Continuous Motion Monitoring?

I’ve been looking for a way to create a motion based system that activates various devices like light switches and appliances by detecting movement in the appropriate room. However, after trying a couple motion sensor options, they all have one flaw that hurts my goal: They detect when motion starts, but don’t continue to monitor motion or notify when motion is no longer detected. My goal is to use the motion detected function to turn everything on, but since some of the devices are lights, I don’t want to just put them on a timer and shut them off if someone is still in the room, so I need a way to continuously check for movement to figure out when everyone has left the room, then set a short timer to turn things off a minute or so after they leave.

Admittedly, I haven’t used anything from the SmartThings family, but I’ve tried things like WeMo and D-Link and found that they were only effective for turning things on, and took so long before looking for motion again that trying to create an effective timer to turn things off shortly after everyone leaves was impossible. I’d like to know if there’s a good device (preferably not AC power dependant, since I’d want the sensors in areas where there’s no outlets) in the SmartThings family, or elsewhere, that can do this. I’m not looking to make a custom solution at this time.

I’m sorry, I’m confused by the basic statement of the problem. There are many motion sensors which will notify after inactivity, and there are many community members using them to control lights. In fact, the number one complaint is usually at the lights turn off too soon because someone is sitting still and the motion sensor reports that there has been inactivity.

Indeed, if you just look at the official smart lighting feature, and you set up a rule to turn lights on because of motion, you’ll see that there is an option there to turn the lights off again after a certain period of inactivity.

I’m not sure about the two brands that you listed, but this does work with most models of motion sensors that work with SmartThings, including The SmartThings brand, gocontrol, Aeotec, Fibaro, Lowes iris, and several more.

So… Maybe you just need a different model? Turning lights off again after inactivity is a pretty basic use case for SmartThings and is supported with both Official smart lights feature and the official routines.

All of that said, I did want to just mention that technically this is not “continuous” motion monitoring, because that would eat up the batteries too quickly. Instead, the motion sensor sleeps most of the time, but it still wakes up quite often, typically either every minute or every three minutes, and checks to see if there is still motion. That’s sufficient for most lighting applications.

Also, I wasn’t quite clear from your post, do you have a smartthings hub? This type of rule would generally require one, it’s not built into the motion sensor itself if that’s what you are asking.

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I appreciate the response.

I currently use services like Android Tasker, IFTTT, and Google Assistant to control much of the Smart Switches and other devices on my network. I bought the D-Link Motion Sensor as it is WiFi based and doesn’t require a hub, as with all the other devices on my network. However, the D-Link Motion Sensor only triggers for motion detected, and only the first time motion is detected (it won’t fire again until motion has stopped for a few minutes). It won’t indicate if motion has stopped, or repeatedly trigger to show that motion is still being detected. It’s good for basic security, to notify if someone entered a room, but doesn’t help with lighting because there’s no way to know if someone is still in the room or not.

It’s good to know that most SmartThings motion sensors are able to report when motion has stopped, and I’m not worried about a minute or so lag, as long as the initial detection of motion is quick. (I don’t want to be walking into a room and have to wait three minutes waving my hands in the air to get a light to turn on, but it’s fine if the lights stay on a few minutes after I’ve left)

I don’t currently have the SmartThings Hub or compatible hub device. I wanted to be sure that SmartThings could do what I was aiming for before investing in it.

To clarify:

A SmartThings compatible motion sensor (as well as other sensors like the Arrival Sensor, Window and Door Sensors) is usually portable and wireless, operating on a CR2032, or CR123 type battery (or similar)
A SmartThings device is usually not able to operate independently with just WiFi and needs a SmartThings or ZigBee/Z-Wave compatible hub to be of any use.
A SmartThings compatible motion sensor will usually be able to trigger a motion detection event instantly (within a second or two), but will not continue to monitor motion and instead sleeps for a few minutes before scanning again to see if there is still motion. When a scan interval passes with no motion detected, the sensor triggers a motion ended event.
SmartThings devices that are able to trigger events can be used in various customizable rules to make these events automatically change the state of another SmartThings device, such as turning a Smart Outlet on or off.
SmartThings rules can also connect to external services, such as receiving events from IFTTT, Amazon Alexa, Google Assistant, and other services, and can also send events to some of these services like IFTTT to make things happen outside of the SmartThings network, such as logging power usage in a Google Sheets spreadsheet using IFTTT.

Please let me know if all of these statements are true, or if I’m wrong with my assumptions. Thanks.

I might be late to this party, but I had a similar problem. In the SmartThings app, when you set a light to turn on based on motion, there is a settings called “turn of after X minutes”. That option works great, but if there is continuous motion it will still turn the light off. That confused me.

However, just yesterday I realized that what I should have been doing was to noty use the “turn light off after x minutes” feature. Instead, I had to create a 2nd automation that said “turn light off if there is no motion for X minutes”.

So to fully automate the motion sensor / light pair, you’d have 2 automations:

  • If motion starts → turn light on
  • If no motion for x minutes → turn light off