A new state-of-the-art Mars Yard, a testing ground for Mars rovers, was recently opened in southern England. The new Mars Yard is a big facility, three times the size of the previous one. Built by Airbus Defence and Space and located in Stevenage, the facility is intended to replicate Mars conditions. The ExoMars rover, expected to launch in 2018, will have prototypes test in the Mars Yard prior to the finalization of its navigation system. The new Mars Yard is larger so the ExoMars rover can demonstrate the ability to autonomously operate across large distances. Because of the distance between Mars and the Earth, the robot will not be able to be controlled in real-time, a lag of approximately 10 minutes would occur for each command.
The rover will be tasked with attempting to find signs of either present or past life on the planet. Once landed on the planet, the ExoMars rover will be given a destination to reach by controllers on Earth. The rover will use its onboard computers and cameras and independently figure out the best route to take to get there. The Mars Yard will be used to develop and test the algorithms necessary to make sure the systems in the ExoMars rover are able to perform at optimal functioning levels.
The six-wheeled rover will have the capability to navigate autonomously up to 230 feet each day with no external control. The rocker-bogie suspension will allow it, like previous rovers sent to Mars, to travel through the Mars sand and climb over small rocks. While the Mars Yard will simulate the terrain of the planet, it is not capable of matching the planetary gravity. To compensate, engineers have made a number of prototype rovers of a different weight. The gravity on Mars is approximately 38% of Earth’s gravity and so the prototype rovers which will be tested in the yard will be weighted accordingly.
Additionally, the lighting and atmosphere are different from that on Earth. One of the new features of the testing site is the Mars-simulated lighting system. Systems Engineer Paul Meacham states that there are about 60 different lights which have been selected for correlation to the light spectrum found on the planet Mars. The lighting system has not only taken into account the lighting spectrum but the intensity of the lighting, as well. The different scenarios of Martian lighting, including shadows, have been taken into account. This is crucial for the correct development of the autonomous navigation system of the rover as it will be navigating via camera. In order for the ExoMars rover to be able to navigate effectively, the cameras must function at peak performance levels in the alien environment. The Mars Yard will be critical for the development of the cameras.
The testing results of the prototype rovers and the technologies formed will be built into the actual Mars-bound rover. The ExoMars rover which will actually land on the planet will never be the one to test in the Mars Yard. The yard, with its simulated Martian landscape, will be used only with machines intended for testing and application purposes. The actual ExoMars rover will be built in a sterile room in order to make certain it remains clean and does not pick up any Earth contaminants. Any contamination from Earth could confuse the rover’s sensors as it performs its task to search out current or past life on Mars.
By Dee Mueller
on twitter @TuesdayDG