Introducing the Mars Challenge

Drove from Seoul to Daejeon by itself

At Mars Auto, we look for exceptional engineers. Traditional white board interview is designed to hire a diligent engineer. If smart enough people prepare for the interview for a few months, any of them can be hired at Google. This is not adequate for us because what we are doing usually requires an ability to solve problems with high uncertainty. We need to solve problems that we’ve never tried before. Then, how do we know if someone is exceptional? The best way to do this is to let candidates solve a hard problem. We want them to solve a hard problem alone. We are small. We lack resource. We do this all the time. This is not something that can be prepared. You cannot fake your ability when it comes to solving a real problem.

So here we introduce the Mars Challenge. Mars Challenge is a simple interview question at Mars Auto. If you are able to solve this, you are good enough to apply for us.

There are two video files.

1) train.mp4 is a video of driving containing 8100 frames. Video is shot at 20 fps.

2) test.mp4 is a different driving video containing 6173 frames. Video is shot at 20 fps.

There is a train.txt file containing the speed of the truck at each frame, one speed on each line.

Your deliverable is test.txt. E-mail it to

  1. This is an open-ended problem. You can use whatever you want to solve it.
  2. Please be warned that most solutions on the internet are wrong.
  3. MSE < 2 is acceptable. < 1 is good. < 0.5 is exceptional.
  4. Speed in the train.txt is not perfect. If you solve this right, there’s a chance that speed from your solution is actually more accurate than the one in the train.txt.