Challenge: Repetitive L – Accuracy Challenge

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Participants: Team              


Objective: To draw an L shaped line 10 times with the marker stopping within a 2-inch diameter circle.  Each leg of the L should be about 30 inches long.


Points Possible: 100

Rules and Procedures: 


You will need about a four foot by four foot white board that can be laid on the floor. You should use a dry erase marker with a rubber band to hold it to your assembly.

  1. The robot can start anyplace on the white board.
  2. You need to make an approximately 90 degree turn.  The legs should be perpendicular to each other.
  3. Each leg of the L should be about 30 inches long.
  4. You have unlimited time.
  5. The 10 lines need to be consecutive.
  6. Minor pen skips are ok if it is easy to see where the line and stopping place are.
  7. You pick up the robot at the end of the L shape and you reset it at the beginning.
Grading Guide: 


  1. You get unlimited attempts to do the challenge correctly for full points
  2. If the stopping points are inside a 3-inch circle you can get 90 points.
  3. If the stopping points are inside a 4-inch circle you can get 80 points.
  4. If the stopping points are inside a 5-inch circle you can get 70 points.
  5. If the stopping points are inside a 6-inch circle you can get 60 points.
  6. Scores under 60% are not acceptable and you must keep trying.


  1. You can practice as much as you want. 
  2. Tell your instructor when you have an official attempt.  Your instructor should be able to clearly see your stopping points.
  3. You can slow your robot down using gears.
  4. If your wheels are slipping you may want to clean your wheels or the surface of the white board.
  5. Friction can make a big difference on this challenge.  There are a lot of places that friction can affect your robot performance.  The friction of the pen on the white board can also be a factor.
  6. The way you position your robot at the start will significantly impact where it ends.
Education Level: 
HW Platform: 
SW Platform: