Predicting 3D Motions from Single-Camera Optical Test Data

Journal Article · Fri Sep 18 00:00:00 EDT 2020 · Experimental Techniques

DOI:https://doi.org/10.1007/s40799-020-00391-8· OSTI ID:1667405

Rohe, D. P. ^[1]; Witt, B. L. ^[1]; Schoenherr, T. F. ^[1]

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1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

In a typical optical test, a stereo camera pair is required to measure the three-dimensional motion of a test article; one camera typically only measures motions in the image plane of the camera, and measurements in the out-of-plane direction are missing. Finite element expansion techniques provide a path to estimate responses from a test at unmeasured degrees of freedom. Treating the case of a single camera as a measurement with unmeasured degrees of freedom, a finite element model is used to expand to the missing third dimension of the image data, allowing a full-field, three-dimensional measurement to be obtained from a set of images from a single camera. The key to this technique relies on the mapping of finite element deformations to image deformations, creating a set of mode shape images that are used to filter the response in the image into modal responses. These modal responses are then applied to the finite element model to estimate physical responses at all finite element model degrees of freedom. The mapping from finite element model to image is achieved using synthetic images produced by a rendering software. Finally, the technique is applied first to a synthetic deformation image, and then is validated using an experimental set of images.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC04-94AL85000; NA0003525
• OSTI ID: 1667405
• Report Number(s): SAND--2020-8808J; 690141
• Journal Information: Experimental Techniques, Journal Name: Experimental Techniques Journal Issue: 3 Vol. 45; ISSN 0732-8818
• Publisher: Wiley
• Country of Publication: United States
• Language: English

Related Subjects

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finite element expansion
optical
structural dynamics
synthetic images