电触觉是目前虚拟现实技术触觉实现方法的重要手段,然而由于缺乏触感量化和不同刺激模式下同种触感再现效果比较方法,一定程度上阻碍着电触觉应用的广泛开展。本文以经典电刺激模型为基础,研究了不同刺激模式下3种皮肤机械感受器(Meissner触觉小体,Merkel触盘和Pancinian环层小体)的刺激响应,分析了3种机械感受器最优刺激范式,以及电极间距、数量等参数对于不同感受器响应的影响。首次引入神经纤维电位传导模型、对电触觉触感强度分级实验的机理和影响因素进行了理论分析和仿真实验,并以此为基础设计了不同刺激模式的实现方式。最后通过指尖电触觉心理学分级实验评价了不同模式下感受器的刺激效果,得到了对于两种感受器(Meissner触觉小体,Merkel触盘)独立刺激的最优刺激范式,为进一步提高电刺激触觉再现效果提供了理论和实验支持。
Electrotactile stimulation is one of key techniques to display tactile feeling in virtual reality, which has been well studied for decade years. However, its wide applications are still hindered due to the lack of quantization metrics, or effective evaluating method of the tactile feeling display under different stimulating modes. Here, based on the classical McNEAL model of cutaneous nerve under electrical stimulation, the response of three mechanoreceptors (Meissner's corpuscle, Merkel's disc and Pancinian corpuscle ) is investigated with different electrical stimulation methods. TInfluence of electrode distance, electrode quantity, and the optimal stimula- ting method of different mechanoreceptors is analyzed in detail. Besides, to further explain the mechanism and the influence factor of the haptic experiment of tactile feeling recognition, theoretical analysis and simulation are carried out, and a new theory combined with action potential conducting model of nerve fiber is presetend. Different electrical stimulation modes are designed to test the efficiency and effectiveness of the proposed theory. The stimulating effects of different mechanoreceptors are evaluated through psychophysical experiments of tactile feeling recognition in a trial-and-error way. The optimized method of the two mechanoreceptors (Meissner's corpuscle, Merkel's disc) with independent stimulating is obtained, which in turn lays both the theoretical and experimental foundation for further improving the effectiveness of the tactile feeling display.