How to use Vector2.SmoothDamp?

I have 4 buttons in my scene and I am wanting each button to stretch completely across the panel they are in, gradually. So, I figured I would use Vector2.SmoothDamp since that allows me to gradually change the size. The only issue, there isn’t great examples on how to correctly use it, and the code I am using isn’t doing what I thought it would do. Here is my code:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class ExpanderTest : MonoBehaviour 
{
	public RectTransform rTrans;

	Vector2 panelMin, panelMax;
	Vector2 panelDefMin, panelDefMax;

	Vector2 refVelocity;

	void Start ()
	{
		panelMin = new Vector2 (0, 0);
		panelMax = new Vector2 (1, 1);

		panelDefMin = new Vector2 (0, 0.5f);
		panelDefMax = new Vector2 (0.5f, 1);
	}

	void FixedUpdate ()
	{
		if (Input.GetKeyDown(KeyCode.G))
		{
			rTrans.anchorMin = Vector2.SmoothDamp (panelDefMin, panelMin, ref refVelocity, 1, 5, Time.deltaTime);
			rTrans.anchorMax = Vector2.SmoothDamp (panelDefMax, panelMax, ref refVelocity, 1, 5, Time.deltaTime);
		}
	}
}

I’m not quite sure what I am doing wrong but instead of the button going from the top left half of the panel to the entire panel, it goes from the top left half to some random spot in the middle.

Edit: Had a wrong number in the panelDefMax part, but now that it’s fixed, it’s just being jittery and “shaking” around in it’s default position.

You are never reaching 1. PanelDefMin and PanelDefMax should be the current value. So, rTrans.anchorMin and eTrans.anchorMax.