Understanding electrotactile parametric properties is a crucial milestone in achieving intuitive haptics. Perceptual intensity is a primary property, but its exploration remains challenging due to subjectivity. To address this problem, this study conducted two experiments on fingertips and proposed two metrics based on significant findings. Experiment 1 found a significant linear relationship (R $^{2}$ = 0.981) between pulse amplitude (PA) and pulse width (PW) in the logarithmic plane, and proposed a metric of parameter intensity (PI) to estimate the intensity of parameters. In Experiment 2, subjective intensity (SI) was defined and measured using a scale of 0 to 10. A metric model of SI (SI model) was derived based on the linear relationship (R $^{2}>$ 0.78) between PI and measured SI. A calibration method was proposed and its prediction accuracy has been verified. An average RMSE of 11.2 $\%$ indicated an accuracy close to the subjective judgment error of 8.7 $\%$ . Results are consistent across subjects and four different electrode-skin conditions (ESC). The findings of this study provide theoretical support for SI prediction and regulation, which is significant for electrotactile feedback.

中文翻译：

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使用指尖电触觉刺激探索感知强度特性


了解电触觉参数属性是实现直观触觉的一个重要里程碑。感知强度是一个主要属性，但由于主观性，其探索仍然具有挑战性。为了解决这个问题，本研究在指尖上进行了两项实验，并根据重要发现提出了两个指标。实验1发现显着的线性关系（R $^{2}$ = 0.981）在对数平面上的脉冲幅度（PA）和脉冲宽度（PW）之间，并提出了参数强度（PI）的度量来估计参数的强度。在实验2中，使用0到10的尺度定义和测量主观强度（SI）。基于线性关系（R）推导出SI的度量模型（SI模型） $^{2}>$ 0.78) PI 和测量的 SI 之间。提出了一种标定方法并验证了其预测精度。平均 RMSE 为 11.2 $\%$表明准确度接近主观判断误差 8.7 $\%$ 。结果在受试者和四种不同的电极皮肤条件 (ESC) 中是一致的。本研究结果为SI预测和调控提供了理论支持，对于电触觉反馈具有重要意义。