Hayashi T, Kurokawa M, Miyakawa M, Aizawa T, Kanaki A, Saitoh A, Ishioka K
Department of Information Engineering, Faculty of Engineering, Niigata University, Japan.
Front Med Biol Eng. 1994;6(3):171-86.
Photostereometry has widely been applied to the measurement of mandibular movements in 6 degrees of freedom. In order to improve the accuracy of this measurement, we developed a system utilizing small LEDs mounted on the jaws in redundant numbers and a 5000 pixel linear charge-coupled device (CCD) as a photo-sensor. A total of eight LEDs are mounted on the jaws, in two sets of four, by means of connecting facebows, each weighing approximately 55 g. The position of the LEDs are detected in three-dimensions by two sets of three CCD cameras, located bilaterally. The position and orientation of the mandible are estimated from the positions of all LEDs measured in the sense of least-squares, thereby effectively reducing the measurement errors. The static overall accuracy at all tooth and condylar points was considered to lie within 0.19 and 0.34 mm, respectively, from various accuracy verification tests.
摄影立体测量法已广泛应用于下颌运动六个自由度的测量。为了提高这种测量的准确性，我们开发了一种系统，该系统利用以冗余数量安装在颌骨上的小型发光二极管（LED）以及作为光传感器的5000像素线性电荷耦合器件（CCD）。通过连接面弓，总共八个LED以两组每组四个的方式安装在颌骨上，每个面弓重约55克。两组三个双边放置的CCD相机对LED的位置进行三维检测。根据所有LED的位置，采用最小二乘法估计下颌骨的位置和方向，从而有效减少测量误差。通过各种精度验证测试，所有牙点和髁突点的静态总体精度分别被认为在0.19毫米和0.34毫米以内。
