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Larson Scanner

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About This MicroSim

The Larson Scanner is named after Glen A. Larson, the creator of the TV shows Battlestar Galactica and Knight Rider. This distinctive sweeping light effect was used for:

  • Cylon robots in Battlestar Galactica (1978)
  • KITT - the intelligent car in Knight Rider (1982)

This MicroSim recreates the iconic effect with 12 red LEDs that sweep back and forth with a fading trail.

How to Use

  1. Speed Slider: Move right for faster animation, left for slower
  2. Watch the red lights sweep left-to-right and back
  3. Notice the fading trail effect on adjacent lights

Technical Details

The effect creates visual persistence through:

  • Active light: Full brightness (255 alpha)
  • Adjacent lights: Medium fade (150 alpha)
  • Two positions away: Dim (80 alpha)
  • Inactive lights: Very dim (30 alpha)
  • Glow effect: Larger semi-transparent circles behind the active light

Lesson Plan

Learning Objectives

  1. Understand animation timing and frame-based updates
  2. Learn about alpha transparency and visual persistence
  3. Explore arrays and position calculations
  4. Practice responsive design patterns

Target Audience

  • Middle school students (grades 6-8)
  • High school programming classes
  • Maker/electronics enthusiasts

Prerequisites

  • Basic understanding of loops and arrays
  • Familiarity with coordinate systems
  • Introduction to timing and animation concepts

Activities

  1. Speed Exploration: Experiment with the slider to find the most realistic scanner speed
  2. Count the Trail: How many lights show the fading trail at any moment?
  3. Modify the Code: Try changing the number of circles or fade levels
  4. Build It: Create a physical Larson Scanner with LEDs and an Arduino

Discussion Questions

  1. Why does the fading trail make the animation look more realistic?
  2. How would you modify this to have multiple scanners?
  3. What other pop culture references use similar lighting effects?

Extension Project

Build a physical Larson Scanner using:

  • Arduino or Raspberry Pi Pico
  • 12 red LEDs or NeoPixel strip
  • Shift registers (74HC595) for LED control

Sample Prompt

Create a p5.js sketch for a simulation of a Larson Scanner.
The project has a row of 12 red evenly spaced horizontal
circles that fade in and out like Cylon robot eyes.
A slider below the drawing area allows a user to control
the speed of the animation. Keep the background black
for contrast with the red lights.

References

  1. Larson Scanner on Hackaday - Hardware projects and tutorials
  2. Glen A. Larson on Wikipedia - Creator of the original effect
  3. Knight Rider KITT - The famous AI car with the scanner
  4. Arduino Larson Scanner Tutorial - Build your own with LEDs