Abstract:
A method for automatically determining the 3D position and orientation of a radio-opaque medical object in a living body using single-plane fluoroscopy comprising capturing a stream of digitized 2D images from a single-plane fluoroscope (10), detecting the image of the medical object in a subset of the digital 2D images, applying pixel-level geometric calculations to measure the medical-object image, applying conical projection and radial elongation corrections (31) to the image measurements, and calculating the 3D position and orientation of the medical object from the corrected 2D image measurements.
Abstract:
A method for automatically determining the 3D position and orientation of a radio-opaque medical object in a living body using single-plane fluoroscopy comprising capturing a stream of digitized 2D images from a single-plane fluoroscope (10), detecting the image of the medical object in a subset of the digital 2D images, applying pixel-level geometric calculations to measure the medical-object image, applying conical projection and radial elongation corrections (31) to the image measurements, and calculating the 3D position and orientation of the medical object from the corrected 2D image measurements.
Abstract:
A method for detecting an R-wave from an ECG signal (x(t)) derived from a living body, the method comprising the steps of (a) acquiring the ECG signal from the living body, (b) digitizing the ECG signal into a digital ECG signal (x(ti)), (c) filtering the digital ECG signal with a bandpass filter (53) and applying an absolute value filter (55) thereto to create a filtered ECG signal (g(ti)), (d) for each sequential value of the filtered ECG signal, comparing (57) the filtered ECG signal to an ECG tracking threshold (TT), (e) if the filtered ECG signal is no greater than TT, incrementing a counter (59), but if greater than TT, setting the counter to zero; and (f) comparing (63) the counter to a predetermined refractory count RC and, if the count is equal to RC, outputting an R-wave trigger indicating that an R-wave has been detected.
Abstract:
A method and apparatus (10) for cutting a graphics area (42a) from a sheet (40) of material which also includes a plurality of registration marks (44) at and about the graphics area in predetermined positions. The method involves steps to ascertain the position and orientation of the sheet as placed on the apparatus, sensing the locations of the marks at the time of cutting, and cutting the graphics area from the sheet along a path determined in response to the sensed positions of the marks with respect to graphics area at that time. Certain embodiments use either (a) a subset (46) of marks which is applied on one side of graphics area or (b)certain reference features (49), such as edges and corners of the sheet and elements of the graphics area, to ascertain the position and orientation of the sheet on the apparatus. The invention provides rapid, automated, and precise cutting despite two-dimensional distortion of the sheet.
Abstract:
A method for preparing a graphic on a sheet (40) of material which also includes at least one registration mark (44) at and about the graphic in predetermined positions. The method involves the steps of applying the graphic (42a, 42b) and at least one registration mark on a sheet of material in positions according to layout data, transferring the layout data to a processing controller, placing the sheet of material on a sheet-receiving surface (16), sensing the position of the registration mark on the sheet of material, and utilizing the layout data and the position of the registration mark to precisely narrow-path-process around the graphic on the sheet of material. Certain embodiments use either (a) a subset (46) of marks which is applied on one side of graphic or certain reference features, such as edges and corners of the sheet and elements of the graphic, to ascertain the position and orientation of the sheet on the apparatus. The invention provides efficient, rapid, automated, and precise processing around the graphic.
Abstract:
A method for preparing a graphic on a sheet (40) of material which also includes at least one registration mark (44) at and about the graphic in predetermined positions. The method involves the steps of applying the graphic (42a, 42b) and at least one registration mark on a sheet of material in positions according to layout data, transferring the layout data to a processing controller, placing the sheet of material on a sheet-receiving surface (16), sensing the position of the registration mark on the sheet of material, and utilizing the layout data and the position of the registration mark to precisely narrow-path-process around the graphic on the sheet of material. Certain embodiments use either (a) a subset (46) of marks which is applied on one side of graphic or certain reference features, such as edges and corners of the sheet and elements of the graphic, to ascertain the position and orientation of the sheet on the apparatus. The invention provides efficient, rapid, automated, and precise processing around the graphic.