Coding my sunspension Need HELP PLS

I am trying to make sunspension for box applaying force back if box to close to ground but it dosent work can anyone help, you can test this on box just add script and just // tmA and text rendering stuff or add 4 childs whit text render PTA PTB PTC PTD

using UnityEngine; using System.Collections;

 public class ReycastingSuspension : MonoBehaviour {
 //The distance of ray
 public float RaycastDistance;
 //Variable to play whit in unity editor
 public float SunspensionPower;
    
 // Use this for initialization
 void Start () {
 }
  
 // Update is called once per frame
 void Update ()
 {
  
     //Difines botom corners so thet can later be used for raycasting
     Vector3 pointA = transform.TransformPoint (new Vector3 (0.5f, -0.5f, 0.5f));
     Vector3 pointB = transform.TransformPoint (new Vector3 (0.5f, -0.5f, -0.5f));
     Vector3 pointC = transform.TransformPoint (new Vector3 (-0.5f, -0.5f, 0.5f));
     Vector3 pointD = transform.TransformPoint (new Vector3 (-0.5f, -0.5f, -0.5f));
     TextMesh tmA = (TextMesh)GameObject.Find("PTA").GetComponent<TextMesh>();
     TextMesh tmB = (TextMesh)GameObject.Find("PTB").GetComponent<TextMesh>();
     TextMesh tmC = (TextMesh)GameObject.Find("PTC").GetComponent<TextMesh>();
     TextMesh tmD = (TextMesh)GameObject.Find("PTD").GetComponent<TextMesh>();
                
                 //defines HitColector and executes ray for PointA
                 RaycastHit hitColectorPointA;
                 if (Physics.Raycast (pointA, -transform.up, out hitColectorPointA, RaycastDistance)) {
  
                         //CRatio shoud be formula for how much ray is compresed
                         float CRatioA =hitColectorPointA.distance / RaycastDistance;
  
                         //Add UP force at point to lift thet side if its lower by any other force
                         rigidbody.AddForceAtPosition (Vector3.up * CRatioA * SunspensionPower, pointA, ForceMode.Force);
  
                         // GreenRay if hiting somthing      
                         Debug.DrawRay (pointA, -transform.up * RaycastDistance, Color.green);
                         //Debug.Log (hitColectorPointA.distance);
                         var hitdisA = hitColectorPointA.distance;
                         string RounderA = string.Format("{0:0.##}", hitdisA);
                         tmA.text  = RounderA;
                        
                 } else
                 {
                         //Red Ray if not hiting anything
                         Debug.DrawRay (pointA, -transform.up * RaycastDistance, Color.red);
                 }  
        
        
                 //defines HitColector and executes ray for PointB
                 RaycastHit hitColectorPointB;
                 if (Physics.Raycast (pointB, -transform.up, out hitColectorPointB, RaycastDistance)) {
  
                         //CRatio shoud be formula for how much ray is compresed
                         float CRatioB =hitColectorPointB.distance / RaycastDistance;
  
                         //Add UP force at point to lift thet side if its lower by any other force
                         rigidbody.AddForceAtPosition (Vector3.up * CRatioB * SunspensionPower, pointB, ForceMode.Force);
  
                         // GreenRay if hiting somthing      
                         Debug.DrawRay (pointB, -transform.up * RaycastDistance, Color.green);
                         //Debug.Log (hitColectorPointB.distance);
                         var hitdisB = hitColectorPointA.distance;
                         string RounderB = string.Format("{0:0.##}", hitdisB);
                         tmB.text  = RounderB;
                 } else
                 {
                         //Red Ray if not hiting anything
                         Debug.DrawRay (pointB, -transform.up * RaycastDistance, Color.red);
            
                 }
        
  
  
                 //defines HitColector and executes ray for PointC
                 RaycastHit hitColectorPointC;
                 if (Physics.Raycast (pointC, -transform.up, out hitColectorPointC, RaycastDistance)) {  
  
                         //CRatio shoud be formula for how much ray is compresed
                         float CRatioC = hitColectorPointC.distance / RaycastDistance;
  
                         //Add UP force at point to lift thet side if its lower by any other force
                         rigidbody.AddForceAtPosition (Vector3.up * CRatioC * SunspensionPower, pointC, ForceMode.Force);
  
                         // GreenRay if hiting somthing      
                         Debug.DrawRay (pointC, -transform.up * RaycastDistance, Color.green);
                         //Debug.Log (hitColectorPointC.distance);
                         var hitdisC = hitColectorPointC.distance;
                         string RounderC = string.Format("{0:0.##}", hitdisC);
                         tmC.text  = RounderC;
                 } else
                 {
                         //Red Ray if not hiting anything
                         Debug.DrawRay (pointC, -transform.up * RaycastDistance, Color.red);
                 }
        
  
  
                 //defines HitColector and executes ray for PointD
                 RaycastHit hitColectorPointD;
                 if (Physics.Raycast (pointD, -transform.up, out hitColectorPointD, RaycastDistance)) {  
  
                         //CRatio shoud be formula for how much ray is compresed
                         float CRatioD = (hitColectorPointD.distance / RaycastDistance);
                        
                         //Add UP force at point to lift thet side if its lower by any other force
                         rigidbody.AddForceAtPosition (Vector3.up * CRatioD * SunspensionPower, pointD, ForceMode.Force);
  
                         // GreenRay if hiting somthing      
                         Debug.DrawRay (pointD, -transform.up * RaycastDistance, Color.green);
                         //Debug.Log (hitColectorPointD.distance);
                         var hitdisD = hitColectorPointD.distance;
                         string RounderD = string.Format("{0:0.##}", hitdisD);
                         tmD.text  = RounderD;
                 } else
                 {
                         //Red Ray if not hiting anything
                         Debug.DrawRay (pointD, -transform.up * RaycastDistance, Color.red);
                 }  
             }
         }