Project Dachong Bo Liu Department of Physics Dr. A. Antonio Arroyo Dr. Eric M. Schwartz Mike Pridgen Thomas Vermeer University of Florida Department of Electrical and Computer Engineering EEL 5666 Intelligent Machines Design Laboratory

Dachong overview Dachong means big bug. It is a six legged robot. It has six servos for movement. Each pair of legs has a vertical servo for up-n-down movement and a horizontal servo for forward-n-backward movement. It uses an Atmega128 chip on PV Board for controlling. It has a 2x16 LCD display and 4 LEDs for status feedback. It has 3 IR sensors for obstacle avoidance, 3 CdS cells for light intensity detection and a 3-axis accelerometer for acceleration detection.

Mechanical structures of Dachong Main shaft Battery pack Electronics mount IR mount Rear legs assembly Middle legs assembly Front legs assembly

Mechanical structures of Dachong Vertical Servo Vertical gear Leg mount Horizontal gear Horizontal servo Vertical servo mount Vertical shaft Main shaft Pivot support Horizontal servo mount

Sensors on Dachong Bump sensor Accelerometer IR CdS cells

Special sensor: accelerometer Model MMA7260Q from Freescale Semiconductor . Selectable Sensitivity (1.5g/2g/4g/6g) . Low Current Consumption: 500 μA . Sleep Mode: 3 μA . Low Voltage Operation: 2.2 V . 3.6 V . High Sensitivity (800 mV/g @1.5 g) Operation principle . Two surface micromachined capacitive sensing cells (g-cell). . g-cell: a set of beams attached to a movable central mass that move between fixed beams. . Acceleration cause central mass and beams to move, changing the capacitance of 2 back-2-back capacitors. . Measurement of the capacitance difference indicates the acceleration.

Behaviors of Dachong System start Record dark CdS value Click bump switch Record dark CdS value Click bump switch Record bright CdS value Click bump switch Obstacle avoidance walk IR sense obstacles Click bump switch CdS sense bright light Obstacle avoidance turn Level Move to brightest spot Accelerometer

Thank you!