Frictional Locomotion of a Radially Symmetric Tripedal Robot

Abstract This study seeks to provide physical insight into the friction-driven crawling locomotion of systems with radially symmetric bodies. Laboratory experiments a tripedal robot show that both translation and rotation can be achieved just three independently actuated rigid limbs, i.e., 3 degrees-of-freedom. These observations are rationalized using simple mathematical model, which assumes friction at each limb is linearly proportional normal force contact point, opposes direction motion. dynamic model reproduces experimental across an extensive parametric sweep involving sinusoidal limbs varying amplitudes phase shifts. Model predictions highlight role played by time-varying forces points. confirmed embedded transducers in limbs. We present further simplified analysis explaining geometric nonlinearity induced dynamics from radial symmetry this essential generation pure translation. also amplified cyclic length variation. results framework for movers.