基于多层感知机的金属表面光度-结构光测量数据融合方法  

Multilayer Perceptron-Based Fusion Method for Metal Surface Measurement Data by Multi-Sensors Incorporating Photometric Stereo and Structured Light

作　　者：杨沅松 王晰 任明俊 Yang Yuansong;Wang Xi;Ren Mingjun(School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学机械与动力工程学院,上海200240

出　　处：《光学学报》2023年第19期192-203,共12页Acta Optica Sinica

基　　金：国家自然科学基金面上项目(52175477)。

摘　　要：提出一种基于多层感知机的金属表面光度-结构光测量数据融合算法。设计了融合面结构光与光度立体视觉两种测量原理的复合传感器,分别获得同一相机坐标系下的缺失点云及完整法向量多模态数据。为有效融合两种数据,设计了基于位置编码的多层感知机网络,以点云为形状约束,以法向量为纹理约束,实现金属表面完整的高精度三维重建。通过仿真和实验验证了所提方法的有效性。实验结果表明:该方法有效避免了法向量积分累计误差的问题,在获取完整点云的同时,测量精度相较于结构光测量系统提升了50.4%。Objective Accurate reconstruction of the workpiece surface is crucial to evaluate the machining process and control product quality.Non-contact three-dimensional(3D)reconstruction methods are widely employed due to their low cost,high measurement speed,and high measurement accuracy.Common non-contact reconstruction methods,such as structured light technology,photogrammetry,and laser scanning,generally assume a diffuse surface.However,the machined metal surfaces obviously deviate from this assumption and exhibit complicated high light reflectance,which incurs heavy high-frequency noises and numerous invalid measurement data.Although high dynamic structured light research works focus on this challenge,all these methods fail to break the assumption of diffuse surface,and thus the measurement efficiency is low,and the recovery of missing measurement data is limited.Compared with these methods,photometric stereo can estimate the complete surface normal of the metal surface and overcome the influence of non-diffuse reflectance by inversely modeling the reflectance.However,the error accumulation happens during the normal integration,resulting in distorted shapes.In order to solve these problems,a multilayer perceptron-based fusion method is proposed for metal surface measurement by multi-sensors incorporating photometric stereo and structured light.The point cloud by structured light offers the geometry constraint,and the surface normal by photometric stereo provides the texture constraint.As a result,the accurate 3D reconstruction of the metal surface is achieved by fusing the point cloud and the surface normal.Methods In this paper,one multi-sensor system including several light-emitting diodes(LEDs),one projector,and one camera is designed,and the structured light measurement is achieved by the projector and the camera.The photometric stereo system consists of the camera and the LEDs.These two measurement sensors share the same camera,and thus the error of coordinate system matching is avoided.The structured light gi

关 键 词：测量 结构光 光度立体视觉 视觉测量 复合传感器 多层感知机 

分 类 号：TP274[自动化与计算机技术—检测技术与自动化装置]