Robotic Actuators for Cryogenic Environments (RACE)

Motiv Space Systems (Motiv) is proposing the Robotic Actuator for Cryogenic Environments (RACE) to address the growing need for precision, high specific-torque robotic arm actuators to operate in low-gravity, extreme temperature environments like that of icy moons or ocean worlds with a premium placed on low energy usage. RACE is a novel approach to cryogenic actuators that is easily scalable and modular by design. RACE leverages Motiv’s work developing planetary gearboxes with the Distributed Extreme Environments Drive System (DEEDS) program and will implement a single-pass cycloidal reducer as the output stage. RACE is a heater-free, BMG-based actuator with a small cycloidal output stage driven by a brushless DC gearmotor. Construction of the motor and gearbox is based on that developed for the Cold Operable Lunar Deployable Arm (COLDArm). Both COLDArm and DEEDS feature BMG components to enable operation at -180C, and both programs introduced BMG elements as “drop-in” substitutions for mechanism components typically made of standard materials comprising Motiv’s designs. Motiv is thus in a unique and exceptional position to develop and compare the performance of established flight heritage designs to more leading-edge approaches offered by incorporating the BMG components. Additionally, Motiv’s understanding of robotic systems from development and performance standpoints deeply informs the trade-space when introducing new advances such as the proposed innovation.
Benefits: The Planetary Science Decadal continues to place emphasis on the discovery to the origins of life. New mission sets have been evaluated with desires to investigate some of the most remote and harsh environments our solar system has to offer. Some of these unique destinations include Enceladus, Europa, Ganymede, comets and asteroids. Common to many of these destinations are extremely cold operating environments, in particular the ocean worlds and icy moons where temperatures regularly dip below -150C. The greatest objective is to maximize science content. A means to maximize science payload is to minimize the burden of survival heater power. RACE offers a solution to operate robotics, instrument mechanisms, or sampling systems within the local environment without external heating augmentation. This is a significant benefit in power and mass savings which are the most precious resources to be conserved in mission development. Motiv envisions a variety of space robotic applications that fit within the commercial landscape. In particular, the growth and focus on Lunar applications, especially within the permanently shadowed regions are excellent examples of near-term need. Motiv expects as the drive to sustainable operations on the Moon grows, demand for cryogenic capable systems, which can be affordably produced and withstand the extreme environments, to become critical to the transition from demo to long term mission status. Beyond space applications, Motiv has been investigating terrestrial applications for cryogenic mechanism needs within the larger scientific community.