Practically speaking, I don't think you can calculate it...
You may want to re-think having a motor per wheel with tank treads; if the motors aren't perfectly synced and moving at the -exact- same speed, you will throw the tread (and/or cause problems for the motors/gear-train). Instead, use only a single motor per tread (just like tanks and bulldozers do).
I am a programmer and am just getting into robotics/electronics. I would like to build an Arduino-based robot that I can control from an app on my Android phone. I am planning on the robot having 4 motors (actuators?) controlling 4 wheels (1 tank tread/belt on each side; 2 wheels per tread/belt).I am trying to determine how "heavy duty" my motors need to be, and not sure where to start in my calculations. Here's some constraints/preferences:Speed is not critical, maybe top-speed of ~2mphIt's tough telling how heavy the robot will be at the outset, but probably no more than 3 - 5lbsLooking for lowest power consumption possible (given the above constraints) to provide max battery lifeI'd prefer < $20/motorAfter a cursory review of several websites, it looks like motors are measured by the following properties:VoltageRPMTorqueReductionSo we have a ~4lb robot distributing that loads over 4 motor-actuators with a desired top-speed ~2mph. I'd like the motors to meet those capabilities as well as run on as little power as possible, all within the $10 - $15 per motor price range.I'm not asking for other members to make suggestions on particular models ("give a man a fish"), what I'm asking is what calculations most robot hobbyists would use in this scenario to take all these factors into account and make an educated guess on what type of motor I need ("teach a man to fish"). So, where do I start?!? Thanks in advance.
It will take very little power to drive the robot on a flat surface, so you need to concern yourself with the maximum thrust you will get. This will be either how much mass you can PUSH with your robot or how steep an INCLINE you can climb.