An Intrinsically Embedded Flexible Pressure-temperature Dual-Mode Sensor Towards Soft Robotics

In recent years,soft robotics have attracted great attention due to their flexibility and versatility.Unlike their rigid counterparts,most soft robots can be adaptively deformed and actuated in various extreme environments.Soft robots require multiple perception capabilities that can opportunely perceive feedback on time,and to perform robot-environment interactions more safely and accurately is one of the current focuses of research in the field of soft robotics.Based on this,this paper proposes a new design of an intrinsically embedded flexible pressure-temperature dual-mode sensor towards soft robotics,which is capable of sensing pressure and temperature.The following is the research content of this paper:（1）Design and preparation of intrinsically embedded flexible pressure-temperature dual-mode sensor.To solve the problems of low integration and mismatch of modulus of sensors and soft robots,starting from the actual preparation process of soft robots,this article innovatively proposes that two grooves are formed on the bottom skin of the soft robot,and two grooves are filled with polydimethylsiloxane/carbon black（PDMS/CB）temperature-sensitive conductive composite material,the flexible pressure-temperature dual-mode sensor is intrinsically embedded in the soft robot.In addition,the preparation of sensors and soft robots uses silicone elastomer as the main material,which has the advantage of modulus matching.The sensor has a vertically stacked three-layer structure configuration,which is the PDMS/CB layer on the top and bottom layers,and the bottom skin of the soft robot in the middle layer.The overall structure is composed of a capacitive pressure sensor to sense pressure,and temperature is sensed through the resistance change of the temperature-sensitive conductive composite material on the top layer.There is no crosstalk between pressure and temperature sensing.（2）Performance test of the flexible pressure-temperature dual-mode sensor.This paper analyzes in detail the sensitivity(0.08 k Pa^-1in the ultra-low pressure range),repeatability,stability（>43000 times）,response time（100 ms）,and bending insensitivity characteristics of pressure sensing of the sensor.At the same time,the sensitivity(0.053℃^-1in the high temperature range),repeatability,stability（12 times）,response time（～5 s）and bending insensitivity characteristics of temperature sensing of the sensor are analyzed.The experimental verification was carried out to verify that there is no crosstalk between pressure sensing and temperature sensing of the sensor.（3）Application of the integration of flexible pressure-temperature dual-mode sensors and soft robots.The sensors are respectively integrated with the soft robotic gripper,the soft robotic hand and the crawling soft robot.The soft robots distinguish the size,weight,hardness,contact interface and temperature changes of the contacting object through pressure sening and temperature sensing.This intrinsically embedded method has broad application prospects for the integration of soft robots and flexible multi-modal sensors in the future.