  Flippers are essential components of tracked robot locomotion systems for
unstructured terrain, especially within a rescue scenario. Achieving full and
semi-autonomy for such rescue robots is the goal of many research efforts. In
this work, we propose an algorithm to plan the morphologies of a small rescue
robot with four flippers over 3D ground without any extra sensor, such as
pressure sensor. To achieve the goal, we simplify the rescue robot as a
skeleton on inflated terrain. Its morphology can be represented by
configurations of several parameters. Then we plan the mobile movement on 3D
terrain with four individually manipulated flippers. We perform real robot
experiments on three different obstacles. The results show that we move the
flippers very effectively and are thus able to tackle those terrains very well.
