To increase diversity and realism, surface bidirectional scattering distribution functions (BSDFs) are often modelled as consisting of multiple layers, but accurately evaluating layered BSDFs while accounting for all light transport paths is a challenging problem. Recently, Guo
Characterizing the Effects of Haptic Rendering Parameter Variations on Perceived Kinesthetic Rendering Accuracy
To understand how the realism of a kinesthetic haptic rendering is affected by the accurate selection of the rendering model parameters, we conducted a preliminary user study where subjects compared three real-world objects to their equivalent haptic rendering. The subjects rated the rendering realism as the model parameters were varied about their nominal values. The results suggest that the required accuracy of various haptic rendering parameters is not equally important when considering the perceived realism.
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- Award ID(s):
- 1830242
- NSF-PAR ID:
- 10284613
- Publisher / Repository:
- IEEE
- Date Published:
- Format(s):
- Medium: X
- Location:
- Montreal, QC, Canada
- Sponsoring Org:
- National Science Foundation
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Abstract et al . [GHZ18] proposed an accurate and general position‐free Monte Carlo method, but this method introduces variance that leads to longer render time compared to non‐stochastic layered models. We improve the previous work by presenting two new sampling strategies,pair‐product sampling andmultiple‐product sampling . Our new methods better take advantage of the layered structure and reduce variance compared to the conventional approach of sequentially sampling one BSDF at a time. Ourpair‐product sampling strategy importance samples the product of two BSDFs from a pair of adjacent layers. We further generalize this tomultiple‐product sampling , which importance samples the product of a chain of three or more BSDFs. In order to compute these products, we developed a new approximate Gaussian representation of individual layer BSDFs. This representation incorporates spatially varying material properties as parameters so that our techniques can support an arbitrary number of textured layers. Compared to previous Monte Carlo layering approaches, our results demonstrate substantial variance reduction in rendering isotropic layered surfaces. -
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Despite the large amount of research on kinesthetic haptic devices and haptic effect modeling, there is limited work assessing the perceived realism of kinesthetic model renderings. Identifying the impact of haptic effect parameters in perceived realism can help to inform the required accuracy of kinesthetic renderings. In this work, we model common kinesthetic haptic effects and evaluate the perceived realism of varying model parameters via a user study. Our results suggest that parameter accuracy requirements to achieve realistic ratings vary depending on the specific haptic parameter.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/WHC49131.2021.9517158
