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Comment by foobarbecue | Hacker News Reader

Indeed. I'm a rover driver & arm operator on Curiosity and there have been a few sandy patches where things were a little ... touch and go. I often think: what if I made a bad call, and my drive ended the mission? Even with a mission that's been operating for more than 10 years, it would be awful: there are hundreds of people involved, including scientists who have been planning investigations for the rover to conduct along our journey over the next few years. I would feel terrible if it was my fault that we never got to their research site of interest.

But then I remember: I'm not an airline pilot. I'm not a surgeon. Yes, my decisions matter, but this is not the highest-stakes job out there, not by a long shot.

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You’re driving a ‘car’ on Mars!

Does it actually include touch and go like driving with the driver as decision maker? I expected that every move would be scrutinized by a team of specialists?

In a nutshell, one rover planner (that's what drivers / arm operators are called) writes the sequence of commands, a second rover planner checks it and then walks through it line-by-line out loud with another ~2 rover planners watching. Then the second rover planner walks through the whole thing again with many other teams listening in and asking questions.

The first rover planner also consults with a surface properties scientist during development of the drive command sequence.

So, if things go wrong it's never really any single person's fault. But still, that first rover planner drafting the initial version of the command sequence bears a fair amount of responsibility.

Just wanted to add that if you're a US taxpayer, that's your car we're driving. We really do try to take good care of it :-)

Considering the relatively small size of the budget that might be the most carefully managed bit of taxpayer money in the entire country ;)

Just wanted to say that this is the kind comment chain I come to HN for, when a Mars rover driver comes in with a relevant and amazing anecdote. Absolutely love this. Thank you foobarbecue!

Aw, shucks. If you're interested in more info, there's a paper about how we work: https://doi.org/10.1109/AERO50100.2021.9438370 , the mission blog is https://mars.nasa.gov/msl/mission-updates/ and this reddit channel is great: https://www.reddit.com/r/curiosityrover/ .

this is fascinating.. thanks for the insight!

The rover has a bit of autonomy so it won't drive itself off an unseen cliff or whatever, right?

The autonomous driving capabilities on Curiosity (known as "guarded" and "autonav" modes) are quite limited and haven't been used recently. They don't work in rough terrain, and we've been in rough terrain for a while now. This means that we can only drive to the end of the 3D meshes generated from images from the previous parking spot. When the terrain is acceptable for autonav we can usually rely on orbital imagery and drive farther.

We do set limits on suspension angles and tilt of the rover. So we'll say "stop driving if you are tilted more than 20 degrees," "stop driving if your differential angle goes above 7 degrees," etc.

Thanks for explaining this. Super interesting stuff. It’s the type of comment I love to read here.

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