You are given a 2D environment with two circular obstacles of radius 1. One obstacle is located at (x0, y0) and the other at (x1, y1). You are also given a destination (xd,yd). Write a potential function, consisting of an attractive term and two repulsive terms, and the associated force that makes a point, omnidirectional robot reach the destination from any point in the 2D environment. Do not forget to normalize your force vector.