Wheel and Axle — How Robot Cars Move
A WHEEL AND AXLE is two parts working together. The WHEEL is the round outer part. The AXLE is a thin rod through its center. They turn together. By turning the axle slightly, you make the wheel turn fully — moving objects with much less effort than dragging them.
How robot cars use wheels. A motor turns the AXLE. The axle turns the WHEELS. The wheels push against the ground, and friction makes the car move. Two wheels on each side: usually one is powered, one rolls free, OR both are powered with different speeds (this is how robots steer — one side faster than the other turns the robot).
Why are WHEELS used to move loads instead of just dragging them on the ground?
Different wheels for different jobs. SMALL wheels turn fast — good for slow, precise robots. LARGE wheels cover more distance per turn — good for fast robots. WIDE wheels grip soft surfaces (sand, mud). NARROW wheels are good for hard floors. Some robots use OMNI-WHEELS (special wheels with rollers) so they can move sideways. Robot car design is all about choosing the right wheels for the terrain.
Roll Test
Take a toy car. Push it on a hard floor — how far does it roll? Now flip it upside down and slide it the same way — how far does it slide? The big difference shows you the power of wheels.
Wheels are one of humanity's greatest inventions, and robots can't live without them. Every robot car, rover, and delivery bot rolls on wheels — usually with motors driving the axles.
Want to keep learning?
Sign up for free to access the full curriculum — all subjects, all ages.
Start Learning Free