| 摘要 |
Systems, apparati and methods for mapping a virtual model of a real object, such as a body part, to the real object are presented. Such virtual model can be generated, for example, from an imaging scan of the object, for example, using MRI, CT, etc. A camera with a probe fixed thereto can be moved relative to the object until a video image of the object captured by the camera appears to coincide on a video screen with the virtual model which is shown fixed on that screen. The position of the camera in a real coordinate system can be sensed, and the position in a virtual coordinate system of the virtual model relative to a virtual camera, by which the view of the virtual model on the screen is notionally captured, can be predetermined and known. From this, the position of the virtual model relative to the object can be mapped and a transform generated to position the object in the virtual coordinate system to approximately coincide with the virtual model. After completion of such an initial registration process, a second, refined, registration process can be initiated. Such refined registration process can include acquiring a large number of real points on the surface of the object. Such points can, for example, then be processed using an iterative closest point measure to generate a second, more accurate transform between the object and its virtual model. Further, the refined registration processing can be iterated and more and more accurate transforms generated until a termination condition is met and a final transform generated. Using the final transform generated by this process the virtual model can be positioned in the real coordinate system to substantially exactly coincide with the object. |
