I just wanted to share a project before I ordered the parts SLS printed in PA12 nylon just in case I forgot something crucial.
I was not happy with most of the mmwave sensor housings available to Print., They were too large, too pointy on the corners, limited mount options, and none had a provision for ceiling fan shields.
So I whipped up something in CAD.
This combines a panasonic EKM[BC] low profile PIR sensor, a Hi-Link LD2410C mmWave radar, and a combo AHT20/BMP280 temperature/humidity sensor all in one. Power is provided by USB, and the mount holes (3 options) are threaded for 1/4"-20 threads (to utilize CCTV mounts, ball gimbals, etc).
Features:
Size: 80mm long x 37mm wide x 24.6mm deep.
Sports a full-size 38-pin ESP32 so you can have BT proxy and wifi all in one device.
Venting. Lots of venting. Not just venting but directional venting.
Two positions to install the LD2410C depending on if you have a ceiling fan or not.
Optional push-in ceiling fan shield to stop the fan from keeping your triggers on. (only works in one of the two LD2410 positions)
1/4" - 20 thread mounts in 3 equally spaced positions to utilize common camera and cctv mounting options.
Screwless design (mount aside).
No large overhangs or other gotchas for traditional FDM 3D printing.
What would you change? And before anybody says POE, an Olimex board isn’t fitting in that footprint. I originally designed it for a D1 mini but… BT proxy and more cheap chinese smarthome stuff using BT these days. Figured it would be best to try and maximize the available sensor networks.
Now… a remix of the popular esp32 smart vents but without MQTT and WITH POE power and esphome? That might be a next project. I feel like it should be possible to network a bunch of pressure sensors through the ductwork to get a good balanced airflow and eliminate the need for the smart vent aspect entirely. A lot more cost effective too.
AH, I have not released it yet. I wanted to wait to see if somebody said “But what about ____” and if it seemed like an obvious (to me) deficiency then I’d update the design. I also haven’t had these printed yet. The tolerances might be a little tight. I have only left .13mm between sliding parts, .05mm for PCB holes (those should be pretty precise though) and the panasonic pir is a 0mm clearance pressure fit.
Ah, and I just realized I need to cut the relief for the USB plug. But if you have a prusa / voron / bambu lab / resin printer / seckit / rat rig v core or basically anything known to hold .15mm or better tolerance I would be super happy to send you some .stl’s for testing as long as you promise to send photos and let me know how things fit!
All three of my printers are down (neglected) and having a pro shop print in nylon12 on an MJF/SLS is not exactly budget friendly for prototyping.
Looks very nice. Have you found a volunteer to print your prototype yet? If not feel free to message me.
BTW, why did BLE require going to a large form ESP32 board? The esp32 version of the D1 mini has BT/BLE - I use them for simple BT proxies all over my house.
True - but the “D1 mini esp32” is an esp32 device in a similar form factor (a slight bit wider to accommodate a second row of pins). It supports BT/BLE perfectly.
I avoided the double wide because in the typical living space I find narrower enclosures much easier to make blend with the rest of the home. I primarily designed this to go where people usually stick things like the Aqara sensors (corners near ceilings).
I do not want to version on gdrive, so here’s a printables link. Imade a few tweaks for ease pf print and ease of installing the climate pcb.
