character jump on collision with a box

hey everyone, i have a character and a box , and what i want is when my character jump and land on the top of the box i want him to jump again without me pressing the 'space bar' ! i want him to jump(just by him self) when he collides with the box , actually im using a bounce script BUT i want him to jump not to bounce ! thanks

here's the bounce script that im using :

 var bounceSpeed = 1.0;
 var bounceAmount = 2.0;
 
 function OnControllerColliderHit(hit: ControllerColliderHit){
 
   if (hit.transform.CompareTag("crate")){
     for (i = 1; i < 2; i++) {
         var t = 0.0;
         while (t < 1.0) {
             t += Time.deltaTime * bounceSpeed;
             transform.position.y = Bounce(t) * bounceAmount;
             yield;
         }
     }
 }
  }
 function Bounce (t : float) : float {
     return Mathf.Sin(Mathf.Clamp01(t) * Mathf.PI);
 }