What force is on my object when gravity is off?

Unity Engine
1

As you can see, the farther down my object falls, the more thrashing there is.
What is causing this, once I turn gravity scale to zero?

using UnityEngine;
using System.Collections;

public class PlayerBehavior : MonoBehaviour {
Vector3 jumping;
public int jumpingPower;
float currentY;

// Use this for initialization
void Start () {

}

// Update is called once per frame
void Update () {
ControllerInput ();

}

void ControllerInput()
{
Vector3 move = Vector3.zero;
if (Input.GetKey(KeyCode.D))
move += Vector3.right3;
if (Input.GetKey(KeyCode.A))
move += Vector3.left3;
if (Input.GetKeyDown (KeyCode.Space) jumping.y == 0) {
jumping = (Vector3.up*jumpingPower);
}
if (Input.GetKeyDown (KeyCode.LeftShift)) {
jumping.y = 0;
rigidbody2D.velocity.Set(0, 0);
rigidbody2D.gravityScale = 0;
}
if (Input.GetKey (KeyCode.LeftShift)) {
move.y = 0;
rigidbody2D.velocity.Set(0, 0);
move.y += rigidbody2D.velocity.y * -1.0f;
}
if (Input.GetKeyUp (KeyCode.LeftShift))
rigidbody2D.gravityScale = 1.98f;

transform.position += (move + jumping) * Time.deltaTime;
//transform.position += Vector3.down* 9.8f * Time.deltaTime;
jumping.y *= .8f;
if (jumping.y < .2f)
jumping.y = 0;
}
}

2

May be rigidbody.velocity

3

Negative. I tried to set rigidBody. useGravity to false. Error Will not compile/run. There is only a rigidBody2D.

4

There seems to be an issue with

rigidbody2D.velocity.Set(0, 0);

If you change that to

rigidbody2D.velocity = new Vector2(0, 0);

it fixes the thrashing

Set should be setting it to x and y

I have not yet discovered why this happens though

edit: why do you have
rigidbody2D.velocity.y * -1.0f;
right after your .Set(0,0) ? what are hoping to multiply by 0 * -1 ?

5

I was trying to add its velocity, negated, thus making the mid air suspension.
The Vector2.zero worked. Thanks!