Search

Microgel-enhanced asymmetric hydrogels containing a thermosensitive layer and a non-thermosensitive layer are constructed. Actuators exhibiting outstanding response properties and multiple mechanosensors possessing high sensitivity are demonstrated. [Display omitted] Thermosensitive hydrogels have found extensive applications in soft devices, but they often suffer from limited functionalities, low response rate and small response amplitude. In this work, double layered asymmetrical hydrogels composed of a thermosensitive layer and a non-thermosensitive layer are developed to simultaneously achieve high-performance mechanosensing and actuating properties in a single hydrogel. In thermosensitive layer, thermosensitive microgels are introduced to construct hierarchical structure, which accounts for the enhanced thermosensitive behaviors by cooperative responsiveness. In non-thermosensitive layer, poly(acrylamide- co -acrylic acid) (P(AM- co -AA)) hydrogel is constructed. KCl is introduced as conductive component. Mechanosensors for monitoring various mechanical stimuli in daily life have been fabricated utilizing such hydrogels and high gauge factors (GF) have been achieved, 0.38 for resistive strain sensors, 9.40 kPa−1 for piezoresistive pressure sensors and 3.92 kPa−1 for capacitive pressure sensors. Because of the asymmetrical structure, such hydrogels also exhibit outstanding actuating properties with a fast response rate of 863°/min and a bending amplitude about 360°. Interestingly, grasping-releasing of target objects utilizing an octopus-shaped hydrogel actuator and temperature alerting based on hydrogel actuator are also demonstrated. Overall, the double layered asymmetrical ionic hydrogels have provided a new clue to construct hydrogel devices with multiple functionalities and enhanced response properties. [ABSTRACT FROM AUTHOR]

The effect of adding texture to increase the deformation of a bilayer actuator by a factor of over 100 was demonstrated. A bilayer actuator is driven by the difference in thermal deformation. Therefore, two films or plates with a large difference in thermal expansion coefficient are required. The newly developed textured film actuator (TFA) obtained large deformation even in a case involving a combination of two films with a small difference in thermal expansion coefficient. The TFA was fabricated by transferring the texture when laminating two PI films with different coefficients of thermal expansion. A TFA with thin‐film electrodes was heated by applying electric power. Thereby, it unfolded from a curled state. The maximum generated force and curvature of the TFA were 7.4 mN and 0.19 mm−1, respectively, at 0.38 W. The manufacturing process for the TFA is simple and convenient, as it does not require adhesives or special materials. In thermal drive bilayer actuator fabrication, the range of material selection is expanded substantially. In addition, large deformations are generated with less energy. Therefore, the energy consumption is likely to be reduced. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Poly(ionic liquid) (PIL)‐based porous membranes are extensively investigated as soft polymer actuators. While PILs have shown significant advancements in membrane fabrication and stabilization of metal nanoparticles (MNPs), research on integrating MNPs into porous membranes to achieve actuation behavior under multiple stimuli is limited. Herein, this work presents a new paradigm for designing a porous PIL‐polyacrylic acid (PAA) membrane with a distinct MNP gradient via a top‐bottom diffusion approach involving a metal salt precursor solution and NaBH4 as a reducing agent. The strong binding sites provided by PILs, combined with the gradient distribution of ‐COO− groups across the membrane cross‐section, play a significant role in controlling the MNPs' gradient distribution. Interestingly, the MNPs within the membrane display excellent catalytic activity in exothermic reactions such as H2O2 decomposition, dissipating uneven heat that quickly permeates the membrane network. This induces asymmetrical swelling of polymer chains, resulting in rapid membrane bending. Furthermore, such MNP‐loaded membrane could serve as a portable test paper for visually monitoring H2O2. This advancement paves the way for the development of intricate smart actuation materials and expands their practical applications in various real‐life scenarios. [ABSTRACT FROM AUTHOR]

Inorganic nanoparticles have been widely used as fillers to modify dielectric elastomers to simultaneously improve mechanical and dielectric performances. Elegant interface design is crucial for achieving synergy between fillers and elastomers. Herein, we show that diborate ester polymers can both improve the interfacial compatibility between inorganic nanoparticles and elastomers and enhance the dielectric performances. The diborate ester polymers are derived from the condensation reaction between tetrakis(dimethylamino)diborane (or tetrahydroxydiborane) and a three‐armed catechol monomer. Choosing TiO2 nanoparticles as the inner core, a series of TiO2@diborate ester polymer core‐shell nanoparticles are synthesized. Density functional theory (DFT) calculations indicate that the diborate ester polymer shell tightly bonds to the surface of TiO2 through two dissociative bidentate bridging modes of the catechol monomer (absorption energy: −11.049 eV). These core‐shell nanoparticles can soften and tough polydimethylsiloxane (PDMS) and show enhanced interfacial binding affinity to PDMS than naked TiO2 nanoparticles. The fabricated composites have high dielectric constants (up to 6.8) and low dielectric losses (<0.03). The actuated strain and puncture voltage of the composites reach 25.9% and 80 V μm−1, respectively, which are much higher than those of PDMS and TiO2/PDMS. This work provides a promising route to fabricate core‐shell nanoparticles for high‐performance dielectric elastomers. [ABSTRACT FROM AUTHOR]

Electronic textiles (E‐textiles) are made using various materials including carbon nanotubes, graphene, and graphene oxide. Among the materials here, e‐textiles are fabricated with reduced graphene oxide (rGO) coating on commercial textiles. rGO‐based yarns are prepared for e‐textiles by a simple dip coating method with subsequent non‐toxic reduction. To enhance the conductivity, the rGO yarns are coated with poly(3,4‐ethylene dioxythiophene): poly(styrenesulfonic acid) (PEDOT) followed by electrochemical polymerization of polypyrrole (PPy) as the electromechanically active layer, resulting in textile actuators. The rGO‐based yarn actuators are characterized in terms of both isotonic displacement and isometric developed forces, as well as electron microscopy and resistance measurements. Furthermore, it is demonstrated that both viscose rotor spun (VR) and viscose multifilament (VM) yarns can be used for yarn actuators. The resulting VM‐based yarn actuators exhibit high strain (0.58%) in NaDBS electrolytes. These conducting yarns can also be integrated into textiles and fabrics of various forms to create smart e‐textiles and wearable devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Gel actuators are a kind of soft intelligent material that can convert external stimuli into deformations to generate mechanical responses. The development of gel actuators with advanced structures to integrate multiple responsiveness, programmability, and fast deformation ability is urgently needed. Here, we explored a poly(7-(2-methacryloyloxyethoxy)-4-methylcoumarin- co -acrylic acid- co -glycol) ternary gel network as an actuator with reprogrammable photo/H 2 O dual responsibilities. In such a design, [2 + 2] photodimerization and photocleavage reactions of coumarin moieties can be realized under 365 and 254 nm light irradiation, respectively, affording reversible photodriven behaviour of the gels. The abundant carboxylic acid in the backbone has the capacity to form additional crosslinks to assist and accelerate the photodriven behaviour. The incorporation and orientation of halloysite nanotubes (HNTs) in gel matrices support an axial direction force and result in a more controllable and programmable actuating behaviour. The synergistic response enables fast grasping-releasing of 5-times the weight of the object in water within 10 min by fabricating HNT-incorporated gels as a four-arm gripper. [ABSTRACT FROM AUTHOR]

This paper proposes an improved actuator system model for UAV elevators using multibody dynamics simulation. The multibody dynamics simulation employs the Simscape Multibody, module in MATLAB coupled with Simulink to model the servo and hinge moment calculation. The actuator system comprises an electrical servo and mechanical components, including arms, push rods, horns, and the elevator. The electrical servo is modeled using a PID controller and a simplified motor model. The multibody dynamics simulation is employed to capture the dynamics of the mechanical components, coupled with the electrical servo through torque delivery to the mechanical components. The simulation is applied to the elevator of a medium altitude long endurance (MALE) UAV with a Maximum Take Off Weight of 1300 Kg. Generating these quantities provide a benefit in capturing the operational envelope of the servo to be compared to its limitations. Given the features of this simulation, it is proposed to extend the research by integrating this method with flight dynamics simulation. [ABSTRACT FROM AUTHOR]

Linearity is an important factor that affects actuator accuracy. However, the high nonlinearity of KNN piezoelectric ceramics restricts their application in actuators. In this study, we used grinding stress to improve the linearity of ceramic chips, and used them to fabricate a laminated actuator. The ceramic sheets were ground to a thickness of 0.5 mm. During grinding, some areas of the ceramic changed from tetragonal to orthorhombic, owing to the grinding stress. The piezoelectric constant (d33) increased from 198 to 268 pC/N. Notably, the linearity of the ceramics improved. Seven pieces of ground ceramics were bound, to fabricate a laminated multilayer actuator with a total thickness of 3.5 mm. A DC voltage was applied to the actuator, and the displacement was measured. The displacement reached 0.73 μm under a low driving voltage of 200 V. A linear regression analysis of the displacement–voltage relationship was performed, obtaining the regression equation of the actuator. The linearity correlation coefficient was approximately 0.9903, implying that the actuator exhibits a high accuracy. The grinding stress improved the linearity, together with the piezoelectric properties of the ceramic chips, thus improving the actuator accuracy. This research will promote the application of KNN piezoelectric ceramics in actuators. [ABSTRACT FROM AUTHOR]

Detuning errors limit the accuracy of phase extraction in phase-shifting interferometry (PSI). To improve this accuracy, the systems to control the phase shifter dispositive must be highly accurate, involving high technology, exhaustive calibration, high cost, and constant maintenance. This manuscript presents a method for improving the accuracy of the phase step generated at the Fourier plane by rotating and displacing the grating in a double-aperture common-path interferometer. It is demonstrated that both the detuning errors and the phase extraction uncertainty decrease with the grating rotation angle. The experimental implementation is very simple, as it does not require any sophisticated mechanical system to improve the accuracy, no exhaustive calibration, and no additional mechanical and optical dispositive. With the present approach, the PSI method could be achieved very simply and with high accuracy by using a low-accuracy actuator. The theoretical model and experimental results are presented to demonstrate the present proposal. [ABSTRACT FROM AUTHOR]

There is a growing interest in creating biomimetic actuators that can perform human‐like actions in response to external stimuli. Despite the significant advancements in soft actuators, using high‐energy UV light in photoresponsive actuators remains a great challenge. Herein, we develop a film composed of polyvinyl alcohol and photo responsive Disperse Red 1 (PVA/DR1) that actuate in response to visible light. The photoresponsive film starts to actuate in the presence of green light due to trans→cis isomerization of photoresponsive dye. The actuation response of the films was investigated by varying concentrations of DR1 dye and the intensity of green light. Based on these features, we demonstrated a four‐arm soft‐gripper that can mimic human‐hand‐like motions in response to green light. This kind of actuator may find potential applications in soft robotics and biomimetic microgrippers. [ABSTRACT FROM AUTHOR]

The paper presents the motivations for the application of actively controlled elements in the running gear of a rail vehicle and the challenges that need to be addressed before deploying vehicles with actively controlled elements in real operation. Furthermore, the paper presents the design of an active element concept and its control for steering the axles of an urban rail vehicle to improve the vehicle's passage through small radius curves. The design takes into account the fundamental issues of cost and safety of the application of active elements, which are addressed in the presented control design by using data from autonomous driving subsystems such as the environmental database or the anti-collision system. [ABSTRACT FROM AUTHOR]

Recently, an increasing number of electromagnetic devices have been using smart fluids. These include ferrofluids, electrorheological fluids, and magnetorheological (MR) fluids. In the paper, magnetorheological fluids are considered for use in a spherical actuator for haptic applications. An approach is presented to the design and optimization of such a device, using finite element method modelling linked with differential evolution (DE). Much consideration was given to the construction of the objective function to be minimized. A novel approach to objective function assembly was used, using reference values based on the model design and created with parameters set to the midpoint values of the selected range. It was found to be a useful strategy when the reference values are unknown. There were four parameters to be optimized. Three of them gravitated towards the boundary value, and the fourth (actuator radius) was somewhere in between. The value of the objective function reached a minimum in the range of actuator radius between 42.9880 mm and 45.0831 mm, which is about a 5% difference in regard to the actuator radius. Three passes of optimization were performed with similar results, proving the robustness of the algorithm. [ABSTRACT FROM AUTHOR]

A Pb(Ni1/3Nb2/3)0.5(Ti0.7Zr0.3)0.5O3 functionally graded piezoelectric actuator was fabricated by tape-casting. The properties of the PNN-PZT ceramics were initially investigated by phase and microstructure analyses. High piezoelectric, dielectric and ferroelectric properties of d33 = 780 pC/N, kp = 0.605, εr = 6.18 × 103, tanδ = 0.018, Pr = 26.36 μC/cm2 were obtained for the specimens sintered at 1225 °C. The new piezoelectric actuator consisted of four layers, and the variation of changes in their d33 and εr were graded opposite the thickness direction. The relationship between displacement and voltage for the actuator was determined, with the results showing that it was linear. The driving displacement of the actuator reached 416.550 μm. [ABSTRACT FROM AUTHOR]

Haptics applications are receiving increasing attention in entertainment, medical support systems, and various industries. Three-dimensional (3D) haptics is important to provide users real experiences. Conventional haptic devices consist of many motors and mechanical elements grounded in an environment. Therefore, they are large in size and heavy. Haptic devices using asymmetric vibrations can display illusion forces with mobile structures. However, they need additional structures (comprising actuators) to generate a 3D illusion force; however, the operational mechanism becomes complex. To solve this problem, we propose the use of a 3-degree-of-freedom (3DOF) oscillatory actuator that can generate a 3DOF vibration using only one actuator. This study describes the basic characteristics and operating verification of the 3DOF oscillatory actuator. The static thrust characteristics are quantified and analyzed using a finite element method. The dynamics are calculated based on numerical simulations using a dynamic model. The prototype's experimental results show that the 3DOF actuator can generate 3DOF vibration. [ABSTRACT FROM AUTHOR]

Saving energy from domestic appliances is a focus in the effort to combat energy challenges. Linear compressors are a more efficient alternative to the traditional compressors used in refrigerators, which account for 20–40% of all residential electricity use. This article investigates the new topology of the moving magnet (MM), dual-stator single-mover linear oscillating actuator (DSSM-LOA) for linear compressor application. Both the stators were C-shaped, with coils looped across their end sides. Two permanent magnets (PMs) that were axially magnetized were housed on the mover. The PM structural shape significantly affected its fabrication cost and magnitude of magnetic flux density ( B ). The DSSM-LOA makes use of axially magnetized rectangular-shaped PMs because they are inexpensive and generate high electromagnetic (EM) force density. End ferromagnetic core materials were used to improve the magnetic flux, linking from the stator to the mover. All the design parameters were optimized through parametric analysis using the finite parametric sweep method. Parameters present within the three primary parameters (length, height, and depth) that were assumed constants were optimized, and the optimal dimensions were selected based on the EM force. The investigated DSSM-LOA was contrasted with traditional LOA designs, and they showed significant improvement in EM force per ampere, generally named motor constant (MC), MC per PM mass, MC density, cogging force, and stroke. Additionally, the proposed DSSM-LOA had a simple structure and low cost, and it operated in a feasible range of strokes for linear compressor application. [ABSTRACT FROM AUTHOR]

The unique drive principle and strong manipulation ability of spider legs have led to several bionic robot designs. However, some parameters of bionic actuators still need to be improved, such as torque. Inspired by the hydraulic drive principle of spider legs, this paper describes the design of a bionic actuator characterized by the use of air pressure on each surface and its transmittance in the direction of movement, achieving a torque amplification effect. The produced torque is as high as 4.78 N m. In addition, its torque characteristics during folding motions are similar to those during unfolding motions, showing that the bionic actuator has stable bidirectional drive capability. [ABSTRACT FROM AUTHOR]

Shape memory polymer (SMP) can store entropic energy during programming and release the energy as recovery. The released energy is determined by the recovery strain and the recovery stress. The low recovery stress of SMP limits its application. In this paper, shape memory nanocomposite fibers (SMNFs) prepared by wet spinning through a two‐step orientating process show thermo‐active and water‐driven shape memory effect. Carbon nanotubes (CNTs) are uniformly dispersed in SMNF and aligned along the SMNF axis. SMNF with 13 wt% CNT has an average maximum recovery stress of ~160 MPa at 100°C, which is almost five times higher than that of a pure PVA fiber. The uniform distribution of the orientational CNTs in the SMNFs and the confinement effect of the CNTs confirmed by the increased relaxation time contribute to the increment of the recovery stress. Aligned CNTs impede the mobility of amorphous chains and increase the Tg of SMNFs. The twisted SMNF can drive an object up to 25 times its own weight in water to rotate and lift. The rotational velocity of the twisted SMNF is sensitive to temperature. Water molecules acting as plasticizers greatly enhance the mobility of the PVA chains, and the SMNF in water releases the stored entropic energy at room temperature. The SMNF with high recovery stress demonstrates its potential for applications in the field of actuators and artificial muscles. [ABSTRACT FROM AUTHOR]

Currently, the preparation of actuators based on ionic electroactive polymers with a fast response is considered an urgent topic. In this article, a new approach to activate polyvinyl alcohol (PVA) hydrogels by applying an AC voltage is proposed. The suggested approach involves an activation mechanism in which the PVA hydrogel-based actuators undergo extension/contraction (swelling/shrinking) cycles due to the local vibration of the ions. The vibration does not cause movement towards the electrodes but results in hydrogel heating, transforming the water molecules into a gaseous state and causing the actuator to swell. Two types of linear actuators based on PVA hydrogels were prepared, using two types of reinforcement for the elastomeric shell (spiral weave and fabric woven braided mesh). The extension/contraction of the actuators, activation time, and efficiency were studied, considering the PVA content, applied voltage, frequency, and load. It was found that the overall extension of the spiral weave-reinforced actuators under a load of ~20 kPa can reach more than 60%, with an activation time of ~3 s by applying an AC voltage of 200 V and a frequency of 500 Hz. Conversely, the overall contraction of the actuators reinforced by fabric woven braided mesh under the same conditions can reach more than 20%, with an activation time of ~3 s. Moreover, the activation force (swelling load) of the PVA hydrogels can reach up to 297 kPa. The developed actuators have broad applications in medicine, soft robotics, the aerospace industry, and artificial muscles. [ABSTRACT FROM AUTHOR]

Photo‐responsive liquid crystal elastomer (LCE) actuator is of paramount significance for emerging applications in soft robotics, biomimetic devices, and adaptive optical devices. However, to achieve circularly polarized light‐driven LCE actuator, which can provide an additional degree of freedom of light in the control method, is still a challenge. Herein, a circularly polarized light‐driven LCE actuator is demonstrated. The actuator is fabricated by bonding a cholesteric liquid crystal (CLC) film, which is capable of selectively reflecting and transmitting circularly polarized light, with a photothermal agent doped LCE film in splay configuration as a bilayer structure. An electrically controlled optical system with a fast switching ability of circularly polarized light's handedness has been developed to study the circularly polarized light‐response bending property of the proposed actuator under various periodic driven voltage schemes. A crawler driven by circularly polarized light based on CLC‐LCE actuator is demonstrated experimentally with different moving modes. The application of circularly polarized light in the LCE actuator driving provides an additional controlling degree of freedom for photo‐responsive LCE actuators besides the wavelength, spatial distribution, and linear polarization of light, showing wide application prospects in soft robotics, biomimetic technologies, and adaptive optical devices. [ABSTRACT FROM AUTHOR]

In the paper the results of research on an ultra-fast actuator with high initial energy were presented. The purpose of this research is to determine the critical parameters of a copper coil and a double-layer disc based on magneto-thermal analysis. The determined parameters must ensure the expected dynamics of the moving disc while not exceeding the allowable coil and disc temperature. [ABSTRACT FROM AUTHOR]

In the field of intelligent drive and sense, the traditional actuator can realize linear actuation and lacks sensing function. Therefore, a new sensing actuator is designed, which can not only output force and displacement, but also have thrust anti-torque sensing function. Firstly, the model of piezoelectric actuator is designed, and the geometric and mechanical models are established. Furthermore, the geometric relationship of mechanical and electrical parameters is analyzed. Secondly, the optimal included angles are determined after finite element analysis and optimization. Finally, the maximum output displacement is obtained through finite element analysis, and the maximum strain position is pointed out. Besides, the rotational stiffness is obtained. The results show that the modeling method and simulation results are accurate. [ABSTRACT FROM AUTHOR]

This paper aims at finding an optimal design of a shape memory alloy (SMA) actuator that guarantees a required reliability level under uncertainties parameters. The SMA actuator is composed of two NiTi membranes which, at room temperature, are in a martensitic state. They have an initial at shape and are bonded together with an intermediate spacer. The motion of the actuator is caused by the heating or cooling of its membranes. This paper proposes a methodology to find the best adjustment between cost and safety. Accordingly, several methods are developed, such as the hybrid method (HM) and the robust HM (RHM) to reach this purpose. The objective of this work is to present an extension of these methods in case of the SMA material. In fact, in this case, these methods may lead to an infeasible solution. Then, a method called improved RHM (IRHM) is proposed to overcome the difficulties of other ones. The obtained results showed the effectiveness and efficiency of the IRHM for treating the reliability-based design optimization problem of the SMA actuator. [ABSTRACT FROM AUTHOR]

Soft actuators that execute diverse motions have recently been proposed to improve the usability of soft robots. Nature-inspired actuators, in particular, are emerging as a means of accomplishing efficient motions based on the flexibility of natural creatures. In this research, we present an actuator capable of executing multi-degree-of-freedom motions that mimics the movement of an elephant's trunk. Shape memory alloys (SMAs) that actively react to external stimuli were integrated into actuators constructed of soft polymers to imitate the flexible body and muscles of an elephant's trunk. The amount of electrical current provided to each SMA was adjusted for each channel to achieve the curving motion of the elephant's trunk, and the deformation characteristics were observed by varying the quantity of current supplied to each SMA. It was feasible to stably lift and lower a cup filled with water by using the operation of wrapping and lifting objects, as well as effectively performing the lifting task of surrounding household items of varying weights and forms. The designed actuator is a soft gripper that incorporates a flexible polymer and an SMA to imitate the flexible and efficient gripping action of an elephant trunk, and its fundamental technology is expected to be used as a safety-enhancing gripper that requires environmental adaptation. [ABSTRACT FROM AUTHOR]

Multifunctionality is important to the development of next-generation actuators and intelligent robots. However, current multi-functional actuating systems are achieved based on the integration of diverse functional units with complex design, especially lacking in multi-mode sensing and displaying functions. Herein, a light-driven actuator integrated with self-powered/visual dual-mode sensing functions and rewritable display function is proposed. The actuator demonstrates a bending curvature of 0.93 cm-1 under near-infrared light irradiation. Meanwhile, by embedding a pencil-drawn graphite generator and thermochromic materials, the actuator also provides two independent sensing functions. First, owing to the photo-thermoelectric effect of graphite, the actuator spontaneously outputs a self-powered voltage (Seebeck coefficient: 23 μV K-1), which can reflect the deformation trend of actuator. Second, color changes occur on the actuator during deformation, which provide a visual sensing due to the thermochromic property. Furthermore, the actuator can be utilized as a rewritable display, owing to the integrated color-memorizing component. Intelligent robots, switches, and smart homes are further demonstrated as applications. All of them can spontaneously provide self-powered and visual sensing signals to demonstrate the working states of actuating systems, accompanied by rewritable displays on the actuators. This study will open a new direction for self-powered devices, multi-functional actuators, and intelligent robots. [ABSTRACT FROM AUTHOR]

PVC gels are gaining more attention in the applications of soft actuators. While their characteristics have been extensively studied experimentally, precise models that predict the deformation due to imposed mechanical and electrical forces are not yet available. In this work, a viscoelastic model based on a combination of a Maxwell and a Kelvin–Voigt model is developed to describe the responsive deformation of the actuator. The model parameters are tuned using data obtained from a unique experimental setup. The PVC gel used in the actuator is made from PVC and dibutyl adipate (DBA) together with a tetrahydrofuran (THF) solvent. A full factorial test campaign with four and three levels for the mechanical and electrical forces, respectively, are considered. The results showed that some of the viscoelastic response could be captured by the model to some extent but, furthermore, the stiffness behavior of the PVC gel seemed to be load-type-dependent, meaning that the PVC-gel material changed stiffness due to the magnitude of the electrical force applied and this change was not equal to a similar change in mechanical force. [ABSTRACT FROM AUTHOR]

Regarding the global energy crisis, it is of profound significance to develop spontaneous power generators that harvest natural energy. Fabricating humidity‐responsive actuators that can conduct such energy transduction is of paramount importance. Herein, we incorporate covalent organic frameworks with flexible polyethylene glycol to fabricate rigid‐flexible coupled membrane actuators. This strategy significantly improves the mechanical properties and humidity‐responsive performance of the actuators, meanwhile, the existence of ordered structures enables us to unveil the actuation mechanism. These high‐performance actuators can achieve various actuation applications and exhibit interesting self‐oscillation behavior above a water surface. Finally, after being coupled with a piezoelectric film, the bilayer device can spontaneously output electricity over 2 days. This work paves a new avenue to fabricate rigid‐flexible coupled actuators for self‐sustained energy transduction. [ABSTRACT FROM AUTHOR]

Regarding the global energy crisis, it is of profound significance to develop spontaneous power generators that harvest natural energy. Fabricating humidity‐responsive actuators that can conduct such energy transduction is of paramount importance. Herein, we incorporate covalent organic frameworks with flexible polyethylene glycol to fabricate rigid‐flexible coupled membrane actuators. This strategy significantly improves the mechanical properties and humidity‐responsive performance of the actuators, meanwhile, the existence of ordered structures enables us to unveil the actuation mechanism. These high‐performance actuators can achieve various actuation applications and exhibit interesting self‐oscillation behavior above a water surface. Finally, after being coupled with a piezoelectric film, the bilayer device can spontaneously output electricity over 2 days. This work paves a new avenue to fabricate rigid‐flexible coupled actuators for self‐sustained energy transduction. [ABSTRACT FROM AUTHOR]

Hydrogen power sources are expected to be the main power source for a sustainable society in the future. Therefore, the development of mechanical parts or systems to adapt to the usage of hydrogen is a key issue. Ionic polymer metal composite (IPMC) actuators are composed of an electrolyte polymer membrane coated with electrodes. Owing to their light weight, flexibility, and ease of miniaturization, IPMC actuators are promising candidates for use as micro-actuators in small robots, microvalves, or artificial muscles. In this study, a hydrogen-assisted IPMC actuator is developed, and its deformation mechanism is investigated. The hydrogen absorption produced by water splitting and the hydrated cation movement in the electrolyte are the driving forces involved in this actuator. The effects of applied voltage, thickness of palladium electrodes, and length of the actuators are studied. Moreover, the contributions of bending moments by a hydrated cation movement and those by hydrogen absorption to the bending deformation are separately clarified. The results indicate that the deformation mechanism of the hydrogen-assisted IPMC actuator depends on the applied voltage, palladium-electrode thickness, and actuator length. The contribution of the hydrogen assistance decreases with the applied voltage, while that of the hydrated cation movement increases. In addition, the specimen with a shorter length exhibits a larger hydrogen-induced moment ratio. These results suggest that the hydrogen assistance to the bending deformation is more effective in IPMC actuators with a shorter and thinner palladium electrode. [ABSTRACT FROM AUTHOR]

There are five closed types of piezo actuators (closed type of PA, closed PA) as a cooling fan relative to those different PAJs of the previous work (open type of PAJ, open PAJ) for analysis in the present study. Closed PA was composed of circular piezoelectric ceramics (PCs) and acrylic (PMMA) plates and investigated on five different types at operating conditions. The results show that the noise of the closed PA is quieter than that of the open PAJ by about 10 dB. When the closed PA is deposed at a suitable distance of 10 to 20 mm from the heat source, averting sucking back the high-temperature fluids around that, the thermal convection coefficient is above 120% more than that of the conventional rotary fan. The cooling performances of these five closed PAs were evaluated by thermal analysis technique, and the convection thermal resistance of the best closed PA can be decreased by over 15%. In terms of energy consumption, a monolithic closed PA was less than 10% than that of a rotary fan. Among these five closed PAs, the best one has the essential qualities that the diameter of the piezoelectric sheet is 41 mm, the opening length is 4 mm, and the outer opening length is 10 mm. Moreover, the best operating conditions are a voltage frequency of 300 Hz and a release distance of 15 mm in the present study. [ABSTRACT FROM AUTHOR]

The present work aims to analyze an electromechanical actuation, composed of a system in which we have a linear electromechanical actuator, nut screw type, with balls, driven by an asynchronous electric motor with the rotor in short circuit and controlled by a frequency and voltage converter. This work is part of a large study that aims to try to optimize some operating parameters of a linear electromechanical actuator. First, some characteristics of electromechanical with ball nut type actuators will be mentioned, then a presentation of a frequency and voltage converter. Finally, some results of some measurements regarding the actuation of the linear electromechanical actuator with an asynchronous motor with the short-circuited rotor will be presented and concluded. [ABSTRACT FROM AUTHOR]

The subcutaneous implant, which can realize on-demand drug release, is used for the treatments of some chronic diseases such as chronic pain, diabetes, and osteoporosis. This paper proposes a new type of wireless actuator for potential use in active implantable drug delivery systems. The proposed structure suits both wireless power well, which requires far-field flux traveling and receiving, and actuator design, which should take advantage of strong local magnetic fields. The mover in the actuator generates mechanical movement when power is transferred wirelessly to the actuator, and the mover restores to its original position when the wireless power stops. The maximum oscillation amplitude of the mover can be achieved when the ON and OFF frequency of the wireless power transfer is equal to the mechanical resonant frequency of the mover. Experimental results on a prototype actuator with 20 mm in diameter and 10.3 mm in thickness are given for validating the proposed new idea. [ABSTRACT FROM AUTHOR]

The suspension system needs both an active mode and passive mode when the emergency rescue vehicle is running on a complex road. Therefore, an active–passive composite suspension actuator (APCSA) is designed in this paper. Firstly, combined with computational fluid dynamics theory and dynamic mesh technology, the complete fluid domain of the original passive suspension actuator (PSA) is simulated. Secondly, in accordance with the simulation results and in consideration of the working conditions of the active suspension of the emergency rescue vehicle, the APCSA is designed, and its flow field characteristics are studied. Finally, test results show that the maximum recovery damping force/compression damping force of the APCSA is 2428.98 N/−1470.29 N, which is 53.5%/50.4% lower than that of the original PSA. Hence, the dynamic response capability of the actuator is effectively improved, which lays a foundation for improving the ride comfort and handling stability of emergency rescue vehicles on complex roads. [ABSTRACT FROM AUTHOR]

Inspired by biological deformation in nature, numerous efforts have been made on the fabrication of biomimetic actuators, and the most facile way is to endow a bilayered structure with one active layer and the other inert layer. Unfortunately, such actuators can generally achieve single‐stimulus response and small deformation due to only one active layer. Here, a polyvinyl alcohol (PVA)/polystyrene (PS) bilayered actuator with alternating active layers for realizing dual‐responsiveness and large deformation is designed and assembled. Basically, upon stimulation by humidity, the hydrophilic PVA layer acts as an active layer due to its excellent water affinity, while the strong hydrophobic PS layer is an inert layer, and the unmatched swelling of the two layers results in bending deformation. While when exposed to an organic vapor environment, the roles of the two layers are interchanged and the PS layer is switched to be active, leading to fast organic vapor‐triggered deformation. The effects of relative humidity, types of organic vapor, sizes of the actuator, thickness ratios of the two layers, and cutting angles on shape deformation are systematically investigated. The underlying mechanisms of dual‐responsive shape deformation are further clarified. Potential applications of the bilayered actuator are finally demonstrated. [ABSTRACT FROM AUTHOR]

This paper describes fabrication of a laminated film vibrator that uses an ultra-thin micro-electric mechanical system (MEMS) and the effect of lamination on the actuator. The thickness of the ultra-thin MEMS actuator fabricated by ultra-thin MEMS technology was 7.26 µ m, making it especially flexible. The vibrator was actuated by applying voltage on a lead zirconate titanate (PZT) thin film. Then, we applied a lamination method to package the actuator. However, the lamination structure influenced the mechanical characteristics of the vibrator. Therefore, we evaluated the effect of the lamination structure on the static and dynamic characteristics of the laminated film vibrator. Four types of laminated film vibrators with different layer structures were prepared, and their displacements and velocity were measured when DC and AC voltages were applied. The maximum displacement of the cantilevers constructed from the laminated film vibrator (PZT: 11 mm × 11 mm) was 113.3 µ m at 40 V DC. This result is in good agreement with the calculated result. Furthermore, the dynamic characteristics from both the experimental and simulated results confirmed that the resonant frequency of the laminated film vibrator depends on the film structure. This means the dynamic characteristics can be adjusted to suit the application. Applications of this laminated film actuator include use as a flexible hybrid electronics haptic device for monitoring vital signs. [ABSTRACT FROM AUTHOR]

Camera attitude control systems for robots require a compact structure and high responsiveness. However, due to the combination structure of several actuators, the camera attitude control system is large. To address this issue, this study proposes a three-degree-of-freedom (3DOF) voice coil actuator. A single actuator is used to generate 3DOF motion, which is driven by a four-phase current. This study also describes the basic structure and operating principle of the actuator and clarifies the torque characteristics using a three-dimensional (3D) finite element method (FEM). Furthermore, the dynamic modeling and control methods are presented. The FEM and dynamic simulation results reveal that the proposed actuator can be arbitrarily driven in 3DOF. [ABSTRACT FROM AUTHOR]

Carbon-fiber-reinforced plastic (CFRP) composites are intensively used in aircraft and aerospace industry thanks to their superior properties. Comparing to the conventional drilling (CD), vibration-assisted drilling (VAD) is a novel machining technique suitable for drilling CFRP. Still, multi-mode excitations with elliptical locus and low vibration performance limit the applications of current VAD schemes for CFRP. To overcome these limitations and improve the overall performance, an innovative longitudinal-torsional complex-mode ultrasonic vibration-assisted actuator with single excitation and an elliptical locus is presented employing a piezoelectric transducer and a stepped horn with spiral grooves. The proposed actuator is specially designed to deliver elliptical vibration and assure high vibration performance of a tool tip. Analysis of the actuation mechanism for the longitudinal-torsional composite vibration mode is discussed, and its simplified model is developed. A detailed design process of this actuator is given. Its vibration characteristics are verified with both finite-element simulation and experimental modal analysis using a swept sine test. It is demonstrated the developed prototype achieved longitudinal-torsional elliptical vibration. To validate the machining performance of the actuator, two groups of drilling experiments were performed. These indicate that the proposed actuator is capable of drilling CFRP with improved machining performance. [ABSTRACT FROM AUTHOR]

This article includes an overview of the materials and a thorough analysis of the methods that are used to produce dielectric electroactive actuator membranes. The paper also presents extensive results from our experimental studies on two types of addition silicone (Silicone Mold Start 15 and Dragon Skin 10M) that are used to manufacture actuators with different active membranes of thicknesses (165 μm and 300 μm, respectively). This study explored in depth the hardware architectures and methodologies for manufacturing the selected actuators. The displacements of the actuators were compared to their responses to two types of voltage excitation: a step response and a sinusoidal signal with an increasing frequency over time. This paper graphically presents the results that we obtained for all devices, with a particular emphasis on the resonance frequencies. When comparing membranes that had the same thickness (165 μm), it was found that the mean amplitude was higher for silicone membranes with lower values for the Young's modulus (DS = 0.57 m m and MS = 0.73 m m ). All experiments were repeated for two series of measurements and the results that were obtained in this study demonstrated the successful implementation of the actuator concepts that were made from the new types of silicone, which have not yet been used for production. [ABSTRACT FROM AUTHOR]

With the rapid development of DC systems and the increasing demand for DC circuit breakers, electromagnetic repulsive drive-based Thomson coil actuators (TCAs) are widely investigated to provide high-speed actuating required for ultra-fast mechanical switches, especially used in hybrid DC circuit breakers. The actuating mechanism is required to be fast, reliable, and economic. This also creates the need to perform fast highly accurate modeling, simulation, and optimization to investigate the operating mechanism performance. In this study, the fast-operating mechanism-based Thomson coil repulsive drive actuator modeling is investigated. Two simulation methods, equivalent-circuit method (ECM), and finite element method (FEM) are performed for analyzing the TCA performance. In the ECM simulation, Newton's equation of motion is solved together with the circuit equations of the coils. On the other hand, the electrical, magnetic, and mechanical coupling is solved by FEM simulation. A sliding mesh technique is introduced to reduce the computational cost. The two developed solutions were then compared with the experiment for model verification. Results showed that the presented mesh technique was able to significantly reduce the simulation time, and results were in good agreement with the experiment compared to ECM. [ABSTRACT FROM AUTHOR]

This paper proposes an adaptive barrier fast terminal sliding mode control (ABFTSMC) approach for quadrotor unmanned aerial vehicles (UAV). Its main objectives are to mitigate the external disturbances, parametric uncertainties, and actuator faults. An adaptive barrier function is considered in the design to ensure the finite-time convergence of the output variables to a predefined locality of zero, independent of the disturbance bounds. A fast terminal sliding mode control (FTSMC) approach is designed to speed up the convergence rate in both reaching and sliding phases. The design considers hyperbolic tangent functions in the adaptive control law to drastically reduce the chattering effect, typically associated with the standard SMC. The performance of the proposed approach was assessed using a quadrotor UAV subject to external disturbances and sudden actuator faults. The obtained results show that the trajectory and the sliding surface converge to the origin in a finite time, without being affected by the high disturbance and actuator faults. In this method, due to the substitution of the discontinuous function by the hyperbolic tangent function, the chattering effect has also been highly reduced. [ABSTRACT FROM AUTHOR]

This paper aims to present an effective fault diagnosis method-based detection for sensors, actuators, and system faults in a wind turbine machine. The proposed detection method is based on physical and analytical redundancy of sensors and actuators to generate the appropriate residuals between all measured variables. In this work, a crisp logic technique is used as classifier to investigate the main parts of the process including actuator and sensor faults. Using this logical procedure, we can detect different faults in blade pitch positions, drive train, and generator with converter for a wind turbine system. The obtained simulation results show the ability of this diagnosis method to identify faults effectively in the principal sub-systems of the studied wind turbine. [ABSTRACT FROM AUTHOR]

Actuators using Shape Memory Alloy (SMA) springs could operate in different mechanical systems requiring geometric flexibility and high performance. The aim of the present study is to highlight the potential of these actuators, using their dimensional variations resulting from the phase transformations of NiTi springs (SMA) to make the movements of the system's mobile components reversible. This reversibility is due to thermal-induced martensitic transformation of NiTi springs. The transformation promotes the extended and retracted of the springs as the phase changing (martensite–austenite) creates movement in part of the system. Therefore, the phase transition temperatures of NiTi, evaluated by differential scanning calorimetry (DSC), are required to control the dimensional variation of the spring. The influence of the number of springs in the system, as well as how impacts on the reaction time were evaluated. The different numbers of springs (two, four, and six) and the interspaces between them made it possible to control the time and the final angle attained in the mobile part of the system. Mechanical resistance, maximum angle, and the system's reaction time using different NiTi springs highlight the role of the actuators. Fused Deposition Modelling (FDM)/Material Extrusion (MEX) or Selective Laser Sintering (SLS) was selected for shaping the composite matrix system. A new prototype was designed and developed to conduct tests that established the relationship between the recoverable deformation of the matrix suitable for the application as well as the number and distribution of the actuators. [ABSTRACT FROM AUTHOR]

[Display omitted] • A strain measuring devices with a flex sensor for twisted actuators is proposed. • The device can measure the strain of the twisted actuator in the range of 9–36 %. • The displacement error is 0.5–0.8 mm compared with a laser sensor. • Multiple devices are introduced into a dexterous hand and closed-loop controller. • The trajectory of the robot is improved by the controller and introduced devices. The displacement of twisted and coiled polymer (TCP) actuators, a key physical characteristic, can be measured using a lightweight method, thereby improving the TCP responses and applications in the robot control. This work presents a strain measurement device based on the flex sensor and the hinge links applied in the displacement measuring of the TCP. The bent angle from the sensor affixed to the hinge is converted to the displacement value of the TCP based on the angle-strain model. Compared to the laser sensor, the calculated displacement of the device shows a good tracking effect within the 95 % confidence interval. In the dexterous hand prototype, finger trajectory and joint angles are smoother under a PID controller compared to a non-PID controller, demonstrating the effectiveness of feedback control involving displacement and tension. Finally, the device can cover an extensive range of TCP strains and be applied in more TCP-driven bionic robots. [ABSTRACT FROM AUTHOR]

[Display omitted] • A single family of star-shaped poly(ethylene glycol)-poly(lactide) photopolymers is proposed to yield biocompatible degradable hydration-based actuators. • Dual-materials microstructures are designed and easily printed from two photopolymers resins by stereolitographic digital-light processing. • Modelled actuation is experimentally validated confirming the concept of actuators designed from degradable photopolymers of same nature but distinct swellings. • The similar nature of the two photopolymers ensures a cohesive interface for a rapid actuation in less than a minute. Actuators are largely used in biomedical applications in the presence of sensitive live cells or biomolecules, which makes actuators triggered by water uptake highly appealing. Dual-material printing and hydration driven expansion is a method of choice to produce such actuators, but mostly rely of non-degradable polymers or on the combination of polymers of different nature that may lead to interface incompatibilities. To overcome this challenge, we report here on two photocrosslinkable resins based on a single family of degradable hydrophilic or hydrophobic star-shaped poly(ethylene glycol)-poly(lactide) copolymers. The two materials are first printed individually and characterized to ensure that their properties enable the printing of dual material objects by stereolithographic digital-light processing. Dual-materials actuators are then printed by sequential switching of the hydrophobic and hydrophilic resin baths. Objects of simple and complex shapes are easily obtained and exhibit rapid actuation (<60 s) upon hydration. The swelling-induced shape changes are accurately reproduced by numerical modeling of the printed geometries using the obtained material swelling properties. This set of results offers new perspectives to develop 4D-printed temporary medical devices. [ABSTRACT FROM AUTHOR]

Permanent Magnet (PM) Brushless Direct Current (BLDC) actuators/motors have many advantages over conventional machines, including high efficiency, easy controllability over a wide range of operating speeds, etc. There are many prototypes for such motors; some of them have a very complicated construction, and this ensures their high efficiency. However, in the case of household appliances, the most important thing is simplicity, and, thus, the lowest price of the design and production. This article presents a comparison of computer models of different design solutions for a small PM BLDC motor that uses a rotor in the form of a single ferrite magnet. The analyses were performed by using the finite element method. This paper presents unique self-defined parts of basic PM BLDC actuators. With their help, various design solutions were compared with the PM BLDC motor used in household appliances. The authors proved that the reference device is the lightest one and has a lower cogging torque compared to other actuators, but also has a slightly lower driving torque. [ABSTRACT FROM AUTHOR]

This paper presents the results of experimental and numerical investigations on synthetic jet actuators with various arrangements. First, an actuator with one membrane in the cavity is a standard, reference arrangement; and second, one novel modified arrangement has two membranes in the cavity. Authors use constant temperature-anemometry measurements to identify the characteristic frequencies in which the output jet velocity reaches a maximal value, namely, the resonant frequency of the actuator (Helmholtz frequency) and of the membrane (structural resonance). A numerical model of a synthetic jet actuator has been validated using experimental data for the case with one membrane in a cavity. The simulation results confirm the existence of a toroidal vortex at the actuator exit for the frequencies determined in the experiment. Numerical results of a modified actuator with two membranes in the cavity give promising results in the context of separation control by synthetic jet devices, i.e., increase of output velocity and vorticity from the same occupied space is obtained. Numerical simulations show that in the modified actuator with two membranes in the cavity, the jet output velocity and vorticity of a created toroidal vortex at the actuator outlet can be increased by 80%, compared to the case with one membrane. The new geometry of a synthetic jet actuator with perpendicular membranes is to be implemented into the wind tunnel measurements to prove the use of a modified synthetic jet actuator as a device applicable for active flow control. [ABSTRACT FROM AUTHOR]

Various mechanisms of plant organ movements have been reported, including the close association of two layers with expressed differences in hygroscopic properties. Following this principle, actuator beams composed of thin veneers out of normal and compression wood cut from Scots pine (Pinus sylvestris L.) were prepared by using two types of adhesives. The mismatch of the swelling properties of the two layers in tight combination resulted in an expressed bending deflection in response to set humidity changes. The resulting curvatures were measured and analyzed by the Timoshenko bi-metal-model, as well as with an enhanced three-layer model, with the latter also considering the mechanical influence of the glueline on the actuator bending. The thermally induced strain in the original model was replaced by another strain due to moisture changes. The strain was modelled as a function of wood density, along with changes in wood moisture. Experiments with free movement of the bilayer to measure curvature, and with constraints to determine forces, were performed as well. Deformation and magnitude of actuators movements were in close agreement with the enhanced bilayer-model for the phenol-resorcinol-formaldehyde adhesive, which deviated substantially from the casein adhesive glued actuators. The obtained results are seen as critical for wood-based actuator systems that are potentially used in buildings or other applications. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive sliding mode controller (ASMC) is proposed for an electromechanical clutch position control system to apply in the automated manual transmission. Transmission systems undergo changes in parameters with respect to the wide range of driving condition, such as changing in friction coefficient of clutch disc and stiffness of diaphragm spring, hence, an adaptive robust control method is required to guarantee system stability and overcome the uncertainties and disturbances. As the majority of transmission dynamics variables cannot be measured in a cost-efficient way, a non-linear estimator based on unscented Kalman filter (UKF) is designed to estimate the state valuables of the system. Also, a non-linear dynamic model of the electromechanical actuator is presented for the automated clutch system. The model is validated with experimental test results. Numerical simulation of a reference input for clutch bearing displacement is performed in computer simulation to evaluate the performance of controller and estimator. The results demonstrate the high effectiveness of the proposed controller against the conventional sliding mode controller to track precisely the desired trajectories. [ABSTRACT FROM AUTHOR]

Light electric vehicles are alternative solutions to passenger cars in terms their lower costs and space saving in city traffic. Narrow tilting vehicles (NTV), known also as three–wheeled vehicles, can be equipped with an active tilting stability controller that tilts the vehicle automatically during cornering to enable lateral stability. There are mainly direct tilt control (DTC), steering tilt control (STC), and combined DTC–STC methods described in the literature. The DTC method is typically applied up to 10 km/h vehicle speeds. Considering city traffic and frequent start–stop cycles, the DTC method needs to be improved in terms of lower actuator torque and energy consumption. DTC can be designed by using either hydraulic or servo motor actuators. In state of the art, the servo motor actuator has not been studied in detail considering its integration and application aspects. Mostly, the actuator has been considered as a black box model. Proposed control method in this study enables improvements in the direct tilt control system (DTC) in terms of reducing the actuator peak torque and enables the application of DTC at higher vehicle speeds. Regarding the modeling of the electric actuator, a permanent magnet synchronous motor and field-oriented control model are also included in the simulation model. Modelling of the electric actuator enables accurate representation of actuator dynamics. In this way, battery Ah capacity can be sized and energy consumption of the electric actuator can be calculated for a given drive cycle. To this end, objective of this study is to design a direct tilt control method including the electrical drives and motion control concepts. In this way, an application methodology of the servo motor actuator is developed and implemented on a narrow tilting three-wheeled electric vehicle. Interactions between tilt control system and the servo motor actuator system are described from practical aspects. [ABSTRACT FROM AUTHOR]

Summary: Servo‐hydraulic actuators are typically employed in real‐time hybrid simulation (RTHS) to impose dynamic loads on a specimen. The success and reliability of an RTHS depend on the accurate tracking of the command displacements by the actuators. This paper introduces a new adaptive compensation approach, adaptive discrete feedforward (ADF) controller, based on the principles of model‐based feedforward and feedback (MFF) controller. While the MFF controller relies on an accurate model of the controlled system obtained through system identification, the ADF controller updates its parameters to adapt to the changing dynamics of the controlled system during the test. This paper presents an experimental parametric investigation that determines the parameters required for implementing the ADF controller, such as the buffer size and the controller updating frequency. The performance of the ADF controller was compared with two other compensation methods: MFF controller and adaptive time series compensator in a series of predefined displacement tracking tests and RTHSs considering both linear and nonlinear specimens. The results are discussed in detail, where the ADF controller was shown to considerably improve the capability of the servo‐hydraulic actuator in tracking the command displacements. [ABSTRACT FROM AUTHOR]

This paper deals with the static, impact, and dynamic strength of reduction gears applied to a shift-by-wire (SBW) actuator system. A sintered material (FD-0405-60) was used for cost competitiveness and mass production. Therefore, strength verification is essential at the beginning of product development. A high-speed tensile test was conducted on the sintered material to understand the mechanical properties and stress-strain curve. After that, for detailed verification, the bending strength and contact strength of the gear were verified mathematically using modified Lewis equation and Hertz contact theory. Next, finite element method (FEM) was used to derive the static strain energy for the damage of each gear through ABAQUS. The impact strength was verified by comparing the static strain energy with the kinetic energy of each gear when the SBW actuator system was driven at the maximum speed. Flexible multibody dynamic analysis was then conducted to confirm the dynamic strength depending on the operating section (initial operation, during operation, collision stop) using ANSYS MOTION. In the future, we intend to implement frontloading by applying the process used in this study. [ABSTRACT FROM AUTHOR]