The results show that the performance of RRT-MP is determined
by the capabilities of the utilized motion primitives. Therefore,
RRT-MP-a fails to overcome the steps, as it is equipped only with
primitives suitable for a planar environment without obstacles
that require the body to be raised. By contrast, RRT-MP-r is able
to reach the goal position and to overcome the steps. It should
be noted, that only one primitive in RRT-MP-r can raise the head
and therefore climb the step, while the other primitives can only
move the robot on the ground. This shows the importance of using
primitives suitable for a given situation.