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image of student with Lego robot
Line Following Challenge

The Rules:
  • One minute will be allowed for setup and calibration before each round.

  • The robot must fit within the 18 x 18 cm starting box (no weight limit).

  • The maximum number of motors is two.

  • The maximum number of line sensors is two.

  • The robot must start with its sensors at the beginning of the outer line.

  • The team operator is only allowed to place the robot on the board and to push its starting button when told to do so.

  • The judge will time the robot.

  • If the robot leaves the line it will be given 3 chances (line crossings) to reconnect by itself within one vehicle length (~ 18 cm) of leaving the line. (The judge's decision on 'loss-of-line' is final.)

  • Each robot will be given two official trials at the line and the shortest time will be recorded.

  • The robot finishing the path in the shortest time will be the winner.

  • If two or more robots finish within 2 seconds, or no robots finish a run off will be declared between the best entries.

Game Board Description:

Image of the robotics challenge layout

  • The board is a 4 x 4 foot white enamel masonite board, the same material as used in Botball.

  • The board is edged with 1x2" pine furring strips (only needed for protection and for the Line Running Challenge).

  • The lines are made with standard 19 mm (3/4" black electrician's tape except for the two lines in the center, which are light green paper, attached with scotch tape. In some places the tape may be two layers thick (where tape overlaps).

  • The two centered lines are 21.6 cm long and 5 cm apart .

  • The sharp curves are 7.6 cm radius and broader curves are 15.2 cm radius on the inside edges.

  • The inner area is 64 cm x 64 cm and the space between parallel lines is 10 cm.

  • The circled numbers are not on the board, but identify the reference lines for the line running competition.

  • The two starting boxes are 18 cm x 18 cm and 10 cm apart, equally spaced with one edge on the inner edge of the outside straight line.

Robot Course Construction Tips:

  • Suggested method for accurate line layout: Measure and draw the inside edges of the tape as two concentric boxes on the board, then use a compass to draw the curves. Finally, lay the tape along the marked edges, taking care to not stretch the tape, as it tends to shrink back to its unstretched length.

  • You should try to make the board lighting as uniform as possible, but the entrants are responsible for calibrating out the local lighting effects on their sensors.

Sharing the Results:

If you would like to share the results of your runs or competition, please feel free to send Terry Grant with your data and other information regarding the challenge, or if you have any questions about what to send.

FirstGov NASA
Curator: Drew Price
NASA Official: Lucien Junkin
Last Updated: April 28, 2020
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