Human balance during quiet stance (a.k.a. standing still) is not actually still at all but involves...

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Human balance during quiet stance (a.k.a. standing "still") is not actually "still" at all but involves dynamic rotation primarily about the ankle. We will model this standing motion as illustrated in the figure to the right. The entire mass of the body is concentrated at the center-of-mass (COM) and rotates about the ankle at an acceleration of a that varies over time, the feet are fixed to the floor, and the contribution from the ankle muscles can be modelled as an ideal torque actuator. gravity, g mass = M d e a. Draw the free body diagram and kinetic diagram Ankle joint 65 kg? b. What is the inertia of the body about the ankle if d = 1m and the mass = c. What is the torque being produced at the ankle at an instant in which the body is falling forwards at an acceleration of 40/s as is passes through a position of 0 = 85? d. As the body returns upright, what is the torque being produced at the ankle at the instant when 0 = 85 and a is 35/s? e. Discuss how your answers in parts (c) and (d) compare to the torque required to maintain a static position of = 85. For example, does the magnitude of the ankle torque make sense for the motion of the body in each case? Human balance during quiet stance (a.k.a. standing "still") is not actually "still" at all but involves dynamic rotation primarily about the ankle. We will model this standing motion as illustrated in the figure to the right. The entire mass of the body is concentrated at the center-of-mass (COM) and rotates about the ankle at an acceleration of a that varies over time, the feet are fixed to the floor, and the contribution from the ankle muscles can be modelled as an ideal torque actuator. gravity, g mass = M d e a. Draw the free body diagram and kinetic diagram Ankle joint 65 kg? b. What is the inertia of the body about the ankle if d = 1m and the mass = c. What is the torque being produced at the ankle at an instant in which the body is falling forwards at an acceleration of 40/s as is passes through a position of 0 = 85? d. As the body returns upright, what is the torque being produced at the ankle at the instant when 0 = 85 and a is 35/s? e. Discuss how your answers in parts (c) and (d) compare to the torque required to maintain a static position of = 85. For example, does the magnitude of the ankle torque make sense for the motion of the body in each case?