Transcript Midterm Design Review - Purdue College of Engineering

ECE477 MIDTERM DESIGN
REVIEW: TEAM # 6
PLAYS TANKS
Michael Loh, Andres Avila, Andres Castillo, and Sung-Yeon Choi
OUTLINE
• Project Overview
• PSSCs
• Major Components
• Block Diagram
• Packaging Design
• Electrical Schematic
• PCB Layout
• Prototyping Progress
• Software Development Status
• Project Timeline
• Questions
PROJECT OVERVIEW
• Twitch Plays Tanks is a game played between two RC tanks
controlled by either app or live command input from a Twitch
feed. The goal of each player is to score enough hits on his
opponent to win.
• Commands are centrally processed using a Raspberry Pi
• Processed commands are sent to the tanks using the ZigBee
protocol
• Tank will have an IP camera installed for a first-person view to
stream video to a Twitch feed and Android app.
PSSCS
1. An ability to receive and send commands between MSP430 and
Raspberry Pi through ZigBee
2. An ability to communicate between Android app and Raspberry Pi
through Bluetooth
3. An ability to have Raspberry Pi parse commands from Twitch IRC
chat
4. An ability to use IR receiver and transmitter as hit detection
system
5. An ability to have the tank translate sent commands into accurate
motor movement
COMPONENT RASPBERRY PI 2
 Description:
• Microprocessor used as control unit.
• Bridge of communication between Android phones and Twitch to
tank microcontrollers.
• Stream video feed to Twitch stream.
 Relevant Specifications:
• 900 MHz quad-core ARM Cortex-A7 CPU
• 1 GB RAM
• 4 USB ports, 40 GPIO pins
• Ethernet and HDMI ports
• Micro SD card slot
COMPONENT MSP430G2553
 Description:
• Microcontroller used to control tank.
• Controls tank movement, IR hit detection and XBEE
communication with the Raspberry Pi.
 Relevant Specifications:
• 16-Bit RISC Architecture, 16 MHz clock
• 16 KB Flash memory, 512 B RAM
• 16 GPIO pins, 2 USCI pins
• 2 16-Bit timers
• 8 ADC10 channels
COMPONENT XBEE SERIES 1 – 1mW
 Description:
• Zigbee wireless communication interface used for MSP430 and
Raspberry Pi communication.
 Relevant Specifications:
• 3.3 V @ 50mA
• 250 kbps max data rate
• 300 ft. range
• UART communication interface
COMPONENT TSOP38238
 Description:
• IR receiver module used for detecting IR emission from the other
tank.
 Relevant Specifications:
• 38 KHz carrier frequency
• 45 m typical transmission distance
• ±45 ° at half transmission distance
• 2.5 – 5.5 V supply
COMPONENT TSAL6200
 Description:
• IR emitting diode used for signaling the IR receiver from the other
tank.
 Relevant Specifications:
• 200 mA @ 5 V(38 KHz)
• ±17 ° at half intensity
COMPONENT DC MOTOR/H-BRIDGE
 Description:
• Used for controlling tank movement. The possible movements will
be forward, reverse, turn right and turn left.
 Relevant Specifications:
• Motor controlled @ 5 V, 300 mA
• ~ 600 mA stall current
• 5 V H-Bridge operating voltage
COMPONENT LM1117-N
 Description:
• Linear voltage regulators used for converting 7.4 V to ~3 V and ~5 V.
 Relevant Specifications:
• 15 V max input voltage
• 125 °C max junction temperature
• 93 °C/W thermal resistance with heat sink
• 1.08 W max power dissipation
COMPONENT TOUGHSTY IP CAMERA
 Description:
• IP camera connected to each tank. Streams live video to Twitch
feed.
 Relevant Specifications:
• Rechargeable battery built-in
• 50 min battery life
• 25 min/GB memory consumption
• Up to 32 GB SD card
COMPONENT PI CAM MODULE
 Description:
• Camera connected to Raspberry Pi that will stream an eagle eye
view of the arena to Twitch.
 Relevant Specifications:
• Supports 1080p30, 720p60 and 640x480p60/90 video
• Uses dedicated CSI interface in Raspberry Pi 2
COMPONENT NI-MH RC BATTERY
 Description:
• Rechargeable Battery used as tank power supply.
• 4x more capacity than stock tank battery.
 Relevant Specifications:
• 7.2 V/2000 mAh
• 89 x 50 x 16 mm^3
BLOCK DIAGRAM
PACKAGING DESIGN
Tank and PCB
-Tank chassis is premade and taken from an existing RC tank product. PCB will sit
inside the bottom well of the tank chassis
-The NiMH battery pack will sit in a compartment underneath
-The IP camera will glued into a cut-out slot in the front of the tank chassis
Battery pack - 84 x 50 x 15mm
Battery compartment - 100 x 57 x 18mm
PCB - 109 x 75 x 1.6mm
IP camera – 52 x 22 x 22mm
Tank w/o turret - 251 x 148 x 48mm
PACKAGING DESIGN
Arena and Control Module
-Tank arena will be constructed of cardboard and wood. Detachable wood fences
attach to Velcro placements around the cardboard field.
-Cardboard field consists of Velcro circles 6 cm in diameter for placement of simple
field obstacles.
Raspberry Pi will be inside a
basic plastic enclosure
Tank Arena - 130 x 100 x 7cm
Control Module – 12.7 x 6.3 x 5cm
ELECTRICAL SCHEMATIC
OVERVIEW
ELECTRICAL SCHEMATIC
Power Considerations:
- Linear Regulators with
heat sinks to step down
voltage to 5V and 3.3V
- Microcontroller Current
Draw: 500mA
- IR Sensor Current Draw:
500 mA
- Motors Current Draw: 3
motors @ 1 A.
POWER
ELECTRICAL SCHEMATIC
Power Considerations:
- Will control motors @ 5V, 1A
current draw
- Require 5V to operate ICs
H-BRIDGE ICs
ELECTRICAL SCHEMATIC
IR Shooting Mechanism
Considerations:
-
5V Supplied to IR sensor.
Controlled by 2N2222
5V Supplied to IR receivers (active low)
IR Receivers optimal transmission at ±30 degrees. 6 required
for full 360 coverage
- Logic cascaded through 3 NAND Gates and 2 Inverters.
ELECTRICAL SCHEMATIC
Considerations:
- 3.3V required to operate
- Communicates through UART
- Direct connection to microcontroller,
receives data from command center
(Rasp. Pi)
ZigBee XBee MODULE
ELECTRICAL SCHEMATIC
Considerations:
- MSP430 Microcontroller
- 3.3V required to operate
- Brains of the tank. Talks to
motor, IR Sensor, IR
Receiver and Zigbee
MSP430G2553
PCB LAYOUT
OVERVIEW
PCB LAYOUT
POWER
PCB LAYOUT
H-BRIDGES AND MOTORS
PCB LAYOUT
IR RECEIVER & TRANSMITTER
PCB LAYOUT
XBEE MODULE
PCB LAYOUT
MSP430
PROTOTYPING PROGRESS
MSP430:
• IR hit detection system has been implemented successfully.
• Motors have been tested with a power supply, but not
directly with the microcontroller.
• XBEE communication is the next step to be tested once the
programmer arrives.
PROTOTYPING PROGRESS
Pi:
• Libraries needed have been installed.
• One IP camera has been tested and has proprietary software
that doesn’t allow video to be parsed. Therefore, another IP
camera is being tested.
• In the case that the other IP camera can’t be parsed, a
Raspberry Pi Cam Module will be used.
PROTOTYPING PROGRESS
Android App:
• A simple App that displays text has been developed and
tested on actual phone.
• Bluetooth communication between Android App and
Raspberry Pi is in development.
• Video streaming for Android App has not been started.
SOFTWARE DEVELOPMENT STATUS
LEGEND
MSP430
SOFTWARE DEVELOPMENT STATUS
LEGEND
Raspberry Pi
SOFTWARE DEVELOPMENT STATUS
LEGEND
Android App
SOFTWARE DEVELOPMENT STATUS
LEGEND
Others
PROJECT TIMELINE
Week 8
• Finalize and
order PCB
• Finish
preliminary
XBee work
Week 13
• Testing of
complete tank
system
• Finalize Twitch
IRC parser
Week 9
Week 10
Week 11
Week 12
• Build fully
• Finish work on • Complete back- •Integrate Raspi and
functional tank
XBee
end functions of Android app
w/o app
communications
Android app
•Integrate Raspi with
• Verify movement
• Solder PCB
tanks
and firing
components
capabilities
Week 14
• Thanksgiving
Break
Week 15
• Further
integration and
testing
• Completion of
arena and
showcase
preparation
Week 16
• Showcase
Questions?