From what I understand, human arms can be thought of as third class levers, so that the distance from your elbow to the place where the muscle attaches is effectively the distance to the fulcrum, so that arms produce proportionally less strength on the end, and proportionally greater distance when lifting a load. So this is somewhat of an anatomy question (although I suppose if it was to be used for an exoskeleton, it could be robotics) but can leg muscles and the muscles that attach to the ends of arms and legs be roughly modeled in such a way? What muscles/muscle groups don't classify that way?
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