Characterization and Psychophysical Studies of an Air-Jet Lump Display
Characterization and Psychophysical Studies of an Air-Jet Lump Display
复制标题
DOI：
10.1109/toh.2012.71
复制
发表时间：
2013-04-01
影响因子：
2.9
通讯作者：
Okamura, Allison M.
中科院分区：
文献类型：
--
作者：
Gwilliam, James C.;Bianchi, Matteo;Okamura, Allison M.
在机器人辅助微创手术期间，由于尺寸和重量的限制，开发用于增强肿块触诊的触觉显示器具有挑战性，这促使了一种气动驱动策略的产生。这项工作描述了一种喷气式触觉显示器的定量和心理物理学评估，该显示器通过将加压空气经一个小孔导向手指来产生肿块感知。气压和孔径大小分别旨在控制感知到的肿块的硬度和大小。在不同的孔径大小和压力下，通过电容式触觉传感器和质量流量计测量了射流冲击压力和流速。喷气压力分布宽度正如射流理论所预测的那样变化，并且在很大程度上与供给压力（以及因此的射流出口速度）无关。采用恒定刺激法来确定气压和孔径大小的恰可察觉差异（JND）。定性结果表明，受试者将刺激感知为“肿块样”形状。压力的恰可察觉差异范围为19.6 - 24.4千帕（表压），孔径大小的恰可察觉差异范围为0.50 - 0.66毫米。供给压力与感知到的肿块大小变化之间不存在显著相关性。然而，压力的恰可察觉差异与孔径大小呈显著（p < 0.001）负相关，在较大孔径处辨别能力提高，因为此时更大的指垫区域受到刺激。
Development of tactile displays to enhance palpation of lumps during robot-assisted minimally invasive surgery is challenging due to size and weight constraints, motivating a pneumatic actuation strategy. This work describes the quantitative and psychophysical assessment of an air-jet tactile display that creates a lump percept by directing pressurized air through an aperture onto the finger. The air pressure and aperture size are meant to control the hardness and size, respectively, of the perceived lump. Jet impingement pressure and flow rate were measured by capacitive tactile sensors and mass flow meters at varying aperture sizes and pressures. The air-jet pressure profile width evolves as jet theory predicts and is largely independent of supply pressure (and therefore jet exit velocity). The method of constant stimuli was used to determine the just noticeable differences (JNDs) for the air pressure and aperture size. Qualitative results indicate that subjects perceive the stimulus as a "lump-like" shape. Pressure JNDs ranged from 19.6-24.4 kPag and aperture size JNDs ranged from 0.50-0.66 mm. No significant correlation exists between the supply pressure and changes in perceived lump size. However, pressure JNDs show significant (p < 0: 001) inverse correlation with aperture size, with improved discrimination at larger apertures, where a greater finger pad area is stimulated.