Lever Robot Arm — Simple Machines for Robotics
A LEVER is one of the SIX SIMPLE MACHINES — basic tools that do the work of more complex machines. A lever has a stiff bar (the lever) and a fixed point it pivots around (the FULCRUM). Push DOWN on one end, and the other end goes UP. With the right design, a lever can multiply your strength enormously.
Robotic ARMS use levers everywhere. The PRINCIPLE: where the fulcrum is matters. Fulcrum near the object being lifted = LITTLE motion needed at the other end (think of a wheelbarrow). Fulcrum far from the object = MORE motion needed but you can move things faster (think of a baseball bat). Every robot arm joint is a tiny lever system.
You want to lift a heavy box with a lever. Where should the FULCRUM be placed?
Three types of levers. CLASS 1: fulcrum in the middle (seesaw, scissors). CLASS 2: load in the middle (wheelbarrow). CLASS 3: effort in the middle (your forearm — bicep is between elbow and hand). Robots use all three depending on what they need to do. Knowing levers helps you understand WHY robots are designed the way they are.
Build a Lever
Make a simple lever from a ruler and a pencil. Place the pencil under the ruler. Put a heavy object (a book) on one end. Push down on the other. Move the pencil — does pushing get easier or harder when the pencil is closer to the book?
Levers are 5,000 years old, but they still power modern robots. Understanding simple machines is the foundation for understanding any robotic mechanism — and most regular machines too.
Want to keep learning?
Sign up for free to access the full curriculum — all subjects, all ages.
Start Learning Free