Bio-inspired Legged Robot for Space Exploration

Harsh terrain such as inclined craters, fine regolith and vast canyons inhibits interplanetary exploration by wheeled rovers. Such landscapes could be effectively traversed through the application of unique movement patterns used by animals. This paper presents a hopping robot that imitates the bipedal hopping and pentapedal bounding gaits of a kangaroo for the purpose of interplanetary exploration. The gravitational accelerations of other planetary bodies require the adaptation of traditional locomotive patterns. The hopping motion of a kangaroo is ideal for low gravity conditions as it requires less energy for take-off, offers extended flight times and allows for manoeuvring over large obstacles. In addition to the hopping gait, kangaroos incorporate a pentapedal bound for slow and precise movement during grazing. The design approach focused on rapid prototyping, due to the novel nature of the system, allowing for an iterative testing approach. The components were 3D printed to reduce the manufacturing costs and weight of the design. A lightweight design allows for increased jump height, low power motors and reduced impact stresses. A scaled functional prototype was created to accelerate the development of the system through rapid testing of gait patterns. A variable gravity testing rig was constructed and utilised to simulate a range of gravitational accelerations. An optical tracking system was used to provide precise data on the movement of limbs for analysis. This paper demonstrates the feasibility of bipedal hopping robots for the exploration of lower gravity planets. The bio-inspired legged robots provide a strong foundation for the future development and refinement of these gait patterns.