Development of a compact jumping lunar rover driven by shape memory alloy actuators

In this study, we developed a compact rover for hopping on low-gravity planets like the moon, exploring the use of Shape Memory Alloy (SMA) actuators to lighten propulsion. Previous designs attached SMA actuators directly to toggle mechanism vertices, consuming energy. To enhance force, we devised a horizontal slider mechanism to drive SMA actuators and the toggle mechanism independently. Validation experiments included correcting initial positions using additional SMA actuators to ensure the proper functioning horizontal slider mechanism. Evaluation experiments showed a 3.6-fold increase in hopping force compared to the previous design. These results establish the feasibility of combining SMA actuators and toggle mechanisms for hopping rovers.