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Unread 26-02-2016, 23:19
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Monochron Monochron is offline
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Re: Diagnosing Belt Skip Under Load

We are planning to increase our driving and driven pulley size and also increase their tension slightly based on gpetilli's recommendation. I would also like to look into better programmatic control but so far we haven't gotten a solution that we are happy with.

We need PID control so that we can hold the arm in position to intake balls, but a ramp function tends to cause the I term to accumulate too much and we end up with massive oscillation. We also looked for PID values that would reduce acceleration/deceleration but we weren't able to eliminate steady state error.

Does anyone have a good recommendation for a way to maintain relatively accurate control over the arm but reduce acceleration and deceleration forces? Motion profiling is certainly a possibility, though tuning it without a practice bot is going to be a big challenge for us.