NASA's tumbleweed-inspired rovers for large-scale planetary exploration

Citation

(2008), "NASA's tumbleweed-inspired rovers for large-scale planetary exploration", Industrial Robot, Vol. 35 No. 2. https://doi.org/10.1108/ir.2008.04935bab.007

NASA's tumbleweed-inspired rovers for large-scale planetary exploration

NASA's tumbleweed-inspired rovers for large-scale planetary exploration

NASA has had enormous success in exploring mars using traditional wheeled rovers. Sojourner was the first rover to successfully land and explore the martian surface and it was later followed by the larger spirit and opportunity rovers that are still operational today. However, the traditional rover design is limited to exploring areas that are nearby the landing site. Even though the larger rovers have explored much more of the planet's surface than Sojourner, there is still much of the surface remaining unexplored.

In order to explore larger areas that are further away from landing sites, NASA has been working on the concept of tumbleweed rovers that are powered by in situ resources, specifically the wind. The rover's design is inspired by nature and as the name implies the tumbleweed or Russian thistle (Salsola tragus). The actual prototypes that NASA has been testing for almost five years look more like large “beach balls.” These rovers are lightweight and can carry a number of scientific instruments over long distances. The tumbleweed rover moves by wind power which on the surface on mars achieves speeds of 2-5m/s during the day with gusting periods of 10-20m/s.

NASA has previously used the “beach ball” design during the pathfinder mission that delivered the Sojourner rover. It was not used in the rover but instead as a low cost landing method. The pathfinder mission used airbags to cushion the spacecraft's impact with the mars' surface during landing. The spacecraft traveled a considerable distance rolling on the planet's surface before coming to a stop.

Over the last few years, NASA has refined and improved the tumbleweed rover concept and they have also performed successful experiments with prototype rovers in the Antarctic. Recently, NASA scientists outlined the feasibility of using a team of tumbleweed rovers for the exploration of the Dao Vallis valley in mars. Dao Vallis is 1,200km long with gulley features that are believed to have been formed by water making it an interesting area for scientific exploration. To give you an idea as to why better locomotion methods for planetary rovers are necessary, NASA's twin rovers currently on mars can only travel a maximum distance of 100m or 0.1km a day. As you can tell, traditional rovers are not suitable for the exploration of large areas such as Dao Vallis and the tumbleweed inspired robots are a much better choice.