How can I change the position of revolute joint?

I have three revolute joints. and I am appling different input to them. ı applied the motion input to one and ı applied zero tork to other one and ı applied the 50 tork to other one also. but all of joint stayed the same position. they never motioned in simulaion. ı did not understand. how ı motion different type these joints. these joints are between motor and rotational piece. and I want to simulate platform by adjusting different angle position of these joints.