Below is a schematic floor plan of my kitchen and adjacent dining room. There is no door between them. I’d like to detect when there’s someone in the kitchen, so I can turn on the light. However, I don’t want the light to turn on every time someone walks in the dining room near the kitchen.
Are mmWave presence sensors accurate enough to do this? I was thinking of placing one in the corner on top of a cupboard. (Where the red dot is in the floor plan.) Could a mmWave sensor detect someone as soon as they cross the dotted line, but not as long as they stay on the dining room side of the dotted line?
If so, do people have recommendations for specific sensors? I want it to be reliable of course, but I don’t want to spent too much money on it. I have s Zigbee network, but a WiFi solution is also fine with me.
If mmWave is not an option, any suggestions for alternative solutions?
I am using a Aqara FP2 sensor for “uhm?” 2 years now and can confirm that this sensor will work in your situation because I have a simulair setup/floorplan
Your sensor is facing the dining room, which you want to exclude. Is there any way to place it on the boundary between the kitchen and the dining room, facing the kitchen?
I’ve updated the drawing: the orange/yellow box is a cupboard that’s ~ 2 meters tall. I think you’re suggesting to put it where the green dot is, right? Could be a solution, but (based on my experience with PIR sensors) I’d be a bit concerned that it would detect presence too late.
I have a similiar setup with my kitchen and dinning room and living room. I have been using the Everything Presence One sensors (Everything Presence One – Everything Smart Technology) for the past year in each room and the PIR sensor has been fast enough to trigger upon someone entering and the mmwave sensor has been able to be set to different rooms so you have not only fast response but also good presence detection and a few other features such as temp and humidity and light level. The detection is good enough I was able to get it to reliably trigger within 1 second or so of crossing the threshold for each room, just takes a little bit of trial and error setting up the ranges and sensitivity and angles. They were really easy to setup and get zero’d in for the areas I have them and since you run them on standard wifi there’s no need for a hub. They are my goto presence sensors now and I’m going to try out the Everything Presence Lite (Everything Presence Lite – Everything Smart Technology) sensors next for their zone and multi-target tracking features.
I think you’ll find mmWave sensor fairly quick in detecting presence.
I have a LD2450 based sensor in my office and it is programmed to turn on my light when I enter the room - not if I stand just outside the door or even the door opening for that matter.
I use the exclusion zone to avoid turning on the light when my 3D printer in my office is running (Bowden tube stick out and moves).
I would suggest that you put the sensor on the end wall in your kitchen because detection zones and exclusion zones are (at least in the case of LD2450) defined as rectangular areas parallel to the sensor.
In both your proposed placements you’ll have difficulties defining precise inclusion and exclusion zones that fits your purpose.
Presence sensors, based on mmWave radar are sensitive. Most of them have also sensitivity level adjustments. So you could control the distance where (not) to detect the presence.
I tried many of them, from cheap DIY modules to expensive ready products. ZWave and Zigbee presence sensors make no sense because the radar method of detection is (relatively) hungry to power (5-50mA constantly) versus 5-50uA of the uController sleep. Therefore, presence sensors are usually powered from USB or from mains. Just a topic to keep in mind.
And the last: presence sensors “sense” also on their “back”. If behind your kitchen there is another room or apartment or street, it will capture the presence of people also there. The solution for that is Faraday screens but its bulky and ugly.
I currently use a few of these for my motion detection needs without issues:
The one for my kitchen is mounted in the corner of the window and doorway wall and only triggers when I enter the kitchen since its facing to the opposite corner diagonally into the kitchen and with a slight angle down.
The battery on them is only just hitting 80-90% after a full year of usage.
Someone else has already mentioned the FP2, which is a very capable device and very configurable - I have several and like them.
I also have a couple of these DFRobot 0610 sensors that I use with ESP32 modules all packed away in small project boxes and I find them quite capable and much cheaper to deploy. While not graphically configurable it’s easy enough to set the distance to which they sense occupancy so that would be a fairly inexpensive way to go.
But isn’t that PIR sensor? I’d go for mmwave for sure, PIR feels like old tech compared to mmwave.
I’m mostly using the cheap Wenzhi senors myself, they’re pretty good although they do give me a ghost reading every now and then. But they rarely miss presence, in fact I’m using them to switch off air conditioners after a few minutes of no presence and they’ve never switched them off while I was still there. They might miss a human presence for a few seconds though but not for much longer.
Keep in mind that Wenzhi sensors spam a lot so I’d strongly advise to patch them, so you do need to be a bit technical.
I also own the Aqara FP2 sensor and honestly I don’t find it to be any better, maybe even worse in my opinion, although you can configure them more.
The great thing about the Wenzhi sensors is that they have a ceiling mounted version. It’s really beyond me why other brands aren’t offering these.
Perhaps a fault in the forum software but I can’t tell if you’re responding to me or someone else. No, the DFRobot 06xx sensors are absolutely mmWave sensors (and quite accurate to boot).
Yes they are your bog standard sensor type but they do work fine, I got them before mmwave started coming out for HA.
I have 3 of them atm, one for the kitchen, one setup in the bedroom at the base of the door angled slightly down to avoid false positives when I am in bed until the bed occupancy automation disables motion light control and one facing the door into the bathroom from the other side of the wall to keep my led strip on when I don’t need to use the light tied to the exhaust fan via a wasp in a box setup.
Overall I have yet to have any ghost activation’s in my setup.
It’s too bad those producers rarely provide the type of sensor chip they’re using. Since pretty much all of the important processing happens inside there, I don’t expect much differences between 2 different sensors using the same chip.
It seems quite a few sensors use the ICLEGEND S3KM111L chip. That same company also released some other chips like ICL1122. And then some sensors use the Phosense’s XBR818 chip. It would actually be interesting to see some comparions between different chip performances. But like I said, unfortunately info on which chip they use is very scarce.
I own 3 different Wenzhi sensors, they all use the S3KM111L chip.
I use the HLK-LD2410C and they work very well, detection adjustable for distance and sensitivity with an app via bluetooth.
they don’t detect from behind.
Ammm… not entirely true. Mine does, just not as far as from front.
I guess it depends on where it’s installed. I have it hanging from a ceiling in a box and since it’s open (no wall) from front and from back it does detect from behind. From a shorter distance, but it does. So to prevent this i guess some sort of metal screen would be needed if sensor is not installed on a wall behind it.
ok, I use 4 of them, they’re all mounted against or in a wall, none hanging from the ceiling tho, that must be why yours is detecting from behind, good to know!
I did some testing back then with one (before buying more) to be sure they don’t detect through a wall.
I’m a bit confused, this is a ‘module’, any idea what chip it uses? And how do you even use such module, I guess you use the UART as input for an ESP32? And does the manufacturer provide sample code? Or is that available?
