Quote:
Originally Posted by Donut
I understand the theoretical max speed won't increase with additional CIMs since they all have the same free speed, but won't the effective speed you can reach change because of the additional torque available at the same point on the motor torque/speed curve? If the kitbot is rated at 75% of free speed due to friction losses on one CIM per side, then I would think the additional CIM per side would add enough extra power to run at a higher percentage of free speed before friction becomes the limiting factor again. Is there a significant amount of friction added from the extra gear for the second CIM?
|
It's definitely a second order effect. Essentially, by doubling the torque available at the highest speeds, you are going to be able to get closer to free speed. That is, the "speed loss constant" in JVN's calculator will nudge a bit closer to 100%. (or more likely, move farther away from 100% on the 2 CIM side, because I'm pretty certain that 4-6 CIM geartrains are far more typical of the ones used to determine the 81% value).