Navigating and moving around Mars is hard, and without being able to be in constant contact with Earth the ExoMars Rover has to look after itself.
Scientists on Earth cannot control its direction and drive it around. Every message to and from Earth to Mars can take 20 minutes to arrive – that’s hardly a quick call – and there are only one or two opportunities to communicate each day.
Basically, the ExoMars Rover has to look after itself most of the time – and that includes most of the navigation.
So designers are ensuring that the ExoMars Rover will be one of the most independent robots ever built for space exploration. Once it’s got the target location, it can even choose its own route.
Its navigation system uses 3D cameras on top of a mast – that helps it to see in much the same way as we do. The cameras map the safest and fastest route to a target destination, as well as keeping an eye on the rover itself. The images are used to make a map and plot a safe route.
Of course as it travels the terrain will change, so every moment that the rover is travelling it’s answering the following questions – where am I? What’s in front of me? Where do I need to go? What’s the best route? How’s my driving?
It creates maps that highlight areas where they may be risks, and areas where it should be safer to travel. It plots a safe route metre by metre, and sets off.
As the ground on Mars is rocky and hilly the ExoMars Rover has six wheels to help it get around and keep upright. Each wheel is made of a metal called titanium and can be steered independently and even pivoted – that’s made to rise and fall – which means it can stay level no matter how rocky or soft the ground.
The ExoMars Rover can travel at a maximum speed of 2 centimetres per second on the flat, and over a day could travel up to 70 metres per day when navigating itself. It’s expected to travel up to 4 km over the duration of the mission. Not bad for a robot all on its own!
You can hear Deep Space High: Destination Mars on Fun Kids Radio or listen to the series below!