Find the driving torque and the reaction forces at the joints for the crossed linkage in the posture shown. For the constant angular velocity

ω2 = 10 rad/s ccw, the known kinematics are

ω3 = 1.43 rad/s cw, ω4 = 11.43 rad/s cw, α3 =

α4 = 84.8 rad/s2 ccw, and AG3 = 25.92ˆi +

24.58ˆj ft/s2. The external force at point C is FC = −30ˆj lb. The weights and mass moments of inertia of the links are w3 = 4 lb, IG2 = IG4 =

0.063 in · lb ·s2, and IG3 = 0.497 in · lb ·s2.

Figure P12.20 RAO2 = 6 in, RO4O2 = 18 in, RBA = 18 in, RBO4 = 6 in, RCA = 24 in, and RG3A = 12 in.