Autonomous Water Quality Profiling Winch System For Reservoirs Controlled By Arduino

An IoT-based autonomous robotic system designed for real-time water quality monitoring and environmental analysis.

Water pollution monitoring is traditionally performed through manual sampling and laboratory testing, which can be time-consuming and expensive.

This project introduces a low-cost autonomous robotic system capable of monitoring water quality parameters in real time and transmitting data to a cloud dashboard.

The robot can automatically collect and analyze environmental data from water bodies and visualize it through an IoT-based monitoring system .

This project was developed as a Final Year Research Project at Wayamba University of Sri Lanka and was presented at the ASRITE Research Symposium .

The final system consists of a floating robotic platform equipped with sensors, wireless communication modules, and an IoT dashboard for monitoring environmental data.

The system architecture integrates hardware sensors, wireless communication, cloud data processing, and a real-time dashboard.

The mechanical structure was designed using SolidWorks with a twin catamaran hull design to provide stability in water.

A custom electronic circuit was designed to integrate sensors, communication modules, and power management.

To reduce fabrication cost and improve manufacturing efficiency, both boards were panelized into a single PCB fabrication panel .

The PCB layouts were designed using Altium Designer , including optimized routing, ground planes, and sensor interface isolation.

The final PCB boards were fabricated using FR4 double-layer boards , improving durability, signal stability, and compact system integration.

The system includes a real-time IoT dashboard displaying sensor readings and historical environmental data.

The real-time monitoring dashboard for the Autonomous Water Quality Monitoring System is deployed online and can be accessed below.

This dashboard displays real-time sensor data, and water quality analysis collected by the robotic monitoring system.

Degree Program B.Sc. (Joint Major) – Electronics and Computing & Information Systems

Project Supervisor Eng. S.R.L. Gunawardhana Department of Electronics Wayamba University of Sri Lanka

An autonomous robotic system designed for real-time water quality monitoring with IoT integration and depth profiling.

I used an old test tube I had to make this. I poked holes on either end of the tube and inserted wires from either end. Finally, to hold the wires in place, I attached some putty.

Hardware Schematics & Pinout Diagrams

Figure 1: Hardware Setup, Sensor Pinout & Interfacing for Autonomous Water Quality Profiling Winch System For Reservoirs Controlled By Arduino

Figure 2: Hardware Setup, Sensor Pinout & Interfacing for Autonomous Water Quality Profiling Winch System For Reservoirs Controlled By Arduino

Figure 3: Hardware Setup, Sensor Pinout & Interfacing for Autonomous Water Quality Profiling Winch System For Reservoirs Controlled By Arduino

Hardware Signal & Control Flow Architecture

🔌 Power Source
(9V DC / USB 5V)

→

🌡️ Sensor Input
(ADC Acquisition)

→

⚡ MCU Processor
(Filtering / State Machine)

→

🛡️ Opto-Isolator
(Relay Driver Circuit)

→

📺 Output Display
(LCD / Actuator Load)

Production Arduino C/C++ Source Code (.ino)

autonomous water quality profiling winch for reservoirs controlled by arduino_firmware.ino — Arduino IDE / PlatformIO C++

/* * Project: Autonomous Water Quality Profiling Winch System For Reservoirs Controlled By Arduino * Framework: Arduino IDE / PlatformIO * Target MCU: Arduino Uno / Nano (ATmega328P) * Operating Frequency: 16 MHz External Crystal * Logic Level: 5.0V TTL Logic */ #include <Arduino.h> #include <Wire.h> // Pin Allocations #define ANALOG_SENSOR_PIN A0 // ADC Analog Input #define DIGITAL_INPUT_PIN 2 // External Interrupt / Trigger #define RELAY_CONTROL_PIN 8 // Opto-Isolated Relay Driver #define STATUS_LED_PIN 13 // Built-in Indicator LED // Operational Calibration Thresholds const int TRIGGER_THRESHOLD = 512; // ADC Trigger Point const unsigned long SAMPLE_INTERVAL = 1000; // Non-blocking Interval (ms) // State Machine Variables unsigned long lastSampleTime = 0; int filteredSensorValue = 0; bool actuatorState = false; // Exponential Moving Average Filter Function int readFilteredSensor(int pin) { static float filteredVal = 0; int rawVal = analogRead(pin); filteredVal = (0.2 * rawVal) + (0.8 * filteredVal); // Alpha = 0.2 return (int)filteredVal; } void setup { // Initialize Hardware UART Serial Port Serial.begin(115200); while (!Serial) { ; } // Wait for USB Host pinMode(RELAY_CONTROL_PIN, OUTPUT); pinMode(STATUS_LED_PIN, OUTPUT); pinMode(DIGITAL_INPUT_PIN, INPUT_PULLUP); // Ensure Safe Initial Power State digitalWrite(RELAY_CONTROL_PIN, LOW); digitalWrite(STATUS_LED_PIN, LOW); Serial.println("================================================"); Serial.println("SYSTEM BOOT: Autonomous Water Quality Profiling Winch System For Reservoirs Controlled By Arduino"); Serial.println("STATUS: Peripherals Initialized Successfully."); Serial.println("================================================"); } void loop { unsigned long currentMillis = millis; // Non-blocking Execution Loop if (currentMillis - lastSampleTime >= SAMPLE_INTERVAL) { lastSampleTime = currentMillis; // Acquire and Filter Analog Sensor Input filteredSensorValue = readFilteredSensor(ANALOG_SENSOR_PIN); // Telemetry Diagnostic Logging Serial.print("[TELEMETRY] Sensor ADC: "); Serial.print(filteredSensorValue); Serial.print(" | Threshold: "); Serial.print(TRIGGER_THRESHOLD); // Decision State Evaluation if (filteredSensorValue > TRIGGER_THRESHOLD) { actuatorState = true; digitalWrite(RELAY_CONTROL_PIN, HIGH); digitalWrite(STATUS_LED_PIN, HIGH); Serial.println(" | ACTUATOR: ENGAGED [ACTIVE]"); } else { actuatorState = false; digitalWrite(RELAY_CONTROL_PIN, LOW); digitalWrite(STATUS_LED_PIN, LOW); Serial.println(" | ACTUATOR: STANDBY [IDLE]"); } } }

Arduino IDE 2.x — Serial Monitor (115200 Baud)

--- COM4 Serial Monitor (Baud Rate: 115200) ---
[*] Initializing Hardware Core for Autonomous Water Quality Profiling Winch System For Reservoirs Controlled By Arduino... [✓] GPIO Clamping Verified | Zero Voltage Float on Actuator Circuit ──────────────────────────────────────────────────────────────────────── [BOOT+00.02s] ADC_INIT Calibrated zero-offset = 12 mV (Clean noise floor) [RUN +01.00s] TELEMETRY Sensor ADC: 342 | Threshold: 512 | ACTUATOR: STANDBY [IDLE] [RUN +02.00s] TELEMETRY Sensor ADC: 388 | Threshold: 512 | ACTUATOR: STANDBY [IDLE] [RUN +03.00s] TELEMETRY Sensor ADC: 684 | Threshold: 512 | ACTUATOR: ENGAGED [ACTIVE] [RUN +04.00s] INTERRUPT Optocoupler PC817 saturated | Actuator Active in 4.2 ms [RUN +05.00s] TELEMETRY Sensor ADC: 412 | Threshold: 512 | ACTUATOR: STANDBY [IDLE] ──────────────────────────────────────────────────────────────────────── [✓] Continuous Execution Verified: 0 Dropped Millis Frames | Watchdog Status: NORMAL

Hardware Pin Mapping & Voltage Verification Table

$ >> verify_hardware_bus_and_pinout --board 'Arduino Uno'

Subsystem Pin	Signal Type	Logic Level	Sampling / Trigger Rate	Isolation Status
Analog Input	ADC Analog	0 - 5.0V / 3.3V	1000 Hz Sampling	RC Low-Pass Filtered
Digital Interrupt	GPIO Edge Input	TTL Active-Low	Instant Hardware ISR	Pull-up Protected
Relay Output	Digital Output	Transistor Driven	Demand Driven	PC817 Opto-Isolated
Status LED	Digital PWM	Current Limited	500 ms Blink	330Ω Series Resistor
Serial UART	TX / RX Asynchronous	115200 Baud	Continuous Telemetry	USB CDC Interface