Fig. 10. Comparison of the joint kinematics of model 3 (red lines), model 4 (blue
lines) and experimental frogs (black line represents data from one frog). The
forward dynamics of models 3 and 4 were driven with the joint torque pattern
estimated from the kinematics of experimental frogs. The hindlimb joint angles
of both models closely corresponded to the experimental data for the first
70ms of each simulation run. After 60-70ms, the metatarsal joint (Meta) of
experimental frogs begins to extend (lower right panel). Model 3 did not
capture this reversal of tarsometatarsal joint motion because the
metatarsal—phalangeal segment was fixed to the ground. Model 4, which
allowed passive rotation of the metatarsal segment above the ground (i.e. no
active torques were applied about the tarsometatarsal joint), did capture this
kinematic effect. ab—add, abduction—adduction; Ext, external.
