Mijia smart light-sensing night light with human sensor

1. Project Introduction
Currently, the most common sensor in Mijia is the human infrared sensor. The human presence sensor is currently led by Lingpu and Ziqing, and Mijia headquarters has not taken any action.
Since Xiaomi IOT does not provide chips for sale to individual developers, there are also many human presence sensors, door and window sensors, etc. modified on the Internet. The basic functions are similar. The price is indeed not optimistic. (I can't afford it)
After my wonderful ideas and inspiration from the big guys' plans. I came up with the idea of ​​using Mijia's newly launched Mijia smart light-sensing night light to transform the human presence sensor. The price is cheap and the function is moderate. Only 30-50 yuan is enough.
This plan is partly inspired by Xianyu @狗东的谍, Station B @沈乔治_
 
生病, QQ Exchange Group: 713228544
2. Description
This project is divided into a deluxe version and a regular
 
version. The deluxe version uses an advanced ACDC power module, and arranges peripheral safety measures and filtering to ensure that the power supply is more stable and safe.
 
The regular version uses the most basic components to ensure that the circuit can operate normally.
 
Control principle:
The initial solution was to use radar to control an LED to illuminate a photoresistor to achieve switching, but the heat was serious and the LED might be damaged during use.
So the solution was improved and implemented through optocouplers.
 
The night light could originally be linked to other devices through the luminous flux of the photoresistor, but now it can be linked by changing the photoresistor to an optocoupler. When the radar detects someone, it outputs a high level and gives a signal to the optocoupler to turn on the light. When the radar detects no one, it outputs a low level and turns off the light.
3. Component preparation
Ordinary version
1. Mijia Smart Light Sensing Night Light MESH
2. LD2410B radar, choose Bluetooth version
3. EL357N optocoupler
4. ACDC power module 5.
1K resistor * 1, 0603LED * 1, cable tie * 2 electrical tape, 4 M2 * 5 screws
 
 
Deluxe version (added on the basis of the above)
1. ACDC replaced with HLK-PM01
2. 100NF safety capacitor K104K275VC3L3.5
3. Varistor 10D561K
4. Disposable fuse SET T2.5A 250V
5.100UF capacitor
6.Common mode inductor
4.The magic modification
involves 220V strong electricity, please pay attention to the safety of electricity.Both
 
the adapter board and the 3D shell can be printed for free.Drill
 
the adapter board with 1.2mm.Weld
 
 
the radar, resistor and LED to the back of the adapter board.Weld
 
the power module and optocoupler to the front of the adapter board, and
fix the power module with cable ties or tape.Fix the adapter board to the 3D shell.Remove
the night light shell, remove the night light photoresistor, and remove the touch spring.Connect
the power module through the 220V pin of the night light, and the photoresistor pin to the optocoupler {the photoresistor is connected to the optocoupler + on the left and the photoresistor is connected to the optocoupler - on the right}.Isolate
the 220V power pin and the night light PCB with electrical tape to avoid contact short circuit.The
assembly is completed by installing the shell (the shell in my hand is larger, and the size is normal in the project now)
4.Testing
 
Since the night light reset is not brought out, the night light reset method is still the original long press spring reset. The spring is not used with tweezers. Long press the original spring contact
 
to download HLKRadarTool https://www.pgyer.com/Lq8p
IOS can be searched and downloaded in the store.
 
 
Mijia settings turn off the light sensor to automatically turn on the light, and the automatic scene settings are
ambient light-on XX
ambient light dark-off XX.
Plug the modified night light into the socket, and after powering on, open the APP and it will automatically search for radar signals. Enter the password to log in.
 
The red circle represents someone, the pink circle represents stillness, and the green circle represents no one.
 
The red line represents the set threshold and the blue line represents the energy value of the object. When the energy value of the object is higher than the threshold, the light
 
turns on when someone is detected. The LED turns on, and when no one is detected, the LED turns off
. Adjust the parameters according to the test of human entities entering and exiting the space. Specific adjustments are made for specific spaces.
No adjustment instructions are given here. Sensitivity 0 is the most sensitive, 100 is the least sensitive
4. Video
tutorial on B station: https://www.bilibili.com/video/BV1GR4y1y7Mn/?vd_source=74a9f6cb9a59140477fef67bbb0ec8ee
At present, mine is not fully adjusted, and there is a delay when turning on the light