Light-Following Paper Bot
Build a paper bot with two light-sensing 'eyes,' write the rules that steer it toward a flashlight, and test how well your rules work.
Materials You'll Need
- This printable sheet
- Pencil
- 2 paper towel or toilet paper tubes (or rolled-up paper)
- Tape
- A flashlight
- 1 friend or family member to hold the light
- A dim room with space to walk
Hi, Bot Track Projects · light-following-paper-bot · Print-friendly · hibot.space/track-projects
How It Works
- 1
Tape the two tubes side by side, angled a little apart, so you can look through both at once. These are your bot's left and right light sensors. You are the motors.
- 2
Write a rule card with 4 rules. Example: 'If the left eye is brighter, turn a little left.' 'If both are the same, step forward.' 'If both are dark, spin a quarter turn.'
- 3
Your partner stands somewhere in the room with the flashlight on. Start across the room, look only through the tubes, and follow your rules one step at a time.
- 4
Run 5 trials with the light in a different spot each time. Count the steps to reach it in the trial log.
- 5
Change one rule (for example, turn more, or step less) and run 2 more trials. Did it get better or worse?
Your Work
Sketch your bot, write your rule card, and fill in the trial log. Write which rule change helped.
Paper bot design
Rule card
| If the eyes see… | Then the bot… |
|---|---|
Trial log
| Trial | Where the light was | Steps to reach it | Reached it? |
|---|---|---|---|
One rule I changed and what happened
Parent Notes
This is how a real light-following robot works: two sensors, compare the numbers, turn toward the bigger one. No map and no plan, just rules, and it still looks like it 'wants' the light. Keep the flashlight still during a trial. Ask: 'What happens if the light is behind the bot? Which rule handles that?'
Reflect
What did you learn? What was hard? What would you do differently next time?
Made by Hi, Bot. Learn more at hibot.space/track-projects