Looking for a (hidden) sensor detecting people on my ground/house entrance

Does anyone have an idea of what device I can use to detect when someone is walking towards my front door? In that case, I would like to turn on the lighting at the edge of the path; a normal motion detector on the door also detects people who don’t want to go to my house. Something like a sensor that registers the step on the pavement.


I use my doorbell camera to do just that

And if lowering sensitivty/range? :control_knobs:

In general various types of motion sensors from pir over radar to mmwave are valid candidates (all need “proper” tuning to fit the use case). :bulb:

Other option would be to use a camera and have a motion (simple) or human (more advanced with frigate) detection :video_camera:

Thank you for your answers. I was hoping there is a sensor I can put at the edge. I do not have a cam at the front. Maybe looking in motion sensor with mmwave or simöar…


Maybe try to explain a little bit more how the area/edge looks like and how you want to install/detect people. :bulb:

Depending on that you might also want to try a (light) barrier type of sensor. A modern ToF sensor for example makes a reflector on the second side obsolete and allows easy installation. :point_down:

Next step obviously would be to count the people :people_holding_hands:

I’ve already thought about that, but the relector bothered me. If there is now a system without this - that could be a good approach. :ok_hand:

Screenshot 2023-10-13 at 10.19.01

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Personally I would suggest a DFRobot based mmWave sensor. Assuming (because of where you posted this Q :wink: ) you are using HA/ESPHome it would be simple and relatively inexpensive and you can point the device directly toward the sidewalk and use the distance setting, which is exceptionally discriminating , I use that word as opposed to accurate because I can’t say for sure if a setting of 2.2 Meters is really that distance but what I can say is that if you stand and move around at the start of your walkway and play with the distance and perhaps sensitivity you can lock it down to practically inches of trigger range where people could be walking by just barely past the setting and it won’t trigger.

Issues you may encounter however with an mmWave is that it’s Milimeter Wave :slight_smile: and it lives up to its namesake, a very small movement can set it off, some mfg and consumer packaged mmWave options claim to remedy this though I can’t speak to that. I’ve definitely heard people say it doesn’t really work the way the mfg says.

I tried, for example, to use one in a small bathroom to turn on the fan-lights when kids, who never do that, walk in to… well you know… and it would turn on the fan-lights on virtually any motion, it was just too small a space and anything from the TP roll end blowing in the AC breeze to the blinds waiving from heat rising up from the vent would trigger it. Depending on your environment it might work great or it may pick up blowing leaves and who knows what critters moving around along the path

It is also worth mentioning that mmWave will work through some solid materials, you could for example put one inside your door perhaps above the door where there is just drywall and outside paneling, or fastened to the inside of a window near the door. The point is, the motion detection is radar not light so it will traverse some materials, thin wood, glass, plastics, not others such as metals, dense objects.

A good example is in my master bath I have an mmwave that picks up human presence even not moving from the other side of a .5 " glass shower surround at an angle.

I use these custom made sensors in my bathrooms which hide and power the mmwave and esp mentioned above but you can literally do anything. Seeed Studios has a human presence kit now that’s just ready to go (in HA/ESPHome) with an mmWave built in and a nice enough case however it does require a USB power nearby.

Hey guys… Thx you all for your ideas and suggestions. I found some projects mmwave sensors.

My favorite is the following solution, which I already run with

  • esp32 d mini
  • DFRobot SEN0395 mmWave radar sensor

Anyone who has a similar requirement will be completely happy. In addition to motion detection, many distance zones can be defined. If you enter the zone the system is triggered.

Have fun.


Hi Sven, how’s your project/experimentation going with the SEN0395 for your pathway monitor? I’ve had a test case where I used the same DFRobot SEN0395 to monitor an outside entry way and I found the false positives to be outrageous. I decided to add a PIR to mine and I’m experimenting with HomeAssistant / Node-RED logic flows so that when, AND ONLY WHEN lol, the PIR is first tripped, then the mmWave is monitored for continuous presence. I actually got the idea from a previous project where I made a mmWave sensor out of a Night Light but then realized it would not be useful to turn lights on… off sure, but mmWave is good at presence detection… not so good at motion (as presence) detection-triggering on the slightest movement of the smallest (hence the name millimeter :wink: ) objects. Whereas the PIR only triggers on larger faster moving things and together you can combine the initial PIR hit with at least a few seconds of ongoing mmWave presence to be sure something is moving down your path, or in your case I wonder if you’ve worked in the zones being triggered in order to signal such an event. Anyway happy to learn of your success or comments. I have a lot of these SEN0395s but only played with the zones on one of them and didn’t have much luck.

So far I’ve only been able to test it in theory because my entrance area is still in the renovation phase. But I’ll be happy to report back when the time comes (At the beginning of next year).

Unfortunately, several zones don’t work properly yet, but we’re still in beta version. If you only operate one zone, the “Target Distance detection” works well in the laboratory and reacts very quickly. This is important for my application because the path lights should be activated one after the other - depending on the position of the person.

Keep you posted.

Oh that actually sounds really cool. I would love to see path lights lighting up based on zone or simply target distances. The one time I tried target tracking it seemed to always be tracking 2-4 targets no matter what was in the room. I recently also tried the newer multiple zones but I could not get the radar module to output “discriminating” zone data… meaning it would trigger multiple zones regardless of the individual zone distance ranges I set, even if they ranges didn’t overlap, even if I left large gaps in the ranges.

I’m currently having the same behavior. Going to report an issue at bit.