this.actor1 = actor1;
this.actor2 = actor2;
// helperActor
ActorParameters actorParameters = new ActorParameters();
actorParameters.setDensity(helperActorDensity);
helperActor = new SphereActor(actorParameters, world, helperActorSize, 0);
CollisionDisabler.disableCollision(world, helperActor);
helperActor.setName(name + "helperActor");
helperActor.setRotation(actor1.getRotation());
helperActor.setPosition(anchor);
helperActor.setMass(helperActorMass);