Design and Optimization of Foot Locus Trajectory of Theo Jansen Mechanism

The single degree of freedom legged robots are functional in terms of its simplicity and performance on both even and uneven terrains. The performance stability of these legged robots is determined by the trajectory of their foot locus. In the present work, Theo Jansen mechanism is used as locomotive drive mechanism for legged robot. The mechanism is designed and optimized using the Synthesis and Analysis of Mechanism (SAM) software during the conceptual design phase. The embodiment design was completed using CATIA. Simplex and evolutionary algorithms were utilized for optimization of foot locus to improve its step height and stride length. The influence of the link length and the input crank angle on the foot locus trajectory has been illustrated and compared for three different trials. The obtained results are compared with standard foot locus. Further, the results derived in this work can be utilized in selecting the link length for Theo Jansen mechanisms for various applications.