Sun Qingyu, Okamoto Shogo, Wang Hongbo
IEEE Trans Haptics. 2024 Oct-Dec;17(4):992-997. doi: 10.1109/TOH.2024.3405728. Epub 2024 Dec 19.
The objective of this study was to investigate the influence of roughened surface features on the perceived hardness of various materials. Thirteen participants used a visual analog scale to evaluate the hardness of ten 3D-printed specimens by sliding a fingertip on them. The specimens had two types of surface features: flat and smooth, or with microscopic rectangular gratings. They were fabricated from two types of plastic with different Young's moduli-2.46 and 9.35 MPa. We found that both surface pattern and mechanical hardness significantly contributed to the perceived hardness of a material individually and without interaction. The roughened surfaces with rectangular gratings were judged to be harder than the flat and smooth surfaces of the same material. Among the parameters of the rectangular gratings, the groove width or periodic surface wavelength significantly contributed to the perceived hardness. Although the root cause of this phenomenon is unknown, friction caused by surface roughness is considered a potential mediator that influences the perceived hardness. The findings of this study can facilitate the manipulation of softness perception through surface design.
本研究的目的是调查粗糙表面特征对各种材料感知硬度的影响。13名参与者通过用指尖在10个3D打印样本上滑动，使用视觉模拟量表来评估它们的硬度。样本有两种表面特征：平坦光滑的，或带有微小矩形光栅的。它们由两种具有不同杨氏模量（2.46和9.35兆帕）的塑料制成。我们发现，表面图案和机械硬度均各自对材料的感知硬度有显著贡献，且不存在相互作用。带有矩形光栅的粗糙表面被判定比相同材料的平坦光滑表面更硬。在矩形光栅的参数中，凹槽宽度或周期性表面波长对感知硬度有显著贡献。尽管这种现象的根本原因尚不清楚，但表面粗糙度引起的摩擦被认为是影响感知硬度的潜在媒介。本研究的结果有助于通过表面设计来操控柔软度感知。
