Musculotendon dynamics

For the actuator shown in Fig. 6.21, musculotendon dynamics is described by a single, nonlinear, differential equation that relates musculotendon force (F "), musculotendon length (P"). musculotendon shortening velocity (v "), and muscle activation (n") to the time rale of change in musculotendon force ... 

FIGURE 6.22 Comparison of the forward- and inverse-dynamics methods for determining muscle forces during movement. Top Body motions are the inputs and muscle forces are the outputs in inverse dynamics. Thus, measurements of body motions are used to calculate the net muscle torques exerted about the joints, from which muscle forces are determined using static optimization. Bottom Muscle excitations are the inputs and body motions are the outputs in forward dynamics. Muscle force (F ) is an intermediate product (i.e., output of the model for musculotendon dynamics). 

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