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Accurate acquisition of the 3D facial data is very important for designing face prosthesis to restore the patients' appearance. In this paper, a 3D optical measurement system based on fringe projection is development for facial prosthesis. Compared with CT, MRI or laser scanning, this system is fast, safe and cost less. The developed system consist...
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... analysis. The two sensors have fixed relative position with the aid of a rod mounted on a 2D moving mechanism. The 2D moving mechanism can move the sensors to a suitable measurement position according to every individual patient by translating up and down to a proper height, and by translating back and forth to a proper measurement distance. Fig. 2 shows the detailed design of the slide projector. Compare with the commercial digital projector, the slide projector has the advantages of continuous intensity, high contrast, high radiant flux, which is suitable to measure the dark face defective regions [8]. The slide projector utilizes a physical grating with desired gray code and ...
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Citations
... As a non-contact and precise measurement method, optical 3D measurement has been an important auxiliary method for modern medical diagnosis and rehabilitation. The acquisition of 3D shapes for specific body parts is essential in processes such as body shape measurement and analysis [1][2][3][4], augmentation mammoplasty [5], prosthesis design [6,7], fracture immobilization object design [8,9], etc. As the CAD model is created via optical 3D measurement, 3D printing technology can be directly used to fabricate orthoses or prosthetics. ...
Human body measurement is essential in modern rehabilitation medicine, which can be effectively combined with the technology of additive manufacturing. Digital image correlation based on laser speckle projection is a single-shot, accurate, and robust technique for human body measurement. In this paper, we present a handheld anthropometric measurement system based on laser speckle projection. A flexible retroreflective marker target is designed for multi-view data registration. Meanwhile, a synchronous redundancy-reduction algorithm based on a re-projected global disparity map is proposed. Experiment results validate that the proposed system is effective and accurate for different human body part measurements. Comparative experiments show that the proposed redundancy-reduction algorithm has high efficiency and can effectively preserve the features of complex shapes. The comprehensive performance of the algorithm is better than the other two tested methods.
... Fringe projection is a crucial kind of optical three-dimensional (3D) measurement technology [1] that is becoming increasingly used in various fields [2][3][4][5][6] such as industrial quality control, rapid prototyping, cultural heritage preservation, and human body 3D measurement. Unfortunately, sinusoidal fringe projection has some inevitable issues when performing such tasks relying on digital projectors, in that the measurement speed is limited by the maximum image switching rate of the projector. ...
Balancing the accuracy and speed of three-dimensional (3D) surface measurement of objects is crucial in many important applications. In this paper, we present a wrapped phase and pseudorandom image method and develop an experimental system aiming to avoid the process of phase unwrapping. Our approach can reduce the length of image sequences and improve the speed of pattern projection and image acquisition and can be used as a good candidate for high-speed 3D measurement. The most critical step in our new methodology is using the wrapped phase and the epipolar constraint between one camera and a projector, which can obtain several candidate 3D points within the measurement volume (MV). The false points from the obtained candidate 3D points can be eliminated by the pseudorandom images. A systematic accuracy with MV better than 0.01 mm is achievable. 3D human body measurement results are given to confirm the fast speed of image acquisition capability.
... Chen et al. in [21] propose a 3D optical measurement system based on fringe projection to be applied for facial prosthesis fabrication. The instrument is cost-effective and consists of two measurement sensors, which can scan and register both sides of the patients' face. ...
3D vision systems are more and more required in a large variety of applications and mostly for mechanical and medical purposes. This paper presents the study and realization of a prototype of a structured light automated tilt-rotational 3D vision system for high-quality reconstructions of components of various sizes and in cases of freeform and complex surfaces. The main goal of this research work was to develop an instrument with the following main novelties: configurability for different object sizes, high precision and resolution levels and ability to automatically generate the mesh representing the full scanned objects without any intervention of the operator by means of a 2 degrees of freedom automated tilt-rotational mechanical positioning system. A detailed analysis of the instrument and the procedures and results of the performance tests are presented, together with the examination of possible strategies to obtain a better performance, especially by the calibration and the synchronization between the optical and the mechanical systems. As a result, the prototype and the performance parameters resulting from the experimental campaigns, are reported.
... The outcome of this is the high-resolution and accurate 3D reconstruction. These attributes make them highly preferred in clinical environments [14][15][16][17][18][19] . The recent evolution in hardware resources and new acquisition techniques capacitates the 3D measurements of moving objects even if the series of patterns must be realized [20] . ...
Abstract The state of the art techniques used by medical practitioners to extract the three-dimensional (3D) geometry of different body parts requires a series of images/frames such as laser line profiling or structured light scanning. Movement of the patients during scanning process often leads to inaccurate measurements due to sequential image acquisition. Single shot structured techniques are robust to motion but the prevalent challenges in single shot structured light methods are the low density and algorithm complexity. In this research, a single shot 3D measurement system is presented that extracts the 3D point cloud of human skin by projecting a laser speckle pattern using a single pair of images captured by two synchronized cameras. In contrast to conventional laser speckle 3D measurement systems that realize stereo correspondence by digital correlation of projected speckle patterns, the proposed system employs KLT tracking method to locate the corresponding points. The 3D point cloud contains no outliers and sufficient quality of 3D reconstruction is achieved. The 3D shape acquisition of human body parts validates the potential application of the proposed system in the medical industry.
... The outcome of this is the high-resolution and accurate 3D reconstruction. These attributes make them highly preferred in clinical environments [14][15][16][17][18][19] . The recent evolution in hardware resources and new acquisition techniques capacitates the 3D measurements of moving objects even if the series of patterns must be realized [20] . ...
The state of the art techniques used by medical practitioners to extract the three-dimensional (3D) geometry of different body parts requires a series of images/frames such as laser line profiling or structured light scanning. Movement of the patients during scanning process often leads to inaccurate measurements due to sequential image acquisition. Single shot structured techniques are robust to motion but the prevalent challenges in single shot structured light methods are the low density and algorithm complexity. In this research, a single shot 3D measurement system is presented that extracts the 3D point cloud of human skin by projecting a laser speckle pattern using a single pair of images captured by two synchronized cameras. In contrast to conventional laser speckle 3D measurement systems that realize stereo correspondence by digital correlation of projected speckle patterns, the proposed system employs KLT tracking method to locate the corresponding points. The 3D point cloud contains no outliers and sufficient quality of 3D reconstruction is achieved. The 3D shape acquisition of human body parts validates the potential application of the proposed system in the medical industry.
... During the last decades, the use of fringe projection techniques for recovering three-dimensional surface data has become an active research area in optical metrology. Recent major impact applications of this technique are related to biometrics1234, commonly used for measurements on the human body. In profilometry, fringe analysis is a key task which significantly influences the overall performance of the whole system in terms of number of images required, resolution and accuracy of measurement and computational requirements [5]. ...
We present preliminary results of a swordfish bone measurements using the fringe projection technique. A phase correlation algorithm for phase shifting profilometry is compared in performance with the classic Fourier transform approach for phase extraction.
The use of machining systems by Computer Numerical Control (CNC) has notable advantages in the area of industrial production compared with traditional techniques. This facilitates a significant decrease of time, higher precision and optimization of operation parameters. The control of sequences in these systems is based on codes that define the parameters to produce the machining of a determined piece. However, the generation of these codes presents two major challenges, first, know the tridimensional information of the piece to produce, and second, define the sequence by CNC machining. In this work, the fringe projection technique is used to obtain three-dimensional information from an object and based on this information, automatically generate programming codes for the machining routine of a three-axial CNC milling machine. The results are compared to apply the fringe projection technic to recover three-dimensional shape of an object based on Least Squares Algorithm, using information from three to eight images.
