Given ri ro that the top bar is moving to the left with

Question

The outer radius of the disk D rolls without slipping at B on the bottom horizontal bar and the inner radius of the disk rolls without slipping at A on the top horizontal bar. Given r_i, r_o, that the top bar is moving to the left with constant speed v_t, and that the bottom bar is moving to the right with speed v_b and acceleration a_b, determine the velocity and acceleration of the center of the disk at C.