OmniDirectional Vision System for Mobile Robots Critical Design

Omni-Directional Vision System for Mobile Robots Critical Design Review Denise Fancher Kyle Hoelscher Michael Layton Eric Miller

Omni-directional Mirror Selection Original mirror from Neovision – $290 Light bulb from Lowe’s – two for $3 Budget decreases from $827 to $540 Limited horizon on hemispherical surface Will work for our purposes

Hardware Assembly BOE-Bot assembled and working CMUcam attached and testing is in progress Plans for mounting the light bulb

Software Skeleton Download object coordinates from camera to BOE bot Calculate radius Calculate appropriate movement signal Perform collision detection n If collision eminent calculate new movement signals Issue servo commands

Object Tracking (0, 0) Comfort radius • Adjustable • Determines if bot should approach or back away from the object Movement Determination • X-coord = turn left/right • Magnitude of y-coord determines speed of rotation Comfort radius (72, 40) Radius, r Tracked object location = (x, y) (144, 80)

Obstacle Avoidance Algorithm Considered using vector fields for navigation Currently planning to use a simpler algorithm Uses data from sonar unit and left and right whiskers Case Left Whisker Right Whisker Sonar Interpretation Action 7 1 1 1 Blocked left, right, front Stop, back up 6 1 1 0 Blocked left, right Stop, back up 5 1 0 1 Blocked left, front Stop, turn right 90° 4 1 0 0 Blocked left only Turn right gradually 3 0 1 1 Blocked right, front Stop, turn left 90° 2 0 1 0 Blocked right only Turn left gradually 1 0 0 1 Blocked front only Stop, turn right/left 90° 0 0 Clear Continue in current direction

CMUcam Control Initialization Communication from stamp to camera: n n n Stamp sends SEROUT followed by camera command Stamp sends SERIN to receive data from camera Camera sends data values followed by ACK or NCK

Basic CMUcam Commands L 1 – controls green LED on camera board PM – controls poll mode (multiple or single data packets returned) TC – tracks a color specified by the RGB arguments TW – track window obtains a new color to track from the center of the window RS – resets camera board

Updated Gantt Chart