Hey Malcolm,

Ok, I understand what your concern is now.

I agree, this is a potential failure mode, and it's a little difficult to calculate and predict the effects of impacts in system like this that is rubber mounted. It can be done, but I think in our case prototype testing is more time and resource efficient.

Our current thinking is that the rubber mounts are going to go a long way towards absorbing and mitigating the kinds of impacts that you describe, and our design intent is to have enough strength and robustness in the Drive so that mounting system will fail before the Drive does.

We want to start our testing and evaluation with a 5mm shaft because this is the lightest setup, but if shaft bending does prove to be an issue, we have enough design freedom to increase the shaft diameter to 6mm or even 8mm if we have to, but I want to end up with the lightest setup that will do the job.

Brenner ...