mart/ev3/ex1/nl/ru/des/StayInFieldBehaviour.java

   1 package nl.ru.des;
   2
   3 import java.io.File;
   4
   5 import lejos.hardware.Button;
   6 import lejos.hardware.motor.EV3LargeRegulatedMotor;
   7 import lejos.hardware.sensor.NXTLightSensor;
   8 import lejos.robotics.SampleProvider;
   9
  10 public class StayInFieldBehaviour extends AvoidBehaviour{
  11         private SampleProvider light;
  12         private float[] samples;
  13         private float black, white, dist;
  14
  15         public StayInFieldBehaviour(NXTLightSensor lightSensor, EV3LargeRegulatedMotor leftMotor, EV3LargeRegulatedMotor rightMotor) {
  16                 super(rightMotor, leftMotor, new File("bound.wav"));
  17                 light = lightSensor.getRedMode();
  18                 samples = new float[light.sampleSize()];
  19                 calibrate();
  20                 dist = Math.abs(black-white);
  21         }
  22
  23         private void calibrate(){
  24                 LCDPrinter.print("Calibrate Light...");
  25                 //Get the black value
  26                 LCDPrinter.print("Place on black");
  27                 Button.waitForAnyPress();
  28                 light.fetchSample(samples, 0);
  29                 black = samples[0];
  30                 LCDPrinter.print("Black: " + black);
  31
  32                 //Get the white value
  33                 LCDPrinter.print("Place on white");
  34                 Button.waitForAnyPress();
  35                 light.fetchSample(samples, 0);
  36                 white = samples[0];
  37                 LCDPrinter.print("White: " + white);
  38
  39                 //Calculate the delta
  40                 dist = Math.abs(black-white);
  41         }
  42
  43         @Override
  44         public boolean takeControl() {
  45                 this.light.fetchSample(samples, 0);
  46                 return samples[0] < Math.abs(white - dist/2);
  47         }
  48 }