PICO moves on omni-wheels so that it can move in all directions and it can rotate along the z-axis. It contains a Laser Range Finder (LRF) to detect the walls and objects. Also, PICO is provided with wheel encoders to estimate the change in position.

PICO runs on an Intel I7 on Ubuntu 16.04. A software layer has been created onto the Robot Operating System to simplify the use. The software of this project will be programmed in C++.

Specifications

Specifications of PICO:

• The maximum translational speed is 0.5 m/s and the maximum rotational speed is 1.2 rad/s
• PICO is approximately 40 cm wide
• Laser Range Finder has a range of -2.35619 to 2.35619 rad with 1081 points

Specifications concerning the Escape Room challenge are:

• PICO has escaped the room when the entire rear wheel is across the finish line
• The shape of the room is rectangular and the dimensions of the room are to be revealed at the start of the challenge
• The start position of PICO will be at a random position in the room
• The orientation of the corridor will be approximately perpendicular to the wall an the wall on the far end of the corridor will be open
• The walls might not be perfectly straight, nor perfectly perpendicular and parallel to other walls
• The width of the corridor will be in between 0.5 and 1.5 meters
• The finish line will be more than 3 meters into the corridor to give PICO so more time to align with the walls of the corridor

Specifications concerning the Hospital challenge are:

• PICO's starting position will be in the hallway