Sensor-Actuator System

This is a multithreaded sensor monitoring and actuator control system implemented in C++. It simulates sensors and an LED actuator, allowing users to monitor sensor values and adjust thresholds dynamically through a command interface.

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Features

• Sensor Monitoring: Periodically reads data from temperature and humidity sensors.
• Threshold-based Actuation: Controls an LED actuator based on whether sensor values exceed their thresholds.
• Logging: Logs sensor data periodically to a file.
• Dynamic Threshold Adjustment: Users can update sensor thresholds in real-time through a command-line interface.
• Multithreading: Utilizes multiple threads for concurrent tasks, including sensor monitoring, logging, actuator control, and command input handling.

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System Components

1. Sensors

• TemperatureSensor
• HumiditySensor

Each sensor has:

• A name (e.g., Temperature, Humidity)
• A current value (simulated)
• A threshold

2. Actuator

• LEDController: Turns the LED ON or OFF based on whether any sensor value exceeds its threshold.

3. Tasks

• Sensor Task: Reads sensor values periodically.
• Logging Task: Writes sensor values to a log file.
• Actuator Task: Checks sensor thresholds and controls the LED state.
• Command Interface Task: Handles user input for updating thresholds.
• Input Capture Task: Captures and queues user commands.

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How It Works

1. Starting the System:
   • The system initializes sensors and starts multiple threads.
2. Sensor Value Updates:
   • Sensors periodically update their values (simulated).
3. Threshold Checking:
   • The LED state is updated if any sensor value exceeds its threshold.
4. Dynamic Input:
   • Users can update thresholds using commands like:

     <SensorName> <NewThreshold>
     

     Example:

     Temperature 30
     

5. Logging:
   • Sensor data is periodically logged to a file (sensor_log.txt).

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Setup and Usage

1. Requirements

• g++ (C++14 or later)
• POSIX-compliant system (for pthreads)

2. Build Instructions

Run the following command to compile the program:

g++ -std=c++14 -pthread main.cpp system.cpp -o sensor_system

3. Run the Program

./sensor_system

4. User Commands

When prompted, you can enter commands to update sensor thresholds:

Enter sensor name and new threshold (e.g., Temperature 25):

Example inputs:

• Temperature 30
• Humidity 40

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File Structure

.
├── main.cpp         # Program entry point
├── system.cpp       # Implementation of system tasks and functionality
├── system.h         # Declarations of sensors, actuators, and tasks
├── sensor_log.txt   # Log file for sensor data (created at runtime)
└── README.md        # Documentation for the system

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Key Components in Code

Threshold Logic for LED

The LED is controlled in the actuatorTask:

bool state = sensor->getValue() > sensor->getThreshold();
led->control(state);

If any sensor's value exceeds its threshold, the LED turns ON. Otherwise, it remains OFF.

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Example Output

Startup

Starting sensor system...
Threads started.
You can now enter commands in the format: <SensorName> <NewThreshold>
Enter sensor name and new threshold (e.g., Temperature 25):

Commands

Temperature 30
Command queued: Temperature with threshold 30
Threshold for Temperature updated to 30

Sensor Updates

Temperature Value: 28.3
Humidity Value: 38.6
LED is ON
Temperature Value: 24.5
Humidity Value: 35.1
LED is OFF

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Improvements and Customization

• Add more sensors and actuators.
• Implement additional control logic (e.g., hysteresis for actuators).
• Improve logging with timestamps.

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License

This project is open-source and free to use for educational purposes.