Construction: Wheels

Student Activity Instruction Sheet 1.7 Handout

 

 Wheels are used to make your robot mobile.  A wheel usually consists of a hub and a tire.  The type of wheel you choose will depend on what you want your robot to do.  Will it need to be fast or slow? Will it need to navigate on smooth or rough surfaces? Will it go up steep inclines or stay on a flat surface? Will it need to turn quickly and sharply?

 

Procedure 1:  Examining Wheels

1.      Take all of the wheel hubs out of the kits

2.      Take all of the tires out of the kit

3.      Examine all of the pieces and try to match up the hubs and tires by size.

4.      How did you match a hub and a wheel?

5.      Which size wheels do you think would make a vehicle go faster, larger or smaller?

6.      Do you think thicker or thinner tires would be best to make something go faster?

 

Procedure 2:  Speed?

1.      Split your team into two parts.

2.      One half of your team will locate these parts:

 

3.       Build this structure:

 

 

4.      The other team members locate these parts:

 

 

5.      Build this structure:

 

 

  

6.      Which vehicle does the team think will be faster?

7.      Have ONE person test our vehicles by rolling them together (the same person should roll both vehicles at the same time to make sure the force, or push is the same).  Switch people and try it several times.

8.      Which vehicle was faster?

9.      Does the size of the wheel matter when it comes to speed?

 

 

Procedure 3:  Large vs. Small

1.      Locate these parts:

 

 

2.      Build this structure;

 

3.      Test the speed.

4.      Is it fast or slow?

5.      What would happen if you changed the large tires for small ones - TRY IT

 

 

 

 

Procedure 4:  Swivel Casters

1.      Locate these parts:

 

 

2.      Build this structure:

 

 

3.      This is called a swivel caster wheel

4.      Now locate these parts:

 

 

 

 

5.      Construct this swivel caster.

 

 

6.      What is special about this kind of wheel?

7.      Which directions does it turn?

8.      When might you use this type of wheel?

 

HINT:  Caster wheels are usually used for balance or stability.  A swivel caster has one or more wheels attached to a pivot horn.  As they are not usually connected to a motor, they do not provide any steering or additional direction to a model or robot.

 

Procedure 5:  Challenge Diamond

The challenge diamond is one of the most stable wheel formations that you can build.  Try to construct a formation similar to this:

 


  1. Which directions could the model move?

  2. Did it seem stable or unstable?

  3. What kinds of things could a robot do that could move this way?