Dynamics modeling of a vehicle including piezoelectric actuator

Recent research has focused on energy recovery and storage technologies. One of the materials allowing the recovery of dissipated energy is the piezoelectric material (PE). These functional materials perform reversible energy conversion, transforming electrical energy into mechanical and vice versa. In this study, we investigate the recovery of vibratory energy in vehicle suspension systems—energy traditionally dissipated by conventional shock absorbers—using piezoelectric materials to capture this wasted energy and redirect it to the vehicle’s auxiliary power supply network. We propose an integrated electromechanical model incorporating piezoelectric actuators in parallel with the suspension mechanism. The collected energy is processed and stored for later use in powering accessories such as windows and mirrors. The idea is to integrate renewable energy sources to optimize the performance of the vehicle. We proposed a Multiphysics model of the system under a software used to this type of modeling (Simcenter AMESim v1610_student). The simulation results of the system and its various sub-systems are presented for studying the piezo-actuator response to reduce consumption and increase energy performance in a vehicle. These findings will undergo experimental validation in the project’s subsequent phase.

Smart actuators, made of smart materials, are becoming more attractive in many applications because smart materials are not subjected to wear and does not require lubrication during services. Piezoelectric materials are a group of the many attractive smart materials that are being investigated for many applications today. Piezoelectric materials show fast responses, high efficiency/accuracy and operate on a large bandwidth. Composite materials are of interest because of their design flexibility and because they are lighter than other materials commonly used in aircraft and other applications. For the research reported here, a piezoelectric material was embedded in a composite material to form a piezoelectric composite actuator. This research was conducted to expand our knowledge of piezoelectric composite material actuators, and originated from the need to control air flow separation over an airfoil. There is a need to build a profound knowledge about such actuators before they can be implemented in an airfoil, and to understand which parameters influence the behaviour of piezoelectric composite material actuators under static and dynamic operating conditions. The actuators were manufactured and tested under static and dynamic conditions and the experimental results were compared to the finite element models. The models were incorporated with piezoelectric material properties that were determined experimentally. The results showed that a piezoelectric material’s response to an input stimulant, e.g. electric voltage and frequency, influences the actuator’s behaviour.

Polymer piezoelectric materials polyvinylidene fluoride (PVDF) and its copolymers P(VDF-TRFE) and P(VDF-HFP) are typical organic polymer materials with piezoelectric properties. Currently, these materials attract great attention in academic and application area for their good mechanical properties, corrosion resistance, biocompatibility and easy processing. However, compared with the traditional inorganic piezoelectric ceramic materials, the piezoelectric constant of polymer piezoelectric materials is still relatively low, so improving the piezoelectric properties of such polymer piezoelectric materials has become one of the research hotspots at home and abroad. In this paper, the methods of improving the piezoelectric properties by combining PVDF and its copolymers with different functional materials at national and international levels in recent years are summarized, and the advantages and disadvantages of different types of fillers doped with different polymer piezoelectric materials and their development trends are prospected.

Piezoelectric functional materials have been extensively studied and employed in numerous devices. With the rapid development of modern industries, such as power plants, aerospace, automotive, renewable energy and material processing industries, the high temperature piezoelectric materials that can work in extreme environments are in great demand. Piezoelectric materials including piezoelectric single crystals, ceramics and films, are at the heart of electromechanical actuation and sensing devices. A variety of applications where piezoelectric actuators and sensors operate at elevated temperatures (T 200℃) would be extremely desired. The actuators need to work efficiently with high strokes, torques, and forces while operating under relatively harsh conditions. These include high-temperature fans and turbines, motors for valves or natural gas industries, kiln automation, and actuators for automotive engines such as fuel injectors and cooling system elements. Yet, the majority of industrial actuator applications are at or below the 250℃ temperature limit. In addition to the increase in operational temperatures of piezoelectric motors and actuators, a future area of interest is high-temperature MEMS research, which can be used for high-temperature valving. On the other hand, the piezoelectric sensors have been widely used for structural health monitoring applications. This is due to their wide bandwidth, versatility, simplicity, high rigidity, high stability, high reproducibility, fast response time, wide operating temperature range, insensitivity to electric and magnetic fields, the capacity for miniaturization and minimal dependence on moving parts and low power consumption, and wide piezoelectric materials and mechanisms selections, which will greatly benefit the sensing applications. In addition to the temperature usage range, the piezoelectric sensors must withstand the harsh environments encountered in space, engine, power plants, and also need to possess high sensitivity, resistivity, reliability, stability and robustness. In order to use the piezoelectric materials for a specific high temperature application, many aspects need to be considered together with piezoelectric properties, such as phase transition, thermal aging, thermal expansion, chemical stability, electrical resistivity, and the stability of properties at elevated temperature. In this paper, ferroelectric materials with high Curie point, including perovskite-type ferroelectrics, bismuth layer structured ferroelectrics, tungsten-bronze structured ferroelectrics, together with non-ferroelectric piezoelectric single crystals, are surveyed. The crystal structure characteristics, high temperature piezoelectric properties, and recent research progress are discussed. A series of high temperature piezoelectric devices and their applications are reviewed, including high temperature piezoelectric detectors, sensors, transducers, actuators, etc. Finally, recent important research topics, the future development of high temperature piezoelectric materials and the potential new applications are summarized.

The present article reports the feasibility of the electrical energy generation from ambient low-frequency vibration using a piezoelectric material mounted on a bimorph cantilever beam actuator. A corresponding higher-order analytical model is developed using MATLAB in conjunction with finite element method under low-frequency with both damped and undamped conditions. An alternate model is also developed to check the material and dimensional viability of both piezoelectric materials (mainly focussed to PVDF and PZT) and the base material. Also, Genetic Algorithm is implemented to find the optimum dimensions which can produce the higher values of voltage at low-frequency frequencies (≤ 100 Hz). The delamination constraints are employed to avoid inter-laminar stresses and to increase the fracture toughness. The delamination has been done using a Teflon sheet sandwiched in between base plates and the piezo material is stuck to the base plate using adhesives. The analytical model is tested for both homogenous and isotropic material characteristics of the base material and extended to investigate the effect of the different geometrical parameters (base plate dimensions, piezo layer dimensions and placement, delamination thickness and placement, excitation frequency) on the model responses of the bimorph cantilever beam. It has been observed that when the base material characteristics are homogenous, the efficiency of the model remains higher when compared to the condition when it is of isotropic material. The necessary convergence behaviour of the current numerical model has been established and checked for the accuracy by comparing with available published results. Finally, using the results obtained from the model, a prototype is fabricated for the experimental validation via a suitable circuit considering Glass fibre and Aluminium as the bimorph material.

Studies on muscle mimicking piezo-composite actuators have been increased during the last two decade due to the possibility of various applications for compact lightweight actuators of small unmanned aircraft and biomimetic robots. Piezoelectric materials have been used in a variety of application ranging from shape control of structure, active vibration control of structure to noise suppression due to compact size and good frequency response. The conventional poly-crystal piezoelectric ceramic materials, however, have rather low actuating strains and displacement. In this paper, design and fabrication methods of actuator with single crystal piezoelectric material were investigated to increase actuation strain and displacement.

The suspension system of a vehicle provides the means by which forces and movements are transferred from the body to the wheels and vice versa. While the general outline of vehicle suspension behavior is fairly well known, little interest has been shown in the detailed dynamic performance of the various components. Air springs are perhaps the most versatile and adaptable type of suspension element. They provide practically frictionless action, adjustable load capacity and simplicity of height control. Initially, a vehicle suspension system with a pneumatic isolator connected to a fixed volume tank via parallel plate restrictor is considered. Here the damping is provided by the flow of air through the restricted passage which has an advantage over the conventional viscous shock absorber. Body movements are only considered to be vertical harmonic displacement. An optimization technique is applied to evaluate the optimum values of many parameters involved for which the maximum transmitted motion to the body would be minimum over the broad frequency range. Theoretical expressions for the transmissibility of the body and the wheel, optimum values of mass ratio, stiffness ratio and damping ratio are presented. Design data are presented nondimensionally for parameter variations which are sufficiently broad to encompass a wide range of practical engineering problems.

The piezoelectric actuating device that consist of piezoelectric material is known for large power density with simple structure. It can generate large force than the conventional actuator and it has also wide bandwidth with fast response in a compact size. To control the piezoelectric actuator, we need analog signal conditioning circuit as well as digital microcontrollers. Conventional microcontrollers are not equipped with analog part and need digital to analog converters in addition to the embedded analog to digital converters, which makes the system bulky compared with the small size of the piezoelectric devices. To overcome these weaknesses, we are developing single-chip controller that can handle analog and digital signals simultaneously using mixed signal FPGA technology. We used the Smart Fusion FPGA device that integrates ARM®Cortex-M3, analog interface and FPGA fabric in a single chip and offering full customization. It gives more flexibility than traditional fixed-function microcontrollers with the excessive cost of soft processor cores on traditional FPGAs. In this paper we introduce the design of a single chip controller using mixed signal FPGA, Smart Fusion device. To demonstrate its performance, we implemented a PID controller and PWM generator in the FPGA fabric. PWM generator and PID controller showed the effective regulation of a simple 1st order plant.

The present research article aims to describe that the flexoelectric affects the propagation of Love-type in various piezoelectric (PE) materials bars (PZT-7A, PZT-5A, PZT-6B, PZT-4, PZT-2) that rest over a silicon oxide plate under the presence of a deformed interface. With the help of material properties of these various piezoelectric, this article elucidates the impact of flexoelectric (FE) and piezoelectric (PE) on propagation characteristics of Love-type waves. Before this, the desire dispersion relation in the form of a complex, for both electrically unlocked/locked conditions, have been obtained by using mechanical as well as electrical quantities for the respective medium under suitable boundary and interface conditions. The complex dispersion relation is separated into real and imaginary terms which give Real(c) and Imag(c). Further, the effect of flexoelectric (FE) and piezoelectric (PE) on Real(c) and Imag(c) have been observed. In addition, a comparative study among various types of piezoelectric materials is also performed which serve as a major highlight of the present research work. The outcomes of this study may be very helpful in the specific problems of monitoring structural health system design with the help of simulation and a lesser number of elaborate trials.

A three-dimensional boundary element methodology to study frictionless indentation response of piezoelectric (PE) materials is presented. The boundary element method (BEM) is used in order to compute the electro-elastic influence coeffcients of fully anisotropic piezoelectric solids. The proposed contact formulation is based on the augmented Lagrangian method presented in [33, 34, 35] and makes it possible to consider piezoelectric materials under different mechanical and electrical boundary conditions (i.e. insulating indenter and conducting indenter). The methodology is validated by comparison with theoretical solutions presented in the literature.

Using piezoelectric elements to harvest energy from ambient vibrations has been of great interest over the past few years. Due to the relatively low power output of piezoelectric materials, there are many study to improve the energy harvesting efficiencies. This paper is study the efficiencies of the output energy considering the cantilever piezoelectric bimorph using aluminum vibration beam. when the length of vibration beam and the piezoelectric body becomes same and the maximum output power comes out. DC voltage was increased as the beam thickness and vibration frequency was increased. The vibration beam was able to achieve very large energy value.

Performance improvement of flexible piezoelectric energy harvester for irregular human motion with energy extraction enhancement circuit

Active vibration control of a smart FG (functionally graded) cylindrical shell conveying fluid in thermal environment is studied theoretically by using a laminated piezoelectric actuator. Velocity feedback control law is implemented to activate the piezoelectric actuator. Considering the electric-thermo-fluid-structure interaction effect, a nonlinear dynamic model of the smart fluid-conveying FG cylindrical shell is developed based on Hamilton’s principle and von-Karman type geometrical nonlinear relationship. The inviscid, incompressible, isentropic and irrotational fluid is coupled into governing equations using the linearized potential theory. The Galerkin’s method is used to obtain the nonlinear governing equations of motion of the coupled system. The multiple time scales approach is applied to solve the resulting governing equations for analysing the nonlinear dynamic characteristics of the coupled system. The influence of fluid flow velocity, feedback control gains of piezoelectric voltage, external excitation and material properties of FGM on the frequency-response curves of system are investigated. The results indicate that the piezoelectric voltage is an effective controlling parameter for vibration control of the system, and the flow velocity can effect significantly the vibration amplitude and nonlinearity of the coupled system.

The primary focus of this research is to develop a tool using semi-precious metals and quartz for preventing or eliminating wax deposition in production and transport system. It also focuses on explaining the mechanisms of using piezoelectric energy generated from mixtures of semi-precious metals and quartz to prevent wax deposition. Five samples of waxy crude were sourced from Niger Delta and characterized for the purpose of this experiment. Quartz was sourced from Bauchi State of Nigeria while two semi-precious metals, zinc and lead sourced from Jos Metallurgical Development Centre, Plateau State of Nigeria were used. The metals were grounded to smaller sizes and mixed with the quartz. Molten aluminium was used to fabricate the tool. The tool was then fixed into the flow line. Each of the crude samples was flown through the flow system under reduced temperature and pressure (below its wax appearance temperature) and the quantity of wax deposited was recorded before the tool and after the tool. The results show that immediately after the condenser, higher percentage of wax deposit was recorded but as the fluid pass through the fabricated tool the quantity of deposits reduced drastically. This is an indication of effectiveness of the fabricated tool in preventing wax deposits along the flow lines. It was also noticed that the effectiveness is more pronounced with zinc plus quartz crystal with over 32% success in achieving deposit reduction on the most potential problematic crude sample while lead achieved only 17.9% success on the same sample. Key words: Piezoelectric material, piezoelectric energy, semi-precious metals, wax appearance temperature, wax deposition.

A comparison between actively-controlled piezoelectric (PZT) material with positive position feedback (PPF) and a parallel resistor-inductor shunt circuit technique is provided. This study focuses on the performance of each technique at reducing structural vibration on a test plate for both narrowband and broadband frequency reductions. The comparison between the shunted and active PZT damping techniques used in this study shows that active control with positive position feedback was more effective at controlling vibrations of a test plate. The active PZT method was able to add damping to each of the modes targeted in the frequency range of interest. In addition, active control with positive position feedback was able to achieve this level of control authority with a single PZT patch located in the center of the test plate. Conversely, shunted PZTs used three PZT actuators to reduce the test plate vibrations. The results show that actively-controlled PZTs can provide much more damping per square area of PZT than shunted PZTs, by as much as four times more.