It occurs to me that the FAQ points to lots of information on how to design a drive train (gear ratios, etc.) - but nothing on the power train.
So… I wonder if anybody has a good writeup or video that works through the entire math from: Basic Operating Characteristics (speed range, load, inclines, operating range, etc.) -> Specifying/picking a motor (KV, power, etc.) -> Specing & Configuring an ESC/VESC -> Specing a battery pack (S, P, C, Capacity)
Bonus points for how this all interacts with drag, gearing, and torque/power curves for motors. Even more bonus points for electronic braking/recharging.
Specific case in point: I’m working on an “electric walker” (i.e., adding motors to my dad’s walker). Ideally, I’m looking at using dual hub motors, with tank steering (to stay away from the maintenance headaches of a belt drive system, and maybe look at very small wheels before a gear/belt system). Looking to achieve avg. speed of 3mph, top speed of 4mph, a range of maybe 4 miles (1 hour). Assume a 180 pound rider, smooth level ground.
So I’m trying to work through everything from peak/average power required from the motor(s) to motor ratings to VESC rating/specs to battery specs.
And, as a separate exercise, holding the load constant, examine the implications of different motor specs & gearing on the power system specs.
So… anybody have a pointer to a good tutorial, video, or book that works through the step-by-step design process from an engineering point of view? Or maybe somebody who’d be willing to spend some time working with me to put together such a writeup? (I’m an engineer by training, but more electronics/computers/network stuff - mechanical and motor stuff is new ground, and I’m not familiar with either the math, or the practicalities of available components.)
Thanks!