PDR Action Items | Yevgeniy | - Vibration tuning
- Tune the housing sitting on its own - the vibration level should "look good" to us
- Hold it in your hand and see how bad it is
- Preflight (post-installation) check
- Look into balancing epoxy instead of bolts
- There exist mathematically optimal approaches to doing this
- Look into how drone props are balanced
- Precession
- Mitigate chance by looking into methods to make sure the wheel isn't canted
- Preflight (post-installation) check by spinning the rocket manually, check whether L is in line with the rocket
- (a - g) cross v gives lateral acceleration, might gate that by a threshold
- Tip-over effects
- Teams in the SAC discord did failure investigations on inertial roll coupling, investigate how related that is
- Motor g-rating (esp if we switch to BLDC)
- Hit it against a table a bunch of times
- Centrifuge? lots of practical problems
- Look into hardening
- Hardening a brushless motor is easier
- Brushed motor is less susceptible to acceleration effects
- combat robotics does not use brushed motors
- Not a lot of experience with BLDC control systems
- Brushless ESCs would probably give good enough response time anyway
- How much will the rocket spin?
- Look at a bunch of flight video
- Spin effects on recovery
- Short-closed failure
- Heavily mitigated by switch to BLDC
- Spin after deployment is not considered that bad
- Watchdogs to watch for spurious outputs
- Watch for very inconsistent sensor outputs
- Shall not spin the motor in the opposite direction of spin
- Configure controller to ignore too-consistent inputs
- Spin effects on ground hit
- Much higher effective velocity
- Not pursuing fancy stuff this year
- Steadily spin-down and lock wheel after deployment
- Lock wheel using ESC braking feature during boost
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