Group 9 Infrared Based Interactive Laser Tag IRILT

Group 9: Infrared Based Interactive Laser Tag (IRILT)

IRILT Team Jason Kazmar Jonathan Stoffer Chad Lau Lets Do This Ali Zaheeruddin

Project Description n n n Use infrared light to provide a safe, projectile-free combat simulator Each team is assigned a different frequency, which, when modulated onto the IR beam, allows players to identify their attackers Players may keep track of their vitals on an LCD screen Appropriate sounds are emitted to correspond with specific actions Upon player death, an RF burst is sent over the playing field to notify all other players When shot, system responds by providing visual and haptic feedback

Project Overview n n n Embedded Atmel ATmega 16 L controls entire system To code the IR for two separate teams, the microcontroller modulates two different frequencies (650 Hz and 1 k. Hz) onto a 38 k. Hz carrier frequency square wave Fully addressable sound chip eases interfacing task System is powered by 4 ‘D’ batteries Removable clip allows user to reload rifle, causing LCD to replenish ammunition supply (full clip = 30 rounds) IR sensors and feedback devices (motors and LEDs) are implemented in a wearable vest and headband, with strategic placement to allow user to be attacked from all angles

Project Motivation n n Create a realistic, yet safe, combat simulator that could be used by the military for training purposes Like military equipment, IRILT equipment must be durable and reliable More cost effective than paintball – hundreds of paintballs need not be purchased for each IRILT use and clothes will not be destroyed More reliable than paintball - IR LEDs will not explode in barrel and thus render rifle useless

Block Diagram - Rifle Antenna IR out Speaker Sound Chip DC Battery Supply RF in/out Microcontroller Removable Team select Clip Trigger Cable to Vest

Block Diagram - Vest Headband with sensors, Motors, and LEDs Sensor Vest Sensor and Motor Port (wired OR) LCD on arm-band Cable to Rifle IR sensors/ demodulators LEDs and Vibrating motors

Constraint analysis/Component Selection Microcontroller – Atmel ATmega 16 L n n n 32 available I/O pins In system programmable FLASH 8 MHz clock Programmable Serial USART Straightforward development interface (Code. Vision. AVR: Programmable in C) Previous experience with Atmel μC’s

Constraint analysis/Component Selection LCD – Crystalfontz CFAH 2004 L-YYB-JP n n 4 x 20 Large viewing area (123. 5 x 43. 0 mm) Small overall package size permits use on wrist Simple to interface

Constraint analysis/Component Selection Sound Chip – ISD 2560 P-ND n n 60 sec recording capacity 3. 4 k. Hz Band Pass Filter Long lasting zero-power message retention (EEPROM): ~100 yrs. Fully addressable to handle multiple messages

Constraint analysis/Component Selection RF Receiver – RXM 433 -LC RF Transmitter – TXM 433 -LC-S n n Low current requirements ¡ Receiver ~5 m. A ¡ Transmitter ~1. 5 m. A FCC Legal 433 MHz Direct Serial Interface No complex antenna requirement

Constraint analysis/Component Selection IR Transmitter – TSAL 6100 n n High-powered IR LED Very short rise and fall time (800 ns) IR Receiver – Panasonic PNA 4602 M n n n 38 k. Hz band pass filter (1 k. Hz 3 d. B rolloff) Insensitive to ambient light Requires no extra parts

Constraint analysis/Component Selection Power Supply -MAX 730 A n n High efficiency 93% - 95% Guaranteed 450 m. A at 6 V input 8 pin package Preselected external component values, so no design work necessary

Patent Liability Analysis n n n Multiple patents have already been granted for laser tag games and laser tag equipment Important existing patents: U. S. Patent # 5, 741, 185, 5, 904, 621, and 6, 261, 180 Patent # 5, 741, 185 – Interactive light-operated toy shooting game ¡ ¡ Toy gun emits coded light signal, which is detected by light sensors Records number of hits and ends the game when appropriate “It is another object of the invention to provide a self-propelled target whose motion is practically unpredictable during a game. ” No literal infringement; no infringement under doctrine of equivalents

Patent Liability Analysis (cont. ) n Patent # 5, 904, 621 – Electronic game with infrared emitter and sensor ¡ ¡ Photodiodes are biased with an inductive current source providing “substantially higher alternating current than direct current circuit impedance” Specific coding placed into IR beams so that shot data may be distinguished from ambient light No literal infringement; infringement under doctrine of equivalents Must pay royalty fees

Patent Liability Analysis (cont. ) n Patent # 6, 261, 180 - Computer programmable interactive toy for a shooting game ¡ ¡ ¡ Has removable data modules for displaying player vitals on LCD and uniquely coding IR transmission Each data module can be reprogrammed by a base station No literal infringement; no infringement under doctrine of equivalents

Reliability and Safety Analysis n n n Microcontroller calculated to have shortest mean time to failure (MTTF) of ~23. 65 years – Limiting Component Mosfets MTTF calculated to be around 41 years All other components found to have well over one hundred years MTTF ¡ ¡ ¡ n DC-DC current mode switching regulator Phototransistors IR emitting diode RF receiving and transmitting modules LCD Panel Criticality Levels ¡ ¡ High – The IRILT unit’s internal components have been damaged or there is possible injury to the user Low – The IRILT unit will not function properly

Reliability and Safety Analysis

Ethical Impact Analysis n Safety ¡ ¡ ¡ n Marketed to Adults ¡ n Make it not look like a real gun Make sure there are no sharp edges that people could hurt themselves on Sealed electronics It is a simulated weapons system that should not be targeted at children Other various warning labels

Environmental Impact Analysis n PCBs ¡ ¡ n PVC piping ¡ ¡ n Can be harmful to the environmental Can be recycled Not biodegradable Like PCBs can be recycled Alkaline Batteries ¡ ¡ Not considered Hazardous waste Can be recycled as well

Packaging Design Considerations Battery Supply IR diode IR Rifle Trigger Removable Clip

Packaging Design and Considerations

Packaging Design and Considerations Fully Suited (front) Fully Suited (back)

Schematic - LCD n n n No power needed for character display—powered through microcontroller Power needed for contrast (controlled through potentiometer) 4 bit data, 3 bit instructions

Schematic - Microcontroller n n USART available for RF transmission and reception Timer input-capture used for IR reception Built in functions for LCD display All floating pins were pulled low to prevent unexpected behavior Atmel ATmega 16 L

Schematic changes - μC

Schematic – Sound Chip

Schematic – Power Supply

Schematic - RF n Copper pour necessary to reduce EMI (electromagnetic interference)

PCB Layout n n n Traces for fast switching signals spaced apart from other lines to prevent EMI RF devices placed far apart from switching voltage regulator Board size = 2. 75” x 11” ¡ n Board must fit inside PVC piping Multiple headers for externally debounced switches

PCB Layout

PCB Layout n Multiplexer unused ¡ ¡ ¡ n Not enough timer input-capture pins for multiple channels Wired-OR all sensors, LEDs, and motors together IR receivers wired directly to headers surrounding microcontroller Audio amplifier unused ¡ Speaker wired directly to sound chip

Software n The software consists of 2 main parts A main loop ¡ 2 Internally controlled interrupts ¡

Software Flow of Control Trigger button yes no Shot fired no Clip Empty yes Fire Shot yes no yes Clip Button Clip Already Updated no Update ammo (ammo = 30) Update ammo On LCD Update Team Frequency Update Team Name on LCD yes no Team Button yes Team Already Changed no yes Check USART Buffer (RF) no Character in Buffer = ‘ 1’ yes no Update LCD with Player 1 Died Message Character in Buffer = ‘ 2’ yes Update LCD with Player 2 Died Message no Update ammo (decrement) Update ammo On LCD Produce Gun Sound

Interrupt Control Flow Call to Hit detect ISR Call to Gun Shot ISR Capture Time Stamp Return Flow Of Control To main loop Turn Timer 2 Output on Timer 2 Output On no yes Calculate Frequency Pulses = 50 Return Flow Of Control To main loop no yes Reinitialize Unit Trigger Button Play Death Sound Transmit Death Signal Update Health Counter (Decrement) Update Health Bar on LCD yes no Health = 0 no Play Hit Sound Update Message On LCD yes Turn Timer 2 Output off

Demonstration n Project Success Criteria ¡ Ability to send, receive, and decode IR signals ¡ Ability to send, receive, and decode RF signals ¡ Ability to displayer vitals in a visual user interface ¡ Ability to generate sounds in response to actions ¡ Ability to provide visual and haptic feedback

Jason Kazmar n n Design Constraint and Analysis Component Selection ¡ ¡ ¡ n n n RF modules IR emitters/detectors Power supply Schematic Populated Board Final Gun Package and Setup

Jonathan Stoffer n n n Ethical and Environmental Analysis Programmed and Debugged all software Component Selection ¡ Microcontroller

Ali Zaheeruddin n n Reliability and Safety Analysis PCB Layout Schematic Packaged Vest and Feedback Sensors Component Selection ¡ ¡ ¡ LCD Panel IR Transmitter Vibrating motors

Chad Lau n Component Selection ¡ ¡ n n IR Receiver Sound Chip Packaging Design and Construction Troubleshooting hardware

What we learned n n n n n That excessive wiring definitely should be avoided How to layout a PCB Floating pins lead to unexpected and confusing results How to create and implement wireless technology (IR and RF) When creating a PCB layout, thicker traces should be used for Vcc and ground All aspects of the design process, technical and professional How to read analyze component data sheets What an RC time constant actually is Whenever ordering a replacement component at the last minute, such as a microcontroller, it’s always a good idea to buy two just in case

IRILTV 2 : Version 2. 0 n n n n Possible implementation of RF in all components of IRILT system—Rifle and vest communicate through RF instead of wires, making IRILT less cumbersome IR grenades, mines—One time, self contained IR emitting devices to increase battlefield tension and difficulty Implement Muzzle Flash Replace IR with directional microwave Team select switch allows for more than two teams Optical scope on rifle “Smart” clip—Clip must be physically exchanged for another when reloading Debouncing switches in software to minimize internal wiring

Questions? IRILT