Hi i'm engineering student and am very new to circuits, as in I haven't taken any circuits courses yet. I'm familiar with the very basics of circuits and programming and would like to see if any one could give me some ideas to how to approach this. My goal is to emulate a DC motor by using whatever means to create a circuit that has a variable resistance that can be micro-controlled with the raspberry pi. The idea is that if I can change the resistance through the pi I can emulate the current draw of the DC motor. For example when it starts up it has a huge current spike of then levels off, and if it has variable loads I can account for that with a current oscillation all by programming it on the pi. I'm thinking that I should use PWM and transistors to accomplish some sort of variable resistance but am not really sure if this would be the best or simplest approach. I would very much appreciate any ones input on this project that could help me get going.