Mission 3  ·  Hints

The S-Curve

Open one hint at a time. Try it before you open the next.

Hint 1 — Think about it
At every wall, ask two questions: Is my right open? Is my left open? Ahead is already blocked — that is why you stopped. Do not measure how deep a corner is; only whether there is more than a lane width of room.
Hint 2 — Which blocks to use
repeat until < color sensor sees green >The main loop — you do not know how many turns there will be.
motor ( C ) go to position ( 90 / -90 / 0 )Swings the turret: 90 = look right, -90 = look left, 0 = ahead.
distance sensor B is farther than ( ) cmTrue when there is room to move = open.
set ( right_open ) to < … >Remember what you saw, then decide.
if … else if … else …Right first, then left, then dead end.
Hint 3 — Plan in plain words
  1. Loop until green.
  2. Drive until a wall is close ahead (or green).
  3. Stop. Turret right: is it open? Turret left: is it open? Turret back to ahead.
  4. Right open: turn right. Else left open: turn left. Else: turn around.
  5. When the loop ends: play the sound.

Watch out: Swing the turret slowly and wait a moment before you read the sensor — it needs time to settle. And measure your own numbers: how far is the wall when the car is centred, and how far is an opening?

Playbook: Stop and look · Open or blocked? · The right-hand rule · Green means go

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Printable version: mission-3-hints.pdf