|The 2011 Desert RATS field test simulated human scientific exploration of a Near Earth Asteroid. Test conditions involved 3 or 4 human crewmembers operating from prototype Space Exploration Vehicles (SEVs) and/or the Deep Space Habitat (DSH), command station, assumed to be in orbit around the target. Extra Vehicular Activities (EVAs) could begin from the DSH or the SEV. A 50-second one-way communication delay between the crew and Mission Control Center (MCC) and Science Support Room (SB) was introduced in this test. Internal Vehicular (IV) crewmembers were located inside the SEV, DSH or both, and experienced no time delay with EVA crew. The time delay made it impractical to carry on voice conversations with MCC and SB, and the crew adapted to depend on themselves for tactical science decisions. This situation placed increased responsibility on the crew geologists to perform the role of field science “PI”. As a result, the position assignment of the crew geologists within the test produced intriguing results.
In order to simulate microgravity, we tested two EVA modes of operation. One involved a theoretical self-contained propulsive backpack dubbed the “Super” SAFER (Simplified Aid For EVA Rescue). This capability enabled the crewmember to conduct an un-tethered EVA, but required anchoring to the surface and involved constraints on the number of allowable starts and stops to simulate propellant use. The second EVA mode involved the Astronaut Positioning System (APS), a simulated “robotic” arm that was attached to the fore of the SEV. The EVA crewmember controlled their position on the APS, while the SEV maintained position around the target. The APS constrained operational radius of the EVA crewmember, beyond which required a translation of the SEV.
Prior to the test most participants expected that the best position for a geologist would be in an EVA role. However, test results showed that using a geologist in the IV position held distinct advantages. All crewmembers identified the IV position as extremely important during delayed communications operations. The IV role enabled a crewmember to access science files related to the tasks at hand, or past tasks, which were not available to EVA crewmembers. Furthermore, the IV crewmember had access to each EVA crewmembers data in real-time, enabling comparisons. Thus, assigning a geologist to the IV role enabled this crewmember to provide scientific situational awareness to the team on the surface when this input was lacking from the SB due to communication delay. Additionally, sample collection protocols are time-consuming. An IV geologist located in the SEV, in close proximity with the EVA crew, had the ability to plan subsequent science tasks while the EVA crew completed sample and site documentation. This essentially enabled “expertise multiplication” in much the same way that professional geologists work with field assistants. Because these results differ from our expected results we conclude that future exploration strategies that include an IV role require further field testing.