- Offizieller Beitrag
Der wie ich finde interessantere Teil fehlt aber noch
Alles anzeigenSPOILER ALERT!
Well, that match against Bite Force - Aptyx Designs - Battlebots Team didn't exactly go as planned! We had some electrical gremlins that we didn't solve until right before our next fight, here's a brief story of it all:
We noticed some sparking in the test box coming from the drive pulleys, which we found quite surprising. We looked for shorts, but couldn't find any. We thought, "Eh, what could go wrong?"
Well. When we loaded HyperShock into the BattleBox and did our little showboat test, it started twitching and moving on its own. Whatever was causing the sparks was creating some sort of interference, and the sparks only occurred when the wheels were moving. Since we were already in the arena and the fight was about to start, we decided to YOLO and see what happened. And as we saw, bad things happened. HyperShock was so twitchy and unresponsive to drive that we never had a chance to get a solid hit on Bite Force, and we know what happened after that. After the fight we found some pretty solid damage. There was a chunk missing out of the right weapon disk, the left invertibility horn had a solid slice taken out of it, the right weapon axle retention piece was cracked, and the front left wheel was properly tweaked.
Oh and the top came off.
The top was held on with rubber "wub" mounts. These shock absorbing mounts are great for compression, and comically bad for holding armor on in tension. Lesson: Don't use tiny wubs to hold on armor. The pink boxes that flew out were the battery boxes. Luckily, they came out without damaging the batteries or any connectors. The wiring harness, however, needed a complete redo.
We also learned that the arms locked up as a result of one of the big hits from Bite Force. Upon disassembly we found that all 4 screws had stripped out of the motor front faces and the axles were bent when the motor flailed around inside. This meant we couldn't self-right after the initial hit.
After we got everything back up and running, we still had this mystical sparking problem. After looking closely at the drivetrain, we noticed major sparking was occurring between some floating belt tensioners we'd made and the main belt pulley off of the gearbox. We thought, "Eureka! We found the sparks! Why is it sparking?" After lots of pondering and consulting with other builders and the safety team, we concluded that the tensioners we'd made were building up a static charge from the belts just like a Van der Graaf Generator. We did a small test, and sure enough: when we manually turned the wheels a small electrical potential was created between the chassis and the tensioners. If that was the case, then the sparks would be creating electromagnetic interference, potentially enough to explain the drive issues. So we grounded the tensioners with little grounding cables to the chassis and called it a day, seeing some improvement in responsiveness during testing.
Then our next fight came. As we were rushing to pass pre-fight checks for the next fight, we found that once again we were having the evil sparky-sparks coming from the drivetrain. "But this is impossible! We grounded the tensioners! What else could be wrong?!" 5 minutes before we were supposed to wheel into the arena we realized what was wrong. The power terminals on our Lynch LEM130-95S drive motors are very close to the motor casing. The terminals are threaded for M6 screws, which we didn't have the right length of when we were building HyperShock. But we bought the right length screws to not poke out the back of the terminal and one of us installed them. Well, we all thought one of the other people installed them. We check the terminal screws and, sure enough, one terminal on each motor had a screw that was too long. Once we swapped them out for the CORRECT screws, all our driving issues and apocryphal sparking went away and we rolled straight into the BattleBox to fight... NDA.
TL;DR - The sparks were a symptom of an electrical short between one of the drive motor power terminals and the motor casing, leading to bad electrical joojoo and likely some radio interference. This made it hard to drive, and impossible to compete against a top level robot and driver.