The Robot under dictate of the LegoMindStorm Java Concurrency API

LET’S SHIFT THETHE WORLD

Miroslav Kopecky

23rd October 2014

MOTIVATION: I HAVE A DREAM

Karel Capek ROBOT

Miroslav Kopecky Prague, 23rd October 2014

© Martin Luther King

CZECH WORD

BEGINNING: HOW IT LOOKED LIKE?


DREAM EVOLUTION


DREAM REDEFINITION

LET’S CREATE/FIND PROBLEMSand try to provide some set of solutions


The Robot under dictate of the LegoMindStorm Java Concurrency API

DO YOU KNOW THE MEANING?


AGENDA:• ROBOT INITIATION SEQUENCE INJAVA SPACE

• PRODUCER / CONSUMER PROBLEM • SYNCHRONIZED (demo) • CONCURRENCY API FEATURE (demo) • CONNECT ALL UNITS TOGETHER (demo)

• ROBOT GOES ONLINE (demo)


ROBOT INITIATION SEQUENCE


LegoMindStorm Java Concurrency APINetwork Communication

Install LeJOS 8.1maven B tool

Compile Libraries (ev3classes)Connect The Brick

(WiFi, Bluetooth,UBS)

EVEN SMALL DREAM IS COMPLEX


EVEN SMALL DREAM IS COMPLEX


RMI

brick = new RemoteEV3(EV3BRICK_IP); brick.setDefault();

…STILL ONE LegoBRICK…

ProdCons

THE ARE some RULEZ again


1. brick.createRegulatedMotor(“A", "M".charAt(0));

2. Port portTouchSensor = brick.getPort("S1"); return new EV3TouchSensor(portTouchSensor);

possible monitor lock

return raw data

3. Mixture of 1 and 2 => IR Sensor (HEAD)

PRODUCER CONSUMER STORY:


BUS - Shared DataStructure

ORDERS PRODUCERS

CONSUMERS ~ BRIDGES

SYNCRONIZED (demo 1, 2, 3) - early age


public EventStorage(){ maxSize = 4; storage = new LinkedList<>(); motorRight = LegoBrickMoveEnginesProvider.

getInstance().getMotorRight(); motorLeft = LegoBrickMoveEnginesProvider.

getInstance().getMotorLeft(); }

feature:: couldn’t extend the lock beyond boundaries

SYNCHRONIZED 1: THREAD CREATION


DEMO

…more threads flying around…

SYNCHRONIZED 2: EXECUTORs


DEMO

… creation and execution…

SYNCHRONIZED 3: LegoExecutor


DEMO

… statistics…

JAVA CONCURENCY API (demo)


couple of synchronisation Utilities: Semaphore, CountDownLatch, CyclicBarrier

Exchanger<List<Integer>> exchanger = new Exchanger<>();

executor.submit( new BrickConsumer( consumerBuffer, exchanger)); executor.shutdown();

EXCHANGER : exchanger.exchange(buffer)


DEMO

CONNECT ALL UNITS TOGETHER (demo)


concurrency and parallelism in the action

1. sensors + engine (front hand) executor.submit(new MoveSimulationSeparate());

2. movement engine (robot platform) executor.submit(new MovementUnit());

CONNECT ALL UNITS TOGETHER


FRONT HAND SYSTEM

PLATFORM

CONNECT ALL UNITS TOGETHER


DEMO

… more treads with statistics…

ROBOT GOES ONLINE (demo)


not to Hollywood (yet) ~ like Frankie => RELAX

1. Spring 4.1 1. JSP + TILES with AngularJS

2. NETTY -> RaspberryPi 3. LegoROBOT

LegoCommandPriorityQueue<E>

ROBOTS GOES ONLINE


DEMO… promising Feature<?>…

QUESTIONS & ANSWERS

I CAN ONLY PLAY THE SOUND!


Audio brickAudio = brick.getAudio(); brickAudio.systemSound(?);

THANKs!


Presentations & Public Speaking

The Robot under dictate of the LegoMindStorm Java Concurrency API