Published November 18, 2016 © GPL3+

AR Drone with a little Java

This project allows you to control an AR Parrot Drone with Java software.

IntermediateShowcase (no instructions)2 hours6,181

Things used in this project

Hardware components

Parrot AR.Drone

Story

Overview

I discovered that there was an open source software package that allows users to create Java applications to control the AR Parrot drones. The API is called Autonomous4J and can be located here. The AR drones have their own wireless access point and I essentially used my computer to connect to WiFi signal. Once a connection was established, the software will control any action the drone is capable of including flight directions, LED control, and recording.

How to do it

Here's a brief run down of the steps to get up and running:

1) Have a computer with Java installed.

2) Ensure that the Autonomous4J libraries are on the classpath for your application.

3) Code your application.

4) Make sure your computer/device is connected to the WAP signal for the AR Drone.

5) Execute your application.

6) Have some Java!

The project in action

Here is a video of the project in action:

Code

package drone;

public class demo {

    
    public static void main(String[] args) {
        performDemo(new Brain());
    }

    
    private static void performDemo(Brain br) {

        //Attempt to connect to the drone
        if (br.connect()) {
            try {

                //Execute drone commands
                commands(br);

            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                br.disconnect();
            }

        } else {
            System.out.println("No Drone Connection.");
        }

    }

    private static void commands(Brain br) {

        br.takeoff().hold(3000);
        br.stay().hold(3000);
        br.land();
    }

}

package drone;

import java.util.List;

import org.autonomous4j.interfaces.A4jBrain;
import org.autonomous4j.listeners.xyz.A4jErrorListener;
import org.autonomous4j.listeners.xyz.A4jNavDataListener;
import org.autonomous4j.listeners.xyz.A4jReadyStateChangeListener;
import org.autonomous4j.tracking.A4jBlackBox;
import org.autonomous4j.tracking.A4jBlackBox.Movement;

import com.dronecontrol.droneapi.DroneController;
import com.dronecontrol.droneapi.ParrotDroneController;
import com.dronecontrol.droneapi.commands.composed.PlayLedAnimationCommand;
import com.dronecontrol.droneapi.data.Config;
import com.dronecontrol.droneapi.data.enums.LedAnimation;

public class Brain implements A4jBrain {

    private Config cfg;
    private DroneController controller;
    private final A4jBlackBox recorder;
    private boolean isRecording;
    
    public Brain() {
        cfg = new Config("ProtoDrone", "profile", 1);
        this.recorder = new A4jBlackBox();
        isRecording = true;
    }
    
    @Override
    public boolean connect() {
        return connectToDrone("192.168.1.1");
    }

    public boolean connectToDrone(String ipAddress) {
        try {
            controller = ParrotDroneController.build();
            controller.start(cfg);

            controller.addNavDataListener(new A4jNavDataListener());    
            controller.addReadyStateChangeListener(new A4jReadyStateChangeListener());
            controller.addErrorListener(new A4jErrorListener());
        } catch (Exception ex) {
            System.err.println("Exception creating new drone connection: " + ex.getMessage());
            return false;
        }
        return true;
    }
    
    
    @Override
    public void disconnect() {
        if (controller != null) {
            controller.stop();
        }
        recorder.shutdown();
    }

    @Override
    public A4jBrain doFor(long ms) {
        return hold(ms);
    }

    @Override
    public A4jBrain hold(long ms) {
        System.out.println("Hold for " + ms + " milliseconds...");
        try {
            Thread.sleep(ms);
            if (isRecording) {
                recorder.recordDuration(ms);
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        
        return this;
    }

    @Override
    public A4jBrain stay() {
        return hover();
    }
    
    private A4jBrain hover() {
        System.out.println("--Hover--");
        controller.move(0, 0, 0, 0);
        if (isRecording) {
            recorder.recordAction(A4jBlackBox.Action.STAY);
        }
        
        return this;
    }

    @Override
    public A4jBrain goHome() {
        processRecordedMovements(recorder.home());
        return this;
    }

    @Override
    public A4jBrain replay() {
        processRecordedMovements(recorder.getRecording());
        return this;
    }

    @Override
    public void processRecordedMovements(List<Movement> moves) {
        // Disable recording for playback
        isRecording = false;

        for (Movement curMov : moves) {
            switch(curMov.getAction()) {
                case FORWARD:
                    forward(curMov.getSpeed());
                    break;
                case BACKWARD:
                    backward(curMov.getSpeed());
                    break;
                case RIGHT:
                    goRight(curMov.getSpeed());
                    break;
                case LEFT:
                    goLeft(curMov.getSpeed());
                    break;
                case UP:
                    up(curMov.getSpeed());
                    break;
                case DOWN:
                    down(curMov.getSpeed());
                    break;
                case STAY:
                    stay();
                    break;
                case TAKEOFF:
                    takeoff();
                    break;
                case LAND:
                    land();
                    break;
                case LIGHTS:
                    playLedAnimation(curMov.getSpeed(), (int) curMov.getDuration()/1000);
                    break;
            }
            hold(curMov.getDuration());
            System.out.println(curMov);
        }
            
        // Re-enable recording
        isRecording = true;
        
    }
    
    public void land() {
        System.out.println("Land.");
        controller.land();
        if (isRecording) {
            recorder.recordAction(A4jBlackBox.Action.LAND);
        }
    }

    public A4jBrain takeoff() {
        System.out.println("Takeoff!");
        controller.takeOff();
        if (isRecording) {
            recorder.recordAction(A4jBlackBox.Action.TAKEOFF);
        }
        
        return this;
    }
    
    public A4jBrain forward(int speed) {
        System.out.println("Forward @" + speed);
        if (isRecording) {
            recorder.recordAction(A4jBlackBox.Action.FORWARD, speed);
        }
        
        return move(0f, -perc2float(speed), 0f, 0f);
    }

   
    public A4jBrain backward() {
        return backward(100);
    }
    
    public A4jBrain backward(int speed) {
        System.out.println("Backward @" + speed);
        if (isRecording) {
            recorder.recordAction(A4jBlackBox.Action.BACKWARD, speed);
        }

        return move(0f, perc2float(speed), 0f, 0f);
    }
    
    public A4jBrain up() {
        return up(100);
    }

    public A4jBrain up(int speed) {
        System.out.println("up @" + speed);
        if (isRecording) {
            recorder.recordAction(A4jBlackBox.Action.UP, speed);
        }

        return move(0f, 0f, perc2float(speed), 0f);
    }

    public A4jBrain down() {
        return down(100);
    }

    public A4jBrain down(int speed) {
        System.out.println("down @" + speed);
        if (isRecording) {
            recorder.recordAction(A4jBlackBox.Action.DOWN, speed);
        }

        return move(0f, 0f, -perc2float(speed), 0f);
    }

    public A4jBrain goRight(int speed) {
        System.out.println("goRight @" + speed);
        if (isRecording) {
            recorder.recordAction(A4jBlackBox.Action.RIGHT, speed);
        }

        return move(perc2float(speed), 0f, 0f, 0f);
    }

    public A4jBrain goLeft(int speed) {
        System.out.println("goLeft @" + speed);
        if (isRecording) {
            recorder.recordAction(A4jBlackBox.Action.LEFT, speed);
        }

        return move(-perc2float(speed), 0f, 0f, 0f);
    }

    public A4jBrain playLedAnimation(float frequency, int durationSeconds) {
        // "Default" LED animation sequence is blank for now
        playLedAnimation(LedAnimation.BLANK, frequency, durationSeconds);
        return this;
    }
    
    public A4jBrain playLedAnimation(LedAnimation animation, float frequency, int durationSeconds) {
        if (isRecording) {
            recorder.recordAction(A4jBlackBox.Action.LIGHTS, (int) frequency);
        }
        controller.executeCommandsAsync(
                new PlayLedAnimationCommand(cfg.getLoginData(), 
                        animation, frequency, durationSeconds));
        hold(durationSeconds * 1000);
        System.out.println("Blinking " + animation.name() + ", Frequency: " + 
            frequency + " for " + durationSeconds + " seconds.");
        return this;
    }
    
    public A4jBrain move(float roll ,float pitch, float gaz, float yaw) {
        roll = limit(roll, -1f, 1f);
        pitch = limit(pitch, -1f, 1f);
        gaz = limit(gaz, -1f, 1f);
        yaw = limit(yaw, -1f, 1f);
        
        controller.move(roll, pitch, yaw, gaz);
        
        return this;
    }
    
    private float limit(float f, float min, float max) {
        return (f > max ? max : (f < min ? min : f));
    }
    
    private float perc2float(int speed) {
        return (float) (speed / 100.0f);
    }
    

}

Credits

Marcus Johnson

9 projects • 28 followers

Software engineer with professional experience creating, maintaining, integrating, and testing software in Windows and Unix environments.

AR Drone with a little Java

Things used in this project

Hardware components

Story

Overview

How to do it

The project in action

Schematics

AR Drone Connection Diagram

Code

Demo Class

Brain class

Credits

Marcus Johnson

Comments

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AR Drone with a little Java

AR Drone with a little Java

Things used in this project

Hardware components

Story

Overview

How to do it

The project in action

Schematics

AR Drone Connection Diagram

Code

Demo Class

Brain class

Credits

Marcus Johnson

Comments

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