1. Ball Man By Vivek Manoharan TAs: William Dubel and Steven Pickles

2. Problem/Solution

3. Microcontroller Atmega128 SparkFun AVR board 16 MHz ext. crystal

4. Behaviors Locate – CMU Cam to locate tennis ball Ping/Center – Ultrasound to center ball for mechanical arm retrieval Retrieve – Pickup tennis ball Return – CMU cam searches for bright orange

5. CMU Camera Detect contrast level of tennis ball on tennis court Initialization of color required Allows for differently colored tennis balls to be located

6. White Balance Indoors White Balance off

7. White Balance Indoors White balance on

8. Ultrasound Sensors Determine whether objects are on the tennis court If CMU camera RGB values do not match that of tennis ball, obstacle avoidance is initiated If there is a match, retrieval system is called upon

9. Devantech SRF-04’s

10. Mechanical Arm Timing used to determine when to stop “push” Use a high torque DC motor to lower and hoist mechanical arm Places ball into container

11. Mechanical Arm

13. Other Parts

14. Research/Findings CMU resolution is very limited Interaction of independently working behaviors is extremely frustrating

15. Findings

16. Future Work Use a better motor driver for control of all 3 motors (two wheels and one arm) Create a “dropping off” mechanism Allow communication to a remote computer indicating how many balls have been retrieved

17. Conclusion