lejos.hardware.sensor.DexterThermalIRSensor Maven / Gradle / Ivy
Show all versions of lejos-ev3-api Show documentation
package lejos.hardware.sensor;
import lejos.hardware.port.I2CPort;
import lejos.hardware.port.Port;
import lejos.utility.Delay;
import lejos.utility.EndianTools;
/**
* Support for the Dexter Industries Thermal Infrared Sensor.
*
* The Dexter Industries Thermal Infrared Sensor reads surface temperatures of objects.
* It is a non-contact thermometer based on the Melexis MLX90614xCC. Detecting the infrared radiation
* from an object, the sensor can read object temperatures between -90\u00b0F and 700\u00b0F
* (-70\u00b0C and +380\u00b0C). The sensor has a high accuracy of 0.5\u00b0C and a resolution of 0.02\u00b0C.
*
* The Thermal Infrared Sensor reads both the ambient temperature (the temperature of the air
*around the sensor) and the surface temperature of the object that the sensor is pointed towards.
*
* @author Kirk P. Thompson
*
*/
/**
* Dexter Industries Thermal Infrared Sensor
* The Dexter Industries Thermal Infrared Sensor reads surface temperatures of objects.
*
*
* The code for this sensor has not been tested. Please report test results to
* the leJOS forum.
*
*
*
*
*
* Supported modes
*
*
* Mode name
* Description
* unit(s)
* Getter
*
*
* Object
* Measures the temperature of an objects surface
* Kelvin
* {@link #getObjectMode() }
*
*
* Ambient
* Measures the ambient temperature
* Kelvin
* {@link #getAmbientMode() }
*
*
*
*
*
* Sensor configuration
* The Emissivity value of the sensor can be configured using the {@link #setEmissivity} method.
*
*
*
* See Sensor datasheet
* See Sensor Product page
* See The
* leJOS sensor framework
* See {@link lejos.robotics.SampleProvider leJOS conventions for
* SampleProviders}
*
*
*
*
* @author Kirk P. Thompson
*
*/public class DexterThermalIRSensor extends I2CSensor {
private static final int I2C_ADDRESS = 0x0E;
private static final int REG_GET_OBJECT = 0x01;
private static final int REG_GET_AMBIENT = 0x00;
private static final int REG_GET_EMISSIVITY = 0x03;
private static final int REG_SET_EMISSIVITY = 0x02;
private static final int MAX_EMISSIVITY = 10000;
private byte [] buf = new byte[2];
/**
* Construct a sensor instance that is connected to port.
* @param port The NXT port to use
*/
public DexterThermalIRSensor(I2CPort port) {
super(port, I2C_ADDRESS);
init();
}
public DexterThermalIRSensor(Port port) {
super(port, I2C_ADDRESS);
init();
}
protected void init() {
setModes(new SensorMode[]{ new ObjectMode(), new AmbientMode() });
}
/**
* Set the sensor's emissivity value. Valid values are
* 0.01-1.0. The emissivity is stored in non-volatile memory of the sensor and will be
* retained even after power-off.
*
* < 0.01 returns with no action. > 1.0 sets to 1.0
* @param emissivity The value to set emissivity coefficient to
*/
public synchronized void setEmissivity(float emissivity){
int intEmissivity = Math.round(emissivity * MAX_EMISSIVITY);
if (intEmissivity<100) return;
if (intEmissivity>MAX_EMISSIVITY) intEmissivity=MAX_EMISSIVITY;
EndianTools.encodeShortBE(intEmissivity, buf, 0);
sendData(REG_SET_EMISSIVITY, buf, 2);
Delay.msDelay(500);
}
/**
* Read the current emissivity value.
*
* Caveat Emptor: The sensor appears to only return the emissivity value
* after it was intially set after power-up with setEmissivity(). It doesn't seem
* to retrieve it from EEPROM.
*
* @return The emissivity value from 0.01 to 1.0
*/
public float getEmissivity(){
getData(REG_GET_EMISSIVITY, buf, 2);
return EndianTools.decodeUShortLE(buf, 0) / 65535f;
}
@Override
public String getProductID() {
return "dTIR";
}
@Override
public String getVendorID() {
return "Dexter";
}
/**
* Dexter Industries Thermal Infrared Sensor, Object mode
* Measures the temperature of an objects surface
*
*
* Size and content of the sample
* The sample contains one elements representing the surface temperature (in Kelvin) of an object. the sensor can read object temperatures between -90\u00b0F and 700\u00b0F
* (-70\u00b0C and +380\u00b0C). The sensor has a high accuracy of 0.5\u00b0C and a resolution of 0.02\u00b0C.
*
*
*
* @return A sampleProvider
* See {@link lejos.robotics.SampleProvider leJOS conventions for
* SampleProviders}
* See Sensor datasheet
*/
public SensorMode getObjectMode() {
return getMode(0);
}
private class ObjectMode implements SensorMode {
@Override
public int sampleSize() {
return 1;
}
@Override
public void fetchSample(float[] sample, int offset) {
getData(REG_GET_OBJECT, buf, 2);
sample[offset] = .02f * EndianTools.decodeUShortLE(buf, 0); // degrees Kelvin
}
@Override
public String getName() {
return "Object";
}
}
/**
* Dexter Industries Thermal Infrared Sensor, Ambient mode
* Measures the ambient temperature
*
*
* Size and content of the sample
* The sample contains one elements representing the ambient temperature (in Kelvin) (the temperature of the air around the sensor).
*
*
*
* @return A sampleProvider
* See {@link lejos.robotics.SampleProvider leJOS conventions for
* SampleProviders}
* See Sensor datasheet
*/ public SensorMode getAmbientMode() {
return getMode(1);
}
private class AmbientMode implements SensorMode {
@Override
public int sampleSize() {
return 1;
}
@Override
public void fetchSample(float[] sample, int offset) {
getData(REG_GET_AMBIENT, buf, 2);
sample[offset] = .02f * EndianTools.decodeUShortLE(buf, 0); // degrees Kelvin
}
@Override
public String getName() {
return "Ambient";
}
}
}