Smart Lens Robot William McCombie IMDL Spring 2007

Current progress ● Currently have most of the components, including  Servo motor (to drive camera)  Motors  Compass, LCD, etc.  Light sensors ● Currently have some components working  LCD working ● Written code to write text and numbers to LCD  IR sensors working and interfaced with μ C  Compass tested We get signal! Main screen turn on!

To do ● Write behavior algorithms ● Mount components ● Interface motors and servo ● Interpret data from compass board ● Write serial interface for RFID device

Sensors ● IR ● Bump switches ● Compass ● RFID ● Light sensors

IR ● Simple Infrared detectors ● Most accurate within 3-6 inches ● Used for collision avoidance ● If objects are too close, sensor cannot detect them

Bump switches ● Simple on/off switch ● Pressing a switch would activate an interrupt ● When activated, robot will retreat ● At least three bump switches will be used

Compass ● Board with two magnetic sensors oriented orthogonal to each other ● Contains a controller chip ● Interface with either I2C or PWM ● PWM signal consists of high signal with variable length and constant length low signal

RFID ● Radio frequency identification ● Serial interface ● Different readers use different methods of communication ● Half-duplex or full-duplex

Light sensors ● Use of a CDS cell ● CDS acts as a variable resister ● Connected to A/D input ● Colors can be determined by using filters and colored LEDs  Example ● Locate red object ● Navigate along blue line

The camera ● Not a sensor ● Simple point-and-shoot digital camera ● Powered by either two AA batteries or 3.3v input  Could be wired directly to the board if current consumption low enough ● Servo motor can control both power and shutter release by mounting servo between both buttons  Moving servo one way will apply pressure to power switch  Moving servo other direction will apply pressure to shutter release ● Light pressure will allow the camera to focus ● Heavy pressure will release shutter  Servo has adequate power for both functions

Other notes ● The entire setup will be powered by a 9V power supply.  6 rechargeable AA batteries ● Platform designs may differ from original plans  Tripod mount will work, but would require extra weight  Camera tilt function may not work  Instead, mount the camera closer to the ground, to reduce weight ● RFID interface may be reconsidered  Weight and power requirements  Alternative use of simple machine vision using CDS cells ● Camera will be controlled by servo motor