Central Angle Research Articles

Many-body Aharonov-Bohm caging in a lattice of rings

We study a system of a few ultracold bosons loaded into the states with orbital angular momentum $l=1$ of a one-dimensional staggered lattice of rings. Local eigenstates with winding numbers $+l$ and $-l$ form a Creutz ladder with a real dimension and a synthetic one. States with opposite winding numbers in adjacent rings are coupled through complex tunnelings, which can be tuned by modifying the central angle $\phi$ of the lattice. We analyze both the single-particle case and the few boson bound-state subspaces for the regime of strong interactions using perturbation theory, showing how the geometry of the system can be engineered to produce an effective $\pi$-flux through the plaquettes. We find non-trivial topological band structures and many-body Aharonov-Bohm caging in the $N$-particle subspaces even in the presence of a dispersive single-particle spectrum. Additionally, we study the family of models where the angle $\phi$ is introduced at an arbitrary lattice periodicity $\Gamma$. For $\Gamma>2$, the $\pi$-flux becomes non-uniform, which enlarges the spatial extent of the Aharonov-Bohm caging as the number of flat bands in the spectrum increases. All the analytical results are benchmarked through exact diagonalization.

Optimization of the Injectors Position for an Electric Arc Furnace by using CFD Simulation

In this study, complex processes in a typical Electric Arc Furnace (EAF) such as combustion, radiation, heat, and mass transfer were solved and the optimum injector location was found using computational fluid dynamics (CFD). The main aim of the injection optimization was to improve the thermal performance and the metallurgical process by changing the injection angle, the central angle of the injector (CAI), and injector length. Fifteen parametric cases were predicted and analyzed for optimization study. To decrease each simulation solution time of each cases, a polyhedral mesh structure was used instead of tetrahedral mesh for the EAF geometry. Thus, the total element number of the model was decreased by 1/5 while providing faster and unchanging results compared to the case with a tetrahedral mesh structure. The response surface optimization method was used for the optimization study. As a result, the optimum injector positioning was obtained as injection angle: -45°, injector length 614 mm, and CAI: 60°.

Relationship between the gross motor function classification system and hip and lumbar spine development in children with spastic cerebral palsy

To investigate the relationship among the gross motor function classification system (GMFCS)and the development of hip joint and lumbar spine in children with spastic cerebral palsy. The clinical data of 125 children with spastic cerebral palsy admitted from January 2018 to July 2021 were retrospectively analyzed. There were 85 males and 40 females, aged from 4 to 12 years old with an average of (8.4±2.9) years. According to GMFCS, the patients were divided into gradeⅠ, Ⅱ, Ⅲ and Ⅳ groups. There were 27 cases in gradeⅠgroup, 40 cases in gradeⅡgroup, 35 cases in grade Ⅲ group and 23 cases in grade Ⅳ group. The migration percentage(MP), central edge angle(CE), neck-shaft angle(NSA), acetabular index(AI) were measured by the radiograph of pelvis, abnormal parameters were selected to evaluate the relationship between different GMFCS grades and hip joint development. Lumbar sagittal Cobb angle, lumbar sacral angle, lumbar lordosis index and apical distance were measured by lateral lumbar radiographs to evaluate the relationship between different GMFCS grades and lumbar spine development. ①Among the 125 spastic cerebral palsy children, there were 119 cases of pelvic radiographs that met the measurement standards. In the four groups with gradeⅠ, Ⅱ, Ⅲ, Ⅳ, MP was (22.72±3.88), (26.53±4.36), (33.84±4.99), and (49.54±7.87)%, CE was(30.10±6.99) °, ( 22.92±4.19) °, ( 17.91±5.50) °, and (-0.70±17.33)°, AI was (16.41±2.77) °, (20.46±4.63) °, (23.76±5.10) °, and ( 29.15±7.35)°, respectively, there were significant differences between the two comparisons (P<0.05). And the higher GMFCS grade, the greater MP and AI, and the smaller CE.The NSA was(142.74±10.03) °, (148.66±9.09) °, (151.66±10.52) °, and (153.70±8.05)° in four groups with gradeⅠ, Ⅱ, Ⅲ, Ⅳ, respectively. The differences between the two comparisons of the GMFCS gradeⅠgroup and the other three groups were statistically significant (P<0.05). NSA of GMFCSⅠgroup was significantly lower than that of the others, there was no significant difference among other groups(P>0.05). ② Among the 125 spastic cerebral palsy children, there were 88 cases of lumbar spine radiographs that met the measurement standards. ③The lumbar sagittal Cobb angle was(32.62±11.10) °, (29.86±9.90) °, (31.70±11.84) °, and (39.69±6.80)° in the four groups with gradeⅠ, Ⅱ, Ⅲ, Ⅳ, respectively;GMFSS of grade Ⅳ group was significantly higher than that of other three groups, there was significant difference between the two comparisons (P<0.05);there were no significant differences between other groups (P>0.05). In the four groups with gradeⅠ, Ⅱ, Ⅲ, Ⅳ, the lumbosacral angle was (31.02±9.91) °, ( 26.57±9.41) °, (28.08±8.56) °, and ( 27.31±11.50)°, the lumbar lordosis index was (4.14±12.89), (8.83±13.53), (13.00±11.78), and (10.76±9.97) mm, the arch apex distance was (9.50±6.80), (6.68±3.20), (7.16±4.94), and (6.62±4.13) mm, respectively, there were no significant differences between the two comparisons(P>0.05). ①In children with GMFCS gradeⅠ-Ⅳ, the higher the GMFCS grade, the worse the hip develops. ② Children with GMFCS grade Ⅲ-Ⅳ may be at greater risk for lumbar kyphosis.

Motion Error Estimation and Compensation of Airborne Array Flexible SAR Based on Multi-Channel Interferometric Phase

Airborne array synthetic aperture radar (SAR) has made a significant breakthrough in the three-dimensional resolution of traditional SAR. In the airborne array SAR 3D imaging technology, the baseline length is the main factor restricting the resolution. Airborne array flexible SAR can increase the baseline length to improve the resolution and interference performance by mounting antennae on the wing. The existing research lacks results obtained using flexible actual data processing and specific motion compensation methods. Thus, this paper proposes a motion error estimation and compensation method for an airborne array flexible SAR based on a multi-channel interferometric phase. Firstly, a flexible channel motion compensation model is established based on the multi-channel interference phase of airborne array flexible SAR. Then, based on the rigid multi-channel data, combined with the ground control points, the least square method, and the global optimal search algorithm, the accurate rigid baseline length and the central incidence angle are obtained. Finally, according to the multi-channel interference phase inversion of the flexible motion error and combined with the motion compensation model, the flexible data are compensated in the time domain. The actual results indicate that, compared with traditional motion compensation methods, our method can obtain accurate flexible compensation data. This study improves the interference performance of multi-channel data of airborne array flexible SAR and lays a solid foundation for the high-precision 3D reconstruction of airborne array flexible SAR.

Behavior of thread-fixed one-side bolts bolted T-stubs with arc-shaped flange to steel tube under tension

Tensile tests and Finite Element (FE) analysis were conducted on the Thread-fixed One-side Bolts (TOBs) bolted T-stub with arc-shaped flange to steel tube in this paper. Critical parameters were determined as the thickness of tube wall, the outer diameter of steel tube, the thickness of arc-shaped flange, and the center angle between bolts. Test results revealed that the connection would encounter three typical failure modes, which were: failure mode 1, thread shear failure with yielding of tube wall; failure mode 2, complete yielding failure of tube wall; failure mode 3, thread shear failure with yielding of T-stub arc-shaped flange. Developed FE models are verified and used to analyze the yield line pattern of tube wall, the hoop stress distribution of cross-section of tube wall, and the shear acting on bolt shank. Based on the experimental and numerical results, preliminary analytical models and design methods are proposed to estimate the tensile yield strength of specimens under different failure modes.

Percolation threshold and electrical conductivity of conductive polymer composites filled with curved fibers in two-dimensional space.

Quantifying the influence of fiber curvature on the percolation behavior of flexible conductive fiber and further on the electrical conductivity of conductive polymer composites (CPCs) is crucial for the design of CPCs. This study considers CPCs as a random packing of soft curved discorectangles (CDCRs) in a polymer matrix. The geometry of CDCR is developed, and an inter-CDCR contact detection algorithm is used to generate a random packing structure of CDCRs. The effects of aspect ratio α and bending central angles θ of CDCR on the percolation threshold ϕc of the overlapped CDCR system in a two-dimensional plane are then investigated using the finite-size scaling method. The result reveals that ϕc decreases monotonically as α grows and increases monotonically as θ rises. A shape-independent power law formula, denoted as ϕc = 2.2015 A-0.8172dex is developed to quantify the relationship between the Adex and ϕc. A comparison of our numerical simulations, published data, and predictions verifies the reliability and universality of the fitting model. Subsequently, a resistor network searching algorithm (RNSA) is proposed to construct the random resistor network model (RRNM). A power law model, denoted as is developed to evaluate the effects of the normalized reduced density (η - ηc)/ηc on the effective conductivity σeff of CPC. Comparing our predictions with data from the literature and our simulation verifies the reliability of our RNSA and the fitting model. This paper's methodology and findings may provide a theoretical hint for the CPC's design.

Research of the crop seed unloading process from the treatment chamber of a rotary seed treater

Purpose. Enhancing the productivity of the process of layer-by-layer application of protective agents on the seeds of agricultural crops through the justification of the shape of the unloading window of the seed treatment chamber of rotary batch treaters. Methods. The research uses an analytical and experimental methods using Microsoft Office software environments. Results. The analytical dependence of the ratio of the width of the live cross-section of the seed flow to the width of the unloading window on the central angle of the window girth and the experimental dependence of the seed unloading time from the processing chamber on the mass of its portion and the rotor rotation frequency were obtained. Conclusions. The ratio of the width of the live section of the flow of processed seeds to the width of the unloading window increases proportionally with the increase in the central angle of the window. The throughput of an unloading window with a larger window width is greater than the throughput of an unloading window with a smaller window width for the same area. The time of discharge of processed seeds depends on both the mass of its portion and the frequency of rotation of the rotor. At the same time, the seed unloading time from the processing chamber increases with the increase in the weight of its portion and at a rotor speed of 250 rpm is 4.3 s for a seed portion weight of 3.5 kg and 6.9 s for 14 kg portion weight. The time of seed discharge from the processing chamber decreases with an increase in the rotor rotation frequency, and for 10.5 kg seed portion weight, it is 5.4 s at a rotor rotation frequency of 150 rpm and 4 s at a rotor rotation frequency of 250 rpm. Keywords: seeds, treatment chamber, seed treater, layer treatment, protective preparations, unloading.

Estimation of hydrodynamic loads acting on downstream fastening plates of low-pressure tubular structures

In the article are presented the results of the state analysis of low-pointed tubular culverts widely used in land reclamation and fisheries construction, the lower pool of which is made in the form of an expanding socket with a central angle of 300 to 600 and checker-type energy absorbers. Field surveys have shown that only in the Moscow region such structures, built mainly in the 60-70s of the last century, makeup 76% of the total number of structures on water systems. The condition is from 70% to 85% of them, depending on the region unsatisfactory: the dampers are deformed and even shifted, the lining of the water break and the apron is destroyed, excessive erosion is observed in the discharge channel. The results of experimental studies of the averaged and pulsating pressure on the downstream attachment elements (the bottom of the water break in the flooded hydraulic jump zone and the initial sections of the apron), performed at Reynolds numbers (20...75) 103 on a model installation of a 3-point sluice-regulator, showed that a change in the angle of the bell and the energy parameter within 1.5...4.5 does not affect the nature of the longitudinal and transverse distribution diagrams of the average pressure in the bell and behind it. As a result, universal schemes of static loading by a vertical averaged load from a surface flow have been developed. In the discharge channel and on the slopes, the pressure fluctuation occurs mainly due to surface disturbance; therefore, a low-frequency component is traced on the autocorrelation functions, which also determines the spectrum's shape. It is proved that when constructing a quasi-static loading of plates by an instantaneous pulsating load for an expanding water break with triangular spreaders and checker-type dampers, it is possible to correctly use the longitudinal and transverse correlations corresponding to spatial turbulence and on the apron-homogeneous. The maximum amplitude of the pulsating load on plates of any size should be calculated with a transition coefficient equal to approximately 3.85 for apron plates and no more than 4.5 for water breakage. The results obtained make it possible to perform the entire complex of calculations to assess the stability of various elements of the downstream structures of the considered typology.

Introduction to Cartan numbers and some geometric applications

This article aims to define the rotational motion around a lightlike axis in pseudo‐null or null frames more easily and to put forward a suitable number system to express rotation transformation in these frames. Therefore, for null and pseudo‐null frames, we define a new set of numbers consisting of a linear combination of two lightlike units and a spacelike unit, which we call Cartan numbers. The first part gives the properties of the set of Cartan numbers, and in the second part, some geometric definitions, theorems, and applications are given. In addition, the definition of the center of a parabola and the concept of the central angle are defined. The connection is made between these concepts and the parabolic rotation transformation. Rotation matrices for parabolic rotations are obtained. The rotating points indicated that it follows in which cases a line path and in which cases a parabolic path. The rotation transformation along any straight line or parabola is studied with examples.

The Effect of the Central Angle and Height of Arced Piano Key Weir on the Discharge Coefficient

The Effect of the Central Angle and Height of Arced Piano Key Weir on the Discharge Coefficient

Large deformation and failure analysis of the corrugated flexible composite skin for morphing wing

The morphing wing has been a research hotspot in the aviation field in recent years, and the flexible skin is one of the most important parts of the morphing wing. The analytical method, experimental method and numerical simulation were employed in this paper to evaluate the tensile behaviour and functional mechanisms of a new corrugated Flexible Composite Skin (FCS). The FCS is composed of two thin-walled curved Fibre-Reinforced-Plastics (FRP) composite shells which can be extended and contracted through pure elastic deformation during the large deformation process. Based on equilibrium equations, classical laminate theory and the maximum stress criterion, the analytical model for predicting the tensile behaviour of the FCS was established. FCS specimens were fabricated using vacuum bag method. Tensile experiments of FCS specimens were performed, and complete tensile load–displacement curves and tensile failure loads were measured. In addition, a Finite Element Model (FEM) was established to predict the tensile behaviour of the FCS. Prediction results using the analytical model and the FEM were compared with experimental results, and the three were in good agreement. Finally, the effect of geometric parameters (i.e. radius of curvature, center angle and thickness) on the tensile behaviour of the FCS was further investigated with the aid of the analytical model. It is shown that geometric parameters are one of the key factors affecting the tensile behaviour of the FCS.

Mitigating Structural Vibrations due to Earthquake with Application of Slope Bottom Tuned Liquid Dampers

Earthquakes are one of man’s most feared natural phenomena, producing almost instantaneous destruction of buildings and other constructed facilities. In order to mitigate damage of structures and save the life, various measures are adopted and use of structural control devices is one of them . Structural control devices can enhance the integrity of structures without increasing the dimensions of structural members. In this study, an attempt has been made to systematically investigate the performance of structural control device namely, tuned liquid damper (TLD) for controlling the dynamic response of reinforced concrete (RC) framed structure. Dynamic analysis of a 10 story RC framed structure with both flat and slope (W or central slope) bottom rectangular TLDs, subjected to five earthquake time histories have been performed. Key results have been presented in the form of tuning ratio, liquid mass reduction and displacement response reduction due to slope at bottom TLD. For the case of TLDs with central slope, the analyses have been performed for slope angle ranging from 5-14º. Based on the study, it has been observed that, tuning ratio of TLD decreases with increase of central slope at the bottom of TLD, the variation of liquid mass reduction with slope angle has been observed to be linear and reduction in displacement of structure increases with increase in central slope angle.

Theory of optical activity in doped systems with application to twisted bilayer graphene

We theoretically study the optical activity in a doped system and derive the optical activity tensor from a light wave vector dependent linear optical conductivity. Although the light-matter interaction is introduced through the velocity gauge from a minimal-coupling Hamiltonian, we find that the well-known ``false divergences'' problem can be avoided in practice if the electronic states are described by a finite-band effective Hamiltonian, such as a few-band tight-binding model. The expression we obtain for the optical activity tensor is in good numerical agreement with a recent theory derived for an undoped topologically trivial gapped system. We apply our theory to the optical activity of a gated twisted bilayer graphene, with a detailed discussion of the dependence of the results on twist angle, chemical potential, gate voltage, and location of rotation center forming the twisted bilayer graphene.

Analysis of cure-induced deformation of asymmetric C-shaped composite parts

This study seeks to explain the influence of the main geometric parameters on the asymmetric C-shaped composites’ curing deformation. A numerical model appropriate for cure simulation was described and verified through experiments. Then, the model was used to evaluate the influence of different parameters instead of experiments. It was found that the mold’s radius has the most significant effect on the deformation. Apart from the central angle, all other parameters have a similar impact on the twist angles. While the in-plane twist angle constantly increases in relation to the center angle, the out-of-plane twist angle initially increases and then drops.

Soft Contact Lens With Embedded Moiré Patterns-Based Intraocular Pressure Sensors

Soft contact lenses with built-in sensors have shown great potential for real-time monitoring of intraocular pressure (IOP). This paper reports a contact lens IOP sensor based on the moiré patterns. One concentric ring grating (G1) is fabricated on a commercial contact lens, the other line grating (G2) is stored in a computer. Images of G1 are captured using a smartphone camera. Then moiré patterns are generated by superimposing the images of the two gratings in a computer. The central angle <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\theta $ </tex-math></inline-formula> formed between two innermost adjacent moiré patterns is extracted as the IOP transducing signals. The performance of the sensor has been evaluated using a home-made hollow hemispherical silicone model eye. The sensitivity of the contact lens IOP sensor is ~0.15°/mmHg with high repeatability. Additionally, the sensor sensitivity is essentially independent of the initial IOP exerted on the contact lens. Furthermore, the virtual G2 provides great flexibility for the design and fabrication of the sensor, the fabrication of G1 directly on commercial contact lenses paves the way for clinic use. All these results indicate the suitability of this type of sensor for monitoring IOP. [2022-0111]

An Ultra-Wideband Multilayer Absorber Using an Equivalent Circuit-Based Approach

An ultrawideband (UWB)absorber designed by equivalent circuit model (ECM) is presented in this article. The structural parameters of multilayer absorbers were calculated for full-wave simulation so as to verify the accuracy of this method. The simulation results illustrated that the ideal frequency response can be easily and quickly obtained by using ECM, such as single narrow absorption band, dual-band absorption peak, and ultrawide absorption band. A <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$20\times20$ </tex-math></inline-formula> quadruple-layer absorber was fabricated and tested, which obtained 10 dB radar cross Section reduction (RCSR) from 2.1 to 37.5 GHz with bandwidth ratio (BWR) of 17.62:1. The overall dimension of the unit cell structure is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$280\times 280\times 14\,\,{\mathrm{ mm}}^{3}$ </tex-math></inline-formula> ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.96\lambda _{\max } \times 1.96\lambda _{\max } \times 0.098\lambda _{\max } $ </tex-math></inline-formula> ), and the absorber exhibits stable response on conformal cylinders with central angles of 30° and 60°. Moreover, in order to reduce the influence of high-order modes above U-band, the space mapping (SM) technique was introduced to optimize the absorber’s parameters, which greatly expanded the high-frequency absorption bandwidth. A 10 dB RCSR was achieved from 3 to 94 GHz with BWR of 31.33:1.

Morphometric and volumetric analysis of the proximity between the incisive canal and maxillary central incisors during anterior retraction: a retrospective cone-beam computed tomography study.

To elucidate the relationships and factors affecting the proximity between the incisive canal (IC) and maxillary central incisors and to predict the probable outcomes after anterior tooth retraction using cone beam computed tomography (CBCT). Retrospective CBCT data taken before and after maxillary anterior retraction in 36 patients were used in this study. The incisive canal length (ICL), maxillary central incisor length (TL), angles between the palatal plane and axes of the maxillary alveolar border (θ1), IC (θ2), and maxillary central incisor (θ3), retraction distance (TDE), distance from the maxillary central incisors to the IC (D), cross-sectional area of the IC (CSA), and volume of the IC were evaluated. Comparison of the parameters between contact and noncontact groups were examined. Logistic regression was performed to analyze the probable outcome prediction. All parameters significantly decreased after anterior retraction, except for the ICL. Eighteen roots in 12 patients contacted the IC. The θ1, θ2, θ3, and D values at all levels were significantly lower, whereas the TDE, midlevel and oral opening CSA, and volume were significantly higher in the contact group compared with the noncontact group. The larger the pretreatment θ1 and θ3 were, the higher was the chance of incisors not contacting the IC. Maxillary central incisors not contacting the IC after anterior retraction was positively associated with larger degrees of pretreatment maxillary alveolar bone angle and maxillary central incisor angle.

Watchful waiting for the undisplaced hip dysplasia when undergoing contralateral hip reconstruction.

Patients undergoing surgical reduction of the dislocated hip secondary to developmental dysplasia may have a contralateral undisplaced dysplastic hip. This study aimed to compare the observation of the contralateral undisplaced dysplastic hip with the treatment by acetabuloplasty in terms of persistent dysplasia to determine the need for bilateral surgery. Acetabular dysplasia was defined by an acetabular index (AI) of more than 30 degrees plus a center edge angle (CEA) of less than 20 degrees. A surgical database was queried retrospectively for a cohort between 2008 and 2016. Inclusion criteria were aged between 1 and 6years, unilateral developmental dysplasia (international hip dysplasia institute grade 1) with contralateral dislocation, no previous treatment and a minimum follow-up of 1 year. Fifty-seven patients were included, 40 in the observation group and 17 in the acetabuloplasty group. The mean age (interquartile range) was 20 (17-23) months, and the mean follow-up was 42 (22-62) months. The baseline values were similar for both groups. At the final follow-up, no hip had dysplasia, as specified a priori in either group, but the final AI and CEA were corrected more in the acetabuloplasty group (p < 0.001). Based on the adjusted analysis, both acetabuloplasty and follow-up without treatment were associated with improved acetabular coverage. Watchful expectancy of undisplaced hip dysplasia presenting in patients undergoing contralateral hip reconstruction during years of acetabular growth is safe as the risk of persistent dysplasia and additional surgery is low. III.

Improving Thickness Uniformity of Amorphous Oxide Films Deposited on Large Substrates by Optical Flux Mapping

In this study, three amorphous oxide thin films are prepared by an electron beam evaporation combined with ion-assisted deposition technique. With the aid of optical flux mapping method, thin film thickness distribution with good uniformity can be obtained by appropriate coating masks. Three metal oxide single-layer thin films are SiO2, Ta2O5 and Nb2O5, respectively. These thin films were deposited on a substrate holder with a radius of 275 mm that was divided into five different segments. Based on the optical flux mapping method, we can effectively simulate the geometric dimensions of the coating mask and obtain the width of the coating mask at different segments. If the film thickness uniformity is a function of masking area and center angle, it is necessary to determine the thickness distribution of the different segments and use a surface profiler to accurately measure the film thickness. We analyzed the thickness uniformity of three oxide films deposited at five different segments. The experimental measurement results show that the deviation of thickness uniformity is 0.38% for SiO2, 0.36% for Ta2O5, and 0.15% for Nb2O5 thin films, respectively.

Feasibility of Onboard Smartphones for Railway Track Geometry Estimation: Sensing Capabilities and Characterization

The performance and sensitivity of smartphone sensors developed rapidly in recent years. Due to their accessibility and low costs compared to other industrial solutions, the use of smartphone sensors has become more and more common. In this article, the validity and reliability of a smartphone application in railway track geometry estimation are tested on a conventional rail line. This work focused on Galaxy S-series smartphones of Samsung and proposes an evaluation of the onboard sensing capabilities of their inertial sensors with the comparison of synchronous measurements by a multi-functional Track Recording Vehicle equipped with a contactless Track Geometry- (TGMS), and a Vehicle Dynamic Measuring System (VDMS). The raw accelerometer recordings showed a high-degree correlation with VDMS in both signal magnitude and waveform. The accuracy of gyroscope angular tracking in heading and pitching angle calculation was in the range of 0.2°–0.6°, which allowed the acceptable estimation of the central angle and the radius of horizontal curves. Based on the kinematic analysis techniques, the roll flexibility coefficient of the vehicle was determined, which allowed calculating the cross-level and the twist of the track. Furthermore, the local extreme values of the roll-rate gyro correlate with the isolated track geometry defects of the track twist gathered by TRV’s TGMS. Despite its limitations, the application of smartphones represents a prospective technological opportunity to explore new approaches and support rail asset management.