not proper collision in box2d

问题

I am developing a game in which the user have to hit a high speed ball. To hit the ball I have joined a rectangular body with the actor using revolute joint and enabled its motor, to rotate it with a specified speed(motor speed). Now everything is perfect but sometime when ball`s velocity is high , it is bypassing the rectagular body. Using collision listner i found that collision is happening but ball is not getting reflected after collision. As this is happening only when ball is on a high speed, is it bcoz of density of bodies that are colliding . Or its the motor of revolute joint that is responsible for it ?? Am i missing something here??

Here is the code for both bodies

// method for rectangular body

public Body createRectangleBodyPart(float x, float y, float width,
        float height, short groupIndex) {
    PolygonShape shape = new PolygonShape();
    shape.setAsBox(width*WORLD_TO_BOX, height*WORLD_TO_BOX);
    MassData massData = new MassData();
    massData.mass = 15;
    BodyDef bodyDef = new BodyDef();
    bodyDef.type = BodyType.KinematicBody;
    bodyDef.position.y = y*WORLD_TO_BOX;
    bodyDef.position.x = x*WORLD_TO_BOX;
     body = world.createBody(bodyDef);
    body.setMassData(massData);
    FixtureDef fixtureDef = new FixtureDef();
    fixtureDef.shape = shape;
    fixtureDef.density = 1;
    fixtureDef.friction = 100f;
    fixtureDef.restitution = 0.5f;
    fixtureDef.filter.groupIndex=groupIndex;
    body.createFixture(fixtureDef);
    shape.dispose();
    return body;
}

// method for ball body

    public Body createRoundBodyPart2(float x, float y, float radius,
        short groupIndex, float density, int mass) {

    CircleShape shape = new CircleShape();
    shape.setPosition(new Vector2(0, 0));
    shape.setRadius(radius*WORLD_TO_BOX ); // *18
    BodyDef bodyDef = new BodyDef();
    bodyDef.type = BodyType.DynamicBody;
    bodyDef.position.y = y*WORLD_TO_BOX;
    bodyDef.position.x = x*WORLD_TO_BOX;
    MassData massData = new MassData();
    massData.mass = 8;
    Body body = world.createBody(bodyDef);
    body.setMassData(massData);
    FixtureDef fixtureDef = new FixtureDef();
    fixtureDef.shape = shape;
    fixtureDef.density = 0.5f;
    fixtureDef.restitution=0.007f;
    fixtureDef.filter.groupIndex = groupIndex;
    body.createFixture(fixtureDef);
    shape.dispose();
    return body;
}

回答1:

Try to use isBullet=true property on your ball body

回答2:

Have you tried playing around with these properties: density, friction and restitution.

The ball could be moving so fast that on impact with the rectangular body, the force of the ball is to high for the rec body. Which means that the ball cannot be stopped by the rec body, that why it is passing through it.

Just a guess.

来源：https://stackoverflow.com/questions/16458178/not-proper-collision-in-box2d