Force and tactile sensors are basic elements for robot perception and control, which call for large range and high-accuracy amplifier. In this paper, a novel conversion circuit for array tactile sensor is proposed by using nonlinear tent map phenomenon, which is characterized by sensitivity to small signal and nonlinear amplifying function. The tent map based conversion circuits can simultaneously realize amplifying and converting functions. The proposed circuit is not only simple but also easy to integrate and produce. It is very suited for multipath signal parallel sampling and converting of large array tactile sensor. 1. Introduction In recent decades, with the rapidly development of robot technology, robot sensors have received much attention as a sensing element for robot. Multiaxis force sensors and array tactile sensors, usually called haptic sensors, especially, have become the major research content in the robot sensor research areas [1, 2]. People hope that robot haptic sensor can be like human perception organs which have high measurement accuracy, with similar hand force and tactile organ of integration, miniaturization, and flexibility characteristics. For instance, Song developed a small four-degree-of-freedom wrist force sensor with high precision, which consists of small cross-elastic beam, compliant beams, and the base of the elastic body. It is a kind of self-decoupling force sensor in mechanical structure [3]. Beyeler et al. designed a six-axis MEMS force sensor with a movable body suspended by flexures which allow deflections and rotations along the -, -, and -axes. And the orientation of this movable body is sensed by seven capacitors based on transverse sensing, resulting in a high sensitivity [4]. Ma et al. proposed a novel nonlinear static decoupling algorithm based on the establishment of a coupling error model for 3-axis force sensor in order to avoid overfitting and minimize the negative effect of random noises in calibration data, which can obtain high precise measurement results of 3-axis force for robot force control [5]. Although robot array tactile sensor can be regarded as a multipoint integrated force sensor, due to flexible and miniaturization requirements of tactile sensor which are high, the measurement principle is more complex than the multiaxis force sensor [6, 7]. Song et al. proposed a novel design of a haptic texture sensor by using PVDF film to fabricate a high-accuracy, high-speed-response texture sensor [8]. Lee and Won developed a novel tactile imaging sensor by using a multilayer polydimethylsiloxane
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