Example: Kinematic data is collected for an $80$ kg man $(180$ cm tall$)$

while walking. Calculate the joint reaction forces and moment at the

ankle. The angular acceleration of the ankle was measured at $21\mathrm{.}69$

ra$($d$)/($s$^(2)),$ and the acceleration of the marker $($@ COG$)$ was $11\mathrm{.}22($m$)/($s$^(2))$

at an angle of $36\backslash$deg from the horizontal. Locations of the marker with

respect to the ankle joint were also measured as seen in the

diagram.