” Lunar regolith is fluffy due to the low gravity and lack of a lot of weathering procedures, and the particles are sharp like broken glass,” said Arno Rogg, a rover movement system engineer at NASAs Ames Research Center in Californias Silicon Valley. “Rocks of numerous sizes are spread everywhere on the Moons surface area. All that provided some genuine engineering challenges to creating a light-weight, performant, and robust wheel for the half-ton rover.”
To evaluate if their wheel was all set for the Moon, the group dealt with ProtoInnovations of Pittsburgh. The robotics company, which likewise designed software controls for VIPERs wheels, is working to improve rover driving ability in extremely variable and unknown lunar terrain. Their work is supported by NASAs Small Business Innovation Research and Small Business Technology Transfer program.
Georgia Crowther, a robotics hardware engineer at ProtoInnovations, prepares the surface for VIPERs wheel to roll through a series of tests gauging its toughness and to study the rovers mobility. The simulated lunar regolith, or soil, is tamped down to provide a constant surface and a “clean slate” in which to study the wheels tracks, its traction efficiency, and how it maneuvers over rocks.
At the ProtoInnovations laboratory, engineers connected one of VIPERs wheels to the narrow, 20-foot-long lunar sandbox equipped with determining devices, cams, and robotic controls for imitating slipping and sliding. The wheel rolled slowly backward and forward under conditions that simulated as closely as possible what it will experience on the Moon.
Well-defined slopes were produced in the lunar soil simulant, and the wheels tracks were studied after any substantial slip. Sensors let the team step just how much the wheel sank into the soil, its traction efficiency, and how it navigated over rocks.
” Simulating on Earth the method the rover will carry on the Moon needed complex robotic controls– however thats what we do,” stated Dimi Apostolopoulos, CEO of ProtoInnovations. “Our most significant obstacle was picking simply the best rocks to stand in for Moon rocks in the test bed.”
Goldilocks Moon Rocks
Actual samples of Moon rocks are, of course, too valuable to utilize for a rover test drive, and the terrestrial stand-ins needed to be just right. Too soft or too hard and they d give an incorrect impression of the challenge the rover will face.
The team secured some of the uncommon Earth rocks that many carefully resemble the Moons, and, by reducing genuine information about the circulation of lunar rocks, learned the number of what size should be used in the test bed. They also learned how to area them so the wheel experienced striking rocks the way it will throughout VIPERs objective.
In all, the wheel was put through 196 scenarios of different rock shapes, heights, and places the rover is most likely to discover on the Moon.
” Overall, the wheels efficiency was outstanding,” stated Rogg. “At the end of the test, both its physical condition and its behavior– looking especially at its traction– were just somewhat deteriorated compared to when we began the test. By driving the wheel more than twice the distance its expected to travel on the lunar surface area, we reduced the danger of any premature wheel failure occurring on the Moon.”
Small weaknesses spotted in the wheels during screening were attended to by VIPERs mechanical style group with improvements that went into the rovers final design. VIPER will be delivered to the surface area of the Moon in late 2023 as part of the Commercial Lunar Payload Services initiative.
VIPERs wheel maneuvers over a rock throughout endurance screening for the rovers wheels. Their sizes, shapes, and placement in the test bed were thoroughly selected using real data about the circulation of lunar rocks, so the wheel would experience hitting rocks the method it will throughout VIPERs mission. The all-metal wheels of the Volatiles Investigating Polar Exploration Rover, or VIPER, will have to endure a whole lot of rolling and rocking as they move throughout the rugged lunar surface area. They simulated slopes, wheel slips, and even the size, shape, and distribution of rocks the rover will encounter on the Moon.
By driving the wheel more than twice the distance its expected to travel on the lunar surface, we lowered the threat of any early wheel failure taking place on the Moon.”
VIPERs wheel maneuvers over a rock during endurance screening for the rovers wheels. Their sizes, shapes, and placement in the test bed were thoroughly chosen using real data about the circulation of lunar rocks, so the wheel would experience hitting rocks the way it will during VIPERs mission.
The all-metal wheels of the Volatiles Investigating Polar Exploration Rover, or VIPER, will have to hold up against an entire lot of rolling and rocking as they move across the rugged lunar surface. The tests helped solidify plans for the wheels and provided engineers a chance to study its motions, in the name of creating even much better mobility controls for future rovers.
Using a Moon-mimicking set-up in the laboratory, the VIPER group evaluated one of the rovers wheels over a three-week duration. It clocked 25 miles of movement in a modern sandbox filled with lunar soil simulant, running through a battery of tests. They simulated slopes, wheel slips, and even the size, shape, and circulation of rocks the rover will encounter on the Moon.
A wheel from NASAs Volatiles Investigating Polar Exploration Rover, or VIPER, is run through endurance testing in a test bed consisting of lunar soil simulant and a few of the most Moon-like rocks on Earth, at ProtoInnovations in Pittsburgh. Credit: ProtoInnovations, LLC
While NASA has significant experience designing Mars rovers, engineers needed to create brand-new technology for controlling VIPERs wheels in the untouched environment of the Moons South Pole.