Underactuated multimodal jumping robot for extraterrestrial exploration

Abstract

We present a rolling and jumping underactuated monopedal robot designed to explore multimodal locomotion on low-gravity bodies. It uses only two reaction wheels to control its spatial orientation with two controllers: a balancing controller which can aim the robot's jump direction on the ground, and an aerial reorientation controller which can aim the robot's leg for landing after flight. We demonstrate rolling, targeted jumping and landing, and self-righting using only three actuators total, keeping system size to 0.33m and 1.25kg. Simple switching between locomotion modes enables the system to deal with differing landscapes and environmental conditions.

Figures (14)

• Figure 1: Underactuated robot with one leg and two reaction wheels balancing on a table
• Figure 2: Robot platform from above. The 15-degree cant angle, $\theta$, of the wheels allows for balancing and aerial reorientation while maintaining differential drive features.
• Figure 3: Isometric view of robot platform displayed in CAD
• Figure 4: Rack and pinion design for jumping locomotion
• Figure 5: Robot rolls on the ground in a figure-eight path, blue trajectory overlaid from camera tracking.