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

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