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In a forward dynamic simulation of motion, muscle excitations, joint torques, and/or other applied forces are used to drive the motion of a model. Or in some cases, the model may have its own controller (e.g., that model models reflexes).
The Forward Dynamics Tool takes a set of controls to drive a model's motion by integrating forward in time. An example of such control signals are muscle excitations, which could be collected experimentally or generated via a tool like the Computed Muscle Control (CMC) Tool described above. Note that a forward simulation using such excitation signals without any additional controller will generally not create a stable gait as smaller integration errors can accumulate and experimentally measured EMG is not an exact measure of the underlying muscle activity.
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