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 An ability to receive and send commands between MSP430 and Raspberry Pi through ZigBee An ability to communicate between Android app and Raspberry Pi through Bluetooth An ability to have Raspberry Pi parse commands from Twitch IRC chat An ability to use IR receiver and transmitter as hit detection system 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: Relevant Specifications: 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: Relevant Specifications: 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: Relevant Specifications: 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: Relevant Specifications: 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. Tank Arena - 130 x 100 x 7cm Control Module – 12.7 x 6.3 x 5cm Raspberry Pi will be inside a basic plastic enclosure

Electrical Schematic Overview

Electrical Schematic POWER 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.

Electrical Schematic H-Bridge ICs Power Considerations: Will control motors @ 5V, 1A current draw Require 5V to operate 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 ZigBee Xbee module Considerations: 3.3V required to operate Communicates through UART Direct connection to microcontroller, receives data from command center (Rasp. Pi)

Electrical Schematic MSP430G2553 Considerations: MSP430 Microcontroller 3.3V required to operate Brains of the tank. Talks to motor, IR Sensor, IR Receiver and Zigbee

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 Finalize and order PCB Finish preliminary XBee work Week 8 Week 9 Week 10 Week 11 Week 12 Finalize and order PCB Finish preliminary XBee work Build fully functional tank w/o app Verify movement and firing capabilities Finish work on XBee communications Complete back-end functions of Android app Solder PCB components Integrate Raspi and Android app Integrate Raspi with tanks   Week 13 Week 14 Week 15 Week 16 Testing of complete tank system Finalize Twitch IRC parser Thanksgiving Break Further integration and testing Completion of arena and showcase preparation Showcase

Questions?