Innovative Robustness Analysis on a Mars Lander Airbag
During the development of a robotic planetary spacecraft, Astrium, a division of EADS and Europe's leading space company, required design support to ensure that the unmanned vehicle would land safely on the surface of Mars. The landing of robotic spacecraft on Mars is a risky undertaking with approximately half of all attempts ending in failure. A vented airbag solution was decided upon but this carries the challenge of stabilizing the altitude during the landing to prevent roll-over while at the same time preventing excessive rebound.
Altair ProductDesign was selected to optimize the airbag, assessing its design to maximize its performance and the chances of a successful landing. Using Altair's own HyperWorks virtual simulation tools, Altair ProductDesign studied the airbag's height, diameter, pressure and vent size and their influence on the craft as it impacts on Mars' surface. Due to the highly varied nature of the planet, the design needed to consider the effects of the craft landing on a variety of surfaces such as flat ground or rocky terrain, potentially under heavy wind and from numerous descent angles.
By taking these potential situations as design variables, Altair ProductDesign was able to suggest an improved design that offered a much higher chance of a successful landing. The new design method allowed EADS to gain a greater understanding of the effects of landing on various terrains and at different landing angles which could be used to further improve the overall design and likely success of the project.Result
The robustness study identified a potential failure that had not been anticipated by the design team originally, where the trailing edge of the inclined airbag makes contact first as it impacts at an angle causing the lander to be pitched into a roll. This in itself was a valuable discovery of the project and helped identify future improvements. The overall probability of a successful was increased from 69% to 80% as a result of this project. The Mars lander project is still ongoing at EADS with plans to launch the spacecraft later this decade.