On Attitude Dynamics and Control of Legged Robots Using Tail-Like Systems

In this work we study the attitude dynamics and the control of legged robots using tail-like appendages during the aerial phases of high speed locomotion. A free floating two-body system is used to describe the dynamics of a large body controlling its attitude using a rotating appendage. The equations of motion for a tail and a reaction wheel are given, and the meaning of the generalized coordinates being ignorable or palpable is discussed in detail. A thorough discussion on the holonomy of the system is also included. Analytical expressions are given for a further reduced dynamical model and model-based controllers are then proposed. Finally, we present a series of simulation results, and we derive conclusions that can serve as guidelines when designing such systems.