MovLizard.java

import lejos.nxt.Button;
import lejos.nxt.MotorPort;
import lejos.nxt.NXTRegulatedMotor;
import lejos.nxt.SensorPort;
import lejos.nxt.TouchSensor;
import lejos.nxt.UltrasonicSensor;
import lejos.util.Delay;

public class MovLizard {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		NXTRegulatedMotor motora = new NXTRegulatedMotor(MotorPort.A);
		NXTRegulatedMotor motorb = new NXTRegulatedMotor(MotorPort.B);
		TouchSensor sensora = new TouchSensor(SensorPort.S1);
		TouchSensor sensorb = new TouchSensor(SensorPort.S2);
		UltrasonicSensor sensor3 = new UltrasonicSensor(SensorPort.S3);

		initWalk(motora, motorb, sensora, sensorb);

		while (!Button.ESCAPE.isPressed()) {
			motora.backward();
			motorb.backward();
			// ------------------------
			if (sensor3.getDistance() <= 30) {
				synchronize(motora, motorb, sensora, sensorb);
				turn(motora, motorb);
				initWalk(motora, motorb, sensora, sensorb);
			}
		}

	}

	private static void turn(NXTRegulatedMotor motora, NXTRegulatedMotor motorb) {
		motorb.setSpeed(360);
		motora.setSpeed(0);

		motorb.backward();
		Delay.msDelay(25000);
	}

	private static void synchronize(NXTRegulatedMotor motora,
			NXTRegulatedMotor motorb, TouchSensor sensora, TouchSensor sensorb) {
		motora.setSpeed(180);
		motorb.setSpeed(180);
		while (!sensora.isPressed() && Button.ESCAPE.isUp()) {
			motora.forward();
		}
		motora.stop();
		while (!sensorb.isPressed() && Button.ESCAPE.isUp()) {
			motorb.forward();
		}
		motorb.stop();
	}

	private static void initWalk(NXTRegulatedMotor motora,
			NXTRegulatedMotor motorb, TouchSensor sensora, TouchSensor sensorb) {
		synchronize(motora, motorb, sensora, sensorb);
		motorb.rotate(540);
	}
}