**1. Introduction**

For centuries, open surgery was the usual way of performing an operation on a patient. Usually large incisions were required, thus this technique was traumatic for the patient and resulted in large scars and long and expensive recovery time. One paradigmatic example is cardiac surgery, where for an open surgery procedure a sternotomy is required, where the surgeon has to open with a saw the patient's sternum to access the heart and create an adequate workspace. Minimally invasive surgery (MIS) has revolutionized the way surgeries are performed in the last few decades. Here endoscopes and specialized instruments that fit in natural openings in the body or through keyhole incisions (typically 5-12 mm in diameter) are used and meet the patients demand for smaller incisions and shorter recovery times.

MIS techniques have numerous benefits for patients over open techniques, but unfortunately there are several drawbacks: images are usually captured from a 2D endoscopic camera and displayed on a monitor, thus the surgeon has no stereoscopic view and looses depth perception in the operating field. Another drawback is that holding rigid and long shafted instruments and controlling them at a distance leads to higher fatigue and extremely limited tactile perception. Another severe disadvantage is that mirrored motions from that of the operating field are required, as instruments are pivoting about the incision point.
