Surface vehicle vertical trajectory planning

An active suspension is disclosed for us with a surface vehicle for operating along a path and which includes a payload and payload compartment. The active suspension has a controllable suspension element for modifying the displacement between the payload and the path, responsive to vertical disturbances in the path. A subsystem for issuing commands to said controllable suspension element to cause said controllable suspension element to exert a force responsive to a vertical disturbance in said path, to cause the displacement between said payload compartment and said path to change prior to said surface engaging device encountering said vertical disturbance.