Instruction Guide: Line Racer

This lesson ties together all the learning to date. The students must design, build and program a line-following robot which is  driver-controlled through a wired remote control with a throttle and up to two sensors.

This "Problem Solving with Programming" pdf  from the "Challenges" page in "NXT Video Trainer 2.0" discusses the incremental design. This approach of breaking a large task down, and then incrementally designing/testing one piece at a time is a great antidote to most students' compulsion to jump right in at try to write a complex program all in one step. 

This Advanced Flow Charts PowerPoint describes using Process Blocks to design a hierarchical flow chart of a program.  Each My Block in a student's program would be a Process Block in their flow chart.  Insisting on a hierarchical flow chart as part of the Planning step before NXT-G coding (Prototyping) begins will greatly aid in the software design. 

Line Racer Challenge

This challenge specifications are laid out in the Line Racer Task Assignment Sheet:

  • A basic line follower with a wired throttle control is the minium requirement
  • By using two touch sensors on the wired remote control  the robot could switch between up to 4 possible modes:
    • high speed mode for straight aways
    • slower for shallow turns
    • very slow for sharp turns
    • switch sides of the line
    • other ideas to optimize performance
  • Students could also experiment with Math blocks (see Calucations Lesson) to further optimize the robot performance

Have students document the steps of the Engineering Process (restate challenge in their own words, identify related web sites, etc.) that they use in developing their robots. This Engineering Process Log Word hardcopy file may be used to document these steps in writing, or this electronic version may be used for a softcopy.

Conduct a double-elimination drag racing tournament (so each team races at least twice).  This site may be used to create an on-line race bracket, or this one for printed format.