Mechanical Design and Modelling of a Robotic Planetary Drilling System

Abstract

Deep space drilling is necessary for appropriate chemical and biological sampling for subsurface exploration. The Robotic Planetary Drilling System (RPDS), which is currently being developed by our team, is designed to be a compact self-propelled, steerable electromechanical drilling system that can penetrate into large depths in planetary bodies. In this paper we present the detailed innovative mechanical design of the RPDS. Its main components are: a) the drill bit/cuttings bucket, b) the rotary propulsion unit including novel three 3-degree of freedom (DOF) propulsion actuators, c) the power/control module, d) the non-rotating steering unit including three 1-DOF steering actuators and e) the communication module. Three 3-DOF propulsion actuators uniformly distributed around the rotary propulsion unit impart rotating, linear motion to the drilling bit, while another three 1-DOF steering actuators provide the steering force for automatic directional control. The RPDS is propelled in the manner of a turning screw, which offers simpler kinematics structure, higher efficiency and thus, potential for miniaturization and deep drilling. The mathematical modeling and analysis of the RPDS that were conducted to evaluate its performance are also being presented in this paper.