Traverse Performance Characterization for the Mars Science Laboratory Rover

Abstract

It is anticipated that the Mars Science Laboratory rover, named Curiosity, will traverse 10-20 km on the surface of Mars during its primary mission. In preparation for this traverse, Earth-based tests were performed using Mars weight vehicles. These vehicles were driven over Mars analog bedrock, cohesive soil, and cohesionless sand at various slopes. Vehicle slip was characterized on each of these terrains versus slope for direct upslope driving. Results show that slopes up to 22 degrees are traversable on smooth bedrock and that slopes up to 28 degrees are traversable on some cohesive soils. In cohesionless sand, results show a sharp transition between moderate slip on 10 degree slopes and vehicle embedding at 17 degrees. For cohesionless sand, data are also presented showing the relationship between vehicle slip and wheel sinkage. Side by side testing of the Mars Exploration Rover test vehicle and the Mars Science Laboratory test vehicle show how increased wheel diameter leads to better slope climbing ability in sand for vehicles with nearly identical ground pressure. Lastly, preliminary data from Curiosity's initial driving on Mars are presented and compared to the Earth-based testing, showing good agreement for the driving done during the first 250 Martian days. C 2013 Wiley Periodicals, Inc.

Improving Slip Prediction on Mars Using Thermal Inertia Measurements

“…For the Mars rovers, operators predict slip by first identifying terrain class visually from Navcam imagery then estimating slip from average terrain slope using Earth-calibrated slip versus slope curves [24]. Recent work on Curiosity has improved this process for Curiosity using a CNN-based classifier to visually classify terrain and estimating slip using models learned from in-situ experiences on Mars [48].…”

“…Because there were few samples at high slopes, four syn- thetic samples were also added for training from the Earthcalibrated model [24]. Samples were added at the minimum slope with 100% slip, x max , and −x max with -100%.…”

Slide-Down Prevention for Wheeled Mobile Robots on Slopes

“…Mobile robot navigation on inclined terrains is required in challenging environments typically found in disaster areas (Zhang & Song, 2014), planetary surfaces (Heverly et al, 2013) or agricultural zones (Cariou et al, 2009). Even if special mechanisms have been proposed to improve mobility on steep slopes, such as leg-track hybrid locomotion (Nagatani et al, 2011), plowing tools for loose soil (Loret De Mola Lemus et al, 2014), or an onboard arm pushed against the ground (Serón et al, 2014), many ground robots rely on wheeled locomotion.…”

Folding Study on the Multi-constrain Quadrilateral Suspension of Six-wheeled Rover

“…In so doing, not only is the space of the rocket saved but also the rover is protected better [4][5][6]. The success of "Sprit" rover shows that the contradictory between multi-functions and small volume could be solved through employing folded technology into the design of rover locomotion system [7][8][9]. However, although some researchers have proposed some methods to guide the folded design for the rover suspension, the sound design theory has been not presented to date.…”