ContactPoint.normal

public Vector3 normal ;

Description

Нормаль к точке контакта.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    void OnCollisionEnter(Collision other) {
        print("Points colliding: " + other.contacts.Length);
        print("First normal of the point that collide: " + other.contacts[0].normal);
    }
}