Lizard: A Novel Origami Continuum Mobile Robot for Complex and Unstructured Environments

Abstract

Lizard is a soft mobile robot equipped with six three-spoked whegs to negotiate uneven terrain and a flexible spine to enhance maneuverability and obstacle-climbing performance. The flexible spine consists of an origami bellows structure fashioned from laser-cut plastic sheets and actuated by three cables attached to Direct Current (DC) motors at the base of the module. Lizard is highly maneuverable and adept at traversing various types of rough terrain. It has a turning radius as low as 18 cm, which allows Lizard to navigate difficult passageways and cluttered environments. Lizard can also travel at 39.20 cm/s on flat carpeted terrain and climb obstacles up to 132 mm tall or 2.40 times higher than the length of the wheg. In addition, we discuss CHOMP+, an optimal motion planning algorithm based on constrained Covariant Hamiltonian Optimization for Motion Planning (CHOMP), for mobile robots with a limited turning radius. We experimentally demonstrate CHOMP+ generating a curvature-bounded path for Lizard through a populated environment in 213 ms.