Research On Strain-based Monolithically Integrated Multimode Sensing For Compact Design Of Compliant Actuator

This paper presents a compact strain-based multimode sensor which is monolithically integrated in a compound bridge-type compliant mechanism.High-level integration and multimode sensing are the characteristics of the sensor.The sensor is integrated into a bridge-type compliant mechanism,and can be applied in a variety of occasions in which permitted occupied space is limited.The sensor uses the strain gauges integrated into the composite bridge-type compliant actuator as a sensing unit,and is easily switched to a different sensing modes,including the output displacement,input displacement,and input force sensing modes in the same strain gauges configuration.The finished works can be categorized into the following aspects:1)Structure design of strain-based multimode sensor,sensing model and analysisThe bridge amplification mechanism based on amplification coefficient in meeting its requirements,considering the installation position and the strain bridge strain gauge selection,the original bridge amplifier is improved and designed multi modal sensors a high inherent frequency and amplification of leaf type double flexible hinge coefficient,large lateral stiffness of the.The best bonding position of the strain gauge is determined by the finite element analysis.2)The establishment of the sensor model and the finite element analysis of the staticcharacteristics of the sensorAccording to the geometric theory of elastic beam and the improved analysis method,derived mathematical model,input force sensor output / input displacement sensor mathematical model,and then,through the finite element simulation analysis method,analysis of all the sensing model in with / without sensing output characteristics under load,verify the sensor under no load or load is relatively small under the condition of having good linear sensing properties.3)Dynamic characteristics and finite element analysis of sensorsThrough the analysis of the factors influencing the dynamic characteristics of the sensor,the strain gauge and the bridge amplification mechanism allows the highest frequency,and the effect of load coupling effect,followed by the use of Carle second theorem theory,and then do the simulation analysis of the sensor load and different input force under different conditions in finite element.The results show that the sensitivity coefficient of the sensor is closely related to the output load.4)Experimental research on the static,dynamic sensing characteristic and the load coupling effect of the sensorIn order to evaluate the presented sensor,a lot of experiments are implemented considering the different sensing characteristics in different conditions,such as the static sensing performance of linearity,accuracy,sensitivity etc.,and dynamic sensing performance of output load effect,bandwidth etc..Besides,the derived sensing models are verified by the experiments.The experiments indicates the accuracies of the presented multimode sensors can reach nanometric accuracy for the displacement sensing mode and the sub-Newton-level for the force sensing mode,and that can fulfill the requirements of the nano-positioning stages...