1 / 27

ECE 477 Design Review Team 5  Fall 2009

ECE 477 Design Review Team 5  Fall 2009. Ben Carter – Jacqui Dickerson – Ian Oliver – Dennis Lee. Outline. Project overview Project-specific success criteria Block diagram Component selection rationale Packaging design Schematic and theory of operation PCB layout

astro
Download Presentation

ECE 477 Design Review Team 5  Fall 2009

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ECE 477 Design Review Team 5  Fall 2009 Ben Carter – Jacqui Dickerson – Ian Oliver – Dennis Lee

  2. Outline • Project overview • Project-specific success criteria • Block diagram • Component selection rationale • Packaging design • Schematic and theory of operation • PCB layout • Software design/development status • Project completion timeline • Questions / discussion

  3. Project Overview • Next generation communication system for vehicles • Simple, real-time visual communication • Multi-touch input • Driver’s gestures produce an output on LEDs around the perimeter of a car • Color-coded messages • Tri-color LEDs produce blue, green, yellow, orange, and red outputs

  4. Project-Specific Success Criteria • 1. The ability to determine direction of a finger sweep on a touch pad array. • 2. The ability to determine the number of fingers used on a touch pad array. • 3. The ability to produce at least two meaningful LED patterns. • 4. The ability to determine force of acceleration on a car. • 5. The ability to wirelessly transmit data from the multi-touch signal processor to the LED cluster controllers

  5. 30 Capacitive Touch Inputs 30 Capacitive Touch Inputs 30 Capacitive Touch Inputs 30 Capacitive Touch Inputs 30 30 30 30 5 More CapSense Controller 0 CapSense Controller 1 CapSense Controller 7 CapSense Controller 8 I2C Microcontroller/DSP (Gesture Recognition) I2C LED Driver 0 LED Driver 3 UART Tx 2 more 15 15 RF Transmitter 5 tricolor LEDs 5 tricolor LEDs RF Communication @ 315MHz RF Receiver 0V – 5V analog UART Rx Microcontroller 0 (LED Control) Accelerometer I2C LED Driver 0 LED Driver 13 12 more 15 15 5 tricolor LEDs 5 tricolor LEDs

  6. Component Selection Rationale • dsPIC33FJ256MC710 • Required a lot of RAM & moderate Flash • Availability w/ many suppliers • PIC18F2525 • Required I2C interfacing & sizeable Flash • dsPIC chosen; staying w/ same family • LED Drivers (TLC59116) • Required 15 PWM channels to control 5 tri-color LEDs • Ability to control up to 16 PWM channels

  7. Component Selection Rationale • RF Transmitter/Receiver (MO-SAWR-AS315M/MO-RX3400-A315M) • Required 315MHz • Provides up to 100m of transmission • Accelerometer (MMA1270EG) • Required 2.5g over 3 axes at 5V • SOIC packaging for ease of soldering • Capacitive Touch Input Controllers (CY8C20666) • Required multiple touches to be realized • Donated by Purdue Alum & Cypress FAE

  8. Packaging Design Constraints • Will not be demonstrating on a full size vehicle • Large RC car will house one LED Output Cluster • User Interface Module will be exterior to car, powered by an AC wall wart • Full size design would consist of several LED Output Clusters, weatherproofing, and a scheme for mounting the User Interface Module to a steering wheel

  9. Packaging Design – User Interface Module • 8”x8”x1-1/2” • *variable • 20 user feedback LEDs replicate LED output on RC car • Front will be denoted with a print of a black & white top-view sketch of a car • 5”x6” capacitive touch area is uncovered PCB • External 2” antenna for RF transmission to RC car

  10. Packaging Design - LED Output Vehicle • 32”x12”x10” • 12 LEDs for front/back • 23 LEDs for sides • =>70 tricolor LEDs • ~1LED per 1.5” • LEDs mounted on 5 apiece on 14 PCBs • LED Panel PCBs mounted on inside of car’s exterior plastic • Holes will need to be drilled through car’s exterior for LEDs to show through • LEDs will extend ~3/4” off PCB, so will be able to flex and fit through

  11. Schematic/Theory of Operation • duplicate this slide as necessary for each major block of your design

  12. Schematic/Theory of Operation • Capacitive sensor is a pair of plates/electrodes • There is also capacitance between finger and electrodes • A sensor detects change in capacitance when finger is present

  13. Schematic/Theory of Operation • Capacitive buttons are on one side of the board • The microcontroller (PSoC) is on the other side • A plastic/glass overlay (1-5mm thick) covers buttons

  14. Schematic/Theory of Operation • The capacitive sensing microcontroller is the PSoC • Each PSoC can scan buttons and communicate over I2C • Our PSoC will communicate with a DSP to process inputs

  15. Schematic/Theory of Operation • Flow of input to output: • CapSense microcontroller (PSoC) reads input from buttons – 9 PSoCs to sense 120 buttons total • DSP (dsPIC) reads PSoCs to interpret input, sends commands to LED controller wirelessly • LED controller (PIC18) coordinates LED drivers to produce output patterns

  16. RST to PSoCs dsPIC I2C to PSoCs and TLC RF Tx to PIC18

  17. PCB Layout – TLC Board • Main Components • 5 LEDs and a single TLC driver chip • Other Components • 5 Resistors, 5 Headers, 1 Capacitor • 0.5” x 5” • Tight space required careful routing

  18. PCB Layout – TLC Board

  19. PCB Layout – PIC18 Board Main Components PIC18, RF Receiver, Power Supply Other Components Switch, 18 Headers, 3 Resistors, 4 Capacitors, 1 Inductor, and 1 Diode 1.4” x 5” Plenty of space allowed for easy routing and the ability to actually minimize the area of the board

  20. PCB Layout – PIC18 Board

  21. PCB Layout – dsPic Board Main Components dsPIC, RF Transmitter, Power Supply Other Components 10 Capacitors, 16 Resistors, 1 Switch, and 17 Headers 2” x 7” section of the larger User Interface Board Lots of space allowed for large heat sink and ease of routing

  22. PCB Layout – dsPic Board

  23. PCB Layout – MultiTouch Board Main Components 1 Cypress PSOC chip and 30 CapSense Pads Other Components 34 Resistors, 2 Headers, 1 Capacitor, and 1 OR gate 5” x 6” Section of the larger User Interface Board Via on each CapSense pad made routing very difficult

  24. PCB Layout – MultiTouch Board

  25. Software Design/Development Status • PIC18F(LED Output Controller) • LED Output Coordination • Establishing Timer0 interrupts, I2C interface • dsPIC33F(Multiple Touch Processor) • Finger Count Detection • Area vs. discrete contacts • Direction Vector Calculation • Track angle of finger swipe • CY8C(CapSense Controller) • Activation of CapSense block, record data, then communication of data over I2C

  26. Project Completion Timeline

  27. Questions / Discussion

More Related