A hybrid compensation scheme for piezoelectric ceramic actuators(PEAs)is proposed.In the hybrid compensation scheme,the input rate-dependent hysteresis characteristics of the PEAs are compensated.The feedforward contr...A hybrid compensation scheme for piezoelectric ceramic actuators(PEAs)is proposed.In the hybrid compensation scheme,the input rate-dependent hysteresis characteristics of the PEAs are compensated.The feedforward controller is a novel input rate-dependent neural network hysteresis inverse model,while the feedback controller is a proportion integration differentiation(PID)controller.In the proposed inverse model,an input ratedependent auxiliary inverse operator(RAIO)and output of the hysteresis construct the expanded input space(EIS)of the inverse model which transforms the hysteresis inverse with multi-valued mapping into single-valued mapping,and the wiping-out,rate-dependent and continuous properties of the RAIO are analyzed in theories.Based on the EIS method,a hysteresis neural network inverse model,namely the dynamic back propagation neural network(DBPNN)model,is established.Moreover,a hybrid compensation scheme for the PEAs is designed to compensate for the hysteresis.Finally,the proposed method,the conventional PID controller and the hybrid controller with the modified input rate-dependent Prandtl-Ishlinskii(MRPI)model are all applied in the experimental platform.Experimental results show that the proposed method has obvious superiorities in the performance of the system.展开更多
CuO added Pb0.92Sr0.06Ba0.02（Mg1/3Nb2/3）0.25（Ti0.53Zr0.47）0.75O3 ceramics were studied to prepare high-quality multilayer piezoelectric actuators with pure Ag electrodes at 900 ℃. CuO addition not only reduced th...CuO added Pb0.92Sr0.06Ba0.02（Mg1/3Nb2/3）0.25（Ti0.53Zr0.47）0.75O3 ceramics were studied to prepare high-quality multilayer piezoelectric actuators with pure Ag electrodes at 900 ℃. CuO addition not only reduced the sintering temperature significantly from 1260 ℃ to 900 ℃ but also improved the ceramic density to 7.742 g/cm3. The 0.7 wt.% CuO added ceramic sintered at 900 ℃ shows the remnant polarization （Pr） of 40 μC/cm2, 0.28% strain at 40 kV/cm, and the piezoelectric coefficient （d33） of 630 pC/N. This ceramic shows a strong relaxor characteristic with a Curie temperature of 200 ℃. Furthermore, the 0.7 wt.% CuO added ceramic and pure Ag electrodes were co-fired at 900 ℃ to prepare a high-quality multilayer piezoelectric actuator with a d33 of over 450 pC/N per ceramic layer.展开更多
Rainbow piezoelectric ceramics are a new type of stress-biased,oxide-reduced composite ferroelectric ceramics,which have a special dome structure.The have shown excellent properties such as ultra-high displacement und...Rainbow piezoelectric ceramics are a new type of stress-biased,oxide-reduced composite ferroelectric ceramics,which have a special dome structure.The have shown excellent properties such as ultra-high displacement under an applied electric field and enhanced load-bearing capability.In this article,their manufacture,structures and properties were discussed in detail by combining experiments and theory analysis.The resuts show that the optimal conditions for producing Rainbow samples from PLZT ceramics were determined to be 900℃ for 1 to 1.5 hours.A number of different phases have been found in the reduced layer of Rainbow ceramics by XRD analyses.The phases found include metallic lead and other oxide phases,such as PbO,ZrO 2 and TiO 2.The original PLZT phase was not observed.The reduced layer was transgranularly fractured while the unreduced ceramic was intergranularly fractured.Two kinds of fracture types can be seen at the interface,which denotes the different degrees of reduction.It is shown that the Pb grains (about 0.2μm) constitute a continuous phase in the reduced layer,which accounts for the good electrical conductivity.展开更多
Multilayer ceramic actuator(MLCA)has been widely employed in actuators due to the large cumulative displacement under the low driving voltage.In this work,the MLCA devices consisting of a lead-free MnCO_(3-)and CuO-do...Multilayer ceramic actuator(MLCA)has been widely employed in actuators due to the large cumulative displacement under the low driving voltage.In this work,the MLCA devices consisting of a lead-free MnCO_(3-)and CuO-doped 0.96(K_(0.48)Na_(0.52))(Nb_(0.96)Ta_(0.04))O_(3)-0.04CaZrO_(3) piezoelectric ceramics and a base nickel(Ni)metal inner electrode were well co-fired by the two-step sintering process in a reducing atmosphere.The ceramic layer/electrode interface is well-integrated and clearly continuous without distinct interdiffusion and chemical reaction,which is beneficial to the electrical reliability of the MLCA.As a result,the MLCA laminated with nine active ceramic layers obtains an ultrahigh piezoelectric coefficient d_(33) of 3157 pC/N,about 9 times than bulk ceramics.The 0.5 mm-thick MLCA composed of a series of~50μm-thick ceramic layers and~3μm-thick Ni electrodes reaches a high 1.8μm displacement under the low applied voltage of 200 V(the same displacement requires a voltage as high as 3700 V for~1 mm-thick bulk ceramics).The excellent electrical performance and low-cost base electrode reveal that the(K,Na)NbO_(3)(KNN)-based MLCAs are promising lead-free candidate for actuator application.展开更多
Piezoelectric ceramic element (PCE) is a kind of actuator applied widely on the intelligent material & structure. Establishing the relationship between the transferring stress and the controlling signal, namely t...Piezoelectric ceramic element (PCE) is a kind of actuator applied widely on the intelligent material & structure. Establishing the relationship between the transferring stress and the controlling signal, namely the transferring and actuating equation, is a key step to analyze the actuating performance of the PCE. Based on the method of the shear lag theory, the procedure of the stress transferring is analyzed and the transferring and actuating model is established in this paper. Some measurements for PCE(PZT5) actuating the Glass Fiber/Epoxy laminate have been done to verify the model established. The experimental results show that the theoretical model agrees well with the practice. Finally, the effect of the main factors on PCE actuating the laminate is studied by using the experimental and theoretical results.展开更多
A new type of large-displacement actuating materials called RAINBOW (Reduced and Internally Biased Oxide Wafer) ceramics is fabricated by a chemical reduction of PLZT piezoelectric ceramics. It is found that PLZT is e...A new type of large-displacement actuating materials called RAINBOW (Reduced and Internally Biased Oxide Wafer) ceramics is fabricated by a chemical reduction of PLZT piezoelectric ceramics. It is found that PLZT is easily reduced and the thickness of reduced layer has a linear relationship with the reduction time. The optimal conditions for producing RAINBOW samples from PLZT are determined to be 950℃ for 1-1.5 hours. SEM micrograph shows that the RAINBOW ceramics are composed of reduced and unreduced layer obviously. And the reduced layer is transgranularly fractured while the unreduced ceramic is intergranularly fractured. Metallic lead and refractor oxides (PbO, ZrO_2, ZrTiO_4, etc.) are found in the reduced layer by XRD analyses, however, the crystal structure of PLZT is not found. The analysis of the reduction mechanism is in good accordance with experimental data.展开更多
In recent years,industries in the fields of petrochemical,automotive,and aerospace have expressed their interest in utilizing piezoelectric actuators for high-temperature(HT)operations at the temperature above 150℃.H...In recent years,industries in the fields of petrochemical,automotive,and aerospace have expressed their interest in utilizing piezoelectric actuators for high-temperature(HT)operations at the temperature above 150℃.HT piezoelectric ceramics(1x)BiScO_(3-x)PbTiO_(3)(BS-PT)are considered as one of the most competitive piezoelectric actuation materials used in the harsh environment because of its high Curie temperature(T_(C)=450℃)as well as high piezoelectric coefficient(d_(33)=460 pC/N)in the MPB composition.This paper summarized the recent progress in HT piezoelectric ceramics and actuators based on BS-PT solid solutions.The properties of BS-PT piezoelectric ceramics and actuators,including driving mechanisms,actuation performances and their applications in HT environment were also discussed.展开更多
A multilayer piezoelectric actuator, with dimension of 10 mm×10 mm×60 mm, which can output a tensile displacement directly by exploring the d31 effect of piezoelectrics, was fabricated using soft Lead Zircon...A multilayer piezoelectric actuator, with dimension of 10 mm×10 mm×60 mm, which can output a tensile displacement directly by exploring the d31 effect of piezoelectrics, was fabricated using soft Lead Zirconate Titanate(PZT) ceramics. The performance of the actuator was characterized by a special home-made experimental setup under electric fields varying from 200 to 1 000 V/mm with the preload varying from-150 to 100 N at room temperature. Results showed that it can output a maximum tensile displacement of 12 μm under unipolar electric field of 1 000 V/mm and preload was independent with generative displacement in the range of testing preload. Additionally, using the actuator, we built a micro loading apparatus, which can be used to test the fracture behavior of brittle materials.展开更多
Packaged piezoelectric ceramic actuators （PPCAs） and compliant mechanisms are attractive for nanopositioning and nanomanipulation due to their ultra- high precision. The way to create and keep a proper and steady co...Packaged piezoelectric ceramic actuators （PPCAs） and compliant mechanisms are attractive for nanopositioning and nanomanipulation due to their ultra- high precision. The way to create and keep a proper and steady connection between both ends of the PPCA and the compliant mechanism is an essential step to achieve such a high accuracy. The connection status affects the initial position of the terminal moving plate, the positioning accuracy and the dynamic performance of the nanoposi- tioning platform, especially during a long-time or high- frequency positioning procedure. This paper presents a novel external preload mechanism and tests it in a 1-degree of freedom （I-DOF） compliant nanopositioning platform. The 1-DOF platform utilizes a parallelogram guiding mechanism and a parallelogram load mechanism to provide a more accurate actual input displacement and output displacement. The proposed stiffness model simulation results verify the and dynamic model of the platform. The values of the preload displacement, actual input displacement and output displacement can be measured by three capacitive sensors during the whole positioning procedure. The test results show the preload characteristics vary with different types or control modes of the PPCA. Some fitting formulas are derived to describe the preload displacement, actual input displacement and output displacement using the nominal elongation signal of the PPCA. With the identification of the preload characteristics, the actual and comprehensive output characteristics of the PPCA can be obtained by the strain gauge sensor （SGS） embedded in the PPCA.展开更多
基金National Natural Science Foundation of China(Nos.62171285,61971120 and 62327807)。
文摘A hybrid compensation scheme for piezoelectric ceramic actuators(PEAs)is proposed.In the hybrid compensation scheme,the input rate-dependent hysteresis characteristics of the PEAs are compensated.The feedforward controller is a novel input rate-dependent neural network hysteresis inverse model,while the feedback controller is a proportion integration differentiation(PID)controller.In the proposed inverse model,an input ratedependent auxiliary inverse operator(RAIO)and output of the hysteresis construct the expanded input space(EIS)of the inverse model which transforms the hysteresis inverse with multi-valued mapping into single-valued mapping,and the wiping-out,rate-dependent and continuous properties of the RAIO are analyzed in theories.Based on the EIS method,a hysteresis neural network inverse model,namely the dynamic back propagation neural network(DBPNN)model,is established.Moreover,a hybrid compensation scheme for the PEAs is designed to compensate for the hysteresis.Finally,the proposed method,the conventional PID controller and the hybrid controller with the modified input rate-dependent Prandtl-Ishlinskii(MRPI)model are all applied in the experimental platform.Experimental results show that the proposed method has obvious superiorities in the performance of the system.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51472118,51602156,52177072,and 11274174)the Fundamental Research Funds for the Central Universities,China(Grant Nos.30916011104 and 30916011208)
文摘CuO added Pb0.92Sr0.06Ba0.02（Mg1/3Nb2/3）0.25（Ti0.53Zr0.47）0.75O3 ceramics were studied to prepare high-quality multilayer piezoelectric actuators with pure Ag electrodes at 900 ℃. CuO addition not only reduced the sintering temperature significantly from 1260 ℃ to 900 ℃ but also improved the ceramic density to 7.742 g/cm3. The 0.7 wt.% CuO added ceramic sintered at 900 ℃ shows the remnant polarization （Pr） of 40 μC/cm2, 0.28% strain at 40 kV/cm, and the piezoelectric coefficient （d33） of 630 pC/N. This ceramic shows a strong relaxor characteristic with a Curie temperature of 200 ℃. Furthermore, the 0.7 wt.% CuO added ceramic and pure Ag electrodes were co-fired at 900 ℃ to prepare a high-quality multilayer piezoelectric actuator with a d33 of over 450 pC/N per ceramic layer.
文摘Rainbow piezoelectric ceramics are a new type of stress-biased,oxide-reduced composite ferroelectric ceramics,which have a special dome structure.The have shown excellent properties such as ultra-high displacement under an applied electric field and enhanced load-bearing capability.In this article,their manufacture,structures and properties were discussed in detail by combining experiments and theory analysis.The resuts show that the optimal conditions for producing Rainbow samples from PLZT ceramics were determined to be 900℃ for 1 to 1.5 hours.A number of different phases have been found in the reduced layer of Rainbow ceramics by XRD analyses.The phases found include metallic lead and other oxide phases,such as PbO,ZrO 2 and TiO 2.The original PLZT phase was not observed.The reduced layer was transgranularly fractured while the unreduced ceramic was intergranularly fractured.Two kinds of fracture types can be seen at the interface,which denotes the different degrees of reduction.It is shown that the Pb grains (about 0.2μm) constitute a continuous phase in the reduced layer,which accounts for the good electrical conductivity.
基金supported by the National Natural Science Foundation of China(GrantNos.52072150 and 51972146)Shandong Province Key Fundamental Research Program(Grant No.ZR2022ZD39)+1 种基金State Key Laboratory of New Ceramics and Fine Processing,Tsinghua University(Grant No.KF202002)Open Foundation of Guangdong Key Laboratory of Electronic Functional Materials andDevices(Grant No.EFMD2021002Z).
文摘Multilayer ceramic actuator(MLCA)has been widely employed in actuators due to the large cumulative displacement under the low driving voltage.In this work,the MLCA devices consisting of a lead-free MnCO_(3-)and CuO-doped 0.96(K_(0.48)Na_(0.52))(Nb_(0.96)Ta_(0.04))O_(3)-0.04CaZrO_(3) piezoelectric ceramics and a base nickel(Ni)metal inner electrode were well co-fired by the two-step sintering process in a reducing atmosphere.The ceramic layer/electrode interface is well-integrated and clearly continuous without distinct interdiffusion and chemical reaction,which is beneficial to the electrical reliability of the MLCA.As a result,the MLCA laminated with nine active ceramic layers obtains an ultrahigh piezoelectric coefficient d_(33) of 3157 pC/N,about 9 times than bulk ceramics.The 0.5 mm-thick MLCA composed of a series of~50μm-thick ceramic layers and~3μm-thick Ni electrodes reaches a high 1.8μm displacement under the low applied voltage of 200 V(the same displacement requires a voltage as high as 3700 V for~1 mm-thick bulk ceramics).The excellent electrical performance and low-cost base electrode reveal that the(K,Na)NbO_(3)(KNN)-based MLCAs are promising lead-free candidate for actuator application.
文摘Piezoelectric ceramic element (PCE) is a kind of actuator applied widely on the intelligent material & structure. Establishing the relationship between the transferring stress and the controlling signal, namely the transferring and actuating equation, is a key step to analyze the actuating performance of the PCE. Based on the method of the shear lag theory, the procedure of the stress transferring is analyzed and the transferring and actuating model is established in this paper. Some measurements for PCE(PZT5) actuating the Glass Fiber/Epoxy laminate have been done to verify the model established. The experimental results show that the theoretical model agrees well with the practice. Finally, the effect of the main factors on PCE actuating the laminate is studied by using the experimental and theoretical results.
文摘A new type of large-displacement actuating materials called RAINBOW (Reduced and Internally Biased Oxide Wafer) ceramics is fabricated by a chemical reduction of PLZT piezoelectric ceramics. It is found that PLZT is easily reduced and the thickness of reduced layer has a linear relationship with the reduction time. The optimal conditions for producing RAINBOW samples from PLZT are determined to be 950℃ for 1-1.5 hours. SEM micrograph shows that the RAINBOW ceramics are composed of reduced and unreduced layer obviously. And the reduced layer is transgranularly fractured while the unreduced ceramic is intergranularly fractured. Metallic lead and refractor oxides (PbO, ZrO_2, ZrTiO_4, etc.) are found in the reduced layer by XRD analyses, however, the crystal structure of PLZT is not found. The analysis of the reduction mechanism is in good accordance with experimental data.
基金supported by the National Natural Science Foundation of China(Grant Nos.51132001,51072003,11090331,51302163)the Innovational Foundation of Shanghai University(Grant No.K.10-0110-13-009).
文摘In recent years,industries in the fields of petrochemical,automotive,and aerospace have expressed their interest in utilizing piezoelectric actuators for high-temperature(HT)operations at the temperature above 150℃.HT piezoelectric ceramics(1x)BiScO_(3-x)PbTiO_(3)(BS-PT)are considered as one of the most competitive piezoelectric actuation materials used in the harsh environment because of its high Curie temperature(T_(C)=450℃)as well as high piezoelectric coefficient(d_(33)=460 pC/N)in the MPB composition.This paper summarized the recent progress in HT piezoelectric ceramics and actuators based on BS-PT solid solutions.The properties of BS-PT piezoelectric ceramics and actuators,including driving mechanisms,actuation performances and their applications in HT environment were also discussed.
基金Supported by the National Natural Science Foundation of China(11402177)the Research Foundation of Wuhan University
文摘A multilayer piezoelectric actuator, with dimension of 10 mm×10 mm×60 mm, which can output a tensile displacement directly by exploring the d31 effect of piezoelectrics, was fabricated using soft Lead Zirconate Titanate(PZT) ceramics. The performance of the actuator was characterized by a special home-made experimental setup under electric fields varying from 200 to 1 000 V/mm with the preload varying from-150 to 100 N at room temperature. Results showed that it can output a maximum tensile displacement of 12 μm under unipolar electric field of 1 000 V/mm and preload was independent with generative displacement in the range of testing preload. Additionally, using the actuator, we built a micro loading apparatus, which can be used to test the fracture behavior of brittle materials.
基金This research was supported by the National Natural Science Foundation of China （Grant No. 91223201）, the Natural Science Foundation of Guangdong Province （Grant No. S2013030013355）, Project GDUPS （2010） and the Fundamental Research Funds for the Central Universities （Grant No. 2012ZP0004）. These supports are greatly acknowl- edged.
文摘Packaged piezoelectric ceramic actuators （PPCAs） and compliant mechanisms are attractive for nanopositioning and nanomanipulation due to their ultra- high precision. The way to create and keep a proper and steady connection between both ends of the PPCA and the compliant mechanism is an essential step to achieve such a high accuracy. The connection status affects the initial position of the terminal moving plate, the positioning accuracy and the dynamic performance of the nanoposi- tioning platform, especially during a long-time or high- frequency positioning procedure. This paper presents a novel external preload mechanism and tests it in a 1-degree of freedom （I-DOF） compliant nanopositioning platform. The 1-DOF platform utilizes a parallelogram guiding mechanism and a parallelogram load mechanism to provide a more accurate actual input displacement and output displacement. The proposed stiffness model simulation results verify the and dynamic model of the platform. The values of the preload displacement, actual input displacement and output displacement can be measured by three capacitive sensors during the whole positioning procedure. The test results show the preload characteristics vary with different types or control modes of the PPCA. Some fitting formulas are derived to describe the preload displacement, actual input displacement and output displacement using the nominal elongation signal of the PPCA. With the identification of the preload characteristics, the actual and comprehensive output characteristics of the PPCA can be obtained by the strain gauge sensor （SGS） embedded in the PPCA.
