pic: Shifting Module for Drivetrain Concept

[lemiant]

Originally Posted by crazyStone

I thought the same thing that they should be the same speed, I was just told by some members of my team that the difference in preformance is great enough between 2 cims that a noticeable amount of preformance is lost when they are linked together. I find that hard to believe, but thats why this has 4 seperate transmissions to appease that belief. The pros of simply using a Supershifter will be raised. Yes the motors are being coded to run at the same speed, it is merely electrical differences within the construction of the motors that will create slight variations. Thats my understanding at least. However I am much more mechanically inclined as opposed to electrical/pneumatics, so I could be totally wrong.

You are right. You're team is wrong. There were issues with motor going different speeds forwards and reverse back in the day, when we were using drill motors - which do have a significant bias. However that shouldn't affect your design for three reasons:

1. CIMs do not have a measurable bias
2. The suggestion that the motors would 'fight' is wrong. They will settle into different points on their performance curve, with one doing more work, but they are still working together
3. Motors in the same gearbox are going the SAME direction.