Washing machine makes mmwave sensor indicate motion as active

I purchased some of those Linptech mmwave sensors and installed one in my laundry area opposite to the laundry machine. I am using the amazing Tuya multisensor 4 in 1 device driver.

I have noticed that with the sensitivity for motion and static detection set at the default 5, while the washing machine is running a cycle, the sensor reports motion as active even when no human is in the area. (the washing machine is a front loader if anyone's curious)

Screenshot 2023-10-27 at 9.26.28 PM

Reducing the 'Static Detection Sensitivity to 4' makes it show motion as inactive when I sat there motionless for a while. Which I feel defeats the purpose of the sensor.

Has anyone else run across a similar situation? What placement strategies did you employ?

No, but using mmW to indicate the washing machine is running is a great idea I had not considered. Not something I would personally need, but some of the very efficient washing machines are difficult to sense running state based on power measurements alone. I ended up installing a running light sensor on my old 220v Bosch for the best results.

A mmW sensor is a much less expensive option though. :+1:t2:


I think that the only stable solution would be to mount the device on another wall, so that the vibrating washing machine is not in the sensor view.

You could also experiment to dynamically change the sensitivity parameters of the sensor using the Rule Machine custom actions ( SetPar ).
Click on the SetPar button to see the list of the possible parameters in n the live logs page.

So, if you know that the washing machine is running (from a power metering plug as example) - reduce the static sensitivity to 4.
If the power consumption is less than a certain threshold wattage for more than a few minutes- rise the sensitivity to 5.

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Some things are just easier with an old school PIR motion sensor and a 1 minute motion timeout. A person should have moved enough for PIR detectors within a minute in a room where most tasks are short and require constant motion.

But for mmwave sensors, small motions like the vibrating of a washing machine is exactly the type of thing these sensors were designed to detect. I had to figure out new placement options in my carport where wind blowing the plants, even just barely, was setting off motion alerts falsely.


Yes, the mmWave sensors can not distinguish between a human/animal movement and any other object movement. PIR sensors are triggered by the change of the infrared radiation of the human/animal bodies, so they are better in some use cases.

Indeed, I have a mmWave sensor (in breadboard form). The "presence" function senses a human breathing movement. Definitely makes one think.

As @a.mcdear pointed out, is this something you’re likely to do in your laundry room on an everyday basis?

mmWave sensors can be very useful in situations that PIR sensors don’t do well in. But I agree that PIR sensors still have a role for motion sensing in some areas of most people’s homes.

Interesting. My Linptech is directly facing washer/dryer combo unit and it is 3-4 ft away. It doesn't detect any washer activity but very reliably detects humans.

I did not know I could use rule machine to change the sensitivity parameters. Thanks for the tip!

Yeah I’m not very likely to stay still in front of the laundry machines often. But this is just an edge case I came across as I’m experimenting with the mmWave sensors and happened to be standing there inspecting the tub clean cycle of the machine.

How interesting. Is yours a front loading washer? I wonder if water movement is detectable through the clear plastic door of a front loader and not through the metal sides of a top loading washing machine.

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Could you block the mm wave from going in a direction? I was able to desensitize my test unit with a plate of 0.062" aluminum plate. This was what I had, I don't know what other material/ thickness will do the same.

Yes, it is compact LG front loader washer/dryer combo unit.
At a high speed spin the vibration is significant.