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How to increase the speed of a motor when the joystick is move in the forward position.(first robotics blocks/java)

I am in FIRST ROBOTICS and trying to get the motors on my robots to move faster than they currently are. At the moment, the wheels move fairly slow and we want them to move faster by increasing the motor speed based on the positive and negative position of the stick.
Here is our original code, which works but does not move faster:
`
package org.firstinspires.ftc.teamcode;
import com.qualcomm.robotcore.eventloop.opmode.LinearOpMode;
import com.qualcomm.robotcore.eventloop.opmode.TeleOp;
import com.qualcomm.robotcore.hardware.DcMotor;
#TeleOp(name = "v221 (Blocks to Java)")
public class v221 extends LinearOpMode {
private DcMotor Back_Right;
private DcMotor Back_Left;
private DcMotor Front_Right;
private DcMotor Front_Left;
/**
* This function is executed when this Op Mode is selected from the Driver Station.
*/
#Override
public void runOpMode() {
float Back_Right2;
float Back_Left2;
float Front_Right2;
float Front_Left2;
Back_Right = hardwareMap.get(DcMotor.class, "Back_Right");
Back_Left = hardwareMap.get(DcMotor.class, "Back_Left");
Front_Right = hardwareMap.get(DcMotor.class, "Front_Right");
Front_Left = hardwareMap.get(DcMotor.class, "Front_Left");
// put initizalion blocks here
waitForStart();
if (opModeIsActive()) {
// Put run blocks here.
while (opModeIsActive()) {
// Put loop blocks here.
Back_Right2 = gamepad1.right_stick_y;
Back_Right.setPower(Back_Right2);
telemetry.addData("rightWheelpwr", Back_Right2);
Back_Left2 = -gamepad1.left_stick_y;
Back_Left.setPower(Back_Left2);
telemetry.addData("leftWheelpwr", Back_Left2);
Front_Right2 = -gamepad1.right_stick_y;
Front_Right.setPower(Front_Right2);
telemetry.addData("rightWheelpwr", Front_Right2);
Front_Left2 = -gamepad1.left_stick_y;
Front_Left.setPower(Front_Left2);
telemetry.addData("leftWheelpwr", Front_Left2);
}
}
}
}
Here is the code we made to try and make it faster:
package org.firstinspires.ftc.teamcode;
import com.qualcomm.robotcore.eventloop.opmode.LinearOpMode;
import com.qualcomm.robotcore.eventloop.opmode.TeleOp;
import com.qualcomm.robotcore.hardware.DcMotor;
#TeleOp(name = "v2215 (Blocks to Java)")
public class v2215 extends LinearOpMode {
private DcMotor Back_Right;
private DcMotor Back_Left;
private DcMotor Front_Right;
private DcMotor Front_Left;
/**
* This function is executed when this Op Mode is selected from the Driver Station.
*/
#Override
public void runOpMode() {
float Back_Right2;
float Back_Left2;
float Front_Right2;
float Front_Left2;
Back_Right = hardwareMap.get(DcMotor.class, "Back_Right");
Back_Left = hardwareMap.get(DcMotor.class, "Back_Left");
Front_Right = hardwareMap.get(DcMotor.class, "Front_Right");
Front_Left = hardwareMap.get(DcMotor.class, "Front_Left");
// put initizalion blocks here
waitForStart();
if (opModeIsActive()) {
// Put run blocks here.
while (opModeIsActive()) {
// Put loop blocks here.
Back_Right2 = gamepad1.right_stick_y;
Back_Right.setPower(Back_Right2);
telemetry.addData("rightWheelpwr", Back_Right2 * 5);
Back_Left2 = -gamepad1.left_stick_y;
Back_Left.setPower(Back_Left2);
telemetry.addData("leftWheelpwr", Back_Left2);
Front_Right2 = -gamepad1.right_stick_y;
Front_Right.setPower(Front_Right2);
telemetry.addData("rightWheelpwr", Front_Right2);
Front_Left2 = -gamepad1.left_stick_y;
Front_Left.setPower(Front_Left2);
telemetry.addData("leftWheelpwr", Front_Left2);
}
}
}
}
If you know how to make it faster, please let us know.
Multiplying the power input to the motor by adding a multiplier - Expected it to multiply how far you pushed the stick by the power given to the motor.
We did more of course, but can't think of them to add

Static methods in greenfoot

So for my class I have to use the Greenfoot IDE. And my goal is to:
“the pig eats all the mushrooms currently in the barrel”
The pig will have to call the barrel’s getMushroom() method to find out how many mushrooms the barrel currently stores. The pig can add this amount to its count of mushrooms eaten. Remember, the mushrooms are already gone from the world - this happened when the barrel “stored them.”
However if I try and go into the Pig class and use Barrel.getMushrooms(); it says non-static method getMushrooms() cannot be referenced from a static context.
But when I try using stuff like
Barrel b1 = new Barrel();
b1.getMushrooms();
My counter with shrooms never works out right..
Class Barrel
import greenfoot.*; // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)
import java.util.List;
/**
* Write a description of class Barrel here.
*
* #author (your name)
* #version (a version number or a date)
*/
public class Barrel extends Actor
{
private final double SCALE_FACTOR_5 = 1.05;
private final double SCALE_FACTOR_25 = 1.25;
public int mushroomsStored;
private int ns;
public Barrel() {
mushroomsStored = 0;
ns = 0;
}
/**
* Main method of Barrel
*/
public void act() {
followMouse();
storeMushrooms();
reset();
}
/**
* Follows mouse drag-and-drop motion.
*/
public void followMouse() {
if(Greenfoot.mouseDragged(this)) {
MouseInfo mouse = Greenfoot.getMouseInfo();
setLocation(mouse.getX(), mouse.getY());
}
}
/**
* Eats nearby mushrooms when dropped.
* Increases its current image scale by 5% when it eats one mushroom.
* Increases its current image scale by 25% when it eats five mushrooms.
* If this barrel stores more than 10 mushrooms, this barrel has itself removed from
* this world.
*/
public void storeMushrooms() {
if(Greenfoot.mouseDragEnded(this)) {
List<Mushroom> nearby = getObjectsInRange(75, Mushroom.class);
ns = nearby.size();
for(Mushroom m : nearby) {
getWorld().removeObject(m);
mushroomsStored++;
}
if(ns < 5 ) {
GreenfootImage img = getImage();
int width = (int)(img.getWidth() * SCALE_FACTOR_5);
int height = (int)(img.getHeight() * SCALE_FACTOR_5);
img.scale(width, height);
}
if (ns >= 5) {
GreenfootImage img = getImage();
int width = (int)(img.getWidth() * SCALE_FACTOR_25);
int height = (int)(img.getHeight() * SCALE_FACTOR_25);
img.scale(width, height);
}
if(mushroomsStored == 10) {
getWorld().removeObject(this);
}
}
}
/**
* Returns this barrel to its original (x,y) location and its
* original image scale.
*/
public void reset() {
if(Greenfoot.mouseClicked(this)) {
MouseInfo mouse = Greenfoot.getMouseInfo();
if(mouse.getButton() == 3) {
this.setLocation(565, 350);
setImage(new GreenfootImage("barrel.png"));
mushroomsStored = 0;
}
}
}
/**
* Returns how many mushrooms this barrel has stored.
*/
public int getMushrooms() {
return mushroomsStored;
}
/**
* Automatically called by Greenfoot whenever a Barrel object
* is placed in a world. In this assigment, we use it to remember
* the initial state of this barrel - its (x,y) position and its
* original image size.
*/
public void addedToWorld(World world) {
GreenfootImage img = new GreenfootImage("barrel.png");
setImage(img);
final int originalX = getX();
final int originalY = getY();
final int originalWidth = img.getWidth();
final int originalHeight = img.getHeight();
}
}
Class Pig
import greenfoot.*; // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)
/**
* Write a description of class Pig here.
*
* #author (your name)
* #version (a version number or a date)
*/
public class Pig extends Actor
{
/** Keeps track of how many mushrooms this pig has eaten. */
private int shrooms;
/**
* Constructs a Pig object and initializes it as having
* eaten no mushrooms.
*/
public Pig() {
shrooms = 0;
}
/**
* Follows the mouse movement and eats mushrooms on mouse clicks.
* Stops the scenario once this pig has eaten at least 15 mushrooms.
*/
public void act()
{
followMouse();
eatMushrooms();
getMS();
}
public void getMS() {
b
}
public void followMouse() {
if (Greenfoot.mouseMoved(null)) {
MouseInfo mouse = Greenfoot.getMouseInfo();
setLocation(mouse.getX(), mouse.getY());
}
}
public void eatMushrooms() {
if (Greenfoot.mouseClicked(null)) {
Mushroom m = (Mushroom) getOneIntersectingObject(Mushroom.class);
if (m != null) {
shrooms++;
getWorld().removeObject(m);
}
}
if (shrooms > 29) {
Greenfoot.stop();
}
}
}

Your pig needs a reference to the barrel class. Typically in Greenfoot, class A gets a reference to class B in one of two ways:
Class A is passed the reference to B on creation. This is typical if B creates A: for example if a gun fires bullets, the gun passes a gun reference to the bullet.
Class A collides with class B, for example your player character runs into a collectable, or an enemy collides with your player.
I'm not certain, but I suspect you fall under case 2, in which case you want to use:
Barrel b = (Barrel)getOneIntersectingObject(Barrel.class);
The b variable will be null when you're not touching a barrel, and otherwise it will be a Barrel object which you can call methods on.

When calling the method with the class name like
Barril.getMushrooms()
Your method should be coupled to your class and not an instance. How would you do that? By making it a static method.
I assume that you want to have an instance method used in this context so the right way to do it is the one you presented :
Barril b = new Barril();
b.getMushrooms();
But think about it. What is the value of mushroomsStored if you just created your object?
... You guessed it. You did not even initialized it so it will return the value by default : 0

Calling a method from JFrame from another class

I am currently making a terrain generator, everything works fine in one class but I am going to be expanding my application.
Currently I have a JFrame class which holds everything, generating the terrain, painting the terrain, finding locations etc.
I want to add another class that will generate the terrain but when I create this class I need to access fields from the main JFrame class and when I do I get a stack overflow error - here is my code.
public class Simulator extends Applet
{
//fields
public Simulator()
{
grid = new int[100][100];
inhabGrid = new boolean[grid.length][grid.length];
gridSize = grid.length - 1;
dist = grid.length;
TerrainGenerator gen = new TerrainGenerator();
setSize(dist,dist);
seedGrid();
findInhabLocation();
printGridToConsole();
}
public void paint(Graphics g)
{
//panting the grid
}
public void seedGrid()
{
//seeding
}
public boolean generateTerrain(int x1,int y1, int x2, int y2)
{
//terrain generator
}
public boolean mouseUp(Event evt, int x, int y)
{
seedGrid(); //Create a new map
findInhabLocation();
repaint();
printGridToConsole();
return true;
}
public boolean keyEvents(Event evt, int x, int y)
{
seedGrid(); //Create a new map
findInhabLocation();
repaint();
printGridToConsole();
return true;
}
public void findInhabLocation()
{
//find best inhabitant location
}
public int locateWater(int x, int y)
{
//finding closest water
}
public int locateJungle(int x, int y)
{
//finding closest jungle
}
}
}
That works fine in its own class but when I create a class for example:
public class TerrainGenerator
{
Simulator sim = new Simulator();
}
I know this has something to do with the constructor and it's something silly I am doing, what would be the best way of splitting up this app into classes, for example terrain generator, inhabitants etc
For example I want to be able to call a method from the 'TerrainGenerator' class and call i.e. terrainGenerator.generateTerrain

Your TerrainGenerator creates a Simulator object and vice versa, hence you'll end up with infinitely many objects (but at some point the stack is full and a stack overflow exception is thrown instead...)
Instead of creating a new Simulator in your TerrainGenerator, you should pass a reference to your current Simulator (well, actually, that is not a great design either, but I'm not gonna confuse you with the problems of circular references).

Heuster answer is correct, furthermore, I think you could take look at MVC to help you organize your classes.

Depending which should be the parent, you can pass in the instantiated class to the other, ie;
private final TerrainGenerator gen; //if you need to save this.
public Simulator(TerrainGenerator terrainGenerator)
{
this.gen = terrainGenerator;
....etc
}
public class TerrainGenerator
{
Simulator sim = new Simulator(this);
}
or
private final TerrainGenerator gen; //if you need to save this.
public Simulator()
{
this.gen = new TerrainGenerator(this);
....etc
}
private final Simulator sim; //If you need to save it.
public class TerrainGenerator
{
public TerrainGenerator(Simulator simulator) {
this.sim = simulator;
}
}

Accessing values from another thread

My question is: How do I access values from another thread?
I have two .java files, Main.java and TrackHands.java
Main.java
/**
* This is the main class, it is used to start the program. The only use of this
* is to make everything more organized.
*/
package Kinect;
//import processing.core.PApplet;
/**
* #author Tony Nguyen <Tony.Nguyen#HvA.nl>
*
*/
public class Main
{
public static void main(String _args[])
{
Thread trackHands = new Thread(new TrackHands());
trackHands.start();
}
}
TrackHands.java
/*
* This uses the normal Java layout to track the user and prints out the coordinates of the left and right hand
*/
package Kinect;
import SimpleOpenNI.*;
import processing.core.PApplet;
import processing.core.PVector;
/**
* #author Tony Nguyen <Tony.Nguyen#HvA.nl>
* #version 1.0
*/
public class TrackHands extends PApplet implements Runnable
{
private int handLeftX, handLeftY = 0; // Holds the coordinates of the left hand
SimpleOpenNI kinect = new SimpleOpenNI(this); // kinect object
/**
* Constructor Takes no parameters
*/
public TrackHands()
{
}
/**
* run This will be executed when the thread starts
*/
#Override
public void run()
{
IntVector userList = new IntVector(); // Make a vector of ints to store the list of users
PVector leftHand = new PVector(); // Make a vector to store the left hand
PVector convertedLeftHand = new PVector();
kinect.enableDepth();
kinect.enableUser(SimpleOpenNI.SKEL_PROFILE_ALL);
kinect.setMirror(true);
while (true)
{
kinect.update();
kinect.getUsers(userList); // Write the list of detected users into the vector
if (userList.size() > 0) // Checks if a user is found
{
int userId = userList.get(0); // Get first user
if (kinect.isTrackingSkeleton(userId)) // If successfully calibrated
{
kinect.getJointPositionSkeleton(userId,
SimpleOpenNI.SKEL_LEFT_HAND, leftHand); // Put the position of the left hand into that vector
kinect.convertRealWorldToProjective(leftHand,
convertedLeftHand);
this.handLeftX = round(convertedLeftHand.x);
this.handLeftY = round(convertedLeftHand.y);
}
}
}
}
// User-tracking callbacks!
public void onNewUser(int userId)
{
System.out.println("Start pose detection");
kinect.startPoseDetection("Psi", userId);
}
public void onEndCalibration(int userId, boolean successful)
{
if (successful)
{
System.out.println(" User calibrated !!!");
kinect.startTrackingSkeleton(userId);
} else
{
System.out.println(" Failed to calibrate user !!!");
kinect.startPoseDetection("Psi", userId);
}
}
public void onStartPose(String pose, int userId)
{
System.out.println("Started pose for user");
kinect.stopPoseDetection(userId);
kinect.requestCalibrationSkeleton(userId, true);
}
}
I have tried to use a getter and a setter to get the values from TrackHands.java into another thread.
Tried creating objects and passing the values as parameters, but then my program will not use these new values in the run() method.

To get values from TrackHands, use a get method that accesses an instance variable that is set in run()
class TrackHands {
Object output;
public void run() {
while(true) {
output = new Object();
}
}
public Object getOutput() {
return output;
}
}
Pass TrackHands into your consumer object and use it to call get getOutput() method.
Passing values in is a bit trickier, because you might cause race condition. Try something like this
class TrackHands {
Object input = null;
public boolean setInput(Object input) {
if(this.input == null) {
this.input = input;
return true;
} else {
return false;
}
}
}
When your run() method uses input, set it to null so that another thread can pass in another input. Your producer thread will use this loop to pass in input:
public void sendInput(TrackHands th, Object input) {
boolean done = false;
while(!done) {
done = th.setInput(input);
}
}
This will keep trying to pass in input until it succeeds.
setInput uses the synchronized keyword so that only one thread can call this method at once, otherwise you'll get a race condition.

A friend of mine solved my problem.
I want to thank everyone for helping me!
Main.java
/**
* This is the main class, it is used to start the program. The only use of this
* is to make everything more organized.
*/
package Kinect;
//import processing.core.PApplet;
/**
* #author Tony Nguyen <Tony.Nguyen#HvA.nl>
*
*/
public class Main
{
public static void main(String _args[])
{
// PApplet.main(new String[]
// {
// Sensor.class.getName()
// });
ValueStore valueStore = new ValueStore(); // ADDED THIS LINE
Thread trackHands = new Thread(new TrackHands(valueStore)); // ADDED THIS LINE
trackHands.start();
}
}
TrackHands.java
/*
* This uses the normal Java layout to track the user and prints out the coordinates of the left and right hand
*/
package Kinect;
import SimpleOpenNI.*;
import processing.core.PApplet;
import processing.core.PVector;
/**
* #author Tony Nguyen <Tony.Nguyen#HvA.nl>
* #version 1.0
*/
public class TrackHands extends PApplet implements Runnable
{
private int handLeftX, handLeftY, handRightX, handRightY = 0; // Holds the coordinates of the left hand
SimpleOpenNI kinect = new SimpleOpenNI(this); // kinect object
private ValueStore valuesStore; // ADDED THIS LINE
/**
* Constructor Takes no parameters
*/
public TrackHands()
{
}
public TrackHands(ValueStore valuesStore)
{
this.valuesStore = valuesStore;
}
/**
* run This will be executed when the thread starts
*/
#Override
public void run()
{
IntVector userList = new IntVector(); // Make a vector of ints to store the list of users
PVector leftHand = new PVector(); // Make a vector to store the left hand
PVector rightHand = new PVector(); // Make a vector to store the right hand
PVector convertedLeftHand = new PVector(); // Make a vector to store the actual left hand
PVector convertedRightHand = new PVector(); // Make a vector to store the actual right hand
kinect.enableDepth();
kinect.enableUser(SimpleOpenNI.SKEL_PROFILE_ALL);
kinect.setMirror(true);
while (true)
{
kinect.update();
kinect.getUsers(userList); // Write the list of detected users into the vector
if (userList.size() > 0) // Checks if a user is found
{
int userId = userList.get(0); // Get first user
if (kinect.isTrackingSkeleton(userId)) // If successfully calibrated
{
kinect.getJointPositionSkeleton(userId,
SimpleOpenNI.SKEL_LEFT_HAND, leftHand); // Put the position of the left hand into that vector
kinect.getJointPositionSkeleton(userId,
SimpleOpenNI.SKEL_RIGHT_HAND, rightHand); // Put the position of the left hand into that vector
kinect.convertRealWorldToProjective(leftHand,
convertedLeftHand);
kinect.convertRealWorldToProjective(rightHand,
convertedRightHand);
this.handLeftX = round(convertedLeftHand.x);
this.handLeftY = round(convertedLeftHand.y);
this.handRightX = round(convertedRightHand.x);
this.handRightY = round(convertedRightHand.y);
valuesStore.setHandValues(handLeftX, handLeftY, handRightX, handRightY); // ADDED THIS LINE
}
}
}
}
// User-tracking callbacks!
public void onNewUser(int userId)
{
System.out.println("Start pose detection");
kinect.startPoseDetection("Psi", userId);
}
public void onEndCalibration(int userId, boolean successful)
{
if (successful)
{
System.out.println(" User calibrated !!!");
kinect.startTrackingSkeleton(userId);
} else
{
System.out.println(" Failed to calibrate user !!!");
kinect.startPoseDetection("Psi", userId);
}
}
public void onStartPose(String pose, int userId)
{
System.out.println("Started pose for user");
kinect.stopPoseDetection(userId);
kinect.requestCalibrationSkeleton(userId, true);
}
}
Then added a class to store the values so another class can access it.
ValueStore.java
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package Kinect;
/**
*
* #author Tony Nguyen <Tony.Nguyen#HvA.nl>
*/
public class ValueStore
{
private int leftX, leftY, rightX, rightY = 0;
public void setHandValues(int leftX, int leftY, int rightX, int rightY)
{
this.leftX = leftX;
this.leftY = leftY;
this.rightX = rightX;
this.rightY = rightY;
}
public int getLeftX()
{
return this.leftX;
}
}

JBox2D Body Was There, Now it's null?

A strange bug I can't track down. I've implemented a ContactListener class for handling collisions in my Android game. In the beginContact(Contact arg0) method I can see that the two bodies in arg0 is there, and pushed onto a stack. Right after calling world.step() I run my own handleCollisions() method, where I pop off the Contact objects and do some game logic. However, occasionally when I pop off a Contact, one or both of its bodies are null.
The Contact goes in the stack with its bodies there, but it comes out with null bodies. I don't know why this is occurring, and more importantly, I can't find when this is occurring. To my knowledge, none of my code elsewhere is removing the bodies, but then again there could be side effects I'm unaware of. It doesn't help that this doesn't always happen. Typically it occurs when there's several collisions occurring.
Anyone have any ideas on what might remove the bodies? Or, does anyone know of a way to track the bodies to determine when they become null?
Below is some code which may or may not be helpful:
public class ConcreteContactListener implements ContactListener
{
private Stack<Contact> contacts;
public ConcreteContactListener()
{
contacts = new Stack<Contact>();
}
#Override
public void beginContact(Contact arg0)
{
contacts.push(arg0);
System.out.println("push: " + arg0.m_fixtureA.m_body);
}
public int handleCollisions(ArrayList<Ball> balls, World world, ArrayList<Ball> smears, SoundEffects sfx, Combos combos)
{
int score = 0;
while (!contacts.isEmpty())
{
Contact contact = contacts.pop();
System.out.println("Contact: " + contact.m_fixtureA.m_body);
int a = -1;
int b = -1;
for (int i = 0; i < balls.size(); i++)
{
System.out.println("Ball: " + balls.get(i).getBody());
if (contact.m_fixtureA.m_body.equals(balls.get(i).getBody()))
a = i;
else if (contact.m_fixtureB.m_body.equals(balls.get(i).getBody()))
b = i;
}
...
}
}

Contacts are pooled and re-used, so I would not recommend using this approach. Instead I would buffer only the information you need (which is probably the two bodies). The jbox2d testbed handles it this way:
First we have a contact point:
public class ContactPoint {
public Fixture fixtureA;
public Fixture fixtureB;
public final Vec2 normal = new Vec2();
public final Vec2 position = new Vec2();
public PointState state;
}
And then we listen like so:
public void beginContact(Contact contact) {
}
public void endContact(Contact contact) {
}
public void postSolve(Contact contact, ContactImpulse impulse) {
}
private final PointState[] state1 = new PointState[Settings.maxManifoldPoints];
private final PointState[] state2 = new PointState[Settings.maxManifoldPoints];
private final WorldManifold worldManifold = new WorldManifold();
public void preSolve(Contact contact, Manifold oldManifold) {
Manifold manifold = contact.getManifold();
if (manifold.pointCount == 0) {
return;
}
Fixture fixtureA = contact.getFixtureA();
Fixture fixtureB = contact.getFixtureB();
Collision.getPointStates(state1, state2, oldManifold, manifold);
contact.getWorldManifold(worldManifold);
for (int i = 0; i < manifold.pointCount
&& pointCount < MAX_CONTACT_POINTS; i++) {
ContactPoint cp = points[pointCount];
cp.fixtureA = fixtureA;
cp.fixtureB = fixtureB;
cp.position.set(worldManifold.points[i]);
cp.normal.set(worldManifold.normal);
cp.state = state2[i];
++pointCount;
}
}
This would probably be a bit overkill for your purposes, as it executes this logic for every single contact. Instead you can use the beginContact() and endContact() methods and buffer something a little more optimized with your game, like just storing the colliding bodies or something.