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Phase shifting profilometry can achieve high accuracy for the 3D shape measurement of static object. Errors will be introduced when the object is moved during the movement. The fundamental reason causing the above issue is: PSP requires multiple fringe patterns but the reconstruction model does not include the object movement information. This paper proposes a new method to automatically measure the 3D shape of the rigid object with arbitrary 2D movement. Firstly, the object movement is tracked by the SIFT algorithm and the rotation matrix and translation vector describing the movement are estimated. Then, with the reconstruction model including movement information, a least-square algorithm is applied to retrieve the correct phase value. The proposed method can significantly reduce the errors caused by the object movement. The whole reconstruction process does not need human intervention and the proposed method has high potential to be applied in industrial applications. Experiments are presented to verify the effectiveness.

When implementing the phase shifting profilometry to reconstruct an object, the object is always required to be kept stable as multiple fringe patterns are required. Movement during the measurement will cause failed reconstruction. This paper proposes a general model describing the fringe patterns with any three-dimensional movement based on phase shifting profilometry. The object movement is classified as five types and their characteristics are analyzed respectively. Then, by introducing a virtual plane, the influence on the phase value caused by different types of movement is described mathematically and a new model including movement information is proposed. At last, with the help of the movement tracking and least-square algorithm, the moving object is reconstructed with high accuracy. The proposed method can remove the reference plane during the reconstruction of the moving object, which extends the application range of the phase shifting profilometry. The effectiveness of the proposed model is verified by the experiments.