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Laparoscopic surgery is a minimally invasive surgical technique which is performed by using an endoscopic camera and long and slender instruments that are inserted through small incisions in the patient's abdominal wall. The indirect way of observing and manipulating complicates the surgeon's depth perception and disorders the surgeon's eye-hand coordination . This paper describes a concept of an endoscope positioning system that compensates misorientations between the surgeon's hand movements and the movements on the monitor by using a 90 ° endoscope. Movement parallax is realized by means of an endoscope positioning robot which is controlled by the surgeon's head movements.

A space manipulator is a lightweight robotic arm mounted on a space station or a spacecraft. If the manipulator is manually controlled from a remote site (teleoperation), the pictures from cameras in the neighbourhood of the manipulator are the only aids the human operator can use. Besides, manipulator dynamics and the possible presence of time delays in the control loop also complicate manual control. In space manipulator positioning tasks, the manipulator hand (the end-effector) has to be positioned accurately in front of a known (physical) target. This paper evaluates four control methods to position a space manipulator by hand with a force activated input device with six Degrees-of-freedom. With two of these methods, forward and downward end-effector control, the operator controls the movements of the end-effector (‘forward’ resp. ‘downward’ refer to the direction in which the input device must be pushed to let the end-effector move forward in the camera picture shown on the interface console in the remote control room). With the two other methods, the target is the controlled object. The results of man-machine experiments clarify that subjects by far prefer end-effector control above target control. Furthermore, subjects prefer controlling the end-effector in downward mode instead of in forward mode.

Currently, the space manipulator ERA (European Robot Arm) is being developed in Europe. It will be used on the international space station Alpha. When the ERA is controlled in manual control, its movements are monitored with camera’s, like the end-effector camera, which is used for positioning the ’hand’ of the manipulator. At the Delft University of Technology in the Netherlands, research is done on the development of a manmachine interface for the ERA. Herewith, the movements of the manipulator are animated on a graphical workstation. The input device is a 6 degrees of freedom Spaceball controller, which is used to control the velocity of the end-effector. In this paper, the development of a novel graphical display is discussed, that improves the spatial observability of the end-effector camera picture. In this display, the spatial information is presented by means of intersections between 3-dimensional graphical objects. Also, a control method is described, that transforms the movements of the Spaceball into movements in the end-effector camera picture. Finally, some results of man-machine experiments with the display and the control method are given.