Advancements in bio-inspired robots have demonstrated extraordinary capacity to tackle locomotion problems. In dealing with complex terrains, the application of multimodal principles has shown versatility and flexibility in locomotion as the robot can better adapt to different terrestrial conditions. This project aims to design and fabricate exoskeleton mechanisms that allow a robot to mimic the curl and uncurl motions, referred to as conglobation, of pill bugs. Pill bugs use this trait to great effect in adjusting to their dynamic environments, and robots could benefit from such adaptability. The proposed mechanisms will allow a robot to switch between crawling and rolling modes for adaptive locomotion, easier transportation, and better protection of the robot body.

In this project, we primarily focus on designing and fabricating an exterior shell inspired by pill bugs’ exoskeleton. Specifically, we want to design a hierarchical shell structure that can change between flat and spherical configurations. The major problems are listed in a tree diagram.

In addition, our design should satisfy the following requirements:
●       As we use an existing robot (about 20cm x10cm x10cm), our exoskeleton design should be compatiblewith our base robot’s dimensions.
●       The exoskeleton should be able to expand to a spherical shape in two degrees of freedom.
●       The resulting spherical robot should be able to roll if actuation is added.