Abstract: A folding optical path transfer videometrics method for measuring the three-dimensional position and attitude of non-intervisible objects is disclosed. In one aspect, the method includes the following: constructing a folding optic path between an invisible target and a reference, disposing transfer station comprising a camera, a cooperating mark and a laser range finder on each break point in the folding optic path. The method may further include processing an image shot by each camera, accounting for the distance measured by the laser range finder, obtaining a position and posture information corresponding to each adjacent transfer station, summing the values from the reference to the invisible target, and achieving three-dimensional position and posture of the invisible target relating to the reference.

Abstract: An invasive cardiac valve comprises a tubular stent (1) and a valve (2). One end of the tubular stent (1) is of a frusto-conical structure, the other end is wide open, and the diameter of the open end is greater than the diameter of the frusto-conical end. The valve (2) is attached to the frusto-conical end of the tubular stent (1); and a delivery and retrieval hole (4) of the cardiac valve is provided at the top of the open end of the tubular stent (1). Because the diameter of the open end is greater than the diameter of the frusto-conical end, the cardiac valve can be effectively fixed in a position of aortic annulus to prevent the cardiac valve displacement caused by the impact of the blood flow. Because the valve (2) is attached to the frusto-conical end of the tubular stent (1), the valve (2) can totally avoid the left and right coronary ostia and does not affect the haemodynamics of the coronary artery.

Abstract: The present invention provides a ground-based camera surveying and guiding method for aircraft landing and unmanned aerial vechicle recovery based on the camera surveying technology, which is a ground-based camera surveying and guiding system mainly including several video cameras arranged near the landing areas of an aircraft or an unmanned aerial vechicle. During the approaching process of the aircraft or the unmanned aerial vechicle, the system performs imaging of the aircraft in real time and detects movement parameters such as the track, velocity, acceleration, attitude and the offset relative to the glide slope of the aircraft or the unmanned aerial vechicle in real time by analyzing images and applying camera surveying method and technology, so as to provide guidance for aircraft landing or unmanned aerial vechicle recovery. The method is an autonomic guiding survey without interferences from others, which has high accuracy and reliability. The hardware devices are mature, simple and have low cost.

Abstract: A folding optical path transfer videometrics method for measuring the three-dimensional position and attitude of non-intervisible objects is disclosed. In one aspect, the method includes the following: constructing a folding optic path between an invisible target and a reference, disposing transfer station comprising a camera, a cooperating mark and a laser range finder on each break point in the folding optic path. The method may further include processing an image shot by each camera, accounting for the distance measured by the laser range finder, obtaining a position and posture information corresponding to each adjacent transfer station, summing the values from the reference to the invisible target, and achieving three-dimensional position and posture of the invisible target relating to the reference.