I’ll be honest with you, this is not Mars.
But it’s one of the closest simulations we’ve got:
the Mars Yard, at NASA’s Jet Propulsion Laboratory in Pasadena, California.
This is where NASA tests out models of its rovers before they get sent to the Red Planet.
And over there is where NASA’s engineers can learn to drive one.
We have the Mars Yard, which is made of a few things:
some of them are rocks that we actually take to a lab to cook
and ensure that they have the exact same compositions,
and we bring it to the Mars Yard.
Other rocks are actually not the same composition
but the colour is the same, or the texture is the same.
And the same thing with the sand.
We bring sands from specific areas so that the colour and the texture matches.
Out here in the Mars Yard, there’s not just that simple model.
Over in that hanger, well, it’s not really a model of Curiosity:
It’s a full-size physical twin.
It’s not got quite all the electronics and there’s no plutonium,
but it’s close enough to figure out what to do in tough situations.
All the instruments, all the mechanisms that we have,
plus additional simulations, we put it all together
and we integrate it right here with Maggie.
80-90% is probably the same thing we have on Mars.
There’s a few things that aren’t.
For example, the wheels themselves.
The gravity is different on Mars, so you don’t want to have
the exact same thickness of material on the ones on Earth
otherwise you’re going to break them very easily,
and it’s not going to represent what actually happens on Mars.
So the intent is: try to dry-run everything that we can with this one,
try to simulate it, and then go for it on Mars.
Driving a rover comes with a strange problem: a time lag that,
depending on where Earth and Mars are in their orbits,
is anywhere between four minutes and 24 minutes.
This is not a case of just grabbing a joystick and powering forwards:
there is a lot of planning involved.
Because if you break that rover,
there are no spare parts and no second chances.
I’ve been driving rovers since 2004, so 13 years now.
I’m the person that has driven the most kilometres on Mars.
We can go from really low level commands,
say “apply 5 volts to a motor”, up to a command of saying
“go there and avoid all the obstacles that are in between”.
The vehicle not only has software on board to control the movement,
but most importantly, has software to determine if something bad is happening.
Every day we use the cameras to take pictures.
The images there — there they are — so we can reconstruct the 3-D terrain.
From those pictures, we can determine what activities we can do at that location
and where it is safe to drive.
On Curiosity, we have about 20 people that are certified to drive the vehicle.
We have different styles, different comfort levels,
in terms of risk or things that we are scared of.
Some of us are particularly scared of sand, steep slopes.
It depends on what problems you had when you were driving.
Every single day that we are going to spend with the rover on a specific site,
it’s very important for us to “test as you fly”,
and what I mean with that is: as much as possible, do it here,
because you don’t want to be surprised when you try it on Mars!
Thank you to all the team at the Mars Yard
and at the Jet Propulsion Laboratory.
Pull down the description for more about them and their missions.