To Boldly Go Where No Robots Have Gone Before–Part 1: EELS Robot to Spearhead a New One-Shot Exploration Paradigm with in-situ Adaptation

Historically, robotic space exploration has been conducted in a sequence of incrementally more sophisticated missions, starting with flyby and orbiting, followed by simple landing and roving missions, and eventually leading to more complex robotic missions involving long-range driving, drilling, or sample return. The benefit of this approach is that capabilities can be specifically designed for narrowly defined environmental conditions. For example, the development and V&V of the complex robotic functions of NASA’s Mars rover Perseverance, such as autonomous driving and the sampling and caching system, were heavily informed by the environmental knowledge gained from previous Mars missions. However, now that NASA is destined to explore a multitude of more challenging worlds, we will likely not enjoy the luxury of sending a series of spacecraft to the same destination due to budgetary constraints, a scarcity of flight opportunities, and the extensive cruise time to the Outer Solar System and beyond. We argue that a new robotic exploration paradigm will be needed, which replaces an incremental exploration campaign with a single-shot mission where a robot or a team of robots adapts its behavior after arrival and increasingly elevates the level of behavioral complexity as it learns about the new environment. A key enabler of such adaptive one-shot exploration is highly versatile robotic hardware combined with onboard intelligence. We have developed a snake-like versatile and intelligent robot, namely the Exobiology Extant Life Surveyor or EELS, which would enable access to the subsurface oceans of icy moons by descending into an erupting vent, such as those on Enceladus. By combining its high-DOF mechanical system (Gildner, et al. 2024), active skin propulsion system (Marteau, et al. 2024), and the new adaptive autonomy software framework called NEO Autonomy (Thakker, Paton, et al. 2023), we demonstrated through numerous lab and field tests that EELS can locomote in a wide range of environmental conditions, including sand-covered surface, undulating ice, high-slope snow, and vertical glacial shafts, by switching between significantly different mobility gaits. It is particularly notable that EELS achieved ~1.5 m fully autonomous vertical descents in the natural ice moulins of Athabasca Glacier in Canada. This paper first highlights the limitations of the current incremental exploration paradigm and builds an argument for the adaptive, one-shot exploration paradigm by drawing insights from a number of flight and research projects. We will then provide a broad overview of the vision, technologies, scientific impacts, capabilities, and field test results of EELS, while the three companion papers (Gildner, et al. 2024), (Marteau, et al. 2024), and (Thakker, Paton, et al. 2023) provide the detailed description of the hardware, active skin propulsion, and autonomy systems of EELS, respectively