A 60kg, 185cm male is holding a tool, mass of 20 kg, in his right hand. He is holding the tool in a position where his upper arm is 55° below horizontal and his lower arm 30° above horizontal. The hand and tool are held at the same angle as the lower arm.
a. Draw an appropriate FBD or FBDs incorporating all relevant joints, moments, and forces for this problem. Determine segment lengths, COM of segments, and force magnitudes.
b. Calculate the external force and moment at the elbow.
c. Calculate the external force and moment at the shoulder.
d. Given the following values, what percentage of the population could perform a flexion task in this position? Flexion: mean (m) = 30Nm and (s) = 10Nm.