IMDL Summer 2007: RoBeDeS by David Ladolcetta

Summary Platform Sensors Behaviors

Platform Design 3 layers

Bottom Layer Motors and wheels mounted below Bumper attached to front Servo add-on Board MAVRIC board 3 Battery Packs SONAR JTAG

Middle Layer Drink platform CdS Cells under drink Status LED array

Top Layer Drink stabilizer Pyro Sensor LCD screen

Sensors Bump Sonar CdS PIR

Bump Backup Obstacle Avoidance 3 on front Bumper connecting all three Coat hanger inside Rubber weather stripping 1 on back for reverse Obstacle avoidance

Sonar Main Obstacle avoidance Mounted to minimize middle blind spot and maximize angle of viewing

CdS Drink detector Senses amount of light 3 mounted under middle layer under drinks AD reads ~250 when covered, <100 when uncovered

Pyro Infra Red (PIR) Hacked Wal-Mart Motion detecting night light Senses moving heat Mounted on a sweeping servo to get relative motion from static people Cardboard “Cone” to narrow field of vision

Behaviors Person seeking Obstacle avoidance Person Tracking Drink removal waiting Tray empty

Person seeking behavior The robot moves forward while panning the servo back and forth 120 degrees Continuously checks PIR on AD port 0 for any value above 170 and below 100 on a 0-255 scale. If triggered, enters person tracking mode. Simultaneously checks for Sonar or bump sensors – if triggered, enters obstacle avoidance mode

Obstacle Avoidance Behavior When sonar or bump sensors trigger Stops motors Moves backward for 1 second Turns randomly left or right 90 degrees Moves forward and returns to Person seeking mode

Person Tracking Behavior When pyro triggers meaning a person (or other heat source) is found Reads direction servo is facing and turns platform toward that direction Moves forward and continues sweeping servo If person is within +/- 15 degrees of center keep moving until sonar detects something within 3 in. If person is outside of threshold, robot will adjust platform direction accordingly

Person Tracking (cont’d) If person is not found after 3 full sweeps then robot spins ~400 degrees to re-find person, then adjusts accordingly when found If person is fully lost, returns to Person seeking Once sonar detects person within 3in, stops movement and enters waiting mode

Waiting Behavior Continuously checks CdS cells on AD port 1-3 to detect any removal of a drink Once drink is removed or if no drink is removed after 8 seconds, RoBeDeS turns 180 degrees and returns to person seeking mode If drink is removed and no more drinks remain, enters tray empty mode

Tray Empty Behavior Turns 180 degrees Finds nearest wall Shuts AD off and blinks signifying it needs to be refilled and reset