@Cameron https://www.robotshop.com/blog/en/files/sunforcebal.jpg may be wrong: in a force balance, Ma = T/R-Mg*sin(theta). Friction is up the incline, in the direction of the acceleration (which is contrary to a ball rolling down the incline).
Great article. I am in the process of making a unit to traverse around the farm and change attachments to do various tasks. This article has been a huge help. I am a sparky by trade and therefore doing a hybrid diesel/electric unit using 3 phase geared motors at the drive wheels and controlling these using VSD units. This reduces the size of wire and enables me to use off the shelf control units complete with inbuilt reverse, braking etc. Your info has been a great help in assisting me with calculations.
@Cameron It’s really up to you - it’s part of the equation so it needs to be considered. Looking into the moment of inertia may be a bit much (but certainly not out of the question if you want to be precise). Just think of the distance you want it to cover in order to reach a certain speed (from a dead stop).
Yeah that’s what I have done. Looked into inertia calculations but can get a bit nightmare trying to find CG of individual components and such like. Glad you’re still around though, noticed this was originally posted in 2012!
@crawler The efficiency is the overall efficiency of the system, most notably the batteries -> motor controller -> DC motors -> Gearbox. If you have data as to the efficiency of each section, multiply them all to get a total efficiency. If not, you will need to estimate the value. For example spur gears are around 65% efficient.
