Chapter 11.5, Problem 11.162P

The angular displacement of the robotic arm is programmed according to the relationship θ = (1/π)(sin πt), where θ and t are expressed in radians and seconds, respectively. Simultaneously, the arm is programmed to extend so that the distance to A follows the relationship r = 4(1 + e^−2t), where r and t are expressed in feet and seconds, respectively. When t = 1.5 s, determine (a) the velocity of point A, (b) the acceleration of point A.

Fig. P11.161 and P11.162