Connect hingejoint with collision object

I'm making a 2d game where you can connect objects by a rope, but i have a problem with the rope that needs to attach two object to each other. I created a rope with two hinge joints, one left that needs to connect one object and one right that needs to connect to the other object that collides. How can I set the connectbody of the hingejoint with the rigidbody of the collided object?

this is my code for now. It's not complete, I want to set the rigidbody of the collision objects to krat1 and krat2.

 using UnityEngine;
 using System.Collections;
 
 public class ropeScript : MonoBehaviour {
     private HingeJoint2D joint1;
     private HingeJoint2D joint2;
     private Rigidbody2D krat1;
     private Rigidbody2D krat2;
     private bool hingeTrue;
 
     // Use this for initialization
     void Start () {
         hingeTrue = true;
         print(hingeTrue);
 
 
     }
     void OnCollisionEnter (Collision col)
     {
         
 
         
     }
     // Update is called once per frame
     void Update () {
 
         hinge();
     }
     public void hinge () {
     if(Time.timeScale==1 & hingeTrue) {
             print("it's true");
         joint1 = gameObject.AddComponent<HingeJoint2D>();
         joint2 = gameObject.AddComponent<HingeJoint2D>();
         krat1 = krat1.GetComponent<Rigidbody2D>();
         krat2 =    krat2.GetComponent<Rigidbody2D>();
         joint1.connectedAnchor = new Vector2(3.7f, 0 );
         joint2.connectedAnchor = new Vector2(-3.7f, 0);
 
         joint1.connectedBody = krat1;
         joint2.connectedBody = krat2;
 
         hingeTrue = false;
     }
     }
 
 }