The robotic device consists of the stationary pedestal OA, arm AB pivoted at A, and arm BC pivoted at B. The rotation axes are normal to the plane of the figure. Estimate 

(a) The moment MA applied to arm AB required to rotate it about joint A at 4 rad/s² counterclockwise from the position shown with joint B locked 

(b) The moment M_B applied to arm BC required to rotate it about joint B at the same rate with joint A locked. The mass of arm AB is 25 kg and that of BC is 4 kg, with the stationary portion of joint A excluded entirely and the mass of joint B divided equally between the two arms. Assume that the centers of mass G₁ and G₂ are in the geometric centers of the arms and model the arms as slender rods.

Transcribed Image Text:

B G2 mm G1 06 C 45° A 350 mm 00