Preliminary Thermal Design of an Australian Lunar Rover for Polar Exploration

This paper describes the preliminary thermal design of a 20 kg class Lunar rover for the Australian Space Agency’s Trailblazer Program, the first undertaking of its kind in Australia. Despite being a technology demonstration, the national significance of the mission places demanding challenges on the thermal design. The rover is designed as a payload on a Commercial Lunar Payload Service (CLPS) mission to the South Pole (>80° S) of the Moon, but the lander will only be selected late in the project. Thus, the design must allow for the wide range of sometimes opposing thermal requirements that arise from the different potential accommodation options and Lunar transfer scenarios. The rover’s thermal design is driven largely by simultaneous consideration of the battery’s narrow allowable temperature range, the wide range of temperatures experienced by externally-mounted actuators, radiator area and degradation due to dust and the rover’s orientation relative to the solar vector. Finally, TCS resource requirements must be balanced with constrained system power and energy budgets. All these considerations demanded a high degree of thermal model fidelity early in the project, with a need to perform detailed steady-state and transient analyses of mission activities, despite significant open requirements.