NASA's Ground Test Unit (GTU) Lunar Terrain Vehicle (LTV) Conceptual Hand Controllers Studies

Over that past year, the National Aeronautics and Space Administration (NASA) has been preparing and developing a set of standardized testing protocols for the commercial LTV vendor selection. Two studies have been conducted on two possible hand controller concepts specifically designed for the operation of NASA’s Ground Test Unit (GTU) Lunar Terrain Vehicle (LTV) that can be applied to the heretofore unknown designs developed by future LTV vendors. The objective for the two studies were to determine which hand controller enable acceptable operation of the LTV in a simulated lunar traverse. In the first evaluation a total of nine subjects in shirtsleeves with ungloved hands performed two simulated lunar driving courses in an engineering simulator with each hand controller. Controller concept one was the T-handle fashioned after the Apollo Lunar Roving Vehicle’s (LRV) T-Handle controller. The rational for using this design is it’s a proven design while in a pressurized suit. However, the LTV does have a driving mode the LRV did not consider. The mode of crabbing or strafing the vehicle at different angles; thus, the idea of a dual T-Handle controllers to accommodate this function without using a switch or display was introduced. The second concept controller is a new innovative controller call the Tri-Rotor [NASA patent review MSC-27385-1]. Inspired by Formula One race steering, the Tri-Rotor was designed to take advantage of the restricted movement and dexterity of a pressurized space suit. During testing, all subjects were able to successfully navigate through two test courses of varying lengths and complexity. Results indicated the dual Thandle had minimal recommendations for improvement while the Tri-Rotor had more extensive ones. It must be noted, the Tri-Rotor is a first-generation prototype and has some known mechanical concerns; thus, recommendations from this study will be incorporated into the second generation.