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  • Really cool idea, and scratches an itch I have with current motion detection sensors (looking at you LD2410...)

    What's the configuration/calibration like? Do I need to set any proximity baselines?

    by tetris11
  • No calibration is needed for the motion sensing. You can adjust sensitivity in the dashboard if you get false positives though.

    In the future, when I add stationary presence detection, there is a good chance a small calibration will be needed.

    by mike2872
  • Super cool! I'm going to try this out!

    The new philips hue bulb bridge supposedly can turn them all into motion sensors. Do you think this could use what ever data they are pulling from the bulbs to do that as well?

    by worldmerge
  • Unfortunately not. Even though the concept is the same, Philips Hue uses Zigbee as the sensing protocol which isn't compatible with the Wi-Fi sensing TOMMY uses.
    by mike2872
  • This seems really cool, but unfortunately I can't get it to work. The flasher says it can't open the serial port for most of my ESP32s, and the one that does work goes into a bootloop after I enter the wifi credentials.
    by stavros
  • Could you open a support thread in the Discord channel? Some boards have some quicks to them. But it's all been solved by other users before. I'm sure there's a solution to your board too.
    by mike2872
  • Could this work without touching my WiFi? For example, an ESP node with ethernet to communicate with Home Assistant, while using it's own WiFi mesh network for detection and/or to talk to other nodes. Or, is the connectivity to my home WiFi network a requirement?
    by atmanactive
  • Right now it is a requirement that the device running TOMMY (e.g. Home Assistant) and the ESP32 nodes are on the same network. The communication between the ESP32's are peer-to-peer without needing the router, but the data needed for analysis is sent from the sensors to TOMMY through the router.
    by mike2872
  • Without having the time right now to dig too deep, I have a few questions:

    1. Does it have any idea of the range at which motion is happening, relative to the distance between nodes or otherwise?

    2. Can it correlate motion with that of another WiFi or Bluetooth device? So if I'm carrying my phone and it can see me moving, can it tell that it's me?

    3. What's the movement -> signal latency?

    by regularfry
  • Thanks for the questions.

    1. As of now it only knows whether there is motion in the zone or not. Actual (x,y) coordinates within the zone are theoretically possible and something I have on the roadmap for 2026.

    2. No, it doesn't correlate with other devices currently. But Wi-Fi sensing can theoretically identify who is moving by analyzing how you disrupt the signal. We all have unique movement patterns. I actually have a working proof of concept that can differentiate between me and my girlfriend, but it's very experimental and not stable enough for release yet. Definitely on the future roadmap though.

    3. Pretty much instant (around 50ms). The detection happens in real-time as the signal disruption is analyzed.

    by mike2872
  • What dark magic is this! Very cool repurposing of technology. If you don't mind me asking - what's the origin of the name Tommy?
    by dreadsword
  • Thanks! Glad you like it.

    Honestly, it doesn't stand for anything! A couple years ago I was playing around with the concept and a song came on that mentioned "Tommy" repeatedly. I jokingly started calling it Tommy when talking to my girlfriend about it.

    So every time the lights turned on or off it was "Tommy who did it" and the name just stuck. Now I'm too invested to change it.

    There's a dedicated thread on the Discord channel where people are coming up with good ideas for what TOMMY stands for. Some of the suggestions are "Totally Overengineered Motion Monitoring" and "Through-Obstacle Motion Monitoring". People are still working on what the Y should stand for.

    by mike2872
  • Could you help me understand the use case for this? I've used PIR and mmWave before. When would you choose tommysense vs some other option.
    by kentt
  • What really sets TOMMY apart is that it doesn't require line of sight and works through walls. This opens a lot of possibilities.

    You can create zones spanning multiple rooms without sensors in each room. Instead of traditional room-by-room motion detection, you could divide your house into zones like "upstairs", "downstairs", or "living area". Especially useful for controlling heating by floor or area-level lighting.

    Working through walls also means less clutter. You can hide devices in drawers, closets, or anywhere out of sight.

    There's also a pricing aspect: ESP32s can be acquired for a couple of dollars each, so you could have motion sensing throughout your whole house for a fraction of the price of dedicated sensors in every room.

    by mike2872
  • Congrats, this looks like an awesome product! Gonna try setting it up in the next few weeks.

    How is a "zone" configured? I understand that if I have 3+ devices, the zone is essentially the area between them. But what about two devices? I'm assuming the zone isn't just a straight line between them, or maybe it is? What kind of zone configuration can one do in the dashboard?

    by yoavm
  • Thanks, I'm glad you like it! Let me know how it works for you. And if you need any help, feel free to reach out.

    A zone is 2 or more devices. So 2 works just fine. Instead of a straight line, image two flashlights pointing at each other. The beam of the flashlight becomes the sensing area.

    In the dashboard you can create zones which you put devices into. So you could flash a handful of devices and put them into a "living room" or "upstairs" zone.

    by mike2872
  • Congrats on the launch, that looks really cool!

    I had an idea to build a restricted zones for a phone. For example, I can't take my phone to bed, so I wanted to create a esp32 based project that beeps when the phone is too close to some areas. I made it based on BLE, but iphone masks MAC addresses, so it was impossible to track particular devices. No I realize, I could actually do it with WIFI signal straight. How I didn't think about it. Will try again today :D

    by cassettelabs
  • Thanks! I'm glad you like it.

    Sounds like a great project. Using the Wi-Fi signal directly might work in your case. It would be nice to go back to actually using the bedroom as a place to sleep and not look at the phones all the time :-)

    by mike2872
  • Seems to be based on See through walls by MIT (2013)? Good job porting it to esp32. I was just looking a week ago to do the same thing - basically reproducing this work. I'll definitely try this. https://www.media.mit.edu/projects/seeing-through-walls-comp...
    by shekhar101
  • I believe that was the initial paper which really started the Wi-Fi sensing research. Although a lot of research has come after that. It's a really fascinating technology with a whole range of possibilities beyond just motion and presence sensing.
    by mike2872
  • "ESP32 CSI Toolkit", papers+code, Virginia Commonwealth University, USA https://stevenmhernandez.github.io/ESP32-CSI-Tool/

    "Wi-ESP", papers+code, KITS WRL, South Korea, https://wrlab.github.io/Wi-ESP/

    "Espressif CSI sample applications", Shanghai, China, https://github.com/espressif/esp-csi

    "CSI-MURDER", paper+code, WiFi Sensing countermeasures, EU, https://ans.unibs.it/projects/csi-murder/

    by transpute
  • This is impressive and some of the "coming soon" features are ambitious. So, these devices mesh with each other. Are they like "idle" WiFi connections, or are they chatty? I'm wondering how much spectrum clashing there will be. WiFi can be finicky enough as-is.
    by throitallaway
  • They send packets to and from each other in a mesh network. It's quite small packets and not a large amount of packets a second. For a standard use case (3-4 zones) the interference is quite low on 2.4Ghz, and almost negligible on either 2.4Ghz (Wi-Fi 6, like the ESP32-C6) or 5Ghz (ESP32-C5).
    by mike2872
  • > No hub required - TOMMY runs as a Home Assistant add-on or on a Linux host (Docker) and uses supporting devices to create a sensing network.

    I don't see how either the HA instance or the Linux host can't be viewed as a hub. No hub required feels untrue to me. I assume this question is intended to clarify that some additional device is not necessary, but I think this could be reworded.

    by michaelmior
  • You are of course correct but in the HA community "no hub required" often should be read as "no addiditonal hub required because HA can communicate directly with it"
    by victorbjorklund
  • OTOH, when you buy any Bosch, IKEA, Hue, Aqara device, it says on the box: Hub required (and they do mean get our hub and place next to all other hubs. Even though Home Assistant will usually work fine-ok).

    So I see where he’s coming from, and I interpreted it as intended.

    by teekert
  • Fair criticism. I think the generous interpretation of "no hub" means you don't have to buy a specialized hub eg a Smartthings hub.
    by kentt
  • You're absolutely right. Thanks for the feedback! "No hub required" is misleading. What I meant was "no additional proprietary hub". Meaning, if you're already running Home Assistant or have a Linux machine, you don't need to own a separate device like Zigbee/Z-Wave hub. But yes, the HA instance or Linux host is effectively acting as the hub. I'll update that wording on the site.
    by mike2872