MTABot: An Efficient Morphable Terrestrial-Aerial Robot With Two Transformable Wheels

Terrestrial-aerial robots, capable of swift aerial navigation and enduring terrestrial operations, possess significant potential for utilization in exploration and rescue missions. However, achieving their capability to negotiate diverse terrains with a high-power-efficient structure remains a formidable challenge. This letter presents a morphable terrestrial-aerial robot, named MTABot, which achieves three modalities through the deployment of two multifunctional appendages. These include: 1) rolling mode, 2) climbing mode, both achieved with transformable two-wheeled configuration, and 3) flying mode, achieved with a bicopter configuration. Moreover, the radius and sector angle of transformable wheel have been optimized to enhance the obstacle-climbing capability; the position of the robot's body center of gravity has been optimized to balance ground gripping capacity and flight dynamic response speed. Finally, the robot's multi-terrain overcoming capability is validated through obstacle-climbing experiments and continuous terrestrial-aerial transformation experiments, and the high power efficiency of robot is affirmed, demonstrating feasibility of the design.