Methodology And Experimental Research Of Inertial Stick-slip Piezoelectric Actuators For Suppressing Backward Motion

The development of high-technology industries such as aerospace,precision electronics,scientific instruments,biomedical engineering,and ultra-precision machining cannot be achieved without the support of precision driving positioning technologies.Compared with electromagnetic driving technology,piezoelectric driving has the advantages of high response speed,high positioning accuracy,small size,and no electromagnetic interference.Among the existing piezoelectric driving principles and technologies,the inertial stick-slip piezoelectric actuator has a large stroke,resolution,and control advantages,which has become an important development direction.However,traditional inertial stick-slip piezoelectric actuators have problems such as backward motion,low speed at low frequency,and poor interchangeability.Addressing the above issues is crucial for enriching the theory of inertial stick-slip piezoelectric actuators and promoting their practicalisation.The main research work in this paper is as follows.Based on the problem of the traditional inertial stick-slip piezoelectric actuator’s backward motion,a flexible beam method is proposed to suppress backward motion,which evolution is elaborated.Then a general dynamics model of the inertial stick-slip piezoelectric actuator is established,which initially verifies the feasibility of the flexible beam for suppressing backward motion.Accordingly,a new inertial stick-slip piezoelectric actuator is designed and tested,which verifies the feasibility of the flexible beam for suppressing backward motion from the experimental point of view.The above method provides a theoretical and experimental basis for the subsequent research.A two-stage lever-amplified inertial stick-slip piezoelectric actuator is proposed for the problem of backward motion and low speed at the low frequency of the inertial stick-slip piezoelectric actuator.The structural design of the two-stage lever flexible driving mechanism is carried out.The influence of the support point and the size of the flexible hinge on the output displacement is simulated and analyzed to verify the feasibility of the two-stage lever amplified inertial stick-slip piezoelectric drive device.According to the above analysis,a prototype was developed.A test system was built to test and analyze output performance,such as stepping characteristics,speed characteristics,and load-carrying capacity.The experimental results show that the twostage lever amplified inertial stick-slip piezoelectric actuator achieves smooth and highspeed motion at low frequency.A replacement strategy of the driving foot is proposed for the inertial stick-slip piezoelectric actuator to address the problems of backward motion,low speed at low frequency,and poor interchangeability.Based on the flexible beam method of suppressing backward motion,a parasitic motion arrangement is adopted to carry out the structural design of the highly interchangeable inertial stick-slip piezoelectric actuator.Moreover,dynamics simulations are employed to reveal the processes of backward motion,smooth motion,and burst motion.Based on the above analysis,a prototype of the highly interchangeable inertial stick-slip piezoelectric actuator was developed.A test system was built to test and analyze the output performance of the stepping,speed,and interchangeability characteristics.The experimental results show that the actuator has good disassembly,assembly repeatability,and high interchangeability.In addition,the evolution of the stepping displacement of the actuator was achieved by changing different types of driving feet,and thus different output performance was obtained.A decoupled,large-stroke scratch test apparatus was designed according to the flexible beam method of suppressing backward motion.Including the structural design of the scratch test apparatus,the design and implementation of the control system,the analysis of the open-loop output and closed-loop control characteristics,and a scratch test study on specular aluminum carried out.In addition,the instrument is compact and suitable for in-situ observation in a strong magnetic field atmosphere or under SEM electron microscopy.In summary,the thesis proposes a method of flexible beams for suppressing backward motion,designs and develops four new inertial stick-slip piezoelectric actuators,and carries out static modeling simulations,dynamics modeling simulations,and output performance testing and analysis of the actuators.The research has enriched the design theory of inertial stick-slip piezoelectric actuators and provided technical support and a strong guarantee for the practical application and promotion of inertial stick-slip piezoelectric actuators in engineering.