Live data from Hacker News

Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors

tommysense.com

1–10 of 84 posts

Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors

#1
Hi HN! I would like to present my project called TOMMY, which turns ESP32 devices into motion sensors that work through walls and obstacles using Wi-Fi sensing.

TOMMY started as a project for my own use. I was frustrated with motion sensors that didn't detect stationary presence and left dead zones everywhere. Presence sensors existed but were expensive and needed one per room. I explored echo localization first, but microphones listening 24/7 felt too creepy. Then I discovered Wi-Fi sensing - a huge research topic but nothing production-ready yet. It ticked all the boxes: could theoretically detect stationary presence through breathing/micromovements and worked through walls and furniture so devices could be hidden away.

Two years and dozens of research papers later, TOMMY has evolved into software I'm honestly quite proud of. Although it doesn't have stationary presence detection yet (coming Q1 2026) it detects motion really well. It works as a Home Assistant Add-on or Docker container, supports a range of ESP32 devices, and can be flashed through the built-in tool or used alongside existing ESPHome setups.

I released the first version a couple of months ago on Home Assistant's subreddit and got a lot of interest and positive feedback. More than 200 people joined the Discord community and almost 2,000 downloaded it.

Right now TOMMY is in beta, which is completely free for everyone to use. I'm also offering free lifetime licenses to every beta user who joins the Discord channel.

You can read more about the project on https://www.tommysense.com. Please join the Discord channel if you are interested in the project.

A note on open source: There's been a lot of interest in having TOMMY as an open source project, which I fully understand. I'm reluctant to open source before reaching sustainability, as I'd love to work on this full time. However, privacy is verifiable - it's 100% local with no data collection (easily confirmed via packet sniffing or network isolation). Happy to help anyone verify this.

Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors
tommysense.com

Re: Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors

#3
> 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.

Re: Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors

#4

> 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.

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.

Re: Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors

#5

> 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.

Fair criticism. I think the generous interpretation of "no hub" means you don't have to buy a specialized hub eg a Smartthings hub.

Re: Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors

#7
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.

Re: Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors

#8
post #4

> 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.

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.

I figured that's what you meant and I think it's totally reasonable! I just think the wording could be updated a little. I have a couple ESP32s lying around not doing anything, so I'm looking forward to trying out TOMMY with HA :)

Re: Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors

#9
post #4

Earlier quoted context omitted.

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.

I figured that's what you meant and I think it's totally reasonable! I just think the wording could be updated a little. I have a couple ESP32s lying around not doing anything, so I'm looking forward to trying out TOMMY with HA :)

I agree. I'm going to find something more suitable :-) Sounds good. Looking forward to hearing about your results!
Post reply on HN