Looking at the parameters of the Nema 17 Stepper Motor, I can't see the max RPM characteristic. I'm looking to offer three speed settings for a continuous camera track slide over 1.5m and need to work out what those speeds would be. Not being a mathematician I wouldn't know how to start about this issue but having access to the RPM would allow me to take into consideration the pitch of the threaded drive shaft on which the camera sled, with a payload variance of between just 750gr and 3kg is sitting. This motor may be overkill though as i want to have the unit as portable as possible with the power source being incorporated into the control panel and to be able to be simply recharged in situ. Given my tack will be the max 1.5m long, and the sled payload differing between .75kg and max 3kg sitting on a 5mm threaded steel drive shaft what motor meeting the criteria above would be suitable and the big question being what kind of rechargeable power solution should I look at bearing in mind there is a microcontroller within the system that doesn't like north of 5v solutions. Cheers, Mark. PS If I'm overlooking the obvious just kick me.