Multi-Sensor Systems

Learn how to create robust multi-sensor systems that combine analog sensors, digital sensors, filtering, calibration, and alert systems.

Complete Environmental Monitoring System

Combine multiple sensor types for comprehensive environmental monitoring:

#define ENABLE_SENSOR_MODULE_V2
#define ENABLE_SENSOR_RTC_DS3231_V2
#define ENABLE_SENSOR_BME680_V2
#define ENABLE_SENSOR_GP2Y_DUST_V2
#define ENABLE_SENSOR_MQ_V2
#define ENABLE_SENSOR_UTILITY_V2
#include "Kinematrix.h"

SensorModuleV2 sensorModule;

void setup() {
    Serial.begin(115200);
    Serial.println("RTC and Environmental Sensors Example");
    
    // Add multiple sensor types
    sensorModule.addSensor("rtc", new RTCDS3231SensV2());
    sensorModule.addSensor("bme680", new BME680SensV2());
    sensorModule.addSensor("dust", new GP2YDustSensV2(GP2Y1010AU0F, 7, A3));
    sensorModule.addSensor("mq2", new MQSensV2("Arduino", 5.0, 10, A2, "MQ-2"));
    
    sensorModule.init();
    
    // Enable RTC temperature reading
    RTCDS3231SensV2* rtc = (RTCDS3231SensV2*)sensorModule.getSensorByName("rtc");
    if (rtc) {
        rtc->enableTemperature(true);
    }
    
    Serial.println("RTC and environmental monitoring started");
}

void loop() {
    sensorModule.update();
    
    if (sensorModule.isUpdated("rtc")) {
        Serial.print("Time: ");
        Serial.print((int)sensorModule["rtc"]["hour"]);
        Serial.print(":");
        Serial.print((int)sensorModule["rtc"]["minute"]);
        Serial.print(":");
        Serial.println((int)sensorModule["rtc"]["second"]);
    }
    
    if (sensorModule.isUpdated("bme680")) {
        Serial.print("BME680 - Temp: ");
        Serial.print((float)sensorModule["bme680"]["temperature"]);
        Serial.print("°C, Humidity: ");
        Serial.print((float)sensorModule["bme680"]["humidity"]);
        Serial.println("%");
    }
    
    if (sensorModule.isUpdated("dust")) {
        Serial.print("Dust: ");
        Serial.print((float)sensorModule["dust"]["density"]);
        Serial.println(" μg/m³");
    }
    
    delay(2000);
}

Source:

/home/daytona/workspace/source/example/sensors/SensorModuleV2/SensorModule/SensorModuleV2/RTCandEnvironmentalSensors/RTCandEnvironmentalSensors.ino:1

Multi-Sensor with Filters and Alerts

Combine different sensor types with advanced filtering:

#define ENABLE_SENSOR_MODULE_V2
#define ENABLE_SENSOR_FILTER_V2
#define ENABLE_SENSOR_DHT_V2
#define ENABLE_SENSOR_ANALOG_V2
#define ENABLE_SENSOR_BME680_V2
#define ENABLE_SENSOR_MQ_V2
#define ENABLE_SENSOR_UTILITY_V2
#include "Kinematrix.h"

SensorModuleV2 sensorModule;

void setup() {
    Serial.begin(115200);
    Serial.println("Multi Sensor with Filters Example");
    
    // Add diverse sensor types
    sensorModule.addSensor("dht", new DHTSensV2(2, DHT22));
    sensorModule.addSensor("analog1", new AnalogSensV2(A0, 5.0, 1023));
    sensorModule.addSensor("analog2", new AnalogSensV2(A1, 3.3, 1023));
    sensorModule.addSensor("bme680", new BME680SensV2());
    sensorModule.addSensor("mq135", new MQSensV2("Arduino", 5.0, 10, A2, "MQ-135"));
    
    sensorModule.init();
    
    // Apply moving average filter to analog sensor
    FilterParams movingAvgParams;
    movingAvgParams.movingAverage.windowSize = 5;
    sensorModule.attachFilter("analog1", "volt", FILTER_MOVING_AVERAGE, movingAvgParams);
    
    // Apply Kalman filter to temperature
    FilterParams kalmanParams;
    kalmanParams.kalman.processNoise = 0.01;
    kalmanParams.kalman.measurementNoise = 0.1;
    sensorModule.attachFilter("dht", "temperature", FILTER_KALMAN, kalmanParams);
    
    Serial.println("Filters attached to sensors");
}

void loop() {
    sensorModule.update();
    
    if (sensorModule.isUpdated("dht")) {
        float temp = sensorModule.getFilteredValue("dht", "temperature");
        Serial.print("Filtered Temperature: ");
        Serial.println(temp);
    }
    
    if (sensorModule.isUpdated("analog1")) {
        float volt = sensorModule.getFilteredValue("analog1", "volt");
        Serial.print("Filtered Voltage: ");
        Serial.println(volt);
    }
    
    delay(2000);
}

Source:

/home/daytona/workspace/source/example/sensors/SensorModuleV2/SensorModule/SensorModuleV2/MultiSensorWithFilters/MultiSensorWithFilters.ino:1

Advanced Calibration System

Manage calibration across multiple sensor types:

#define ENABLE_SENSOR_MODULE_V2
#define ENABLE_SENSOR_CALIBRATION_MODULE_V2
#define ENABLE_SENSOR_ANALOG_V2
#define ENABLE_SENSOR_MLX90614_V2
#define ENABLE_SENSOR_INA219_V2
#include "Kinematrix.h"

SensorCalibrationModuleV2 calibrationModule;

void setup() {
    Serial.begin(115200);
    Serial.println("Multiple Calibration Types Example");
    
    // Add different sensor types
    calibrationModule.addSensor("analog1", new AnalogSensV2(A0, 5.0, 1023));
    calibrationModule.addSensor("analog2", new AnalogSensV2(A1, 3.3, 1023));
    calibrationModule.addSensor("analog3", new AnalogSensV2(A2, 5.0, 1023));
    calibrationModule.addSensor("mlx90614", new MLX90614SensV2());
    calibrationModule.addSensor("ina219", new INA219SensV2());
    
    calibrationModule.init();
    
    // Add calibration entries for each sensor value
    calibrationModule.addCalibrationEntry("analog1", "volt");
    calibrationModule.addCalibrationEntry("analog2", "volt");
    calibrationModule.addCalibrationEntry("analog3", "volt");
    calibrationModule.addCalibrationEntry("mlx90614", "objectTemp");
    calibrationModule.addCalibrationEntry("mlx90614", "ambientTemp");
    calibrationModule.addCalibrationEntry("ina219", "power");
    
    // Apply different calibration methods
    calibrationModule.calibrateOnePoint("analog1", "volt", 3.3);
    calibrationModule.calibrateTwoPoint("analog2", "volt", 1.0, 0.95, 4.0, 4.08);
    calibrationModule.calibrateOnePoint("analog3", "volt", 2.5);
    calibrationModule.calibrateTwoPoint("mlx90614", "objectTemp", 25.0, 24.8, 80.0, 80.5);
    calibrationModule.calibrateTwoPoint("mlx90614", "ambientTemp", 25.0, 24.8, 80.0, 80.5);
    calibrationModule.calibrateOnePoint("ina219", "power", 5.0);
    
    Serial.println("Multiple calibration types configured");
}

void loop() {
    calibrationModule.update();
    
    if (calibrationModule.isUpdated("analog1")) {
        Serial.print("A1 Linear - Raw: ");
        Serial.print((float)calibrationModule["analog1"]["volt"]);
        Serial.print("V, Cal: ");
        Serial.print((float)calibrationModule.getCalibratedValue("analog1", "volt"));
        Serial.println("V");
    }
    
    if (calibrationModule.isUpdated("analog2")) {
        Serial.print("A2 TwoPoint - Raw: ");
        Serial.print((float)calibrationModule["analog2"]["volt"]);
        Serial.print("V, Cal: ");
        Serial.print((float)calibrationModule.getCalibratedValue("analog2", "volt"));
        Serial.println("V");
    }
    
    if (calibrationModule.isUpdated("mlx90614")) {
        Serial.print("MLX Temp - Raw: ");
        Serial.print((float)calibrationModule["mlx90614"]["objectTemp"]);
        Serial.print("°C, Cal: ");
        Serial.print((float)calibrationModule.getCalibratedValue("mlx90614", "objectTemp"));
        Serial.println("°C");
    }
    
    delay(2000);
}

Source:

/home/daytona/workspace/source/example/sensors/SensorModuleV2/SensorModule/SensorModuleCalibrationV2/MultipleCalibrationTypes/MultipleCalibrationTypes.ino:1

Multiple Abstract Sensors

Use abstract sensors for testing and simulation:

#define ENABLE_SENSOR_MODULE_V2
#define ENABLE_SENSOR_ABSTRACT_V2
#define ENABLE_SENSOR_UTILITY_V2
#include "Kinematrix.h"

SensorModuleV2 sensorModule;

void setup() {
    Serial.begin(115200);
    Serial.println("Multiple AbstractSensV2 Example");
    
    // Different abstract sensor modes
    sensorModule.addSensor("random", new AbstractSensV2(0));              // Random values
    sensorModule.addSensor("fixed", new AbstractSensV2(1, 42.5));         // Fixed value
    sensorModule.addSensor("range1", new AbstractSensV2(2, 100.0));       // Range 0-100
    sensorModule.addSensor("range2", new AbstractSensV2(3, 20.0, 80.0));  // Range 20-80
    
    sensorModule.init();
    
    // Configure update intervals
    AbstractSensV2* randomSensor = (AbstractSensV2*)sensorModule.getSensorByName("random");
    if (randomSensor) randomSensor->setUpdateInterval(500);
    
    AbstractSensV2* fixedSensor = (AbstractSensV2*)sensorModule.getSensorByName("fixed");
    if (fixedSensor) fixedSensor->setUpdateInterval(1000);
    
    Serial.println("Multiple abstract sensors with different modes initialized");
}

void loop() {
    sensorModule.update();
    
    if (sensorModule.isUpdated("random")) {
        Serial.print("Random Mode - Value: ");
        Serial.print((float)sensorModule["random"]["value"]);
        Serial.print(", Sine: ");
        Serial.println((float)sensorModule["random"]["sine"]);
    }
    
    if (sensorModule.isUpdated("fixed")) {
        Serial.print("Fixed Mode - Value: ");
        Serial.print((float)sensorModule["fixed"]["value"]);
        Serial.print(", Triangle: ");
        Serial.println((float)sensorModule["fixed"]["triangle"]);
    }
    
    if (sensorModule.isUpdated("range1")) {
        Serial.print("Range1 (0-100) - Value: ");
        Serial.println((float)sensorModule["range1"]["value"]);
    }
    
    if (sensorModule.isUpdated("range2")) {
        Serial.print("Range2 (20-80) - Value: ");
        Serial.println((float)sensorModule["range2"]["value"]);
    }
    
    delay(200);
}

Source:

/home/daytona/workspace/source/example/sensors/SensorModuleV2/SensorList/AbstractSensV2/MultipleAbstractSensors/MultipleAbstractSensors.ino:1

System Architecture Best Practices

Organize Sensors by Function

Group related sensors together:

// Environmental sensors
sensorModule.addSensor("temp_indoor", new DHTSensV2(2, DHT22));
sensorModule.addSensor("temp_outdoor", new BME680SensV2());

// Power monitoring
sensorModule.addSensor("power_main", new INA219SensV2());
sensorModule.addSensor("power_backup", new INA219SensV2(0x41));

// Analog inputs
sensorModule.addSensor("pressure", new AnalogSensV2(A0, 5.0, 1023));
sensorModule.addSensor("flow", new AnalogSensV2(A1, 5.0, 1023));

Apply Appropriate Filters

Choose filters based on sensor characteristics:

// Slow-changing values: Moving Average
FilterParams movingAvg;
movingAvg.movingAverage.windowSize = 10;
sensorModule.attachFilter("temp_indoor", "temperature", FILTER_MOVING_AVERAGE, movingAvg);

// Fast-changing values: Kalman
FilterParams kalman;
kalman.kalman.processNoise = 0.01;
kalman.kalman.measurementNoise = 0.1;
sensorModule.attachFilter("pressure", "volt", FILTER_KALMAN, kalman);

Set Up Alert Thresholds

Configure alerts for critical values:

// Temperature alerts (outside range)
sensorModule.setThreshold("temp_indoor", "temperature", 18.0, 26.0, ALERT_OUTSIDE);

// Pressure alerts (above threshold)
sensorModule.setThreshold("pressure", "volt", 4.5, 5.0, ALERT_ABOVE);

// Flow alerts (below threshold)
sensorModule.setThreshold("flow", "volt", 0.5, 1.0, ALERT_BELOW);

Calibrate for Accuracy

Apply calibration where precision matters:

calibrationModule.addCalibrationEntry("pressure", "volt");
calibrationModule.calibrateTwoPoint("pressure", "volt", 1.0, 0.98, 4.0, 4.05);

Performance Considerations

Update Intervals

Optimize sensor update rates based on requirements:

// Fast sensors (100ms)
analogSensor->setUpdateInterval(100);

// Medium sensors (1s)
dhtSensor->setUpdateInterval(1000);

// Slow sensors (5s)
bme680Sensor->setUpdateInterval(5000);

Memory Management

// Use pointers for dynamic sensor creation
BME680SensV2* bme = new BME680SensV2();
sensorModule.addSensor("bme680", bme);

// SensorModule manages memory automatically
// No need to delete manually

Checking Updates Efficiently

void loop() {
    sensorModule.update();  // Update all sensors once
    
    // Only process sensors that have new data
    if (sensorModule.isUpdated("sensor1")) {
        // Process sensor1 data
    }
    
    if (sensorModule.isUpdated("sensor2")) {
        // Process sensor2 data
    }
}

Complete System Example

Hardware Setup

ESP32 Connections:

I2C Bus:
- BME680: SDA=21, SCL=22, Addr=0x76
- RTC DS3231: SDA=21, SCL=22, Addr=0x68
- MLX90614: SDA=21, SCL=22, Addr=0x5A

Digital:
- DHT22: GPIO 2 (with 10kΩ pull-up)

Analog:
- Pressure Sensor: A0 (0-5V)
- Flow Sensor: A1 (0-5V)
- Gas Sensor MQ-135: A2 (0-5V)

Software Integration

#define ENABLE_SENSOR_MODULE_V2
#define ENABLE_SENSOR_CALIBRATION_MODULE_V2
#define ENABLE_SENSOR_FILTER_V2
#define ENABLE_SENSOR_ALERT_SYSTEM_V2
#define ENABLE_SENSOR_BME680_V2
#define ENABLE_SENSOR_DHT_V2
#define ENABLE_SENSOR_ANALOG_V2
#define ENABLE_SENSOR_RTC_DS3231_V2
#define ENABLE_SENSOR_UTILITY_V2
#include "Kinematrix.h"

SensorCalibrationModuleV2 sensorSystem;

void setup() {
    Serial.begin(115200);
    
    // Add all sensors
    sensorSystem.addSensor("bme680", new BME680SensV2());
    sensorSystem.addSensor("dht22", new DHTSensV2(2, DHT22));
    sensorSystem.addSensor("rtc", new RTCDS3231SensV2());
    sensorSystem.addSensor("pressure", new AnalogSensV2(A0, 5.0, 4095));
    sensorSystem.addSensor("flow", new AnalogSensV2(A1, 5.0, 4095));
    
    sensorSystem.init();
    
    // Configure filters
    FilterParams kalman;
    kalman.kalman.processNoise = 0.01;
    kalman.kalman.measurementNoise = 0.1;
    sensorSystem.attachFilter("bme680", "temperature", FILTER_KALMAN, kalman);
    sensorSystem.attachFilter("pressure", "volt", FILTER_KALMAN, kalman);
    
    // Configure alerts
    sensorSystem.setThreshold("bme680", "temperature", 18.0, 28.0, ALERT_OUTSIDE);
    sensorSystem.setThreshold("pressure", "volt", 4.0, 5.0, ALERT_ABOVE);
    
    // Apply calibration
    sensorSystem.addCalibrationEntry("pressure", "volt");
    sensorSystem.calibrateTwoPoint("pressure", "volt", 1.0, 0.95, 4.0, 4.08);
    
    Serial.println("Multi-sensor system initialized");
}

void loop() {
    sensorSystem.update();
    
    // Process each sensor type
    if (sensorSystem.isUpdated("bme680")) {
        float temp = sensorSystem.getFilteredValue("bme680", "temperature");
        bool alert = sensorSystem.isAlertActive("bme680", "temperature");
        Serial.printf("BME680: %.2f°C [Alert: %s]\n", temp, alert ? "YES" : "NO");
    }
    
    if (sensorSystem.isUpdated("pressure")) {
        float cal = sensorSystem.getCalibratedValue("pressure", "volt");
        Serial.printf("Pressure: %.2fV (calibrated)\n", cal);
    }
    
    delay(1000);
}

Next Steps

Environmental Monitoring

Focus on environmental sensor applications

Analog Sensors

Deep dive into analog sensor processing

Digital Sensors

Master I2C and digital protocols

Sensor Examples

Module Examples

AutoLight Examples

Multi-Sensor Systems

Complete Environmental Monitoring System

Multi-Sensor with Filters and Alerts

Advanced Calibration System

Multiple Abstract Sensors

System Architecture Best Practices

Performance Considerations

Update Intervals

Memory Management

Checking Updates Efficiently

Complete System Example

Hardware Setup

Software Integration

Next Steps

Environmental Monitoring

Analog Sensors

Digital Sensors

Build docs developers (and LLMs) love

Sensor Examples

Module Examples

AutoLight Examples

​Complete Environmental Monitoring System

​Multi-Sensor with Filters and Alerts

​Advanced Calibration System

​Multiple Abstract Sensors

​System Architecture Best Practices

​Performance Considerations

​Update Intervals

​Memory Management

​Checking Updates Efficiently

​Complete System Example

​Hardware Setup

​Software Integration

​Next Steps

Environmental Monitoring

Analog Sensors

Digital Sensors

Build docs developers (and LLMs) love

Complete Environmental Monitoring System

Multi-Sensor with Filters and Alerts

Advanced Calibration System

Multiple Abstract Sensors

System Architecture Best Practices

Performance Considerations

Update Intervals

Memory Management

Checking Updates Efficiently

Complete System Example

Hardware Setup

Software Integration

Next Steps