Motion Detector

Working with a Motion Detector 2.0 sensor or Motion Detector 1.0 sensor works as described in the general article on how to use sensors. In this article, we assume you have successfully initialized the devices with the Tinkerforge Device Manager, and you stored all connected devices on a global variable devices. We also declared a global variable called motionDetector.

The following tutorial works for both motion detectors 1.0 and 2.0. The only thing that is different is the device identifier.

Next, we need to know the device identifier, which 292 (Motion Detector 2.0) or 233 (Motion Detector 1.0):

// Get the motion detector sensor via its device identifer
motionDetector = devices.getDeviceByIdentifier(292);

Once we have a reference to the sensor, we can register a callback function:

// We want to be informed when a new sensor value arrives
motionDetector.registerListener(motionDetected);

Of course, we have to actually define the function:

function motionDetected(val) {
   // Do something with the value object
}

Detecting a motion

In the callback function motionDetected(), we can access the information about the event via the val parameter:

function motionDetected(val) {
    var motion = val.getValue();
    
    if(motion.type === "motion_detected") {
        log("Motion detected");    
    }
    else if(motion.type === "detection_cycle_ended") {
        log("Ready to detect another motion");
    }
}

The motion detector sends to types of events:

1. One type motion_detected, when the sensor detects a new motion.

2. Following a few seconds after a motion was detected, we get an event detection_cycle_ended, that signals that the sensor is now ready to detect another motion.