Research On Decoupling And Singnal Compensation Of Multi-Dimensional Force/Tactile Sensor In Extreme Environment

Recently,research on intelligence robot technology has attracted wide attentions from the academic circles and the industrial circles.It has become one of major trends of robot development in future.As an important medium for intelligence robot to perceive external environment,sensor occupy the core position in intelligence robot system.Among them,the multi-dimensional force tactile sensor not only can realize the traditional rigid force/torque detection,but also can realize flexible tactile detection,which has very important research significance.Especially,in the extreme environment such as space,how to solve the problem of redundant operation of multidimensional force tactile sensor,precision operation under large temperature difference and flexible operation is one of the key issues in the research of robots in the extreme environment of aerospace.Research status on the multidimensional force tactile sensor was introduced in this paper.Multidimensional force tactile sensors can be divided into three-dimensional flexible tactile sensor and six-dimensional force/torque sensor(hereinafter referred as the six-dimensional force sensor)according flexibility and rigidity of the texture materials.At the same time,we also summarized the development status of intelligent algorithms in multi-dimensional force tactile sensors.This paper is to address a series of problems in application of multidimensional force tactile sensors,such as strong coupling among different dimensions of the sensor bridge circuit,poor flexibility of flexible sensor and poor robustness of rigid sensors.Therefore,structural design,stress analysis,decoupling,fault-tolerance processing and temperature compensation of sensors were explored by combining mechanics of materials,elastic mechanics,artificial intelligence and sensor technology.It lays a foundation for designing a multi-dimensional tactile sensor with soft stability and excellent fault tolerance.Main research contents are organized as follows.1.The fault-tolerance decoupling was performed by using coupling information among dimensions of the six-dimensional force sensor.The structure of six-dimensional force sensor with double E-membrane was introduced.The coupling relationship among bridge circuits in the six-dimensional force sensor was analyzed in detail.Coupling strengths among bridge circuits were expressed by slope quantification.The fault-tolerance decoupling by abandoning the fault bridge circuits was proposed based on the linear method.Besides,fault bridge circuit signals of the sensor were compensated and fault-tolerance decoupling was performed by using the nonlinear BP neural network algorithm.Experimental resultsdemonstrated that the coupling intensity can influence the fault-tolerance decoupling capability directly.2.Research on temperature compensation method for multi-dimensional force sensor under large temperature difference environmentThe influence of temperature variation on the measurement accuracy of six-dimensonal force sensor was analyzed based on the double E diaphragm type six dimensional force sensor strain gauge layout method.The adaptive fuzzy neural network is used to compensate the temperature of the sensor by constructing adaptive fuzzy neural network without changing the multidimensional force sensor of Wheatstone full bridge circuit and using the strain gauge self compensation method.The experimental results show that the stability of the sensor is obviously improved and the relative error of the maximum temperature drift of the sensor is not more than 0.1%.3.Decoupling study was based on N-type flexible sensorsThe force analysis of N-type microstructure sensitive unit prepared by conductive rubber is carried out.The calibration data based on this kind of microstructure sensor was obtained through finite element simulation experiments.A decoupling algorithm based on RBF neural network was proposed.The simulation results prove the effectiveness of the above work.4.Research on structure design and decoupling of multi-dimensional flexible tactile sensing unit with fault tolerance.For the flexibility,redundancy and temperature compensation of the sensor,a flexible piezoresistive film was used as a sensor sensor.A sensing element with a regular tetrahedral structure was designed to decompose three-dimensional forces to the corresponding sides of the structure.The force analysis of the sensor unit of the structure is carried out,the use of finite element analysis to verify the structure of the rationality and fault tolerance,through the design of experimental calibration data obtained by BP neural network nonlinear decoupling sensor,the experimental results show that The sensor realizes three-dimensional force measurement within the measuring range.The above research results have solved the problems such as the low measuring accuracy of multi-dimensional force tactile sensors,the inflexibility of flexible sensors,and the poor consistency of stability,which has improved the stability,sensitivity and reliability of multi-dimensional force tactile sensor systems.