Develop a computer program to control a Universal Robots UR5 robotic manipulator with a Robotiq 3-finger adaptive robot gripper, enabling it to perform object grasping operations by observing a human grasping an object and then attempting to replicate the action in the same manner. By observing the finger positions of the human hand during object grasping, the robot should decide which of the four available grasping modes of the gripper to apply for grasping the given object.