MSC Software's MD Adams Was Selected for the Simulation of NASA Mars Exploration Rover, Opportunity

MSC Software has announced that Washington University in St. Louis/Jet Propulsion Laboratory (JPL)/Massachusetts Institute of Technology (MIT) has chosen MD Adams to develop a multi-element dynamic model of the NASA Mars Exploration Rover, Opportunity, and its interactions with soil and bedrock while driving over realistic terrain models.

The model, named Artemis, includes both track and cross-track wheel stresses and torques as the wheels interact with terrain elements and sink into deformable soils. A single wheel model was also developed to better understand wheel-terrain interactions before simulating Opportunity's full six wheel drive system and complex rocker-bogie suspension system. The model is being validated with single wheel experiments and "Mars Yard" data using an engineering model of the rover driving over various terrains to simulate flight telemetry.

Opportunity Mars flight data are also being examined and compared to model results. Results examined include ripple crossing experiments in Meridiani Planum in which wheel sinking approached 5 cm and slippage 58%; hill climbing on bedrock thinly covered with soils, and skidding encountered when Opportunity drives down a soil-covered hill. The intent is to have a validated model available to simulate drives across the sloping and soil covered terrains when Opportunity reaches the rim of the ancient 20 km wide Endeavour crater. The rim exposes rocks older than any examined from the surface of Mars, and the steep, soil-covered slopes are expected to present mobility challenges.

Monte Carlo approaches will be used with MD Adams to simulate drives and path planning in order to choose the lowest risk way points to the ancient outcrops. The simulations will provide a new "tool" for selecting drive directions that minimize the probability of encountering conditions hazardous to Opportunity.

Professor Raymond Arvidson, Director of the Earth and Planetary Remote Sensing Laboratory at the Washington University in St. Louis says, "MD Adams has enabled us to move quickly in developing a fully dynamic model for the Opportunity rover with realistic wheel-soil interactions. The fully dynamic approach is the only way I can see for modeling actual telemetry from the rover during its drives, since there are six driving wheels and a complex suspension system that causes the wheel drive actuators to interact in non-intuitive ways to keep the rover on its course."

"We are very proud to be involved in such a cutting edge project such as Artemis," said David Yuen, Senior Vice President, Americas at MSC Software. "We are confident that our software and know-how will provide significant value to NASA and Professor Arvidson in the realization of Opportunity."

Raymond Ernst Arvidson, Ph.D. is recognized as a James S. McDonnell Distinguished University Professor at the Washington University in St. Louis. He holds a doctorate degree from Brown University and has authored several research publications on the topic of planetary geology. He is currently the Director of the Earth and Planetary Remote Sensing Laboratory, which is heavily involved in several integral aspects of NASA's planetary exploration endeavors such as developing science objectives and plans for missions, participating in mission operations and data analysis, and archiving and distributing data relevant to characterizing and understanding planetary surfaces and interiors.