Originally Posted by
howardcano
That would certainly take care of misalignment, but I fear that the time data would be severely skewed due to twisting of the cable. 1us of time doesn't equate to much angle at these speeds; it's about 0.05 degrees at 8000 RPM. I'm guessing that the cable would probably twist at least an order of magnitude more than that.
True. On top of that, the amount of twist as the motor ramps up would also probably not be consistent between different motors. A u-joint or CV joint could allow some slight misalignment and if kept to a minimum, maybe it would have a negligible affect on the results? Not sure how much the speed up/slow down effect would be if kept mostly straight.
Originally Posted by
howardcano
I was thinking something similar to a third-bearing clutch support on a kart, with a solid connection between motor and flywheel, but with restriction on radial movement and wobble.
Not familiar with that, but after looking at some pics, I think I see what way you are thinking. Using the bracket and bearing for a fairly frictionless middle support and alignment. The coupler at that point could possibly be an aluminum tube with the center drilled the size of the shaft(s) and set screw to tighten. The fun part would be getting the motor mount plate centered.
Originally Posted by
howardcano
But first we will need to see the if the data from many runs with the gear reduction shows undue scatter, or if all of my worries are unfounded!
Keeping my fingers crossed. As before, you have me intrigued again with one of your projects. I really need to work on my electronics knowledge.