Jumping Mechanism Using Shape Memory Alloy Actuators for a Lunar Rover

A jumping lunar rover is able to move around regardless of ground conditions and jump high under the low gravity like the moon. The weight of the rover influence the jump distance. Therefore, the jumping lunar rover needs to reduce its weight. In this research, we focused on a shape memory alloy (SMA) actuator as the driving source. A SMA actuator has some advantages such as light and high output power per unit volume. We fabricated a toggle mechanism using SMA actuators for a jumping lunar rover. The proposed toggle mechanism consists of two links and a shaft. In this mechanism, SMA actuator is used for the operation of this link. The manufactured mechanism measures 215 mm around the outside, 128 mm in height and weighs about 600 gram. We performed jumping experiments in the vertical direction and evaluated the jumping performance. As a result, we confirmed a jump of 0.17 m in the vertical direction.