What Is a Motor and How Does a Rotation Sensor Work?
Electric motors convert electric energy to mechanical energy.Copyright (left) 2004 Microsoft Corporation, One Microsoft Way, Redmond, WA 98052-6399 USA. All rights reserved. (right) 2006 Eirik Refsdal, Wikimedia Commons
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Students learn about electric motors and rotational sensors. They learn that motors convert electrical energy to mechanical energy and typically include rotational sensors to enable distance measuring. They also learn the basics about gear trains and gear ratios. Students create a basic program using the LEGO® MINDSTORMS® interface to control a motor to move a small robot. Then, through a 10-minute mini-activity, they make measurements and observations to test a LEGO rotation sensor's ability to measure distance in rotations. This prepares them for the associated activity during which they calculate how many wheel rotations are needed to travel a distance. A PowerPoint® presentation, worksheet and pre/post quizzes are provided.
Electrical and mechanical engineers use motors to perform many tasks. Motors are used in a wide variety of machines, everything from pencil sharpeners to school buses. Knowing how motors work, including their internal components, such as rotational sensors and gears, helps students understand this fundamental, everyday device.
After this activity, students should be able to:
- Explain how a LEGO robot uses a motor and gears to move.
- Explain how motors rotate and enable motion by converting electrical energy to mechanical energy.