Hardware
The entire project is based on a Raspberry Pi 3 Model B+ with various sensors and corresponding software. Of course you can also use other components than the ones listed here. The brand names are only examples. For details, please refer to the submenu on the right.
I used the following components for my setup (Amazon list):
- Raspberry Pi 3 Modell B+
- Single point load cell for weighing the gas cylinder (Bosche H10A for 20 kg)
- hx711 for evaluating the signals from the load cell (ARCELI CJMCU-711 HX711)
- ADXL345 Triple-Axis Accelerometer to determine the position of the caravan (Adafruit ADXL345)
- BME280 Barometric sensor for temperature, humidity and air pressure (AZDelivery GY-BME280)
- DS18B20 Temperature sensor encapsulated in stainless steel AZDelivery 1M Cable DS18B20
- RGB LED to indicate the tilt angle
- various buttons, resistors, diodes
The use of Cat6 network cables is intended for cabling in caravans. As a rule, the routing of 2 Cat6 cables to the rear and to the other side of the caravan and 3 cables from the Raspberry to the front of the caravan or motorhome should be sufficient.
Cat6 cables are suitable because they are already twisted in pairs, which is absolutely necessary, for example, to extend the I2C bus.
The assembly of the many components and sensors is not trivial, thanks to the GPIO bar of the Raspberry Pi with two extensions of GPIO to perform well. Details can be found in the circuit diagram and the board design.
Some of the housings for the sensors were created on the 3D printer.
