1. Lego Etch-A-Sketch Alma College – Lego Mindstorm Workshop – June 2005

2. Authors • Cathy Bareiss – Olivet Nazarene University • Gary Locklair – Concordia University, Wisconsin • Cate Sheller – Kirkwood Community College

3. Target Audience • Characteristics • Jr. High student through CS0 • Min. programming • via data files and simple drivers • Stationary brick • Worm gears • Geometry • IRX control of robot

4. Overview • Students will build a Lego Etch-A-Sketch robot and write simple programs via use of data points to use it to draw. • With this exercise students will learn to use geometry in the real world. They will also understand the importance of sequencing of commands and the need to plan first.

5. Problem • In Bareiss-Land a recent law was passed that all toys must be powered by electricity. Ambassador O’Horvath wants to import Etch-A-Sketchs to help her country’s economy. You have been hired to do the marketing of the new Lego Etch-A-Sketch. You must develop some prototypes to use in the marketing

6. Tasks • build robot (with instructions) • build data file to draw simple figures (i.e. square, triangle) • data file with more complex figures (polygons, ciricles?) • provide code to get a number from either touch sensors or buttons • have them adapt code to read from input (above) instead of data file for list of points

7. Proof of Concept • Prototype of robot

8. Things to be “supplied” • Program that can go certain lengths • Via time or rotation sensors • Instructions for building robot • Need guides to control “rods” • Need device to hold pen (possibly a rubber band) • Need to provide code for inputting number pairs via buttons (or touch sensors – need to adapt robot)

9. Different Levels • Simple level • Provide all code – require students to develop only the points • Intermediate level • Adapt code to take numbers read from buttons and develop appropriate driver • Advanced level • Adapt code to work with length and angles

10. Additional tasks • Use geometry to compute points for certain angles/figures/etc • Study accuracy • Develop a marketing plan • Adapt program to take angle and length • Build electric rule