A Deep Dive into Juggling Robot's Development and Challenges
0:00:29 Introduction: The stream marks the beginning of the 2025 development, sharing exciting updates and reflecting on holiday progress.
0:01:14 Marker Caps Solution: Surprisingly, black marker caps deter the cats from interfering with the tracking markers on the robot's base, solving a previous issue with white caps.
0:02:43 Cable Issue: A loose yellow wire in one of the robot's legs caused unexpected malfunctions, highlighting a critical error handling oversight.
0:05:11 Error Handling Improvement: The presenter significantly revamped the error handling system, allowing multiple errors to be stored and addressed, improving robustness.
0:07:06 Unforeseen Issue: Despite improvements, the specific cable issue might still not be detectable by the system, as it doesn't trigger an error in the current sequence.
0:08:34 Catching Milestone: The robot successfully caught a ball, albeit with a lenient definition of "catch," demonstrating progress in tracking and motion.
0:09:29 Hand Motion Issue: The hand's movement was intentionally restricted during testing, focusing on tracking and robot motion, but it revealed issues like the hand not moving as expected.
0:10:52 Coordinate System Discrepancy: A 90-degree difference between the tracking software's coordinate system and the robot's internal system caused significant movement errors, later resolved by rotating the tracking data.
0:14:03 Leg Collapse Issue: One leg consistently collapsed during catch attempts, potentially due to torque limits or platform tilt, requiring further investigation.
0:18:15 Ball Tracking Problem: The tracking system occasionally registers one ball as two due to occlusion by the hand's carbon fiber tubes, a persistent challenge with no easy solution.
0:23:45 Boot Sequence Simplification: The robot's boot sequence was streamlined, eliminating unnecessary complexity and improving overall system behavior.
0:26:33 Data Bagging Implementation: The ROS network was configured to record ("bag") each session, capturing valuable data for analysis and debugging, using PlotJuggler for visualization.
0:35:01 Hand Control Update: The hand control system was updated to use a single message instead of three, simplifying commands and potentially improving responsiveness.
0:38:53 O-Drive Gain Issue: The presenter encountered difficulties translating theoretical spring-damper system parameters into appropriate O-Drive gain values, leading to unexpected hand behavior.
0:50:53 Testing Rig Challenges: The custom-built testing rig faced issues with string tangling due to the O-Drive's unidirectional control, limiting its effectiveness.
0:56:22 Motor Spool Problem: The motor spool on the robot's hand unscrewed itself during testing, potentially due to excessive force or a design flaw, requiring a future solution.
0:59:33 Catching Strategy: The presenter discussed the importance of passive catching, aiming for a compliant hand that can absorb the ball's impact without precise velocity matching.
1:11:53 Spring-Damper System Modeling: A spring-damper model was developed to simulate the desired hand behavior during catching, but translating theoretical parameters to O-Drive gains proved challenging.
1:20:38 Inconsistent Behavior: The robot's hand exhibited inconsistent behavior during testing, with settings seemingly affecting each other in unpredictable ways, hindering progress.
1:30:33 Future Plans: The presenter outlined plans to continue refining the catching mechanism, improve data logging, and address the identified issues, aiming for a robust and reliable juggling robot.