Meriam, Kraige & Bolton — Plane Kinetics of Rigid Bodies: Problem 6_190

6/190 Reconsider the basic mechanism of Prob. 6/188, only now the mass of the crank $OA$ is $1.2\text{ kg}$ and that of the uniform output arm $BC$ is $1.8\text{ kg}$. For simplicity, treat the crank $OA$ as uniform. Determine and plot the torque $M$ which must be applied to the crank at $O$ in order to keep the speed of the crank steady at $60\text{ rev/min}$ over the range $0 \le \theta \le 2\pi$. What is the largest magnitude $M$ which occurs during this motion, and at what angle $\theta$ does it occur? Additionally, plot the magnitude of the force on each pin over this range and state the maximum magnitude of each pin force along with the corresponding crank angle $\theta$ at which it occurs. Reference data from Problems 6/188 and 6/87: - Link lengths: $OA = 80\text{ mm}$, $AB = 240\text{ mm}$, $BC = 200\text{ mm}$. - Fixed points: $O(0,0)$, $C(190\text{ mm}, 70\text{ mm})$. - Coupler mass: $m_{AB} = 7\text{ kg}$. - Input motion: $\omega_{OA} = 60\text{ rev/min} = 2\pi\text{ rad/s}$ constant counterclockwise.