Arduino Mega - SW520D Tilt Sensor
This guide shows how to use the Arduino Mega and a SW520D tilt sensor to detect tilt. We will cover the following topics:
- How to hook up a SW520D tilt sensor to an Arduino Mega
- How to write a program for Arduino Mega to detect tilt with a SW520D tilt sensor
Later, you can change the code to turn on an LED or a light (using a relay) when it detects tilt, or even make a servo motor move.
Hardware Preparation
Or you can buy the following kits:
| 1 | × | DIYables Sensor Kit (18 sensors/displays) |
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Additionally, some of these links are for products from our own brand, DIYables .
Additionally, some of these links are for products from our own brand, DIYables .
Overview of SW520D Tilt Sensor
You can use a SW520D tilt sensor to detect when something is tilted or moved. Inside the module, there is a small metal ball that rolls between two electrical contacts depending on the angle. The module gives a simple ON or OFF digital signal.
The SW520D Tilt Sensor Pinout
The SW520D tilt sensor has three pins.
- VCC pin: connect to power (3.3V to 5V).
- GND pin: connect to ground (0V).
- DO pin: this is an output pin. It goes HIGH when the sensor is upright and goes LOW when it is tilted. Connect this pin to an input pin on the Arduino Mega.
image source: diyables.io
The SW520D tilt sensor module also has two LED lights.
- One LED light for power
- One LED light for tilt state: on when the sensor is upright, off when it is tilted
How It Works
- When the sensor is upright, the metal ball closes the contact, and the output pin goes HIGH.
- When the sensor is tilted, the metal ball opens the contact, and the output pin goes LOW.
Wiring Diagram
This image is created using Fritzing. Click to enlarge image
How To Program For SW520D Tilt Sensor
- Sets a pin on the Arduino Mega as a digital input using the pinMode() function. For example, pin 8.
pinMode(8, INPUT);
- Uses the digitalRead() function to see a pin's state on the Arduino Mega.
int tiltState = digitalRead(8);
Arduino Mega Code - Detecting the tilt
/*
* This Arduino Mega code was developed by newbiely.com
*
* This Arduino Mega code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/arduino-mega/arduino-mega-sw520d-tilt-sensor
*/
#define SENSOR_PIN 8 // The Arduino Mega pin connected to the DO pin of the SW520D tilt sensor
int prev_tilt_state = HIGH; // the previous state from the input pin
int tilt_state; // the current reading from the input pin
void setup() {
// initialize serial communication at 9600 bits per second:
Serial.begin(9600);
// initialize the Arduino's pin as an input
pinMode(SENSOR_PIN, INPUT);
}
void loop() {
// read the state of the input pin:
tilt_state = digitalRead(SENSOR_PIN);
if (prev_tilt_state == HIGH && tilt_state == LOW)
Serial.println("The tilt has been detected");
else if (prev_tilt_state == LOW && tilt_state == HIGH)
Serial.println("The tilt has disappeared");
// save the the last state
prev_tilt_state = tilt_state;
}
Detailed Instructions
Do these steps one by one.
- Connect the SW520D tilt sensor to the Arduino Mega following the diagram.
- Connect the Arduino Mega to your computer with a USB cable.
- Open the Arduino IDE on your computer.
- Select the correct board: Arduino Mega, and the right COM port.
- Copy the code and open it in the Arduino IDE.
- Click Upload to send the code to the Arduino Mega.
- Tilt the SW520D sensor back and forth.
- Check the results in the Serial Monitor.
8
Serial.println("Hello World!");
Message (Enter to send message to 'Arduino Mega Or...' on 'COM15')
New Line
9600 baud
The tilt has been detected
The tilt has disappeared
The tilt has been detected
The tilt has disappeared
Troubleshooting
If the SW520D tilt sensor isn't working well, try these steps:
- Check the orientation: The SW520D is sensitive to its mounting angle. Make sure it is installed in the correct upright position for reliable detection.
- Reduce vibrations: The tilt sensor can also react to mechanical vibrations. Fix it firmly to a stable surface to reduce false triggers.
- Check the wiring: Make sure the VCC, GND, and DO pins are connected correctly.
- Check the power supply: Make sure the power supply is stable for consistent readings.