94 lines
3.4 KiB
C++
94 lines
3.4 KiB
C++
//Made by POLULU
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#include <QTRSensors.h>
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// This example is designed for use with eight RC QTR sensors. These
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// reflectance sensors should be connected to digital pins 3 to 10. The
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// sensors' emitter control pin (CTRL or LEDON) can optionally be connected to
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// digital pin 2, or you can leave it disconnected and remove the call to
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// setEmitterPin().
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//
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// The setup phase of this example calibrates the sensors for ten seconds and
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// turns on the Arduino's LED (usually on pin 13) while calibration is going
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// on. During this phase, you should expose each reflectance sensor to the
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// lightest and darkest readings they will encounter. For example, if you are
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// making a line follower, you should slide the sensors across the line during
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// the calibration phase so that each sensor can get a reading of how dark the
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// line is and how light the ground is. Improper calibration will result in
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// poor readings.
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//
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// The main loop of the example reads the calibrated sensor values and uses
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// them to estimate the position of a line. You can test this by taping a piece
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// of 3/4" black electrical tape to a piece of white paper and sliding the
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// sensor across it. It prints the sensor values to the serial monitor as
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// numbers from 0 (maximum reflectance) to 1000 (minimum reflectance) followed
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// by the estimated location of the line as a number from 0 to 5000. 1000 means
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// the line is directly under sensor 1, 2000 means directly under sensor 2,
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// etc. 0 means the line is directly under sensor 0 or was last seen by sensor
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// 0 before being lost. 5000 means the line is directly under sensor 5 or was
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// last seen by sensor 5 before being lost.
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QTRSensors qtr;
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const uint8_t SensorCount = 8;
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uint16_t sensorValues[SensorCount];
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void setup()
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{
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// configure the sensors
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qtr.setTypeRC();
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qtr.setSensorPins((const uint8_t[]){10, 11, 12, 14, 15, 16, 18, 19}, SensorCount);
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qtr.setEmitterPin(7);
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delay(500);
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pinMode(LED_BUILTIN, OUTPUT);
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digitalWrite(LED_BUILTIN, HIGH); // turn on Arduino's LED to indicate we are in calibration mode
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// 2.5 ms RC read timeout (default) * 10 reads per calibrate() call
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// = ~25 ms per calibrate() call.
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// Call calibrate() 400 times to make calibration take about 10 seconds.
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for (uint16_t i = 0; i < 400; i++)
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{
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qtr.calibrate();
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}
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digitalWrite(LED_BUILTIN, LOW); // turn off Arduino's LED to indicate we are through with calibration
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// print the calibration minimum values measured when emitters were on
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Serial.begin(9600);
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for (uint8_t i = 0; i < SensorCount; i++)
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{
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Serial.print(qtr.calibrationOn.minimum[i]);
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Serial.print(' ');
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}
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Serial.println();
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// print the calibration maximum values measured when emitters were on
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for (uint8_t i = 0; i < SensorCount; i++)
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{
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Serial.print(qtr.calibrationOn.maximum[i]);
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Serial.print(' ');
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}
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Serial.println();
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Serial.println();
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delay(1000);
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}
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void loop()
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{
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// read calibrated sensor values and obtain a measure of the line position
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// from 0 to 5000 (for a white line, use readLineWhite() instead)
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uint16_t position = qtr.readLineBlack(sensorValues);
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// print the sensor values as numbers from 0 to 1000, where 0 means maximum
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// reflectance and 1000 means minimum reflectance, followed by the line
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// position
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for (uint8_t i = 0; i < SensorCount; i++)
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{
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Serial.print(sensorValues[i]);
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Serial.print('\t');
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}
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Serial.println(position);
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delay(250);
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}
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