Hey everyone, i am trying to design a small and lightweight cvt (continiously variable transmission) for an electric car that can either be on or off, no variable speeds from the motor. I am having trouble representing the math of the transmission. I have to have the car complete a race of 312 inches, the motor has a top rpm of 4040rpm, and at that rpm torque approaches 0. the graph of the torque vs rpm is piecewise in 2 parts with the following equations when rpm<1248 then torque=-0.0019*rpm=23.3 and also when rpm>1248 then torque=-0.0075*rpm=30.3(adsbygoogle = window.adsbygoogle || []).push({});

anyway, my problem is that i dont know how to represent a smooth change between the infinite gear ratios and relate that to how much time it will take to cross the finish line (312 inches later). obviously i am starting at a velocity of 0, and an rpm of 0. this should give me a torque just as the motor starts to move of 23.3 ounce-inches. i know i want to minimize time, and maximize velocity. i think i have to use an integral to represent the cvt, but im really turning around in circles here. oh and by the way, the diameter of the drive wheels is 3 inches. please can anyone help me out here?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# CVT transmission for an electric motor

**Physics Forums | Science Articles, Homework Help, Discussion**