Knight
Brawlers
Allen Davila Carlos Davila
Will Allen Josh Thames
Group 1
Motivation
• Create a fun gaming system that all group
members would enjoy building
• Include streaming video into the project
• Build something that would provide a first
person experience from the vehicles
• Create something where all members of the
group could keep a functional piece of the
project
Goals
• 2 RC cars controlled by 2 users by their mobile
device’s accelerometer
• On board cameras mounted to the cars that
would provide a live first person view from the
RC cars
• A competition mode that would provide a
competitive game where the cars would fight
each other
• An app that would create a friendly user
interface
Specifications
System
Parameter
Design Spec
Camera
Resolution
VGA 640x480
Camera
Frame Rate
5 fps
Radio
Communication
Wi-Fi 2.4 GHz
Wi-Fi
Range
30 m
Wi-Fi
Data Rate
150 Mbps max
App
User Interface
Android 2.2+
App
Vehicle Control
Tilt
Battery
Life
1 hour
Frame
Scale
1/10th
User
Input
App
Create
Profile
Load Profile
Wifi
System Block Diagram
Raspberry Pi
Camera
Sync Car
Bluetooth
Start Game!
Bumpers
Control Car
End Game and
Report Scores
Motor
H-Bridge
Microcontroller
LEDs
indicating
“Health”
Bumpers
Steering
Motor
User
Input
App
Create
Profile
Load Profile
Wifi
System Block Diagram
Raspberry Pi
Camera
Sync Car
Bluetooth
Start Game!
Bumpers
Control Car
End Game and
Report Scores
Motor
H-Bridge
Microcontroller
LEDs
indicating
“Health”
Bumpers
Steering
Motor
Hit Locations
• Sensors on the rear, right, and left
sides
• Triggered by collisions
Sensors
Piezo Disks Vs. Microswitches
Piezo Disks
Microswitch
Small easy to fit
Small easy to fit
Creates electric pulse on impact
2 state single pole double throw
Price range: 30 cents- 10 dollars
Price range: 90 cents- 5 dollars
High tolerance
High tolerance
Microswitches
• Lever Microswitch for added surface area for
impact
• No debounce circuit needed
• Reverse connection for component reduction
User
Input
App
Create
Profile
Load Profile
Wifi
System Block Diagram
Raspberry Pi
Camera
Sync Car
Bluetooth
Start Game!
Bumpers
Control Car
End Game and
Report Scores
Motor
H-Bridge
Microcontroller
LEDs
indicating
“Health”
Bumpers
Steering
Motor
Scoring System
Full Health
One Hit
Two Hits
LEDs
• Super Bright LED headlights for extra visibility
working at 7000 mcd
• Bright Red LEDs that activate when the car is
idle and turn off when in forward or reverse
motion
• Red, yellow, and green high brightness for top
LED
Forward
Voltage
Forward
Current
Intensity
Headlights
3.3 - 3.6 V
25 mA
7000 mcd
Tail Lights
1.8 – 2.0 V
20 mA
1200 mcd
Top Lights
1.8 – 2.0 V
20 mA
600 mcd
User
Input
App
Create
Profile
Load Profile
Wifi
System Block Diagram
Raspberry Pi
Camera
Sync Car
Bluetooth
Start Game!
Bumpers
Control Car
End Game and
Report Scores
Motor
H-Bridge
Microcontroller
LEDs
indicating
“Health”
Bumpers
Steering
Motor
Camera – Previous
Pros
OmniVision 9655
• Delivers 30 fps at 640x480
VGA Video
• Supports Compressed YCbCr
4:2:2 Format
• Microcontroller Compatible
▫ Fully configurable
• Some Factory Support (STM)
36 mm
27 mm
Camera – Current
OmniVision 5642
Pros
• Supports MJPEG and H.264
hardware compression
• Raspberry Pi Compatible
• Factory Support for stills and
video
• Max 5 MP, 30fps
• Size: 25mm x 20mm x 9mm
• Weight: 3g
Compression? Yes!
Previous
Current
• Real-Time JPEG is optional
(RTJPEG)
▫ Must write in native code
▫ Effort > value
• MJPEG, MPEG-4 etc. not
optional
• Sub sampled RAW images
• MJPEG Supported with
hardware acceleration
• Instead, we are opting for
subsampled images
• Software support
User
Input
App
Create
Profile
Load Profile
Wifi
System Block Diagram
Raspberry Pi
Camera
Sync Car
Bluetooth
Start Game!
Bumpers
Control Car
End Game and
Report Scores
Motor
H-Bridge
Microcontroller
LEDs
indicating
“Health”
Bumpers
Steering
Motor
Wi-Fi Module
Requirements
EW – 7811Un
•
•
•
•
•
•
•
•
•
•
•
•
Simple Configuration
Low Cost
Good Documentation
Modest Data Rate
Modest Range
Low Power
EZmax support
$20
WPS, WPA2
150 Mbps 802.11 b/g/n
Greater Range Than Bluetooth
Raspberry Pi compatible
User
Input
App
Create
Profile
Load Profile
Wifi
System Block Diagram
Raspberry Pi
Camera
Sync Car
Bluetooth
Start Game!
Bumpers
Control Car
End Game and
Report Scores
Motor
H-Bridge
Microcontroller
LEDs
indicating
“Health”
Bumpers
Steering
Motor
Bluetooth MATE Silver
Bluetooth MATE Silver
•
•
•
•
•
Roving Networks Class 2 RN-42
Bluetooth v2.0+EDR
26uA Sleep, 3mA connected, 30 mA transmit
UART data connection to MC
115200 bps
User
Input
App
Create
Profile
Load Profile
Wifi
System Block Diagram
Raspberry Pi
Camera
Sync Car
Bluetooth
Start Game!
Bumpers
Control Car
End Game and
Report Scores
Motor
H-Bridge
Microcontroller
LEDs
indicating
“Health”
Bumpers
Steering
Motor
Motor Control
• DC motors already available on RC car will be
used to reduce project cost.
• 2 DC motors: 1 for steering and 1 for
forward/reverse control.
• Forward/Reverse and Steering motor will be
combined with H-Bridge for function.
H - Bridge Considerations
DVR 8833
L293D
Max Output
10 .8 V
36 V
Peak Output Current
2A
1.2 A
Operating Temp
-40 to 85 C
0 to 70 C
Supply Range
2.7 – 10.8 V
4.5 – 36 V
Control I/F
PWM
PWM
Package Type
Surface Mount mini
Through Hole
L293D H-Bridge Driver
• Two motors per driver.
• Max current output 1.2 A, Max temperature 70 C
degrees Fahrenheit.
• Pulse Width Modulation (PWM) input interface
controls forward/reverse control and right/left
steering.
• Low Power Sleep mode and internal shutdown
functions for over temperature protection.
PWM Control Using H-Bridge
• H-Bridge driver will
use two PWM signals
from the STM32 to
generate Fwd/Rev
and Steering function
of the DC motors.
IN1
IN2
Out1
Out2
Fwd/rev
Motor
Steering
Motor
0
0
Z
Z
Coast
Straight
0
1
L
H
Reverse
Left
1
0
H
L
Forward
Right
1
1
L
L
Brake
-
Motor Control Characters
Motor Function
Character
Slow Forward/ Forward / Fast Forward
A/B/C
Slow Reverse/ Reverse / Fast Reverse
D/E/F
Brake/Right/Left
G/w/y
Medium Right and Slow Forward/Forward/Fast
Forward
(For Left)
H/I/J
(T/U/V)
Hard Right and Slow Forward/Forward/Fast Forward
(For Left)
K/L/M
(W/X/Y)
Medium Right and Slow Reverse/Reverse/Fast Reverse
(For Left)
N/O/P
(Z/a/b)
Hard Right and Slow Reverse/Reverse/Fast Reverse
(For Left)
Q/R/S
(c/d/e)
Remote Control
• Landscape mode
• Direct the RC Car
• Compatible with the newest version of Android
phones and older
Remote Control Requirements
Android Device Must:
 Have Bluetooth Capability
 Contain Accelerometer Sensors
 Have Touch Screen
 Run Android Android 2.2(Froyo)
or higher
Motor Control Using Accelerometer
• RC car will be controlled
by Y and Z coordinates.
• Z direction(into out of
page) will control
Fwd/Rev motor function.
• Y direction will control
left and right steer.
• Sent Through Bluetooth
Handling Accelerometers
Y Axis Calibration
Z Axis Calibration
-Axis’ must be calibrated so that the user can view the device at an
optimal angle. Accelerometers must consider effect due to gravity,
linear acceleration = acceleration - acceleration due to gravity.
Smartphone Operating System
 Android
 Free – No new hardware costs, free SDK, familiar
languages
 Open source platform, easy to learn
Programming
Language
Cost to Develop
Devices Readily
Available?
Familiarity
Android
Java/XML
Free
Yes
Medium
iOS
Objective-C
$99/year
Yes
Medium
Windows
Phone
.NET framework/ Visual
C++/XNA
Free
No
Low
Target APIs 8 (Android 2.2 Froyo and higher),
approximately 99.9% of Android market
Froyo
Version
Code name
API level
Distribution
Ginger-
Bread
2.3-2.7
4.3
Jelly Bean
18
0%
4.2.x
Jelly Bean
17
8.50%
4.1.x
Jelly Bean
16
36.60%
4.0.3–4.0.4
Ice Cream
Sandwich
15
21.70%
3.2
Honeycomb
13
0.10%
3.1
Honeycomb
12
0%
2.3.3–2.3.7
Gingerbread
10
30.70%
2.3–2.3.2
Gingerbread
9
0%
2.2
Froyo
8
2.40%
2.0–2.1
Éclair
7
0%
Honey-
Comb 3.2
Ice
Cream
Sandwich
Jelly
Bean 4.2
Jelly
Bean 4.1
Knight Brawlers App
Power Supply
Current and Voltage Requirements
Component
Voltage Needed (V)
Current Drawn (A)
Raspberry Pi
5
0.5
PCB
3.3
0.16
Discovery Board
5
0.3
Bluetooth Module
5
0.12 max
Wi-Fi Module
Regulated by
Pi
0.15 max
Camera
Regulated by
Raspberry Pi
Unknown but
Negligible
Power Supply
• Rechargeable Batteries
• Nickel Metal Hydride
Remote Control Car
•
•
•
•
18.8 inches Long
5.76 inches Wide
4.8 Inches Tall
Top speed of 2 mph
User
Input
App
Create
Profile
Load Profile
Wifi
System Block Diagram
Raspberry Pi
Camera
Sync Car
Bluetooth
Start Game!
Bumpers
Control Car
End Game and
Report Scores
Motor
H-Bridge
Microcontroller
LEDs
indicating
“Health”
Bumpers
Steering
Motor
Microcontroller
Atmega328
MSP430
STM32F4
AM3359
Dev Board
Arduino Uno
MSP430
STM32F4
Launchpad Discovery
BeagleBone
Black
Speed (MHz)
16
16
168
1 GHz
Language
C, Assembly
C,
Assembly
C, C++,
Assembly
C, C++, C#,
Java
Dev Board Cost
Est. PCB Cost
$35.00
$50.00
$9.99
$50.00
$14.25
$50.00
$45
$100+
PWM support
Yes
Yes
Yes
Yes
Max Temp. (F)
185
185
221
221
Flash Memory
32kB
16kB
1MB
512 MB
Interrupt
Yes
Yes
Yes
Yes
ARM??
No
No
YES! =D
YES!
STM32F407VGT6
• ARM 32 bit Cortex M4F
• PWM for motor control and Plenty of GPIO
available (82)
• Low power modes
• Serial Wire and JTAG interfaces for debugging
• External Interrupt/Event Controller
ST-Link/V2 Debugger & Programmer
• In circuit debugger and programmer for the
STM32 available on Dev. Board
• Supports JTAG/Serial Wire Interface
Schematic Design In Eagle CAD
PCB
Division of Labor
Josh
Will
Allen
Carlos
PCB Design
Motors
Power
Smartphone Interface
Sensors
LED Network/Scoring System
Camera
Wireless Connectivity
All members will lend a hand in any area that may need additional assistance
Budget and Finances
Cost Per Unit ($)
Already Purchased
Units
Cost ($)
Lever Micro Switch Sensors
2.00
9
18.00
RC Cars
40.00
3
120.00
Experimental boards
20.00
3
60.00
Cameras Modules
10.00
3
30.00
Wifi Modules
20.00
3
60.00
Bluetooth Modules
35.00
3
105.00
Raspberry Pi
30.00
3
90.00
PCB
45.00
2
90.00
Power Systems
40.00
3
120.00
Miscellaneous (Wires, LEDs,
Perf Boards, Epoxy, etc.)
Total
NA
NA
200.00
893.00
Progress
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Research
Design
Prototyping
Testing
Project
Completion
Issues
•
•
•
•
Connectivity
Consistency
Soldering
Video Quality
Any Questions?