Re: acceleration problem
I don't have an EV3 in front of me to test, but I think I see a couple problems:
In the version of the loop posted by switch, the Move Block is set to 10 degrees of rotation, then coast. I presume that the intent is to increase the motor power every 10 degrees of motor rotation. This should give a smooth acceleration. But apparently this isn't working correctly. It's not clear why one motor would be running at twice the speed of the other, but this is likely caused by an unexpected interaction of the Move Block's error correcting algorithm with being reset every 10 degrees.
One other problem is that the loop is set to 100 counts, which would make the motor turn 1000 degrees before the loop exits. But this is probably just a test, so you can fix that.
The revised version posted by GWhizNonKid has a problem that there is no delay in the loop, so it will set the motor to 25 (init to 15, then add 10 before setting), then immediately set it to 35 and 45 before the motor has even started turning. Perhaps some sort of delay during the acceleration would be helpful.
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