Spring 2011‎ > ‎

Speed and Wheels

Learning Goals
  • Understand how motor power affects speed.
  • Understand how wheel size affects speed
  • Understanding how to allow for different size wheels in programming
  • Understanding how to calculate speed
Build your Robot:  
  • Go to nxtprograms.com and make the Five Minute Bot
  • Click on Building Instructions.  
  • Follow instructions to build your robot
If you're new to robotics or are feeling rusty, click on this link to review the basics.

Variables that Affect Speed
  • How can you control the speed of your robot?  What variables do you have control over?
    • Whiteboard your ideas with your partner and mentor
Speed and Programming
  • Program your robot to go a distance of 12 tiles
    • Whiteboard this calculation with your partner and show your mentor your results
  • Change something in your PROGRAM to show that the speed is changed
    • Here's an example program
Degrees and speed are located in the Modifiers Palette.  The motor icon is located in the Wait For Palette.

Speed and Wheel Size

You will have three wheels to work with.

Distance - Correct distance for wheel size
    • Each wheel will require a different entry for the number of degrees
    • Whiteboard the calculation for each wheel so that your robot goes 12 tiles.
    • For each wheel, your program will have a different value for # of degrees.
    • Distance - Measure with a meter stick the length of 12 tiles in cm
    • Predict the speed for your robot to go 12 tiles with the three different wheels.
      • Whiteboard which wheels are slowest, middle, and fastest
      • Record your predictions in your journal
    • Test speed for different wheel sizes for three different wheels.
      • Time - Use a stop watch to measure the time for each wheel
        • Repeat 3 times for each wheel and take the average 
        • average = (time1 + time1 + time3)/3
      • Record your results in your journal
      • How did your results agree with your predictions?
  • Get your robot through the figure 8 course
    • Program your robot to go around both mountains
    • Fastest time wins