EECE 474 – Group 10: Project Proposal 1 EECE 375/474
FIREFIGHTING
AUTONOMOUS VEHICLE
Submitted by Team 10
John de Vera
Shi Han
Dhruv Raturi
Harshul Srivastava
Wesley Shuen
Miral Abbas
On Sept.28, 2011
University of British Columbia
Faculty of Applied Science Department of Electrical and
Computer Engineering
EECE 474 – Group 10: Project Proposal 2 MAJOR SYSTEM COMPONENTS
The principle goal of this project is to design an autonomous robot that is capable of
navigating through a field, detecting the opponent’s candles and extinguishing them. After
the robot has blown out all the opponent’s candles, it must exit the field through its entry
point. The major system components are shown in Figure 1 below:
Mechanical Design Motors GUI Sensors Microcontroller Path Algorithm Figure 1: Block Diagram showing major system components
EECE 474 – Group 10: Project Proposal 3 CHASSIS DESIGN
In the designing phase of the chassis, the requirements and the constraints were determined.
Based on these factors, the shape, the size and the material of the chassis were chosen. A
major consideration is the size of the robot; we are limited by the specifications given to us,
in which the robot has to be a maximum of 8 inches by 8 inches. In addition to that restraint,
we require that all components fit onto the robot, that it be easy to maneuver, and that it be
relatively easy to build.
On the robot frame, motors, batteries, electronic circuit boards and other necessary
components are mounted. In terms of chassis shape, we considered two designs, triangular
and circular shaped chassis. The first consideration was to design a triangular shaped robot
with 2 back wheels and one front wheel. The triangular shaped chassis has a smaller surface
area to mount components. Also, determining the exact turn distance is difficult.
The second consideration was to design a circular shaped robot, with 2 wheels and 2 ball
bearings. The circular design of the chassis has a good turning radius, which makes it easy to
maneuver. Also there is a relatively even distribution of weight on wheels and ball bearings.
In addition, it is easy to determine how much the robot turned, so as to know the exact
location of robot at all times.
We found that the circular had many more advantages and was better fitting for this project.
The two wheels control forward and back movement, while the 2 ball casters are used to help
with turns.
In terms of the dimensions of the chassis, one idea was to make it 2 layers and just within the
project specifications, so 8inches by 8inches. This arrangement allowed for plenty of space.
However, since one of requirements included ease in maneuvering, we found that decreasing
the horizontal parameters of the chassis and replacing it with a third level allowed for
adequate space, while making it easier to move. Thus, to allow for sufficient space, the
chassis is designed to have three decks, so as to maximize the use of the vertical plane, rather
than the horizontal plane. The exact dimensions have yet to be confirmed, as they depend on
the size of the other project components. A rough sketch is provided in Figure 2 for a
preliminary view of the proposed design.
The components will be divided between the three decks of the robot. The bottom layer will
hold the motors and the power supplies. These components are placed at the bottom due to
the close proximity to the wheels and because they need little adjustments once they are
mounted. The PCB, along with the Arduino microcontroller, occupies the middle deck. The
top level holds the IR sensors and the fan.
EECE 474 – Group 10: Project Proposal 4 Figure 2: Chassis Design
With regards to material, we considered using aluminum, high-density polyethylene (HDPE)
and carbon fiber. Table 1 shows a comparison of the different materials.
Based on table 1 below and our requirements, we chose aluminum. Even though it has the
smallest strength to weight ratio, it is still sufficient for what we need. The machine shop
equipment will be suitable for assembling the chassis. Also since aluminum isn’t very brittle,
we will be able to adjust the 3 decks of the chassis, as we see fit, without worrying about
wearing out the material.
EECE 474 – Group 10: Project Proposal 5 Table 1: Comparison of the different types of material for chassis design
Criteria
Carbon Fibre
Aluminum
Advantages
•
•
High Density
Polyethylene
(HDPE)
Light weight
• Plastic
Used in applications • Light weight
where metal would • Easy to cut, shape
interfere with
and drill
sensors
• Resistant to
Highest strength to
corrosion
weight ratio
Unique- not the
typical material
most groups would
choose
Resistant to
corrosion
Difficult to work
• Considerably
with (ie. Cutting,
brittle:
threading, etc)
components cant
be too tightly
Requires a mold
screwed in
• Bends and flexes
2500
• 40
•
•
Cut using Water Jet
Can’t thread carbon
fibre using machine
shop capabilities
•
•
•
Disadvantages •
•
Approximate
Strength to
Weight Ratio
•
•
Light weight
Resistant to
corrosion
Easy to cut,
shape, drill and
bend
•
Moderate
strength to weight
ratio (specific
strength)
•
220
Cut using Water
Jet
Can be glued
together
Easy to drill
Can screw and
fasten
components
•
Cut using Water
Jet
Easy to drill
Can screw and
fasten
components
Can be bent
Cheapest
Approx. $20 for
12” x 48” sheet
•
•
(kN·m/kg)
Machine Shop •
Related
•
•
•
•
•
Cost
•
•
Most expensive
> $40 for 12” x 48”
sheet
•
•
•
•
•
Moderate
Approx. $30 for
12” x 48” sheet
EECE 474 – Group 10: Project Proposal 6 MOTORS
Based on our research, the most common motors used in robot designs are the DC motors,
Stepper motors, and Servo motors. Each motor offers its own advantages and disadvantages.
Table 2 compares the three motor types in various criteria that we used to select our motor
[1]-[4].
Table 2: Comparison of different types of motors
Criteria
Complexity in
Usage
DC
• Simple to use
• Uses an H-bridge circuit
to change the rotational
direction
Torque
•
Delivers the most torque
of all three motor types
Stepper
• Simple to use
• Plug and play
• Requires motor wires
to be wired to the
stepper motor driver
•
•
•
Accuracy
•
•
•
Efficiency
•
•
Cost
•
Open loop control system
Difficult to command
motor to spin a specific
number of revolutions
Any impedance to
rotation of motor cannot
be detected (no feedback)
•
Average efficiency
because it operates on
continuous power
Current drawn is
proportional to load
Cheapest and most
available to find
•
•
•
•
Delivers less torque
than DC motor
Good low-speed hightorque
Bad high-speed hightorque
Open loop control
system
More accurate than DC
motor because motor is
controlled by a specific
number of pulses
Any impedance to
rotation of motor
cannot be detected (no
feedback)
Low efficiency, motor
draws substantial
power regardless of
load
Generally, more
expensive than DC
motors
Servo
• Most complex to use
because of closed loop
control system
• Four parts: DC motor,
gear reduction unit,
position-sensing
device, and control
circuit
• Delivers less torque
than DC motor
• Good low-speed hightorque
• Good high-speed hightorque
• Closed loop control
system (CLCS)
• CLCS improves
accuracy in the case of
any impedance to
rotation of motor
• If motor is not in
desired position,
feedback is relayed,
and error is corrected
• High efficiency, can
approach 90% at light
loads
• Current drawn is
proportional to load
• Generally, most
expensive of the three
motor types
After looking at the different types of motors, calculations were done in order to determine
what type of motor to use. For this, the required torque, power and current requirements
needed to be calculated first. In order to move our robot on a horizontal surface, its motors
must produce enough torque to overcome any imperfections in the surface or wheels, as well
as friction in the motor itself. Therefore theoretically, a robot does not require much torque to
move purely horizontally. Obviously there will be more friction and resistance in a large
robot than in a small robot, though it is still exponentially less than when a robot encounters
an incline.
EECE 474 – Group 10: Project Proposal 7 An online tool from www.robotshop.com was used to input the operational requirements of
the robot and the following motor parameters were achieved. From the values obtained, we
realised that our motor torque requirements are not high. The speed required to operate the
robot on a horizontal plane for 15 minutes (which is twice the actual operating time of 8
minutes) is only 54 rpm, which can be provided by a servo motor as well. Figure 3, below, is
a screenshot of the online tool used:
Figure 3: Screenshot of Online tool used for motor parameters
After evaluating the above criteria, our group has decided to use servo motors from Parallax.
Refer to Figure 4. Although servo motors are more difficult to use than DC and stepper
motors, the servo motors offer better control, high efficiency, sufficient torque, and they fit
into our budget.
The Parallax (Futaba) Continuous Rotation Servo was selected because it is available in
stock, relatively cheap and versatile with any Pulse-Width Modulation (PWM)
microcontroller. Also, one of our group members has previous experience with this particular
motor. It has the following specifications (see Table 3) [5]:
Table 3: Parallax servo specifications
Parallax (Futaba) Continuous Rotation Servo Specifications
Power Requirements
4-6 V DC
Power Consumption (Idle)
6V 8mA
Communication
Pulse-Width Modulation
EECE 474 – Group 10: Project Proposal 8 Dimensions
Operating Temp Range:
Torque
2.2 x 0.8 x 1.6 in (0.56 x 0.19 x 4.06 cm)
+14 to +122 °F (-10 to +50 °C)
33 oz-in (2.4 kg-cm) at 4.8V
42 oz-in (3.0 kg-cm) at 6V
Figure 4: Parallax servo motor [5]
Keeping in mind the redundancy of the robot system, if in any case, the servo motors fail to
provide smooth operation of the robot, we will use DC motors, which came close second in
our choice of motors. The DC motor we plan to use is the 12V Gear Head Motor by
Lynxmotion. Refer to Figure 5. Its specifications are (see Table 4) [6]:
Figure 5: 12V Gear Head Motor
Table 4: Gear Head motor specifications
Lynxmotion Gear Head Motor Specifications
Reduction Ratio
30:1
Nominal Voltage
12 V
No Load Current
90 mA
Stall Current
1.5 A
Stall Torque
64 oz-in
No Load RPM
200
The motor controller that we plan to use with it is actually an Arduino Compatible Motor
Shield that uses an L298P chip, which allows driving two 12V DC motors with maximum 2A
current. This shield can be directly mounted onto standard Arduino FIO, our choice of
microcontroller.
EECE 474 – Group 10: Project Proposal 9 SENSORS
The sensors are the data gathering centers for our vehicle. We require that the sensors be able
to detect objects such as walls, candles and opponent’s car. Additionally, we require that they
detect IR light emitted by the candles, as well the differences in colour of candles and wall.
Object
Detection
Table 5: Various Sensor Types and Required Tasks
IR Sensor
Ultrasonic
Digital Camera
• Uses
• Scans a wide range.
• Possible with
rangefinder’s
advanced tracking
• Can be affected by
narrow built in
algorithms and
other robot’s
measurements
triangulation
ultrasonic emitters
IR light
Detection
• Can detect IR
light
• No IR light
detection
• Webcams are
equipped to detect
IR light
B/W
Detection
• Uses the
reflectance of the
colour, allow IR
light to reflect and
be detected
• No B/W detection
• Can detect
differences in
colour with coding
Object Detection
Detecting objects and determining their distances is a key feature that is required for this
robot. We chose to use an IR sensor as opposed to an Ultrasonic Sensor or digital camera for
several reasons. Firstly, using a digital camera for distance calculation does not seem very
possible due to its inability to perform triangulation.
Another consideration is the accuracy of these sensors. While the Ultrasonic sensor is
reported to measure distances between 0 and 6.45m, its detection region was much wider,
seeming less precise, in determining the car’s exact location, than the IR sensor’s much
narrower detection region. Also, the ultrasonic sensors were more likely to experience
interference from an opponent’s ultrasonic source. Lastly, the cost is a major consideration.
We found ultrasonic sensors selling at $29.00 while the Sharp IR sensors were only $14.50,
half the cost.
The accuracies for different models of Sharp IR rangefinders are shown below in Figure 6.
The black region shows the distance at which the sensor is not very accurate and the grey
area is the distance that it is accurate. For our purposes using models GP2D120 and
EECE 474 – Group 10: Project Proposal 10 GP2Y0A02YK can provide accurate distance measurements between 4cm (1.5inches) to
150cm (60 inches). As you can see from Figure 7, we plan to use the analog voltage reading
from the IR sensor to detect the different distance readings.
Figure 6: Accuracies of Sharp IR Rangefinders [7]
Figure 7: Analog Voltage vs Distance of Sharp IR Rangefinder [8]
EECE 474 – Group 10: Project Proposal 11 IR Light and Black & White Detection
For determining this design we could either use an IR detector or a digital camera. As seen in
Figure 8 below, we chose to use an IR detector because it can pick up both IR light, given off
by the candle, and white or black found on the candle base. We did not think it was necessary
to use a colour sensor to detect the blue of the wall because wall detection is performed with
the Sharp IR rangefinder. A digital camera can perform the same functions as the IR
detector, but since mounting a whole camera onto the car and transmitting its data wirelessly
to a GPU is too resource intensive, it seemed as an inferior option given the limited time to
complete this project.
Figure 8: Output Voltage vs Distance of White and Gray objects [7]
Unit Cost
$14.50
Quantity
2
$14.50
3
$10.00
$95.00
2
Total Cost
Table 6: Sensors Budget
Name
Part Number
Sharp IR Long
GP2Y0A02YK
Rangefinder
Sharp IR Short
GP2D120
Rangefinder
IR detector
Notes
One front, one left
One front, one left, one
right
Left and Right
EECE 474 – Group 10: Project Proposal 12 MICROCONTROLLER
This section will focus on determining which microcontroller to use for the firefighting robot.
Choosing the right microcontroller to use is very crucial as it is responsible for controlling the
robot on the field. It should also be easily debug-able and given the time constraints to build
the project, the development time for the firmware should be considerably less.
The micro should meet the following specifications:
1. Analog to Digital Converters: Since the sensors that are going to be used are analog
sensors the microcontroller needs to have ADC’s so that it can easily read the sensors
and make the required decisions
2. PWM: In Order to control the motors that make up the drivetrain of the robot it is
important for the microcontroller to have PWM capabilities.
3. GPIO: The microcontroller should also have General Purpose I/O pins to control
elements like the candle blowing mechanism.
4. UART/SPI/I2C: The microcontroller must have some communication capabilities so
that it can communicate with a computer to pass messages back and forth.
5. Clock Speed: The clock speed of the microcontroller directly corresponds to the
number of instructions it can execute in a second. Since this is a timed competition, it
is imperative that the microcontroller be fast and capable of making quick decisions.
Considering the above specifications for the microcontroller required for the project, two
main types of microcontrollers were selected, with the intension of ultimately choosing one
for the robot. The following are the two microcontrollers that were looked into:
1. Coridium SuperPRO: This micro has the following specs.
a. ARM Cortex M3 at 100Mhz
b. 6 12-bit A/D converters
c. 12 Hardware PWM channels
d. 4 UART, 1 SPI, 1 I2C
e. 52 GPIO
f. Programmable in the C programming language.
2. Arduino FIO: this micro has the following specs.
a. ATmega328P at 8Mhz
b. 8 10-bit A/D converters
c. 14 GPIO from which 6 provide PWM
d. 1 UART, 1 SPI, 1 I2C
EECE 474 – Group 10: Project Proposal 13 e. Programmable in the Arduino programming language
For this project we decided to go with the Arduino FIO microcontroller because it meets all
the requirements for this project. Along with that the Arduino has multiple libraries available
on the internet and a lot of documentation that aids in rapid development of the firmware.
Also the FIO provides a built in connector for the XBee wireless module, which we will be
using to facilitate communication between the microcontroller and the computer. Based on
our criteria, the Arduino FIO is the right choice of microcontroller for the scope of this
project.
EECE 474 – Group 10: Project Proposal 14 PATH ALGORITHM
In this project, path algorithms are roughly divided into two types:
1. Based on an overhead camera, a more “mathematical” algorithm.
2. Based on multiple sensors, a more “logical” algorithm.
Table 7, below, describes the advantages and disadvantages of these two types of algorithm:
Table 7: Advantages and disadvantages of the algorithms
Advantages
Disadvantages
Overhead
vision
algorithm
 Less sensor calibration
 Optimize path distance
 Easy to design GUI
 Need to buy a camera
 Complicated image processing
and path planning
Multi-sensor
algorithm
 Straight-forward path
planning
 No image processing
 Cheaper
 Redundant travel path
 Hard to map out all candles
 Lots of sensor calibration
We have proposed three different algorithms to complete the task, two of them are multisensor algorithms and one is an overhead vision algorithm. Given that the camera idea may
not fit within our budget, we decided to use the multi-sensor algorithm as our primary choice.
Multi-sensor algorithm
The foundation of using IR sensors is that they output an analog voltage reading that
corresponds to a certain distance. Once the robot enters the course, it follows the side walls
and goes circularly around the course, the right-side IR sensor will keep reading the distance
to the wall in order to keep the robot on track, while the left-side long range IR sensor will be
responsible for detecting candles in the course. Once a candle is found, the robot will turn 90
degree to the left and then approach to the candle perpendicularly. Color detection, using IR
sensors, and candle extinguishing will then occur before the robot moves backward and
returns to its circular track. After completing the circular path, the robot will exit if all four
candles are extinguished. Otherwise our secondary path-planning algorithm will be initiated,
which will be explained shortly. The reason we will need a secondary path planning is that
the algorithm described above has difficulty reaching to the candles that are trapped in the
middle of the course and surrounded by other candles in all four directions.
This entire process is described in the flow chart (Figure 9) enclosed on the following pages.
EECE 474 – Group 10: Project Proposal 15 Go straight Right sensor read distance to side wall Yes No Turn right Too far? Yes No Wall >3? Too close? Turn left Yes No Front sensor read distance to front wall Wall++; Yes < threshold? Turn left for 90 degree No No Candle found by left sensor? Yes Turn left for 90 degree Go straight No Front sensor read distance to candle < threshold? Yes Right color? Yes No Fan on Exit EECE 474 – Group 10: Project Proposal 16 No Extinguished? Yes Backup Rear sensor read distance to side wall No < threshold? Yes Turn right for 90 degree Exit Yes No Candle < 4 ? Backup to Exit Initiate secondary path planning DONE Figure 9: Multi-­‐ Sensor Algorithm EECE 474 – Group 10: Project Proposal 17 Secondary Path Planning
Once the robot enters the field, it scans the area for objects, using the mounted IR sensors. Of
the objects found, it uses the IR sensor to determine the largest IR source, the closest candle.
It then orientates itself such that the IR source is directly in view of the front sensor. At this
point, the robot should attempt to ascertain the colour of the candle base. If the own candle is
detected the robot will attempt again to determine the colour of the next closest candle,
omitting the candle that was just detected. At any point if the robot moves from its position,
since the last scan to detect the colour of the candle, the long range IR sensor should be
updating in real time its voltage reading as a function of the distance.
Once a certain voltage is reached according to the specifications of the IR sensor data sheet
and our own calibrations, the robot will switch to the short IR rangefinder to detect the
candle. If the colour of its own candle is detected during this time, the robot will stop motion
and rescan the environment ignoring all of the candles that it has already checked. Else, when
the desired candle is detected it continues moving towards the candle. Once the robot is
within the desired distance from candle, it will blow out the candle. It will then wait to check
and confirm that the candle is extinguished. Once complete, the robot rescans the
environment and moves on.
Overhead vision algorithm
An advantage to using an overhead vision algorithm is that if we can locate the target point
and calculate an efficient path from the robot to the target point without hitting any obstacle,
the robot can reach every target including the exit by using said algorithm. The difficulty
arises when it comes to avoiding obstacles. At that point, the concept of alternative target
point must be introduced.
As shown in Figure 10 below, assume the blue circle is our robot, the white circle is a
desired candle, and the black circle is an obstacle, which could be a candle or the opponent’s
robot. We can get the shortest line from the blue circle to the white circle, which is AB, and
then we use AB as a centre line to expand a rectangle whose length is the length of AB, and
the width is larger than the diameter of our robot.
The rectangle will be our test area, which is the black rectangle shown in the graph. As we
can see, there is an obstacle in the test area, or, to the computer’s point of view, there is a ball
of black pixels in that area. In this case, we rotate the test area left using A as the centre until
there is no obstacle in the area (red rectangle). Now we get a line AB1, then we draw a line
from D to AB1, which is perpendicular to AB. This will give us an intersection point C,
which is our alternative target point. Now we can orientate our robot to C (red circle), and
after arriving, B will once again become our target point. Then we will find CB, the shortest
path, and then the robot will do the whole thing again until it finally reaches to the target
candle.
EECE 474 – Group 10: Project Proposal 18 Figure 10: Obstacle Avoidance
As we can see, the test area is always under examination, whether the robot is moving or not.
Once an obstacle is found, the test area will be modified immediately in order to find the
alternative target point. Even if the robot is on the way to an alternative target point, it can
switch to an additional target point if the opponent’s robot pops in.
EECE 474 – Group 10: Project Proposal 19 BATTERY SELECTION
A number of criteria were evaluated in selecting a battery for our robot. Ideally one battery
would be used for the entire duration of the project. This required that the battery be long
lasting and that it be capable of providing sufficient voltage for all components of the robot.
As a result, the Thunder Power RC G6 Pro Power 65C 850mAh 3-Cell/3S 11.1 V lithium
polymer battery (Figure 11) was selected as our primary choice. It has the following
specifications. Refer to Table 8.
Figure 11: Thunder Power lithium polymer battery [9]
Table 8: Battery specifications [9]
Key Specifications
Nominal Value
Supply Voltage
11.1V
Capacity
850mAH
Weight
74 grams
Dimensions
22 x 30 x 63 mm
Connectors
16AWG Wire
Here are the points of why this particular battery was selected:
• 11.1V would meet the specifications of both the 6V Servo motors and 12V DC
motors (back-up)
o A voltage regulator and potentiometer would be used to adjust the voltage to
6V for the servo motors
• A 65C 850mAh rating shows that the battery can supply a high amount of current
o 65 x 850mAh = 55,250 mA or 55.25 Amps
• Light weight, 74 grams or 0.16 pounds
• $32.99 USD with Free Shipping from Saskatchewan
The other consideration was a standard 9V alkaline battery, but this battery tends to have a
lower mAh (capacity) rating and would not be able to provide sufficient voltage in the case
that the 12V DC motors are used.
EECE 474 – Group 10: Project Proposal 20 CANDLE EXTINGUISHING
The project requires the robot to find and extinguish candles that are randomly placed around
the field. It also specifies that the robot must only blow out the opponent’s candles and that
points will be lost for blowing out one’s own candles. This problem can be approached in
multiple ways, but the most optimal solution must account for the above specifications.
It is given that the candles are spaced no less than 2 feet from each other. Along with that it is
known that the best way to extinguish a fire is to deprive its source of oxygen, which in this
case is the wick of the candle. Keeping the above two facts in mind the candle extinguishing
mechanism can be modeled like the following:
Figure 11: Trajectory for extinguishing candle
As seen in figure 11, above, in order to blow out the desired candle and to avoid blowing out
adjacent candles, the mechanism that is responsible for extinguishing the candle must follow
the trajectory described by the image. There are multiple mechanisms that are capable of
extinguishing a candle. Below, three different mechanisms to blow out the candles are
described.
1. Spray of water: A spray bottle full of water can be used to extinguish the candle. But
in order to use this mechanism an elaborate mechanical fixture which uses actuators
that press the spray top will be required. This possesses two major drawbacks; firstly
this is not a very robust system and is prone to failure and secondly the candle may
not be extinguished by only one spray and there is no way of protecting candles in the
vicinity due to the fact that a spray of water is unpredictable in span.
2. Burst of compressed CO2: This mechanism provides a precise burst of CO2 that can
be directed towards the flame to extinguish the fire. But this solution has a couple of
drawbacks as well. The first being that releasing CO2 from the cartridges it is
available in will require an electronically actuated valve and piping system that points
towards the flame. This is a mechanically complicated system. Secondly since the
burst of CO2 is so precise it will be hard to align the robot such that the shooting
nozzle points exactly at the wick of the candle. Since every system encounters noise,
EECE 474 – Group 10: Project Proposal 21 accurately positioning the robot to point at the flame will take too much time and
there are no guarantees that the nozzle will be pointing towards the wick.
3. Propeller Mounted on a DC motor: This mechanism is based on a propeller being
mounted on a small dc motor. This system has a multiple upsides and is ideal for this
application. One, the propeller can be mounted and fixed in any orientation desired.
Looking at the model provided above, the propeller can be mounted such that it blows
air incident to the desired direction assuring that only one candle is extinguished by
the system. Second the system is very easy to control given that turning a dc motor on
and off is trivial when looked from the microcontrollers end. Along with that, since
every system encounters noise and accuracy is hard to achieve, a propeller displaces
air that is within the diameter of the propeller hence providing a buffer zone and
nulling the effect of the noise.
Taking into consideration the drawbacks and advantages related to each method, we chose to
go with the design using a propeller mounted on a dc motor, to extinguish the flame of the
candle.
EECE 474 – Group 10: Project Proposal 22 GUI
Similarly to the path algorithm, we can design the GUI based on a camera or based on multisensors. To map out the field and locate every candle, using an overhead camera will be the
easiest way because the camera will be monitoring the whole field in real time. We can
simply transmit the video to computer, and after simple image processing and calculation, we
can acquire the desired distances, as well as a map of all the objects in the field, which is
updated in real time.
On the other hand, designing GUI based on multi-sensor will be very challenging. We have
proposed an X-Y coordinates method to complete this task. As shown in Figure 12 below, as
the robot travels along the circular path, we can count the rotation of the wheels to see how
far the robot has been going. For example, once the robot enters the field, we begin to count
the distance it has travelled, until the left side sensor detects the first candle, we can acquire
the distance X1, while the sensor will provide us the distance Y1. Now, we will have the
coordinate of the first candle, (X1, Y1). The rest of candles can be located using the same
method. The coordinates can be verified several times noticing that we can also acquire X1 by
subtracting the distance to the right wall, which can be read by the front sensor, from the field
length. Also, every candle can be measured from different directions. It will help us minimize
the deviation.
Figure 12: X-Y coordinates method
The challenges are that this method will output a large amount of data in real time that needs
to be well managed and classified so that we can extract the useful information. In addition, a
big flaw of this method is that the opponent’s robot will significantly interfere with the
measurements since it might be identified as a candle.
We realize that there will be a huge amount of work designing GUI based on multi-sensor.
We will probably consider using a camera if we have spare budget. It will save us a lot of
EECE 474 – Group 10: Project Proposal 23 time so that we can put more effort in optimizing the path planning algorithm. With the mapping data shown on the GUI, we can egress the field through our initial entrance. IMPACT ON SOCIETY
Our robotic car has many applications that can be realized and integrated into modern
society. Firstly, its ability to transmit data wirelessly to a computer allows real time data
gathering, making it safer for humans who require information in either confined or
dangerous places. Some examples of this can include relaying information to the fire
department about where current fires are in a house or even applications with the military
where the rover can attempt to navigate through a minefield and determine the safest path.
Similarly, the sensors of the robot play an integral role in its functionality. Distance detection
can be very beneficial to the disabled, blind or even elderly by helping direct their wheelchair
to move autonomously through a crowd. Additional types of sensors can be placed on the
robot to allow for further functionality, but its ability to navigate around objects and detect
their distances is its primary feature.
In a world where objects are becoming smarter and devices with embedded wireless
communications becomes common, the EECE 474 robot is a concept that is likely to be seen
in the coming future. This kind of device, as well as other engineered devices, will hopefully
inspire students in today’s society to want to become engineers.
EECE 474 – Group 10: Project Proposal 24 BUDGET
The following is a preliminary budget; the reserve money is for any performance
enhancements that may be added to the design at a later date, such as upgrades to
components.
Table 9: Budget of all projected components
Components
Approximate Cost
Chassis: sheet of aluminum
$30
Chassis: extra supplies (ie. bolts/nuts, etc)
$5
Motors: 3 servo motors
$45
Motors: wheels + ball bearings
$5
Sensors: Sharp IR RangeFinder (2 long range and 3 short range)
$75
Sensors: IR detectors (x2)
$20
Microcontroller
$35
Battery
$35
Extinguisher: small motor + gears
$5
PCB
$65
Circuit Components (ie. transistors, resistors, capacitors, LEDs)
$10
XBee Wireless Module
$20
TOTAL
$330
EECE 474 – Group 10: Project Proposal 25 ROLES
John is the team leader and is responsible for managing the team, arranging group meeting,
handing in documents and making sure deadlines are being met. He is also responsible for the
sensors and chassis, along with Miral.
Miral is responsible for the sensors and chassis, along with John.
Dhruv and Shi will be implementing all of the algorithms for the robot systems. They will
receive assistance in implementing each system from the team members responsible for the
hardware of each system.
Harshul and Wesley will be responsible for the motors, motor controllers and wheels.
EECE 474 – Group 10: Project Proposal 26 GANTT CHART
The following Gant chart provides an overview of the projected progress of the project
throughout the term:
Tasks
Administrative planning
Brainstorming high level designs
Developing Proposal
Proposal Powerpoint Presentation Planning
Ordering Parts
Design Chassis on solid works
Familiarize with components/ confirm chassis size
Assemble Chassis
Mount sensors onto robot
Develop/design motor controller and PCB
Order PCB
Test PCB
Integrate PCB circuit with hardware compontents
Voltage to distance testing
Voltage to colour and IR testing
Candle extenguishing testing
Wireless connection
Directional algorithm
Object detection code
Candle line detection / numerical mapping
Secondary object detection code
exit algorithm
GUI: Reading data
GUI: Make it visually appealing
GUI: mapping visually
Commercial
Final Report
08
12
14
SEPTEMBER
15 19 22 23
26
29
30
EECE 474 – Group 10: Project Proposal 27 Tasks
Administrative planning
Brainstorming high level designs
Developing Proposal
Proposal Powerpoint Presentation Planning
Ordering Parts
Design Chassis on solid works
Familiarize with components/ confirm chassis size
Assemble Chassis
Mount sensors onto robot
Develop/design motor controller and PCB
Order PCB
Test PCB
Integrate PCB circuit with hardware compontents
Voltage to distance testing
Voltage to colour and IR testing
Candle extenguishing testing
Wireless connection
Directional algorithm
Object detection code
Candle line detection / numerical mapping
Secondary object detection code
exit algorithm
GUI: Reading data
GUI: Make it visually appealing
GUI: mapping visually
Commercial
Final Report
3
OCTOBER
6 10 13 17 19 20 24 26 27 31
EECE 474 – Group 10: Project Proposal 28 Tasks
Administrative planning
Brainstorming high level designs
Developing Proposal
Proposal Powerpoint Presentation Planning
Ordering Parts
Design Chassis on solid works
Familiarize with components/ confirm chassis size
Assemble Chassis
Mount sensors onto robot
Develop/design motor controller and PCB
Order PCB
Test PCB
Integrate PCB circuit with hardware compontents
Voltage to distance testing
Voltage to colour and IR testing
Candle extenguishing testing
Wireless connection
Directional algorithm
Object detection code
Candle line detection / numerical mapping
Secondary object detection code
exit algorithm
GUI: Reading data
GUI: Make it visually appealing
GUI: mapping visually
Commercial
Final Report
4
7
NOVEMBER
10 14 17 21
23
24
28
30 DEC.2
EECE 474 – Group 10: Project Proposal 29 REFERENCES
[1] "Advantages & Disadvantages of Stepper Motors & DC Servo
Motors." Machinetoolhelp.com. Web. 25 Sept. 2011.
<http://www.machinetoolhelp.com/Automation/systemdesign/stepper_dcservo.html>.
[2] "Electronics Tutorial about DC Motors." Electronics-Tutorials. Web. 25 Sept. 2011.
<http://www.electronics-tutorials.ws/io/io_7.html>.
[3] "Stepper vs Servo Motors." CNC Router Source: The Ultimate Information Resource.
Web. 25 Sept. 2011. <http://www.cncroutersource.com/stepper-vs-servo.html>
[4] McComb, Gordon. The Robot Builder's Bonanza. 2nd ed. McGraw-Hill, 2001. Print.
[5] "Parallax (Futaba) Continuous Rotation Servo." Parallax Inc. Web. 25 Sept. 2011.
<http://www.parallax.com/StoreSearchResults/tabid/768/txtSearch/servo/List/0/SortField/4/P
roductID/102/Default.aspx>.
[6] "Gear Head Motor - 12vdc 30:1 200rpm (6mm Shaft)." Trossen Robotics. Web. 26 Sept.
2011. <http://www.trossenrobotics.com/store/p/4258-Gear-Head-Motor-12vdc-30-1-200rpm6mm-shaft-.aspx>.
[7]“Acroname Quick Comparison Chart for Sharp IR Rangefinders.” Acroname Robotics. Web. 22 Sept. 2011. <http://www.acroname.com/robotics/info/articles/sharp/sharp_compare.pdf>. [8]“Sharp IR Rangers Information.” Acroname Robotics. Web. 22 Sept. 2011. <http://www.acroname.com/robotics/info/articles/sharp/sharp.html>. [9] "Thunder Power RC G6 Pro Power 65C 850mAh 3-Cell/3S 11.1V Lipo
Battery."DraganFLY Innovations Inc. Web. 27 Sept. 2011. <http://www.rctoys.com/rcproducts/TP850-3SPP65.html>.