Hi Guys, so I will need to hook up the motors to some sort of controller. I have been looking at Dimension engineering web site and they sell controllers that make it easy to hook up a RC radio and receiver to wheelchair motors. I am wondering if I should order one of these or should I simply use an Arduino board with relays? I guess allot depends on my motors, here is a pic of the plug on my motors. I want to control the robot by RC radio but I also want it to eventually be able to mow the lawn on its own so I need to plan ahead.
Maybe you should contact Dimension Engineering and ask them?
I would -not- use relay control with these motors, as usually they use some form of PWM control for speed (when used on a wheelchair), and some of those motors can move a chair quite fast; waaay faster than a slow walking speed (like you would use when mowing/blowing snow). Heck, the other day, I saw a guy pop a wheelie in the crosswalk as he was taking off (I thought he was going to fall over backwards, but his wheelie-bar wheels on the back saved the day!)...
Ultimately, you are definitely going to want a pre-built controller for these motors; I haven't looked at all of your pics, but I am guessing they are 24 VDC motors, and pull quite a bit of amps (from a dead stop or stalled). Try to get in contact with Invacare, and see what (if anything) they can tell you.
Also, if you look a bit online, you will find companies that repair these chairs and/or sell parts - try contacting them. Finally, contact Dimension Engineering and/or others that sell large controllers for these kinds of motors. You need to first find out how much current these motors pull in running vs. stalled conditions; if you are unable to figure that out, get the biggest controller available for a powerchair (or try to hack the one that came with the chair if it is still attached).