In the last blog (blog1) i explained about the overall concept and designs. In this blog i write about how i have interfaced sensors which
required for this "Smart Coposter".
Total Three sensing part in this design and 3 sensors are used.
For the composting process temperature is an important parameter to sense the compositing stages. Based on the temperature we can divide the stages
into three stages.
1. WARM (IDLE)
These stages are classified based on the temperature level. In general people use a composter temperature sensor to measure manually. I'm going to
use the MLX90614 - IR based temperature sensor in my smart composter design.
This MLX90614 sensor has 4 Pins, (VDD, GND, SCL, SDA) Interfaced to the PSoC6 via I2C interface. I have used the default I2C Pins P6_0, P6_1 for
I2C communication. Two temperature levels are read from the MLX9061 sensor (Ambient and Object Temperature).
In this part the spinning of Composter is sensed with the help of Bosch 6 axis Accelerometer (BLI16)). This sensor is interfaced to PSoC6 over I2C.
I have used a Cypress Eink Display Shield board which has a motion sensor. My initial thought was to use Infineon 3D magnetic sensor to detect
the spin but chooses motion sensor, since the setup is going to be mounted on the composter.
The rotating angle is calculated from the Accelerometer data. And used logic to sense the spin of Composter
The Eink display was used to show the Temperature, Composter state and Alerts. I chose Eink over TFT since it's battery operated low power design.
In this part the Tilt switch is used detect the open/close of Composter lid , which helps the user for tracking the load/unload information .
The tool MTB i used for developing the software. I started with PSoC6 Empty application and then added required components via library manager.
I used different FreeRTOS tasks for running Eink Display, Sensor and Cloud. For Eink dislay graphics i have used emWin tool to create bitmap arrays.
All the sensor values are pinted on consloe like below.
The sensor working demo is shown below.
The next blog (blog3) tells about the Cloud (AWS) interface and Alexa Skills.