This paper presents a method for computing the track forces and track
speeds of planar tracked vehicles, required to follow a given path at
specified speeds on horizontal and inclined planes. It is shown that t
he motions of a planar tracked vehicle are constrained by a velocity d
ependent nonholonomic constraint, derived from the force equation perp
endicular to the tracks. This reduces the trajectory planning problem
to determining the slip angle between the vehicle and the path tangent
that satisfies the nonholonomic constraint along the entire path. Onc
e the slip angle has been determined the track forces are computed fro
m the remaining equations of motion. Computing the slip angle is shown
to be an initial boundary-value problem, formulated as a parameter op
timization. This computational scheme is demonstrated numerically for
a planar vehicle moving along circular paths on horizontal and incline
d planes.