Thames & Kosmos DLX, Руководство по эксперименту, Страница: 28 / 132

Using the robo-beetle
to balance a container
of water
YOU WILL NEED
› The assembled robo-beetle
› IR remote control
› 2 square frames
› 2 red anchor pins
› 5 AA batteries or 5 AA rechargeable batteries
› Box (see page 127)
› Screw-on cap from a water bottle
› Some water
› Dish cloth
HERE’S HOW
1. Familiarize yourself with the robo-beetle’s controls.
Can you make it go forward and backward? And in a
circle? Then you’re ready to start!
2. Place a square frame somewhere on the floor of your
room far away from the beetle.
3. Set a box on its narrow edge on top of another square
frame placed on the floor in front of the robo-beetle.
Have the beetle approach the box and grab it.
4. Turn the beetle a little and carry the box to the other
square frame.
5. Now it’s time to raise the level of difficulty. First,
though, you will have to take your robo-beetle outside
or to a room that can handle a little spilled water. The
bathroom would be best for that.
6. Stick the two square frames together with two red
anchor pins and lay them flat on the floor. Then set the
box on top of the frames.
7. Fill the screw-on cap almost to the brim with water,
and set it on the box. Now, have the beetle move
toward the screw-on cap and grab it.
8. Turn the beetle a little and carry the screw-on cap to
another location in the room that you have selected as
your goal. If you manage to get there without spilling
any water, you are the champion!
WHAT’S HAPPENING
If you take a look at one of the long sides of the beetle,
you will see how the red gear wheel meshes with the
blue one. The two together form a gear drive.
This kind of transmission has three main tasks:
1. To transfer force to a different axis: In the case of
our robot, the force is transferred from the motor
shaft with the red gear wheel to the blue gear
wheel for the legs.
2. To change the speed of rotation: You can
change the speed at which two gears turn by
using gears with different numbers of teeth (see
Experiment 8).
3. To change the direction of rotation: When the
red gear wheel turns to the left, the blue one
turns to the right, and vice versa.
DID YOU KNOW?
How can you transfer force without
changing direction? It’s simple: Just insert
a third gear wheel between the other two.
Try it yourself.
EXPERIMENT 3
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