Locomotion
Mars Rover Rescue
Guided by Marc Raibert
Your robot rover is stuck in a Martian crater. The wheels are spinning. Help it find a way out without getting flipped.
Watch
See it happen in the real world.
NASA's Perseverance rover has six aluminum wheels and 19 cameras. Every time it drives, it picks a path by looking at the rocks ahead and asking, 'Can my wheels handle that?' Real Mars rovers go slow on purpose — about 152 meters per hour, slower than a kid walking. The slow speed gives the rover time to think between moves. Engineers at JPL practice every rover drive in a sandbox on Earth first. That sandbox is called the Mars Yard.
Watch this
NASA JPL
Mars in a Minute: How Do Rovers Drive on Mars?
How JPL drivers map a route, then send commands across millions of miles.
NASA JPL
Perseverance Rover Camera View of a Long Autonomous Drive
Onboard footage of Perseverance navigating Mars on its own.
NASA Science
Rover Ride-Along in the Mars Yard (360 Video)
Drive alongside an engineering rover in JPL's Earth-based Mars sandbox.
Think
A question worth sitting with.
If your rover hit a rock taller than its wheel, would it be smarter to drive faster, slower, or turn?
Build
Make something with your hands.
Build a rover out of LEGO or cardboard with four wheels. Make the wheels big — the bigger the wheel, the bigger the obstacle it can climb over. Test it on a pile of books to simulate the crater.
Step-by-step
Cut a rectangular base out of cardboard — roughly the size of a paperback book. This is your chassis.
Find or make four wheels at least as tall as your thumb. LEGO wheels, jar lids, or thick cardboard discs all work.
Attach the wheels using skewers, straws, or LEGO axles so they spin freely. Loose wheels are good — rovers need to twist as they cross uneven ground.
Tape your weight (battery pack, jar of coins, anything heavy) in the middle, not at the back. Where the weight sits decides whether your rover tips.
Stack three books to make a 'crater wall' about 5 cm tall. Drive the rover straight at it.
If it flips: move the weight forward, or make the wheels bigger. If it stalls: try a smoother surface. Note every change.
Toolkit
- LEGO
- Household
Play
Test it. See what it does.
Set up an obstacle field on the floor with three different objects: a flat coin, a thick book, a balled-up sock. Drive your rover across each and predict which one it will climb.
Challenge
Push it a little further.
Modify your rover so it can climb over a 5 cm obstacle without flipping. Try changing the wheel size, the wheelbase, or where you place the weight.
Reflect
Notice what your robot taught you.
What surprised you about how your rover handled the obstacles?
Also ask yourself
What surprised you?
Reward
Mission outro
+0XP
“NASA engineers solve problems just like this for the Mars rovers.”
Skills advanced: wheels, balance
Badge
First Robot Builder