This is a human detector which uses HmmD Mmwave Sensor to detect humans.
I wanted to create a human detector using the Mmwave Sensor to detect humans and alert me when human is detected cuz some people always steals the flowers in my garden, and I want to catch them in the act.
Believe it or not, this was my second time using Fusion 360 and KiCad! I watched numerous tutorials and guides and did a kg of googling, but in the end, I'm pretty proud of the final product. I had the most struggle figuring out how to make sketches, and with the new mouse controls, it definitely took me a while to get the hang of it. Also in KiCad, I had a lot of trouble with footprints and making sure everything was aligned properly and the traces were correct(but it became a litle long traces).
- STEP 1: Buy all the things listed in the BOM, a 0.1µf decoupling capacitor(ceramic & and not mentioned in BOM) & print the case for the sensor and also order the PCB(PCB/motionalr_mcu.zip).
- STEP 2: Solder the 0.1µf decoupling capacitor to the HMMD mmWave Sensor. One leg of it to VCC and another leg to GND.
- STEP 3: Assemble the PCB.
- STEP 4: Flash MicroPython to the XIAO and place the main.py in the XIAO.
- STEP 5: Connect the PCB to the sensor using a LAN Cable(less than 3m) or any twisted Pair Cable(Use the following table as reference).
| Twisted Pair | Use For |
|---|---|
| Pair 1 | 3.3V + GND |
| Pair 2 | TX + GND |
| Pair 3 | RX + GND |
| Pair 4 | OT2 + GND |
- STEP 6: Put the sensor in the case and put it outside or where you want it to be placed.(You may put it near your bedroom so that it alerts you when someone is coming or near your fridge if you have siblings.)
- STEP 7: Put the PCB inside your house while connected to the sensor using a lan cable(length must be less than 3m).
- STEP 8: Power the XIAO using a USB-C Cable.
- STEP 9: Sleep peacefully or If you want to test go near it and see how it screams.
- STEP 10: Do Anything With It. Thank You! Also Please give a star to this poor fellow if you like the project. Thank You Again!
BOM:
- 1x Seeed Studio XIAO ESP32-C3 development board
- 1x Waveshare HMMD 24 GHz mmWave human presence sensor
- 1x Passive piezo buzzer, 3 V, Ø12 mm
- 1x NPN transistor 2N2222, TO-92 package
- 1x Resistor 10 kΩ, ¼ W, through-hole
- 1x Resistor 1 kΩ, ¼ W, through-hole
- 1x Resistor 100–200 Ω, ¼ W, through-hole
- 1x Resistor 22–33 Ω, through-hole
- 1x Signal diode 1N4148
- 2x 0 Ω SMD resistor
- 1x 5-pin connector / header for HMMD sensor - Male
- 1x 5-pin connector / header for HMMD sensor - Female
- 1x LAN / multi-core cable for sensor connection
- 4x M3x16mm Screws
- 4x M3x4mm Heatset Inserts
- 1x PCB
Others:
- Micropython Firmware
- PCB Gerber File(PCB/motionalr_mcu.zip)
- Top and Bottom of Sensor Case STL files for 3d Printing
- BOM.csv
| Schematic | PCB | Sensor Case (Top) | Sensor Case (Bottom) |
|---|---|---|---|
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The code is still basic in functionality because of lack of information on the sensor datasheet, but I will update it as soon as I get the sensor and debug it's output. The case for the mmwave sensor is measured with approx measurement available online, so I will also update the case design once I get the sensor and measure it myself. The PCB will be left bare as I like looking at PCBs.