Story
There is a huge wastage of energy in our daily life, which can be saved if we turn off the devices when not in use. Unfortunately we humans are so busy that we forget to turn them off. So to solve this problem, we thought of making all the electrical components smart. Initially, we started with making our work desk smart. For this, we placed an IR sensor on the desk which will detect if anyone is sitting on the desk, and toggle its output. The IR sensor is connected to a microcontroller which controls the Relays based on the output of the IR sensor.
Components
IR SensorIR sensor is an electronic device that emits light in order to sense some object in the surroundings. An IR sensor can measure the heat of an object as well as to detect motion. Usually, in the infrared spectrum, all the objects radiate some form of thermal radiation.
4ch RelaysA power relay module is an electrical switch that is operated by an electromagnet. The electromagnet is activated by a separate low-power signal from a microcontroller. When activated, the electromagnet pulls to either open or close an electrical circuit.
W5100S-EVB-PicoWIZnet Pico is a microcontroller evaluation board based on the Raspberry Pi RP2040 and fully hardwired TCP/IP controller W5100S – and basically works the same as Raspberry Pi Pico board but with additional Ethernet via W5100S.
Circuit Diagram
Explanation
The VCC & GND pins of the Camera, IR sensor and 4ch Relay are connected to VCC and GND respectively. The IR sensor’s DOUT pin is connected to GP1 of the WIZnet Pico 2 and the output from WIZnet Pico 1 is connected to GP0 of the WIZnet Pico 2.
If the camera detects any human face, it will turn the GP0 of WIZnet Pico 2 to HIGH and when the IR sensor detects something it will turn the GP1 of WIZnet Pico 2 to LOW (refer to the link below for the human detection).
https://github.com/Innovation4x/WIZnetEVBPico-HumanDetection
When the GP0 and GP1 of WIZnet Pico 2 are HIGH and LOW respectively, the Relays connected to GP2, GP3, GP4 and GP5 are turned HIGH ie when any human is detected by the camera and then he/she sitting on his desk, the microcontroller will turn on the relays.
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