Gesture-Controlled Lamp with Arduino and the APDS-9960

A light switch is already convenient, but waving a lamp off while your hands are full is a genuinely nicer trick. This project uses the APDS-9960 gesture sensor — the same family of chip found in older phones’ “swipe over the screen” detection — to recognize four wave directions and control an LED lamp’s brightness over PWM.

How it works

1. The APDS-9960 has four infrared photodiodes in its corners and detects the order in which reflected light changes as your hand passes over it, inferring a direction: UP, DOWN, LEFT, or RIGHT.
2. The Arduino reads gesture events over I2C using the SparkFun_APDS9960 library.
3. UP/DOWN raises or lowers the lamp’s brightness by a fixed step (PWM on the pin driving a MOSFET).
4. LEFT or RIGHT toggles the lamp fully on or off (turning back on restores the last saved brightness).

Parts list

• Arduino Uno/Nano (or any 5V/3.3V board with I2C)
• APDS-9960 gesture sensor breakout (most cheap breakouts already include a 3.3V regulator and level shifting)
• N-channel MOSFET (e.g. IRLZ44N — a low gate threshold that switches reliably straight from an Arduino pin)
• 12V LED strip (or a 12V LED bulb) + a separate 12V supply
• 10kΩ pull-down resistor on the MOSFET gate
• Flyback diode (optional, protects against any inductive load)

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Sample code

#include <Wire.h>
#include <SparkFun_APDS9960.h>

SparkFun_APDS9960 apds = SparkFun_APDS9960();

const int LED_PIN = 9;       // PWM pin wired to the MOSFET gate
const int BRIGHTNESS_STEP = 25;
const int MAX_BRIGHTNESS = 255;

int brightness = 0;
int lastBrightness = 150;    // brightness remembered when turning back on
bool lampOn = false;

void setup() {
  Serial.begin(9600);
  pinMode(LED_PIN, OUTPUT);

  if (apds.init()) {
    Serial.println("APDS-9960 initialized");
  } else {
    Serial.println("Failed to initialize APDS-9960");
  }

  if (apds.enableGestureSensor(true)) {
    Serial.println("Gesture sensor enabled");
  }
}

void applyBrightness() {
  analogWrite(LED_PIN, lampOn ? brightness : 0);
}

void loop() {
  if (apds.isGestureAvailable()) {
    int gesture = apds.readGesture();

    switch (gesture) {
      case DIR_UP:
        if (!lampOn) lampOn = true;
        brightness = min(brightness + BRIGHTNESS_STEP, MAX_BRIGHTNESS);
        lastBrightness = brightness;
        Serial.println("Brightness up");
        break;

      case DIR_DOWN:
        brightness = max(brightness - BRIGHTNESS_STEP, 0);
        lastBrightness = brightness;
        Serial.println("Brightness down");
        break;

      case DIR_LEFT:
      case DIR_RIGHT:
        lampOn = !lampOn;
        if (lampOn && brightness == 0) {
          brightness = lastBrightness > 0 ? lastBrightness : 150;
        }
        Serial.println(lampOn ? "Lamp on" : "Lamp off");
        break;

      default:
        break;
    }

    applyBrightness();
  }
}

The library’s default gesture thresholds can be too twitchy or too sluggish depending on your mounting distance — call apds.setGestureGain(...) or tune GGAIN/GPTHR in the library’s config header if gestures are being missed or misfired repeatedly.

Common pitfalls

• Mounting the sensor near a strong light source (ceiling light, window) floods the APDS-9960 with infrared background noise — mount it somewhere shielded from direct light, or add a small enclosure.
• Undersized or unheatsinked MOSFET when driving a long LED strip — check the MOSFET’s continuous Id rating against the strip’s actual current draw, and add a small heatsink above roughly 2A.
• Skipping the gate pull-down resistor: if the Arduino resets or loses signal, a floating gate can leave the lamp flickering or stuck full-on.
• The APDS-9960’s effective wave range is only about 10-15cm — place it somewhere a hand can reach naturally, like a desk edge or under a nightstand shelf.

Where to go from here

Swap in an ESP32 to publish lamp state over MQTT and integrate with Home Assistant, or use the same chip’s NEAR/FAR proximity gesture to turn the lamp on automatically when someone approaches, without needing a wave at all.