Experimental results while the continuum laparoscope tracking the static instruments (Large Needle Driver and Grasping Retractor). Black points mean the initial position of tracking point in FOV. (a) Tracking the two surgical instruments respectively with different initial position. (b) Distances between the tracking point and the center of FOV while tracking the two surgical instruments respectively. (c) Tracking the two surgical instruments simultaneously. (d) Distances between the tracking point (center of the two instruments) and the center of FOV.