Projects - User contributions [en]

Projects:2015s1-50 Tracking, Herding and Routing by Autonomous Smart Cars (PG)

2015-08-17T05:34:55Z

A1627992: /* Current Progress */

The aim of this project is to create a system of autonomous smart cars, which will be able
to co-exist and move in an area without collision. Arduino robot vehicles will be used as the
`Smart Cars' due to size and complexity constraints.

[[File:ArduinoRobot.jpg|thumb|alt=The robot being used in place of smart cars.|The Arduino Robot]]

==The Team==
===Team Members===
*Benjamin Riches
*Christopher Bouras
*Michael Cheung
*Tidasa Tennakoon

===Supervisors===
*A/Prof Cheng-Chew Lim
*Prof Peng Shi

== Introduction ==
The basic goal is to be able to demonstrate four smart cars interacting in such a way that
they can create a given formation without colliding with one another. A set of extension goals
devised that incorporate movement in formation, user-defined formations and expansion for
larger numbers of vehicles will also be demonstrated if time permits.
To achieve the proposed environment, two main systems will be created:

1) Movement system

2) Communication system

This project will demonstrate, at a small scale level, a method of which multiple smart
robots can interact with each other, and move based on those interactions. This is a very
important principle as it is the basis for being able to create true automation of devices.
On the other hand, observing this project from the perspective of smart vehicles, it will be
able to demonstrate a starting point for autonomous transportation. Similar systems already
exist, however most use much larger, more powerful computers. The system created in this
project will operate on much less powerful hardware, demonstrating that automation may
not require extensive and expensive computer systems.

==System Overview==
The major design challenge will be making the two systems work together to achieve the
desired result, and the final product is displayed in Figure 1.

[[File:System.png|600px]]

Figure 1: System Overview

==Objectives==
The project has one main objective, with many further extension objectives devised if time
permits. The objective is to create the environment where a command can be sent from a
computer, such as form a line, and from there 4 smart cars will autonomously move to the
required positions to create the formation without colliding with one another. This requires
them to be aware of their initial location on the terrain, the initial locations of all other
smart cars, and the location of all cars whilst in movement. This will require a communica-
tion system between the computer and each robot to be created, and to integrate with the
movement system of the smart cars.
The extension objectives that have been outlined include; Making the smart cars move in
formation, making the smart cars move into a user-defined formation (via computer appli-
cation) and allowing the system to be expandable for many more smart cars (up to 10).

== Project Details ==
===The Robot===

To implement the smart cars we will be using an existing Arduino robot that is readily
available on the market. This makes it easier for us as we wont have to design and construct the hardware of the smart car as this would veer away from
the scope of our project.
The Arduino robot platform has the following features:

• ATmega32u4 microprocessor, which has a reasonable amount of computational power
and on-board memory, which is vital for our calculations.

• Pre built movement system, which includes motors, motor controllers, wheels and
gearboxes.

• Additional on-board memory space, to allow more code to be stored.

• Compass sensor and multiple extension slots to allow additional sensors to be added.

===Grid/Initial Position System===
In order for the smart cars to know their current positions without the need to use GPS
coordinates, we will need to establish a grid system in the operational terrain, which is approximately a 4m by 4m or 5m
by 5m area. The smart car will then be using a coordinate in the grid system to determine
their current location.

The process will be to first establish the grid system using a designated boundary set out by
physical markers, then using the established grid system the initial positions of the smart
cars can be calculated and communicated to them. This can done in various ways, for this project we will be mainly focusing on image processing.

The image recognition process will be done be using a HD webcam and camera mount so
that the camera has a view of the entire operational terrain. To establish the grid systems and initial positions we will place coloured markers in four
corners of the terrain and program the smart cars to display a unique colour on their LCD
screens, this is so the boundaries and smart cars can be more easily distinguished to the
image recognition algorithm. The webcam will the take a single HD photo of the terrain
and send it to the computer control unit.

The computer control unit will then use image recognition algorithm in its existing system
to first determine the boundaries to create a grid system, then to recognise the smart cars
and using the grid, determine the initial positions of the smart cars. This information will
then be sent out to the smart cars using Wi-Fi.

[[File:ImageRecognition.png|ImageRecognition.png||700px]]

Figure 2: Image Processing Technique

===Smart Car Control System===
The behaviour and movement of the smart car will be determined by the smart car control
system. Each smart car will use this system independently of the other robots. This system
consists of three subsystems.

'''1. Basic Movement System (BMS)'''

The first subsystem that will need to be implemented is the basic movement system (BMS),
the BMS handles any physical moment the smart car will need to make, this consists of
moving in a straight line forwards and backwards, performing a 90 degree turn, performing
a curved turn and stopping. The Arduino robot already comes pre-programmed with a library to help perform these
movements; however code will need to be written in conjunction with this library in order
for the robot perform these given movements provided previously.

'''2. Routing System'''

The routing system uses behaviour algorithms and additionally data inputs to calculate an
optimal route for the smart car to take to avoid other smart cars and obstacles. This route
will then be translated to the BMS which will physically move the smart to along that route.
The routing system works by first getting a command and coordinate from the computer
control unit. Knowing its goal the routing system will then give the current location and the real time
locations of the other smart cars to the behaviour algorithm. The behaviour algorithm will
then use this information to determine which route to the destination coordinate the smart
car must take to avoid the other smart cars and any obstacles on the way.

The routing system will be continually monitoring the location of itself and the other smart
cars around it, if however a smart car gets too close, the routing system will then need to re
calculate a route to avoid a collision, this may mean waiting for another smart car to pass
or reversing and changing direction. The appropriate decision will be determined by the
behaviour algorithm.

'''3. Sensory System'''

Many of the systems described above rely on the use of various sensors to provide the
appropriate information to perform a task. The sensory system has two roles the first is to
provide raw sensor data to various systems and the second is the make calculations of its
own using the sensors and giving that information to other systems.

The sensory system provides the raw sensor data of the compass, the compass will provide
the current direction the smart car is facing and this information will be given to the BMS,
the BMS is reliant on this information so that it can move the smart car in a certain direction
or make a turn. The sensory system also provides calculated data using various sensors, the main information
being the current location of the smart car.

===Communication System===

The communication system is vital part of the object avoidance system it provides the
necessary information to be transferred amongst the smart cars and the computer control
unit. We will be using Wi-Fi as the form of communication we have chosen this for the
following reasons
• Wi-Fi shields are relatively cheap and easily adapted on to the Arduino robot platforms;
they are come with extensive pre-built libraries to assists with programming.

• Wi-Fi provides the ability to broadcast information, this means multiple devices can
receive the information simultaneously.

• Wi-Fi can be made secure to prevent interference from external sources.

• Wi-Fi shields have an approximate range of 100m indoors which is more than adequate
for what we require.

There will be two types of communication in the object avoidance systems.

'''1. Communication Between Smart Cars'''

In order for the routing system to determine the optimal route for the smart car to take,
it must first know the positions of all the other smart cars in the area. This information is
found from the communication system. When a smart car moves, the sensory system described previously will determine the new
position of the smart car, this information will then be broadcasted to all the other smart
cars in the area using the Wi-Fi communication system. The receiving smart robot will
be constantly checking for new coordinates on the Wi-Fi communication network, when
it determines that another smart car has moved it will save its new position in onboard
memory. Therefore, each smart car will have stored the current position of all the other smart cars
in the area and will use this information to avoid collisions.

'''2. Communication Between Smart Cars and Computer Control Unit'''

The computer control unit also plays an important role in the communication network. As
previously discussed the smart cars will be communicating their positions to each other,
however they will also be communicating their position to the computer control unit as well,
by doing this the computer control unit can know where all the smart cars are at all times,
this has a lot of uses which will be discussed in the next section.
Additionally, the computer control unit will need to send information to the smart cars
individually or all at once. This includes issuing commands to the smart cars, giving out
initial positions in the case of image recognition being used or issuing an emergency stop.

===Computer Control Unit (CCU)===

The computer control unit will act as the central command of the smart cars, its roles
include:

'''1. Issuing Tasks to the Smart Cars'''

The CCU program will have a range of predefined requests the smart cars can perform such
as make a shape formation. When the user picks one of these requests the CCU program will
first determine the positions each smart car must go to, next it sends out this information
plus a status of the task to all the smart cars. For example go to this position and create a
square formation.

'''2. Up To Date View of the Grid'''

The CCU will also keep an up to date map showing the current positions of all the smart
cars in the grid, this information helps the CCU determine the positions the smart cars must
go to, to perform a task.
Additionally, other than to give the user a graphical representation of where the smart cars
are on the grid, there will be another map that the user can interact with. This map will
initially show robot markers corresponding to their current locations. The user will then be
able to drag and drop these markers on the map, which will then make the actual robot
move to that position in the grid. By doing this, user will be able to create custom routes
for the robots apart from the pre-defined formations.

'''3. Emergency Stop'''

To encourage the safety of the project we will have an emergency stop command on the
CCU, if the user initiates this command, the CCU will issue an emergency stop to all the
smart cars regardless of there current positions or movements. This is to ensure if an error
was to occur there was minimal damage to the systems.

== Resources ==

Projects:2015s1-50 Tracking, Herding and Routing by Autonomous Smart Cars (PG)

2015-08-17T05:32:08Z

A1627992: