square with curves Motion

I have an object i want to move in a square motion, i also need the ability to have rounded corners.
I saw lots of guides on how to make circular motion like this one:

but none for what i'm looking for.

I would appreciate your help.

 

You could exponentiate your trig functions:

Code (CSharp):

1. public class Sphere : MonoBehaviour
2. {
3.     private float radius = 3f;
4.     private float exp = 0.5f;
5.     private float incr;
6.  
7.     void Update ()
8.     {
9.         incr += Time.deltaTime;
10.         float cos = Mathf.Cos(incr);
11.         float sin = Mathf.Sin(incr);
12.         transform.position = new Vector3
13.         (
14.             radius * Mathf.Pow(Mathf.Abs(cos), exp) * Mathf.Sign(cos),
15.             radius * Mathf.Pow(Mathf.Abs(sin), exp) * Mathf.Sign(sin),
16.             0f
17.         );
18.     }
19. }

The resulting movement is not even though.

 

Thanks !! You've been a great help.