To reduce the jerkiness at start, just reduce the power on the large motors.
If you keep it at 100 power, it starts with a big jerk. You could do 30 and then it is better.

If that is too slow and you need more speed........ try cascading a 30 power block for  half a rotation followed with a 100 power block <<just a wild guess, may or may not work

Crunchy? Maybe the motors are going bad?
Try testing the motors by running the motors from the EV3 brick itself. If they sound different, maybe there is some kind of loop or something in the program which is making the motor "chatter"...meaning power being applied on and off in very fast succession.



Sincerely,

Rajeev Mehra


 

From: First Lego League in Virginia and DC <[log in to unmask]> on behalf of Shanti <[log in to unmask]>
Sent: Sunday, November 17, 2019 11:52 PM
To: [log in to unmask] <[log in to unmask]>
Subject: Re: [VADCFLL-L] FLL Fairfax Drift
 
Hi Chris,
How were you able to fix?

Also our large motors making crunchy sounds while running, when compared to others teams robots that run very smooth.
Is there a factory reset kind of a thing that we can do on them.?
Also how to resolve the jerkiness when the robot starts from a stop.?

>Thank you to all of the coaches that responded to this post.  We were able to fix the drift.

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