Electronic skin for robotic tactile sensing has been studied extensively over the past years, yet practical applications of electronic skin for the grasping state monitoring during robotic manipulation are still limited. In this study, we present the fabrication and implementation of electronic skin sensor arrays for the detection of unstable grasping. The piezoresistive sensor arrays have the advantages of facile fabrication, fast response, and high reliability. With the tactile data from the sensor array, we propose two quantitative indicators, correlation coefficient and wavelet coefficient, to identify grasping with variable forces and slippage. Those two indicators reflect both time and frequency domain characteristics in the contact forces from the sensor array and can be obtained without large amount of calculation. We demonstrate the utility of this method under various conditions, the results indicate grasping with variable forces, and slippage can be distinguished by this method. The flexible sensor arrays are adopted for tactile sensing on a bionic hand, and the effectiveness of this method in detecting various grasping states has been verified. The electronic skin sensor array and the grasping state monitoring method are promising for applications in robotic dexterous manipulation.

中文翻译：

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用于监测机器人操纵过程中抓取状态的柔性电子皮肤

用于机器人触觉传感的电子皮肤在过去几年中得到了广泛研究，但电子皮肤在机器人操作过程中用于抓取状态监测的实际应用仍然有限。在这项研究中，我们介绍了用于检测不稳定抓握的电子皮肤传感器阵列的制造和实施。压阻式传感器阵列具有制作容易、响应速度快、可靠性高等优点。利用来自传感器阵列的触觉数据，我们提出了两个定量指标，即相关系数和小波系数，以识别变力和滑动的抓取。这两个指标反映了传感器阵列接触力的时域和频域特性，无需大量计算即可获得。我们展示了这种方法在各种条件下的实用性，结果表明可以用变力抓取，并且可以通过这种方法区分滑动。采用柔性传感器阵列对仿生手进行触觉感知，验证了该方法在检测各种抓握状态方面的有效性。电子皮肤传感器阵列和抓取状态监测方法有望在机器人灵巧操作中得到应用。