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 The gearbox is an important part of the robot. It connects the motor to the axle. Wheels or cams attached to the axle make the robot move when the motor turns.

Gearbox housing The gearbox housing is made of a plastic called nylon. It is the same material from which plastic zips and some of our clothes are made. The gearbox is made by injection moulding.
Axle and Pinion Gear The axle is made of steel, a strong material that will not bend easily. Wheels or other components are connected to the ends of the axle. Over 5000 years ago carts with wooden axles were used to transport heavy materials.
Electric Motor The electric motor has a small worm gear fixed to the spindle. The worm gear connects to the pinion gear on the axle. The principle of the electric motor was first shown in 1821 by the British scientist Michael Faraday.
Clamping belt The clamping belt holds the electric motor tightly in the gearbox housing. The belt has a ratchet mechanism to stop the belt slipping open.

Now you have completed Lesson 3


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