Deflection Displacement Research Articles

Mechanochemical characteristics and influence mechanisms of a biomass hydrogel artificial muscle based on different parameters of the sodium alginate adjustment

Biomass hydrogel artificial muscle (BHAM) is a kind of ionic electroactive polymers, such as ionic polymer gels of good biocompatibility and stimulus responsiveness under electric field, which is largely used in the fields of soft robots and electric actuators. In this paper, based on the freeze-drying process, effect and influence mechanisms of sodium alginate (SA) parameters adjustment on the BHAM mechanochemical characteristics were researched extensively, which was verified by a set of perfect characteristic evaluation and experimental test methods, such as the porosity P (v%), water retention rate W r (w%), mechanochemical property testing and scanning electron microscope shots. The results showed that when the concentration of SA was 20 g l−1, the actuating film of BHAM had suitable thickness and stomata in macroscopic appearance, and its micro pore distribution and size were uniform with the thin pore wall, which resulted in the highest porosity (i.e. ion channel) of 73.5 v%, the largest water retention rate of 76.2 w% and the optimum tensile strength of 0.38 MPa. Furthermore, calcium chloride (CaCl2) was adopted as a cross-linking agent to react with the SA to form calcium alginate (CA) by different CaCl2 cross-linking ratios, that was to modify the three-dimensional microstructure of the BHAM to improve its mechanical properties with the best deflection displacement of 23.9 mm and bending strain of 3.45% under the ideal CaCl2 cross-linking ratio of 1%. Besides, the diffraction of x-rays analysis and thermal decomposition experiments of the BHAM were performed, which was demonstrated that the thermal stability of the CA-based BHAM was higher than that of the SA-based BHAM.

Design, modeling, and research on vertical performance of a drive system with in-wheel motor as dynamic vibration absorber

There are many advantages to an in-wheel motor drive (IWMD) vehicle. However, installing the motor in the wheel will increase the unsprung mass and deteriorate the vehicle ride comfort. In this paper, this conclusion is verified by a comparative simulation test of ride comfort. To solve the above problems, this paper puts forward a new in-wheel motor drive (NIWMD) model and comprehensively evaluates the vertical performance of the vehicle from two aspects: vehicle ride comfort and motor vibration. The vertical performance evaluation indexes include body acceleration, wheel dynamic load, suspension dynamic deflection, motor acceleration, and motor relative displacement. The vertical performance of the NIWMD model, CMD model, and IWMD model is compared. The results show that, especially in the high-frequency resonance region, the NIWMD model can effectively suppress the peak vibration response and improve the vehicle vertical performance. The influence of system parameters of the NIWMD model is studied, and the sensitivity of system parameters is calculated. The research results show the parameters that have a great influence on the vehicle vertical performance, which points out the direction for the optimization of the vertical performance of the NIWMD model.

The electrostatic levitation system for active suspension control of test sample in horizontal and vertical axes

An electrostatic levitation system (ESLS) with active control model is proposed to realize the noncontact suspension of test sample for analyzing material properties. The characteristics about the electric field force and the electric image force of ESLS are firstly analyzed, and then the dynamic functions of test sample in the ESLS are developed. Furthermore, the conditions of test sample’s stable suspensions in horizontal and vertical directions are proposed, it shows that the control voltage is regulated to guarantee suspension stability of test sample considering the gravity and the displacement deflection in vertical direction. The control models of test sample in the ESLS are established to realize the active suspension in vertical and horizontal directions. Finally, both simulation and experiment with different suspension conditions are conducted to test the suspension characteristics of test sample in ESLS, and results indicate that the ESLS could stably suspend the test sample through regulating control voltages of high voltage electrodes and the displacements of test sample. Therefore, the ESLS could be used as a noncontact holder of test sample in materials testing instruments.

Экспериментальное и аналитическое исследование геометрически-нелинейного изгиба консоли под действием распределенной нагрузки гравитационного типа

This paper describes an approximate analytical solution for the geometrically nonlinear bending of a thin elastic cantilever beam under a uniformly distributed gravity load. The solution is based on the linearized Euler-Bernoulli equation of mechanics of materials. Traditionally, such a linear approach is used for small (geometrically linear) deflections. The authors have modified the original equation with an arc-length preservation condition. The modified solution allows one to obtain bending shapes, deflection, and axial displacement in the range of loads corresponding to geometrically nonlinear bending of a beam (large deflections). An experimental study is conducted to verify the proposed solution. A thin steel band bent by gravity is used as a sample. Changes in the length of the bent sample part allow one to obtain various dimensionless load parameters. The deflections and axial displacements averaged on experimental statistics are determined. Bending shapes are obtained by the least square method of 5th order. Experimental and theoretical data are shown to be in good agreement. This fact confirms that the approximate analytical solution can be applied to solve large deflection problems in a wider range of loads than normally considered in the original linear theory.

An alN-based piezoelectric micromachined ultrasonic transducer with a double-beam suspended structure

ABSTRACT This paper presents an AlN-based piezoelectric micromachined ultrasonic transducer (PMUT) with a double-beam suspended structure. In order to obtain greater deflection displacement and output sound pressure compared to standard systems, a suspended structure is proposed, achieved by utilizing double-sided deep reactive ion etching of the silicon substrate. This structure is capable of greatly reducing the tensile stress caused by deflection on the membrane edge, thereby improving the piezoelectric micromachined ultrasound transducer performance. Simulations are performed using the finite element method and COMSOL software, with results demonstrating that the suspension structure exhibits a lower resonant frequency and a larger membrane deflection displacement than other methods, implying higher penetration and acoustic energy levels. Thus, the sound pressure is improved by changing the PMUT structure. Moreover, a PMUT with a double-beam is fabricated, and the impedance diagram is determined with an impedance analyzer. The resonant frequency of the transducer was 31.88 kHz, while the sound wave received by the standard lead zirconate titanate (PZT) ultrasonic transducer was converted to a voltage of 277.5 mV. In comparison, the proposed PMUT demonstrates an improved acoustic emission performance. In addition, the electromechanical coupling coefficient of the suspended PMUT is observed to be approximately 3.08%, which is significantly better than that of a fully clamped PMUT. This demonstrates the strong electromechanical conversion performance of the proposed PMUT. Results from the transmission and reception air experiments prove that the proposed double-beam PMUT can potentially be used for ranging and wireless energy transmission applications.

Effect of carboxymethyl cellulose on the output force and electrochemical performance of sodium alginate ion electric actuator

This paper studies the influence of the mass of carboxymethyl cellulose on the SCIA sample of the sodium alginate biogel ion electric actuator. An experimental platform is built to study its deflection displacement and output force characteristics. The internal structure of the ion electric actuator was observed by a scanning electron microscope. Further test SCIA samples with infrared and electrochemical workstation. Studies have shown that when the mass of CMC is 0.25 g, the comprehensive performance of the SCIA sample is the best, the output force performance is good, the ion channel is the largest, and the response speed is fast. The maximum output force is 2.675 mN, the maximum deflection displacement is 17.137 mm, the maximum response speed is 0.176 mm/s, and the maximum specific capacitance in electrochemical performance is 96.95 mF/g. However, with the increase of CMC and excessive cross-linking, the performance of SCIA samples decreased.

A highly flexible and stretchable ionic artificial muscle

It is well known that ionic electroactive polymer (iEAP)-like artificial muscles with a faster response, greater strength and better tensile strength are critical to improve the electromechanical properties and expand their applications in wearable devices, soft sensors and actuators. Recently, polyvinyl alcohol (PA) hydrogels have greatly attracted attention because of their good tensile properties and biocompatibility. Thus, an ionic electroactive polymer with outstanding flexibility and excellent stretchability was developed based on the plasticizing treatment method by polyvinyl alcohol cross-linked with acrylamide in this work (PA-iEAP). The results showed that the tensile properties and electromechanical properties of PA-iEAP were greatly improved. Additionally, the output force and the peak deflection displacement of PA-iEAP reached 1.6 and 2.73 times those without plasticizing treatment, respectively. A bionic grip fabricated by PA-iEAP imitating mimosa was demonstrated. This work illustrated a kind of green ionic electroactive polymer with a simple method, low cost and outstanding tensile potential, which is very promising for improving the electromechanical properties of artificial muscles in the biomedical field and bionic robotics.

Estimation of Post-Cracking Dissipation Capabilities of Fiber Reinforced Concretes in Three Point Bending Test Monitored with Application of Digital Image Correlation System.

Concretes with dispersed reinforcement are increasingly used in structural engineering. The basic source of knowledge on their application and design are the Model-Code 2010 guidelines. These guidelines, however, apply mainly to steel rebar reinforcement and are not fully sufficient in the analysis of the load-bearing capacity of elements made of concrete with dispersed reinforcement. Therefore, scientific research in this field is carried out continuously. The main goal of our work is to provide experimental data for the calibration of constitutive models of the cracking mechanics of concrete with reinforcement in the form of steel and polypropylene fibers. This article shows the possibility of using the digital image correlation system (DIC) to achieve this goal. The method of sample preparation and the method of conducting the tests were modeled on the recommendations contained in the PN-EN 14651: 2007 standard. The tests were carried out on prismatic elements with a notch loaded in a three-point bending setup. The results of standard strength tests are presented in the form of column graphs and tables. As an extension, the results of calculations of energy dissipated in fracture process are given. Moreover, the experimentally obtained graphs of the relationship between the force, displacement and crack opening were presented, which were supplemented with the images of crack development obtained with the use of DIC. The development of the crack net is characterized not only qualitatively but also quantitatively as a function of deflection or crack mouth opening displacement. Conclusions concerning the adopted research methodology and the tested materials are presented at the end of the article.

Flexural Tensile Strength of Concrete with Synthetic Fibers.

Fiber reinforcement is currently most often used in floors, railway sleepers, prefabricated structural elements such as slabs, beams and tanks, and in small architecture elements. Designing elements or structures made of fiber-reinforced concrete requires knowledge of its basic mechanical parameters. In the case of concretes with metallic fibers, the literature can find many tests and standard guidelines regarding compressive, flexural, tensile strength and fracture energy. The properties of concretes with non-metallic fibers are slightly less recognized, especially concretes with new types of polymer fibers. Additionally, the lack of standardized methods of testing concrete with polymer fibers make their application much more difficult. In the article, the possibility of using the EN 14651 standard to assess the flexural tensile strength of concrete with the addition of 2.0 and 3.0 kg/m3 of synthetic fibers with different geometry and form was presented. There was a 5.5–13.5% increase in the flexural tensile strength depending on the mixture type. Moreover, in the case of fiber-reinforced concretes, the ductility was enhanced and the samples were characterized by significant residual flexural tensile strengths. Additionally, from the workability tests it was concluded that after the incorporation of fibers, the consistency class decreased by one, two or three. Nevertheless, the compressive strengths of concrete with and without fibers were very similar to each other, and varied from 58.05 to 61.31 MPa. Moreover, it was concluded that results obtained from three-point bending tests significantly differed from empirical formulas for the calculation of the flexural tensile strength of fiber-reinforced concretes with dispersed steel fibers present in the literature. As a result, the new formula determined by the authors was proposed for concrete with polymer fibers with a nominal fiber content ≤1.0% and slenderness of up to 200. It must be mentioned that the formula gave a very good agreement with studies presented in different literature positions. In addition, an attempt was made to evaluate the strengths of tested mixes in accordance with the Model Code 2010. However, it occurred that the proposed fiber-reinforced concrete mixtures would not be able to replace traditional reinforcement in a form of steel bars. Furthermore, in uniaxial tensile tests, it was not possible to determine the σ–w graphs, and received results for maximum tensile strength did not show the clear influence of fibers incorporation on concrete. Then, the fracture energy enhancement (from about 16 to 22 times) and dependencies: crack mouth opening displacement–deflection; crack mouth opening displacement–crack tip opening displacement; and crack tip opening displacement–deflection were analyzed. Finally, the results from flexural tensile tests were compared with measurements of the surface displacement field obtained through the Digital Image Correlation technique. It was concluded that this technique can be successfully used to determine the crack mouth and crack tip opening displacements with very high accuracy.

ELASTIC BENDING OF A THREE-LAYER CIRCULAR PLATE WITH STEP-VARIABLE THICKNESS

The bending of a three-layer elastic circular plate with step-variable thickness is considered. To describe kinematics of asymmetrical in thickness core pack, the broken line hypotheses are accepted. In thin bearing layers, Kirchhoff’s hypotheses are valid. In a relatively thick filler incompressible in thickness, Timoshenko’s hypothesis on the straightness and incompressibility of the deformed normal is fulfilled. The formulation of the corresponding boundary value problem is presented. Equilibrium equations are obtained by the variational Lagrange method. The solution of the boundary value problem is reduced to finding three required functions in each section, deflection, shear and radial displacement of the median plane of the filler. An inhomogeneous system of ordinary linear differential equations is obtained for these functions. The boundary conditions correspond to rigid pinching of the plate contour. A parametric analysis of the obtained solution is carried out.

СРАВНЕНИЕ РЕШЕНИЙ ЗАДАЧ ИЗГИБА ТРЕХСЛОЙНЫХ ПЛАСТИН НА ОСНОВАНИЯХ ВИНКЛЕРА И ПАСТЕРНАКА

Solutions of problems on axisymmetric bending of an elastic three-layer circular plate on the Winkler and Pasternak foundations are given. The bearing layers are taken as isotropic, for which Kirchhoff’s hypotheses are fulfilled. In a sufficiently thick lightweight, incompressible in thickness aggregate, the Timoshenko model is valid. The cylindrical coordinate system, in which the statements and solutions of boundary value problems are carried out, is connected with the median plane of the filler. On the plate contour, it is assumed that there is a rigid diaphragm that prevents the relative shear of the layers. The system of differential equations of equilibrium is obtained by the variational method. Three types of boundary conditions are formulated. One- and two-parameter Winkler and Pasternak models are used to describe the reaction of an elastic foundation. The solution to the boundary value problem is reduced to finding three desired functions, plate deflection, shear, and radial displacement in the filler. The general analytical solution to the boundary value problem is written out in the case of the Pasternak model in Bessel functions. At the Winkler foundation, the known solution is given in Kelvin functions. A numerical comparison of the displacements and stresses obtained by both models with a uniformly distributed load and rigid sealing of the plate contour is carried out.

Повторное знакопеременное нагружение упругопластической трехслойной пластины в температурном поле

Axisymmetric deformation of a three-layer circular plate under repeated alternating loading from the plastic region by a local load is considered. To describe kinematics of asymmetrical on the thickness of the plate pack is adopted the hypothesis of a broken line. In a thin elastic-plastic load-bearing layers are used the hypothesis of Kirchhoff. A non-linearly elastic relatively thick filler is incompressible in thickness. It is taken to be a hypothesis of Tymoshenko regarding the straightness and the incompressibility of the deformed normals with linear approximation of the displacements through the thickness layer. The work of the filler in the tangential direction is taken into account. The physical relations of stress-strain relations correspond to the theory of small elastic-plastic deformations. The effect of heat flow is taken into account. The temperature field in the plate was calculated by the formula obtained by averaging the thermophysical parameters over the thickness of the package. The system of differential equations of equilibrium under loading of the plate from the natural state is obtained by the Lagrange variational method. Boundary conditions on the plate contour are formulated. The solution of the corresponding boundary value problem is reduced to finding the three desired functions: deflection, shear and radial displacement of the shear surface of the filler. A non-uniform system of ordinary nonlinear differential equations is written for these functions. Its analytical iterative solution is obtained in Bessel functions by the method of elastic solutions of Ilyushin. In case of repeated alternating loading of the plate, the solution of the boundary value problem is constructed using the theory of variable loading of Moskvitin. In this case, the hypothesis of similarity of plasticity functions at each loading step is used. Their analytical form is taken independent of the point of unloading. However, the material constants included in the approximation formulas will be different. The cyclic hardening of the material of the bearing layers is taken into account. The parametric analysis of the obtained solutions under different boundary conditions in the case of a local load distributed in a circle is carried out. The influence of temperature and nonlinearity of layer materials on the displacements in the plate is numerically investigated.

Analysis of a curved Timoshenko nano-beam with flexoelectricity

A Timoshenko beam model is applied for the analysis of the flexoelectric effect for a curved nano-beam. This theory transforms the beam to a 1-d problem along the beam axis. The electric intensity vector for the open-circuit condition can be expressed by mechanical quantities, namely strains and strain gradients. The variational principle is applied to derive the system of ordinary differential equations (ODEs) for the beam deflection, cross-section rotation, and in-plane displacement. A numerical solution based on the Taylor series expansion with Cartesian coordinate along the beam is proposed for the system of ODEs. A convergence analysis with respect to the number of terms in the Taylor series expansion is performed. Numerical results for the beam deflection, rotation, in-plane displacement, and induced electric intensity vector are presented for various flexoelectric coefficients and the beam curvature.

Venolymphatic malformations: prenatal diagnosis using magnetic resonance imaging, perinatal outcomes and long-term follow-up.

Venolymphatic malformations are benign. Fetal MRI can more precisely demonstrate an infiltrative pattern of malformations than US. To evaluate perinatal outcomes and long-term follow-up of fetal venolymphatic malformations treated in different medical facilities using fetal MRI. This retrospective cohort study evaluated 20 pregnant women between 22weeks and 37weeks of gestation who were referred from different institutions. They presented with fetuses with various diagnoses of cystic masses on routine US. The cases were studied using MRI. We analyzed prenatal data, perinatal outcomes and long-term follow-up. We reviewed the MRI scans of 20 patients with venolymphatic malformation. Referral diagnosis was changed in 40% (8/20) of cases, with postnatal concordance of 100% (20/20). Moreover, 65% (13/20) presented with venolymphatic malformation in more than one body segment. The neck was affected in 70% (14/20) of fetuses, while the head and thorax were affected in 30% (6/20) and 45% (9/20), respectively. There were intrathoracic lesions in 35% (7/20), lesions in the abdomen in 30% (6/20), and lesions in the perineum and extremities in 10% (2/20) each. Tracheal displacement, neck deflection and anatomical displacement caused by tumoral compression were present in 15% (3/20) of cases. Moreover, 25% (5/20) of newborns required neonatal intensive care unit admission, and all presented with cervical or thoracic venolymphatic malformation. Furthermore, 50% (10/20) of cases presented with complete resolution after medical therapy. The intrathoracic and cervical residuals (35%, 7/20) were monitored and treated. MRI showed good correlation with postnatal examination of venolymphatic malformation, was useful in the differential diagnosis of fetal cysts on US, and presented a significant postnatal correlation with thoracic infiltration. The outcomes of prenatally diagnosed venolymphatic malformations are good despite the varying protocols among medical facilities.

Study on the mechanisms of curved water jet fiber-guided laser technology

The emergence of a novel technology, curved water jet fiber (CWJF)-guided laser, will broaden the application of water jet-guided laser in surface high precision and no damage micromachining, such as micro-texture treatment, drilling and grooving, etc., of inclined and curved workpiece, in particular, like some large and heavy parts that are difficult to move and rotate. In addition, the novel scheme of high precision, low damage, and circular section processing with the transmission laser and cooling effect of CWJF will be investigated. In this study, the parametric control of water jet deflection is explored using the model of the deflection trajectory of water jet discretized into continuously released water droplets under a nonuniform electric field, in which results show that large deflection angle and displacement can be obtained with high voltage, small distance, and low velocity. Optical transmission system models of CWJF-guided laser under related parametric groups are established through 3D physical reconstruction models of CWJF by using the deflection trajectory. The theoretical calculation of meeting total reflection conditions of incident rays and visualization analyses of CWJF formed-guided laser indicate laser beam can be transmitted effectively. The laser beam is still confined to CWJF and transmitted forward. The methods and results presented in this study will provide the theoretical support and reference for the control of CWJF formation and research of characteristics about CWJF-guided laser during this novel technology development journey.

Experimental and Numerical Investigation on Bearing Capacity of Circumferential Joint of New Spatial Steel Tubular Grid Arch in Mined Tunnel

Under the circumstance of soft fractured surrounding rock with high geo-stress, the support technology of tunnel has become a major challenge. Traditional I-shaped steel and bar lattice girder, which cross-sections are often designed to be left-right symmetrical, may have insufficient strength and stiffness. Based on the concept of symmetry, a new support technology of spatial steel tubular grid (SSTG) arch is designed with high strength and large stiffness. In order to clarify the mechanical properties and failure mechanism of SSTG arch used as primary support, through laboratory and numerical experiments, this paper carries out the bending tests for the circumferential joint of SSTG arch components combined with the excavation tunnel project of Panyu Square Station in Guangzhou, and the analyses of the ultimate bearing capacity, deflection displacement, failure modes, and stress–strain evolution laws of joint components are conducted in detail. The results show that during the whole process of loading, the arch components have experienced elastic growth stage, plastic development stage, and final failure stage. The average ultimate bending capacity of SSTG arches is 340.5 kN·m, and the joint opening is 13.9 mm. The joint form of high-strength bolt + rigid flange plate proposed in the paper has reasonable stress state and high safety redundancy, which can bear the load of surrounding rock effectively, and ensure the safety in tunnel construction. The research results could provide a theoretical basis for the design and application of SSTG arch support in related projects.

Investigation of posterior teeth displacement under normal bite force by an intraoral scanner

Objective: To quantitatively evaluate the change of the long axis angle and the relative displacement of the crown feature points of the posterior teeth under normal bite force utilizing an intraoral scanner, and to provide clinical reference. Methods: From May to December 2019, fifteen graduate volunteers (5 males and 10 females, aged from 22 to 30, with an average age of 25.7 years) from Peking University School and Hospital of Stomatology were recruited to participate in the study. The surface data (U1, L1) of the maxillary and mandibular posterior teeth were scanned by an intraoral scanner i500, and saved as original data. The volunteers were guided to bite in the intercuspal position with normal bite force. The buccal bite data of the posterior teeth were scanned as the basis for registration. The digital casts were imported into Geomagic studio 2013 software and the boundary lines along the gingival margin and mesial and distal contact area of posterior teeth of data (U1, L1) were determined. Long axis of the crown, crown centroid and mesial functional cusp vertex were establishd. The data (U1, L1) were segmented into single tooth. Single tooth was aligned to buccal bite data separately using best-fit alignment command based on the buccal common area of the crown and new casts data (U2, L2) were obtained as the data under bite force. The long axis angle and centroid distance between adjacent teeth (second premolar and first molar, second molar and first molar) were measured and the deviation between data obtained at mouth-open state and that at biting state was calculated. Negative value meant centroid distance became shorter under bite force. The first molar was set as the common area and registrate the U1, L1 to U2, L2. The angle of long axes, and displacement of centroid and of functional cusp vertex between second premolar of two casts were calculated, as well as between second molar of two casts. Wilcoxon signed rank test was used to analyze the differences of teeth displacement between second premolar and second molar, and between maxillary and mandibular jaws with SPSS 26.0 statistical software. Results: The result of second premolar and second molar in the same jaw had no statistical difference (P>0.05). The centroid distance deviation of mandibular second premolar-first molar [-0.022(0.046) mm] was larger than that of maxilla [-0.006 (0.040) mm] (P<0.05). The long axis angle of second premolar itself [0.913°(0.647°)] and centroid distance of second molar itself [0.102 (0.106) mm] on the mandibular jaw were different from that on the maxillary jaw, which were 0.590°(0.550°) and 0.074(0.060) mm respectively (P<0.05). Conclusions: Under bite force, displacement of the second premolar and second molar was present, including the displacement of centroids and deflection of long axes. The mandibular posterior teeth have larger displacement than the maxillary teeth.

Experimental Study on Concrete-Filled Double Skin Circular Steel Tubular Beams under Bending Load

This paper examines the structural and mechanical behavior characteristics of the concrete-filled double circular steel tube (CFDT) fabricated with the installation of shape memory alloys (SMAs) and reinforcement bars in the inner and outer steel tubes, the inner-outer diameter ratio (Di/Do), and the concrete strength as the main variables. Towards this end, the displacement ductility, crack patterns, load-central deflection relationship, displacement ductility, and flexural shear strength were compared and analyzed. The results verified that a change in the Di/Do has significant effects on the crack pattern, maximum load, and ductility. The specimens with SMAs installed between the inner and outer steel tubes generally showed good results.

FULL CAR ACTIVE DAMPING SYSTEM FOR VIBRATION CONTROL

Full car passive and active damping system mathematical model was developed. Computer simulation using MATLAB was performed and analyzed. Two different road profile were used to check the performance of the passive and active damping using Linear Quadratic Regulator controller (LQR)Road profile 1 has three bumps with amplitude of 0.05m, 0.025 m and 0.05 m. Road profile 2 has a bump with amplitude of 0.05 m and a hole of -0.025 m. For all the road profiles, there were 100% amplitude reduction in Wheel displacement, Wheel deflection, Suspension travel and body displacement, and 97.5% amplitude reduction in body acceleration for active damping with LQR controller as compared to the road profile and 54.0% amplitude reduction in body acceleration as compared to the passive damping system. For the two road profiles, the settling time for all the observed parameters was less than two (2) seconds. The present work gave faster settling time for mass displacement, body acceleration and wheel displacement.

A machine learning method for inclinometer lateral deflection calculation based on distributed strain sensing technology

Due to its unique advantages, the distributed fiber optical sensing (DFOS) technology has been used to study the performance of inclinometer so as to monitor landslide deformation. Strain distribution of inclinometer can be obtained by distributed strain sensing (DSS) cables, and the strain-deflection relationship can be established by using the widely accepted methods (e.g., the quadratic integral method and classical conjugate beam method). However, the application of quadratic integral method and classical conjugate beam method are based on many assumptions, and there will be remarkable deviation between calculated deflection and actual displacement with the increase of integral length. Given this, a new deflection calculation method based on machine learning is proposed. Through learning on the monitoring data, an implicit function model between depth, strain, and measured displacement is established by using the BP (back propagation) neural network algorithm. The efficiency of the proposed model has been verified against measured displacement, which demonstrates the capability of this method for landslide deformation prediction. Compared with the traditional integral method, the lateral deflection curve of inclinometer calculated by the proposed method is closer to the actual measured displacement both in trend and values. The proposed model shows great potential in the application of deflection calculation in engineering.