Visual field examination results using virtual reality glasses have a high correlation with the Humphrey perimeter allowing the method to be suitable for probable clinical use. High correlation coefficient ( r =0.808, P <0.0001) was found between the virtual reality visual field test and the Humphrey perimeter visual field. The results were compared with those obtained from the same patients using the Humphrey perimeter.
#Antwain walker cybertown software#
Virtual reality glasses, a smartphone with a 6 inch display, and software that implements a fast-threshold 3 dB step staircase algorithm for the central 24° of visual field (52 points) were used to test 20 eyes of 10 patients, who were tested in a random and consecutive order as they appeared in our glaucoma department. To present a visual field examination method using virtual reality glasses and evaluate the reliability of the method by comparing the results with those of the Humphrey perimeter. Tsapakis, Stylianos Papaconstantinou, Dimitrios Diagourtas, Andreas Droutsas, Konstantinos Andreanos, Konstantinos Moschos, Marilita M Brouzas, Dimitrios Visual field examination method using virtual reality glasses compared with the Humphrey perimeter. The paper presents the methodology and some numerical validation. It is shown that a single test performed at 45° to the rolling direction is sufficient to obtain all anisotropic plastic parameters, thus reducing experimental effort involved in characterisation.
The method combined with recently developed sensitivity-based virtual fields allows to optimally locate areas in the test where information about each material parameter is encoded, improving accuracy of the identification over the traditional user-defined virtual fields. In order to identify material parameters from the DIC data, an inverse method called the Virtual Fields Method is employed. This heterogeneity enables the identification of multiple material parameters in a single test. This specimen leads to heterogeneous states of stress and strain, the latter being measured using a stereo DIC system (MatchID). In this work, a characterisation method involving a deep-notched specimen subjected to a tensile loading is introduced. Sheet metals characterization using the virtual fields method The proposed sensitivity-based virtual fields were consistently able to identify plastic model parameters and outperform the stiffness-based and manually defined virtual fields when the data was corrupted by noise. To quantify the improvement offered by these new virtual fields, they were compared with stiffness-based and manually defined virtual fields. The sensitivity-based virtual fields were applied to a numerical example involving small strain plasticity however, the general formulation derived for these virtual fields is applicable to any non-linear constitutive model. These new sensitivity-based virtual fields reduce the influence of noise on the parameter identification.
In this manuscript, a new set of automatically-defined virtual fields for non-linear constitutive models has been proposed. The virtual fields method is an approach to inversely identify material parameters using full- field deformation data. Sensitivity-based virtual fields for the non-linear virtual fields method
0 kommentar(er)
