To demonstrate the use of neqto, the team installed a bump sensor and a temperature (+humidity) sensor in a mini fridge, which shows the usecase for large refrigerators that have to be checked and closed. The refrigerator demo used the following sensors with the bridge
— A temperature and humidity sensor – HTS221
— A bump sensor – D2SW
The temperature and humidity sensor was mounted on the bridge directly and the bump sensor was connected to the breakout on the I/O board using the pins GND, 3.3V, and the digital interrupt pin, and then it was mounted on the door walls so that it closes when the door is closed. The interrupt when the door opens would trigger a function that would poll for the time it has remained open and if it has been open for more than 10 seconds, it would send a MQTT message that would then trigger an action to send a slack message every 10 seconds for as long as the door is open. Also the temperature and humidity would be sent to the cloud every 3 minutes and would send a slack message if it crosses a certain limit.
The temperature and humidity sensor connects to the bridge using the I2C interface and the bump sensor uses the digital interrupt. When the door is open, and so is the sensor, the interrupt pin is pulled high and when closed, the switch is closed, and the digital interrupt input pin is pulled low.
The screenshots and pictures below show the messages on slack, the humidity/temperature graphs on the console and the schematic of the setup with the temperature sensor module and the bump sensor.
This demo shows a concept that can be applied to other areas and sectors like –
— Maintaining building security by checking doors
— Preventing property damage by ensuring windows and doors are closed
— Preventing livestock from running out
— Toilet stalls occupancy in expos and events and large buildings