Overview
This greenhouse irrigation system, built by the customer on a Raspberry Pi 4, manages 14 separate solenoid valves through a 16-channel relay module, based on weight data from a single HM711 load cell and temperature/humidity readings from a DHT11 sensor. Some valves activate once a specific weight threshold is reached, others run for gradually increasing durations based on elapsed days. The customer had built the system themselves, but some connections and code weren't working correctly; we fixed the hardware wiring and wrote working code matching their required calculations, then delivered it.
Goals and Objectives
Our customer wanted to manage 14 different irrigation zones in their greenhouse from a single Raspberry Pi, automatically, based on both live weight readings and day-based schedules — but their self-built system had hardware and software issues. After listening to their needs, our goal was to verify and fix the existing hardware connections and deliver reliable code that matched their exact calculation logic.
Development Process
We first listened to the customer's needs and the issues in the existing system, then examined the hardware connections one by one. We tested the HM711 weight sensor, the DHT11 temperature/humidity sensor, and each of the 14 solenoid valves connected through the 16-channel relay module individually, using point-to-point wiring. We then integrated everything on the Raspberry Pi 4 and ran full system tests, writing Python code matching the customer's required weight- and time-based irrigation calculations. Within a week, we delivered the complete working system along with sample code.
