The leg of a bicyclist can be modeled as a fourbar ZABY as shown. For this...

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The leg of a bicyclist can be modeled as a fourbar ZABY as shown. For this configuration, the frame (ZY) makes a 250 degrees angle with the horizontal, the thigh (ZA) is at 210 degrees, the leg (AB) is -105.5 degrees, and foot+pedal (YB) is 158.43 degrees with respect to the horizontal. The corresponding link lengths are ZA=0.45m, AB=0.5m, BY=0.25m, and ZY=0.85m. The mass of thigh, leg, and foot+pedal are 10, 5, and 2 kg respectively. The moment of inertias of thigh, leg, and foot+pedal are 0.36, 0.12, and 0.05 kgm² respectively. Furthermore, after performing a full motion analysis, we know that the angular velocities of the thigh, leg, and foot+pedal are 1.04, -0.74, and 1.32 rad/s, and the angular accelerations in the same order are 0, 0.329, and -2.71 rad/s² Assuming the rider is riding on sand (high rolling friction), they will experience a torque of -35 N at the pedal due to friction. You are also given that the power expended by the inertial forces (not torques) at this configuration is -0.5993 Watts. Find the torque in Nm exerted by the thigh (at the hip socket) to maintain this speed. Do not ignore external forces due to gravity on each limb and pedal and assume 100 percent efficiency. Write your answer up to 2 decimal places without units in the response box. The leg of a bicyclist can be modeled as a fourbar ZABY as shown. For this configuration, the frame (ZY) makes a 250 degrees angle with the horizontal, the thigh (ZA) is at 210 degrees, the leg (AB) is -105.5 degrees, and foot+pedal (YB) is 158.43 degrees with respect to the horizontal. The corresponding link lengths are ZA=0.45m, AB=0.5m, BY=0.25m, and ZY=0.85m. The mass of thigh, leg, and foot+pedal are 10, 5, and 2 kg respectively. The moment of inertias of thigh, leg, and foot+pedal are 0.36, 0.12, and 0.05 kgm² respectively. Furthermore, after performing a full motion analysis, we know that the angular velocities of the thigh, leg, and foot+pedal are 1.04, -0.74, and 1.32 rad/s, and the angular accelerations in the same order are 0, 0.329, and -2.71 rad/s² Assuming the rider is riding on sand (high rolling friction), they will experience a torque of -35 N at the pedal due to friction. You are also given that the power expended by the inertial forces (not torques) at this configuration is -0.5993 Watts. Find the torque in Nm exerted by the thigh (at the hip socket) to maintain this speed. Do not ignore external forces due to gravity on each limb and pedal and assume 100 percent efficiency. Write your answer up to 2 decimal places without units in the response box.

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To find the torque exerted by the thigh at the hip socket we can use the principle of power balance ... View the full answer