Moonwalkers: Evolving Robots for Locomotion in a Moon-like Environment

Robots are arguably essential for space research in the future, but designing and producing robots for unknown environments represents a grand challenge. The field of Evolutionary Robotics offers a solution by applying the principles of natural evolution to robot design. In this paper, we consider a Moon-like environment and investigate the joint evolution of morphologies (bodies) and controllers (brains) when fitness is determined by the ability to locomote. In particular, we are interested in the evolved morphologies and compare the emerging 'life forms' in a Moonlike environment to those evolved under Earth-like conditions. To model the Moon we change two environmental properties of our baseline environment that represents the Earth: gravity is set to a low value and the flat terrain is replaced by the NASA model of the Moon landing site of the Apollo 14. The results show that changing only one of these does not lead to different evolved robot morphologies, but changing both does. Our evolved Moonwalkers are usually bigger, have fewer limbs and a less space filling shape than the robots evolved on Earth.