KorczynskiMcCall

Back to Psych 221 Projects 2013

Active LED Illumination: Wireless Communication

• Active LED Illumination: Wireless Control
• 
  Figure 1. Transmitter
• 
  Figure 2. Receiver

Background

Figure 3

This project idea coincides with several other class projects with regards to experimenting with Active LED Illumination (See References below). Specifically, these experiments involve illuminating objects with high intensity LEDs ( at various levels) to observe and analyze its spectral distribution at high frame rates and various shutter times.

For this project, as further described below, we expect the user to interface our system with the FL3- U3 camera (Shown in Figure 3). We used this camera as a guideline to understand the programming functionality and capability to capture these high frame rate images. This camera serves as a host device that will be programmed to send configuration data (LED module ID # and intensity values) to various LED modules around a room as well as the actual LED Strobe signal to control high density light for high frequencies (in micro-time).

Design Specifications

• Enable multiple programmable light sources for experiments

Figure 4

• Synchronous wireless trigger that can handle 500fps speeds

Figure 5

System Overview

Paragraph describing our system, how it works.....

Design

Transmitter

Receiver

Components and Cost (Bill of Materials)

Transmitter

1. Arduino Pro Mini - $9.95 [product]
2. Parallax Transceiver - $39.95 [product] [datasheet]
3. 74AC157 Multiplexer - $0.15 [product] [datasheet]
4. 3 56Ω resistors
5. 2 3-pin headers (0.1" spacing)
6. 3 Green LEDS - [datasheet]
7. Perfboard - $5.95 [product]

Total Transmitter Cost: $56

Receiver

1. Arduino Uno (or cheaper alternative)- $29.95 [product]
2. Parallax Transceiver - $39.95 [product] [datasheet]
3. 74HC138 Demultiplexer - $0.35 [product] [datasheet]
4. 4 150Ω resistors
5. 1 3-pin header (0.1" spacing)
6. 4 Green LEDS - [datasheet]
7. ArduinoShield - $4.95 [product]

Total Reciever Cost: $75 (or $56 with cheaper Arduino)

Design Methods and Execution

Project Exploration

Looking at Xbees

Communication Protocol Definition with Arduino

Creation of custom data packets How do they interact with one another

Transmitter

sends configuration data 5 times (provides margin for error), then switches to LED trigger mode

Software Error Correction

CRC checking

Testing and Camera Emulator

File:DistanceTest.jpg hola

Results

Achieved Specifications

We were able to confirm: distance and delay (synchronization timing)

Tradeoffs

Speed vs Error: Ex. with Xbees

Conclusions

Here is where you say what your results mean.

References - Resources and related work

• PSYCH W13 hardware groups: [Active-LED Based Illumination (Super Cap Flash System)], [Active LED Based Illumination Control]
• Jameco Electronics Catalog ([1])
• The Importance of Flash Sync Speed [2].

Appendix I - Code

Code

Transmitter: Transmitter code for Arduino

Receiver: Receiver code for Arduino

Camera_Emulator: Camera Emulator

Appendix II - Work partition

Design Planning/Schematics: Allison and Corey

Wireless Transmitter Xbee Testing: Allison and Corey

Final Component Selection: Corey

Firmware and Testing software: Corey

Soldering/Assembly: Allison

Presentation and Wiki: Allison