Modular leg robot varies morphology and control for diverse locomotion studies

Bio-inspired legged robots serve as useful testbeds for testing biomechanical hypotheses. Custom-designed robots anchored in detailed morphology demonstrate how extinct animals may have moved, while commercially available robots with more abstract morphologies provide insight into template models of control. However, few robotic systems allow easy customization of both hardware and software to understand how morphology and control interact to affect locomotion. To bridge this gap, we present a Modular Leg robot as a low-cost platform for locomotion experiments. Each limb can consist of either two or three telescoping links that determine the relative proportions of limb elements. Limbs can be reflected to match either a knee or an elbow configuration and a modular torso design can house either two or four limbs in a primarily sagittal mammalian posture. The leg can have varying joint ranges of motion and virtual leg stiffnesses. Thus, the Modular Leg robot can match the relative physical properties of many extant animals, extinct animals, and existing commercial robots. Limbs are actuated by backdrivable quasi-direct drive actuators that are compatible with template-based control strategies employed by successful research and commercial legged robots and alternative strategies that incorporate morphological information. The 3D printed design enables rapid production, repair, and customization. We also demonstrate the use of this platform as a teaching tool with an undergraduate mechanical engineering design course. We hope that this Modular Leg robot can broaden the use of robotic platforms to test biomechanical hypotheses and inform the future design of robotic limbs.

@inproceedings{urs2023modular,
  title={Modular leg robot varies morphology and control for diverse locomotion studies},
  author={Urs, K and {Enninful Adu}, C and Moore, TY},
  booktitle={INTEGRATIVE AND COMPARATIVE BIOLOGY},
  volume={62},
  pages={S314--S315},
  year={2023},
  organization={OXFORD UNIV PRESS INC JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA}
}