🎲 Tilt Switch (Ball Switch)

📌 Description

A tilt switch is a small sensor that detects whether it is tilted or upright. Inside, it has a tiny metal ball that rolls and makes or breaks contact depending on the angle.

🎯 Use

In our projects, tilt switches are used to:

• Detect orientation (upright vs tilted).
• Act as a safety sensor (turn off if the robot falls).
• Trigger actions when the robot changes position.

👉 Think of the tilt switch as the robot’s balance sensor — it knows if the robot is standing straight or leaning.

Module parameters

Pin name	Description
G	GND (Power Input Negative)
V	VCC (Power Input Cathode)
S	Digital signal pins

• Supply voltage: 3.3V/5V
• Connection: PH2.0 terminal wire
• Installation method: double screw fixing

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🖥️ Code Explanation

import machine
import time

pin25 = machine.Pin(25, machine.Pin.IN)    # Tilt switch input
pin26 = machine.Pin(26, machine.Pin.OUT)   # LED output

while True:
    if pin25.value() == 0:                 # If tilted
        pin26.value(1)                     # Turn LED ON
    else:                                  # If upright
        pin26.value(0)                     # Turn LED OFF
        time.sleep_ms(500)                 # Small delay

Step by Step

1. import machine, time → Tools to control pins and add pauses.
2. pin25 = machine.Pin(25, machine.Pin.IN) → Pin 25 reads the tilt switch (input).
3. pin26 = machine.Pin(26, machine.Pin.OUT) → Pin 26 controls the LED (output).
4. while True: → Loop that repeats forever.
5. if pin25.value() == 0: → Checks if the tilt switch is tilted.
6. pin26.value(1) → Turns the LED on when tilted.
7. else: → If not tilted…
8. pin26.value(0) → Turns the LED off.
9. time.sleep_ms(500) → Adds a short delay for stability.

👉 Together, this program makes the LED light up when the sensor is tilted.

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✅ Conclusion of the Test

• If tilting the sensor turns the LED on, and keeping it upright turns the LED off, the program is working correctly.
• This test shows how the robot can sense orientation and react with an output (LED).
• Later, instead of just controlling a light, the tilt switch could be used to stop motors, trigger alarms, or reset the robot if it falls.