GEARING – UP AND DOWN!

INTRO AND LEARNING GOALS
Gears can transform your robot! Just like on your bike, gears can help your robot go faster or climb those steep slopes. Sometimes the tricky bit is working out how to connect them to your robot.
In this lesson, we’ll find out how to add gears and get them working for us.
- Understand a simple way to connect gears to your simple robot
- Learn about ‘gearing up’ and ‘gearing down’
- Explore other gearing options available in your Mindstorms kit
GEARING UP AND GEARING DOWN
When a large gear is connected to the motor (the drive gear) and it turns a smaller gear (the output gear – maybe connected to a wheel), the smaller gear will turn several times for each rotation of the large gear. This means that the wheel will turn faster – this is ‘gearing up’ for speed.
When a small drive gear turns a larger output gear, the larger gear will turn fewer times for each rotation of the small gear and it will have more force (torque). This is ‘gearing down’ for torque.
LET’S DO A REALLY QUICK BUILD…
In this video Colin shows a simple way to ‘gear up’ to make our robot move faster. It is a great starting point and hopefully you soon will have your Mindstorms zooming round your kitchen classroom!

SOME TEACHING THOUGHTS… from Colin
- The gears do need to be connected solidly – especially when things start turning at speed!
- You can connect gears from just one large motor or from both – investigate to find the most efficient solution.
- Your Mindstorms set has several different gear sizes – try them out to see what happens.
- There are seemingly endless ways to add the gears to your robot – have fun experimenting!

ROBOT WORKOUT (WHERE NEXT?)
- If you’re looking for speed, you need to consider weight, aerodynamics, wheel size and rigidity – as well as gearing. Investigate the possibilities by rebuilding your robot in different ways.
- There are several other types of gears. Your Mindstorms set gives you the opportunity to use a WORM gear to change the direction of movement. You could also use the ‘funky black gears’ as we showed you in the Pick Up tutorial. I have also included their proper in that video!
- You could work out how to add a ratchet to your mechanism so that the gear only turns in one direction.
- Experiment with a really complicated series of gearing connections – just for fun!

GREAT SUPPORT FROM LEGO EDUCATION
DESKTOP:
You will need to download and install the SPACE CHALLENGE ACTIVITY PACK – https://education.lego.com/en-gb/downloads/mindstorms-ev3
From the lobby (the starting page) go to SPACE CHALLENGE and choose BASICS OF GEARS.
You will need to download and install the EV3 DESIGN ENGINEERING PROJECTS to your EV3 software by downloading it from here: https://education.lego.com/en-gb/downloads/mindstorms-ev3 and then choose BUILDING IDEAS / GEAR UP or GEAR DOWN.