NASA – Jet propulsion Laboratory

NASA – Jet propulsion Laboratory

NASA engineers used Femap to ensure Curiosity could endure the “Seven Minutes of Terror” 

JPL engineers use a toolkit of engineering software applications from Siemens PLM Software to help them make highly informed decisions. Virtually all of the spacecraft itself and its payload were subjected to simulation analysis using Femap for pre- and postprocessing.

Femap helps optimize component and parts for Curiosity’s mission to Mars, the most challenging and demanding ever

Sending a package to Mars is a complex undertaking

Delivering a roving science laboratory from Earth to the planet Mars requires meticulous planning and precision performance. You only have one chance to get it right; there’s no margin for error. Engineers and scientists at NASA’s Jet Propulsion Laboratory (JPL) at the California Institute of Technology had to make crucial decisions thousands of times over a multi-year product development schedule to successfully land the Mars Rover “Curiosity” on the floor of Gale Crater on August 6, 2012.

JPL engineers use a toolkit of engineering software applications from Siemens PLM Software to help them make highly informed decisions. A key component in this toolkit is Femap™ software, an advanced engineering simulation software program that helps create finite element analysis (FEA) models of complex engineering products and systems and displays solution results. Using Femap, JPL engineers virtually modeled Curiosity’s components, assem¬blies and systems, and simulated their performance under a variety of conditions.

From 13,000 to 0 mph in seven minutes 

Also known as the Mars Science Laboratory (MSL), this rover is massive compared to earlier vehicles NASA has landed on the “Red Planet.” In the deployed configuration with the arm extended, the rover is 2.5 meters wide, 4.5 meters long and 2.1 meters high. Weighing nearly a ton, the Curiosity rover is five times the mass and twice the length of its predecessors, which meant that an entirely new and much softer landing procedure had to be engineered. 

NASA needed to slow the rover spacecraft from a speed of 13,000 miles per hour (mph) to a virtual standstill to softly land the rover during what NASA calls “Seven Minutes of Terror.” After completing a series of “S” maneuvers, deploying a huge para-chute, and then with the unprecedented use of a specially designed “sky crane,” the MSL was gently set down so as not to damage the labs’ functional and scientific components.

The role of Femap

Virtually all of the spacecraft itself and its payload were subjected to simulation analysis using Femap for pre- and post-processing. Simulations performed before part and system production included linear static, normal loads, buckling, nonlinear, random vibration and transient analyses. Thousands of design decisions were made using information from Femap simulations.

Femap is JPL’s primary pre- and postpro¬cessor for FEA. For MSL, engineers started using Femap early in the design stage when they were performing trade studies on various configurations or different ways to approach the mission. As the configura¬tion matured, they used Femap to help create the master finite element model that was used to run the various load cases.

Most of the structural analysts at JPL use Femap either for creating or viewing the results of a FEA run. The software was used for both high level-linear analysis and very detailed nonlinear analysis. These are two very different types of analysis both using the same piece of software.

Femap was critical in performing all types of FEA on all aspects of the vehicle. Each component of the vehicle had a higher-level, loads-type model built, and these models were joined to create the full spacecraft model. JPL engineers worked through various “what if” scenarios, includ¬ing as many as 37 different load cases for how the parachute would deploy during the landing process.

Virtually all of the spacecraft itself and its payload were subjected to simulation analysis using Femap for pre- and postprocessing. Simulations performed before part and system production included linear, static, normal loads, buckling, nonlinear, random vibration and transient analysis. Thousands of design decisions were made using information from Femap simulations.

Femap was designed as a very easy-to-use package, created for analysts by analysts who are acutely aware of what engineers need and how they work. They can pick it up after six months of non-use and be back to peak proficiency in a very short time.