The Rigidbody2D attached to the Joint2D.
Joint2D are automatically attached to a Rigidbody2D on the same GameObject as the Joint2D.
Additional resources: Rigidbody2D.
using UnityEngine; using System.Collections;
public class ExampleClass : MonoBehaviour { public Vector2 force = Vector2.up;
void Start() { // Apply a force to the rigidbody attached to the joint. GetComponent<Joint2D>().attachedRigidbody.AddForce(force); } }