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The paper presents a research of angular orientation based on a Microelectromechanical System (MEMS) accelerometer by using machine learning (ML) and deep learning (DL) model with architectures of deep neural networks (DNN). In the industrial environment, Artificial Intelligence (AI) plays a crucial role in automation which is a potential solution for better performance of inclinometer. This research was carried out to apply this intelligent model on the Inertial Measurement Unit (IMU) to accomplish the angular position. The experiment shows that the ML model correctly learns the relationship between acceleration and tracking angles via polynomial regression with an R-square of 0.99. The employed DL model with 4 hidden layers of 10 neurons achieves an accuracy of 99.99 \% and almost non-error performance. The acceleration acquisitions were obtained from MEMS accelerometer LSM9DS1 at a frequency of 50 Hz via microcontroller STM32F401RE. The ML and DNN model were designed based on platform Tensorflow with high processing accuracy. The Pan-Tilt Unit was used as the angle reference for static and dynamic tests. The traditional technique is used for comparison as well as verification of the proposed models. DL model has better precision over the ML model due to its high structure level with updating weight and error optimization from the neural network structure. Meanwhile, MC shows more stable results in dynamic circumstances.

BACKGROUD: Reliable scapular upward rotation and anterior-posterior tilt data are required for patients with subacromial impingement syndrome (SIS). Only a few studies have explored the reliability of such measurements derived using a modified inclinometer. OBJECTIVES: To determine the relative and absolute reliability of scapular upward rotation and anterior-posterior tilt measurements derived using a modified digital inclinometer in patients with SIS. METHOD: Seventeen SIS patients were assessed twice within 1 week. We determined the relative and absolute measurement reliability by calculating the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimal clinically important difference (MCID). Both intra- and interrater reliability were determined. RESULTS: The intra-rater reliability (both measurements) was high (0.72–0.88), and the interrater ICC was high to excellent (0.72–0.98). Clinically acceptable SEM and MCID values were obtained for scapular upward rotation (SEM: 4.28–9.33∘, MCID: 5.1–11.3∘) and anterior-posterior tilt (SEM: 3.72–7.55∘, MCID: 2.5–10.8∘). CONCLUSIONS: Measurements of scapular upward rotation and anterior-posterior tilt using a modified digital inclinometer reliably reveal scapular position and kinematics in patients with SIS.

Background/aim Anterior cruciate ligament (ACL) injuries cause mechanoreceptor loss in the joint; therefore, proprioceptive deficits are observed after injury. In particular, proprioceptive measurements made in the functional position give more accurate results, and this is an area that requires further studies. This study aimed to evaluate proprioception in patients who had undergone ACL reconstruction (ACLR) in functional positions used in daily life (closed kinetic chain position), according to joint angles where ACL injuries occur more frequently, in comparison with healthy controls. Materials and methods Thirty-four participants who underwent ACLR using a hamstring tendon graft (aged 29.18 ± 8.16 years; body mass index (BMI), 26.58 ± 4.02 kg/cm2) and 31 healthy participants (aged 27.35 ± 5.74 years; BMI, 24.76 ± 2.98 kg/cm2) were included. Proprioception was assessed with an active angle repetition test, using an inclinometer in the closed kinetic chain position while standing. Participants were asked to perform single-leg squats until the angle at the knee joint was 30°. After the targeted angle was defined, the participants were asked to find the targeted angle. The difference between the targeted angle and the angle reached by the participants was calculated. Results A statistically significant difference in the active joint position sense was found among the ACLR extremity, uninvolved extremity, and control extremity (p < 0.05). The proprioceptive sense between the two extremities in the ACLR group was similar, and the proprioceptive sense was worse than that of the control group. Conclusion To our knowledge, this is the first study to evaluate closed kinetic chain position in patients who underwent ACLR, and it showed that proprioceptive sense was still poor in patients with ACLR compared with the control group, even if an average of 24 months have elapsed since surgery.

Most of the dam’s disasters that occurred in the world could be avoided if proper and preventive measures were taken, such as long-term surface or underground monitoring to detect small soil displacements. However, due to the complex operation necessary to monitor underground layer displacements, inclinometers are not used with suitable regularity. To circumvent the logistics of field campaigns necessary in conventional inclinometers, a real-time, remote monitoring system was developed. In this paper, a fiberoptic inclinometer system was designed, consisting of FBGs arrays fixed along a flexible tube to be inserted into conventional boreholes to monitor underground layers displacements. Tests on the bench consisted of applying lateral displacements to curve the tube with the Bragg wavelengths acquired by an FBG interrogator. Then, a specially developed algorithm, applying the Frenet-Serret equations, and the cubic spline interpolation method were used to reconstruct the tube profile. For the first validation of the proposed method, the algorithm was applied to real data obtained in-field by a conventional inclinometer. The results of these tests showed a good agreement between the curve reconstruction and the plotted data of field measurements. The final validation was performed by applying lateral displacements to the instrumented tube and comparing the real tube profile measured by a laser ruler with the calculated profile by the algorithm. The errors found in all tests were less than 1% attesting that the proposed system can be an alternative methodology to the conventional techniques of geotechnical instrumentation, through continuous monitoring with fast response and in real-time, with possible application to quantify the mass movement of soils; movements from earth dams, landfills, and slopes.

Context: Technological advances have given smartphones the capabilities of sensitive clinical measurement equipment at lesser cost and higher availability. The Clinometer is a smartphone application that can be used to measure the joint range of motion in a clinical setting, but psychometric properties of the tool’s use measuring cervical range of motion (CROM) are not established. Objectives: The purpose of this study was to examine the validity and intrarater reliability of the Clinometer application for the measurement of CROM (ie, flexion, extension, rotation, lateral flexion) and to determine the minimal detectable change and SEM. Design: A blinded, repeated-measures correlational design was employed. Setting: The study was conducted collaboratively between 2 athletic training clinics. Participants: A convenience sample of healthy adults ages 18–30 years were recruited. Participants with any history in the last 3 months of cervical or thoracic pathology, pain, or any musculoskeletal injury were excluded. Main Outcome Measures: Three repetitions of each motion were measured by a primary researcher with a goniometer. The same researcher then conducted 3 blinded measurements with the Clinometer application following the same procedure. A second researcher, blinded to the goniometer measurements, recorded the results. Thirty minutes later, testing was repeated with the application. The Pearson correlation was calculated to determine validity of the application compared with goniometry. Results: The measurements between devices had moderate to excellent concurrent validity, with the coefficients ranging between 0.544 and 0.888, P Conclusion: The Clinometer application is a valid and reliable instrument for measuring active CROM. Level of evidence: clinical measurement, level 1b.

Background: This paper outlines a summary of examination technique to identify the range of movement of the cervical spine. Due to common difficulties in obtaining tools for cervical examination within the district, a standardised compilation of easy-to-replicate examination techniques are provided using different tools. Methods: Bedside instruments that can be used includes a measuring tape, compass, goniometer, inclinometer and cervical range of motion (CROM) instrument. Discussion: Cervical flexion-extension, lateral flexion and rotation will be assessed with bedside instruments. This would aid in increasing accuracy and precision of objective measurement while conducting clinical examination to determine the cervical range of motion.

With the development of horizontal Wells and extended reach Wells in the field of oil and gas exploitation, it is of great significance to the development of MWD which can measure the drilling trajectory in real time. Therefore, in recent years, Measurement while drilling (MWD) has been widely recognized and rapidly developed in the field of precise target drilling. Accelerometers and fluxgates are related to well trajectory measurement in the MWD. The external environment and the processing and installation error of the sensor lead to some errors in the measured value. Deviation caused by environmental interference and installation error leads to the low control precision of drilling tool attitude. In view of the shortcomings of the current calibration methods and the time-consuming and complicated operation of the traditional tri-axis orthogonal inclinometer calibration, this paper proposes the attitude error calibration method of the MWD based on the support vector classifier and the K-proximity method. First, a neural network model is established based on the measured calibration results and the measurements errors. Then, the K-proximity method is used to further classify the drill tool attitude data, and a neural network model combining the K-proximity method is constructed. Secondly, the software and hardware experimental platform for on-line calibration of the slant meter while drilling is built by using the calibration frame and the geomagnetic sensor. Finally, the experimental results showed that the mean deviation of well inclination angle and tool face angle is controlled within ±0.2°, and the mean deviation of azimuth is controlled within ±0.5°, which verified that the algorithm can increase accurate of drilling tool attitude.

Objective This study aimed to determine the intra- and interrater reliability of active and passive range of motion in the shoulders of individuals with subacromial impingement syndrome using a digital inclinometer. Methods The raters evaluated active and passive range of motion in the shoulder of 50 individuals with unilateral subacromial impingement syndrome in movements including flexion, abduction, extension, external rotation in a neutral position, external rotation with the arm at 90° of abduction, and internal rotation with the arm at 90° of abduction. The tests were performed by 2 examiners on the same day, with a 10-minute interval, and were repeated by 1 examiner after a 2- to 4-day interval. Reliability was analyzed using the intraclass correlation coefficient (ICC2,3). Results There was moderate to excellent interrater (ICC2,3 = 0.50-0.95) and intrarater (ICC2,3 = 0.74-0.94) reliability. In the interrater analysis, the standard error of measurement (SEM) ranged from 4.1° to 10°, the percentage SEM (%SEM) ranged from 2% to 17%, and the minimum detectable change ranged from 9.5° to 23.4°. In the intrarater analysis, the SEM ranged from 4° to 9.2°, %SEM ranged from 3% to 14%, and the minimum detectable change ranged from 9.3° to 21.4°. Conclusion The digital inclinometer showed moderate to excellent reliability for measuring active and passive range of motion in shoulders with unilateral subacromial impingement syndrome.

Today, as structures with life expectancy of more than 100 years are being constructed, it is vital to gain knowledge about the gradual decline in material properties. Accordingly, to ensure the longevity and safety of these structures, monitoring has been incorporated as a fundamental part of their service life. To monitor structural deformation, various methods have been developed, with the most common being the survey of certain points of a structure during and after construction using a total station. New techniques are now being developed, and one of the most promising ones is photogrammetry because it provides a simple method to monitor a structure using unmanned air vehicles (UAVs). This paper is aimed at sharing the strategic steps followed in monitoring the deflection of a simple secant pile retaining wall during excavation and construction of a basement. The monitoring is performed using a commercial UAV in combination with point cloud formation, georeferencing, and comparison software (cloud compare, I-Site Studio, 3D Reshaper, etc.). The monitoring results show very good agreement with the traditional inclinometer deflection measurements and numerical analysis, thereby demonstrating the feasibility of the proposed method. The authors believe that in the future, photogrammetry using UAVs can become the standard method for geotechnical monitoring because of its speed, lower cost and ease of use, when compared to conventional methods, a non-destructive method, and is easy to learn and use.

Spatial quasi-static and dynamic problems of the theory of elasticity, simulating the behavior of lithospheric plates and blocks of Earth’s crust are solved for a layered package. According to the data of seismic stations, GPS, inclinometers, and other measuring instruments, slow (age-related) and transient motions of lithospheric plates are considered. It is shown that by carrying out regular measurements, based on the obtained solutions, it is possible to trace the entire process of preparation and occurrence of earthquakes.

The track line suffers from track irregularity, subgrade settlement, rail surface defects, and gauge distortion. Measuring the track geometry quality plays an important role in rail administrations to safe operation and track maintenance. In order to meet the requirements of track daily inspection, this article describes a comprehensive detection system for the track geometry, which is designed by four cameras, an inclinometer, and an inertial measurement unit. Moreover, the detection system has the characteristics of simple structure, automatic detection, and multiple measurement parameters. First, to measure track alignment and irregularity, a multisensing calibration method is established to fuse visual sensors and inertial sensors. An accelerometer and a Kalman filter are used to eliminate accumulated unrealistic drifts of accelerometer and gyroscope. Second, to measure the rail surface defects and gauge, the model of laser and machine vision is deduced to obtain the coordinate values in a unified coordinate system, and an improved iterative closest point method is developed to improve the matching accuracy. Finally, a series of experiments is carried out to validate the measuring performance. The results indicate that the proposed method can accurately measure the track geometry, with the maximum deviations of track alignment, track irregularity, rail defects, and gauge that are less than 0.5, 0.4, 0.3, and 0.1 mm, respectively. The detection system is not only simple in structure but also has multiple detection parameters, which is especially suitable for track daily maintenance.

The conceptual new design of the Precision Laser Inclinometer (PLI) is proposed and developed what resulted in creation of compact instrument for its possible use in a restricted vacuum volume of sensitive elements of Gravitational Wave Interferometric Antennas. It is shown that the use of a position sensitive method—the dividing plates method—for the detection of angular inclination of laser beams, allows to reduce the dimensions of the PLI to a cube of 11 × 11 × 15 cm3 or to a cylinder with a diameter of 15 cm and a height of 11 cm. The reduction of the dimensions results in a simultaneous increase of 1.9 times in the sensitivity of recording the angular inclinations of the earth’s surface.

For the Precision Laser Inclinometer (PLI) temperature resistivity increase the essential design innovations have been developed and introduced in the PLI accepted design scheme. The proposed methods of the temperature resistivity guarantee—as shown experimentally—the achievement of a long term PLI sensitivity of 2.8 × 10–11 rad for allowed ±0.1°С variation of temperature of surrounding environment.

Purpose Precise measurement of elbow range of motion (ROM) post-injury or surgery forms an important part of determining prognosis and the need for further intervention. Clinicians are increasingly incorporating smartphone use in our medical practice; we sought to determine if a smartphone goniometer application is a valid and reliable tool for assessment of elbow ROM in the paediatric patient, compared to visual and goniometer assessment. Methods In total, 20 paediatric patients (40 elbows) between six and 15 years of age with an elbow or forearm injury were included in this prospective series. Elbow flexion, extension, pronation and supination were measured independently by two orthopaedic clinicians. Measurements were taken from injured as well as unaffected side using a standardized technique, first with visual estimation and then using a universal goniometer (UG) and smartphone goniometer application Angle Meter via Google Play store (Smart Tool Factory, Istanbul, Turkey). Results There was excellent interobserver reliability for all three modalities, with average intraclass correlation coefficient (ICC) values greater than 0.90. Visual estimation had the lowest average ICC of 0.92, compared to 0.97 for UG and smartphone. Overall, there was excellent intraobserver reliability between the smartphone application and the gold standard UG for all elbow movements with ICCs ranging between 0.98 to 0.99 and mean absolute difference ranging from 1.1 ± 1.0° to 2.6 ± 1.9°. The smartphone application showed superior agreement over visual estimation when compared to the gold standard UG with lower mean differences and 95% limits of agreement (LOA) falling within 10°. Conclusions Our study demonstrates that a smartphone application is a valid and reliable assessment tool for measurement of elbow ROM in paediatric patients, and better than visualization alone. Level of evidence III

We report and demonstrate a high-resolution extrinsic Fabry–Perot interferometer (EFPI)-based 2-D fiber optic inclinometer for tilt measurements in two orthogonal dimensions. The inclinometer consists of a pair of perpendicularly arranged EFPI sensors packaged inside a rectangular container box. A triangular-shaped metal prism is attached to the top plate of the container box by three ropes with identical lengths. Two optical fibers are rigidly connected to the top plate of the container box by two supporting rods, respectively. Therefore, two EFPI sensors are formed between the endfaces of two optical fibers and their corresponding side face mirrors. The prism is connected to a cross paddle, which is immersed in a damping fluid to reduce the influence of deleterious vibrations. After tilting, the two reflectors of each EFPI sensor will remain parallel, while the cavity lengths of the EFPI sensors change. Changes in the cavity lengths can be calculated, and the 2-D tilt angles of the inclinometer can be calculated according to the Fabry–Perot principle. The design of the sensor and the measurement principles are discussed. Measurements of the tilt angles of a simply supported beam induced by small loads are presented to verify the tip-angle resolution and uncertainty of the two EFPI sensors in our 2-D inclinometer. The results show the capability for metering tilt angles with high resolution. The 2-D inclinometer was used to continuously monitor the tilt angle of a gravity dam for a one-year period, showing excellent stability and practicability.

Piles subjected to lateral loading can create problems in soil-structure interaction. Several differing methods of analysis have been proposed to solve the problem of laterally loaded piles, resulting in the determination of pile bending and the bending moment as a function of depth below soil surface. These piles are widely used to support laterally loaded piles, such as bridge pillars, offshore platforms, communication towers and others. This study presents an analytical solution to Miche’s problem as a continuous function of depth: deflection and moment, as well as a dimensional plots to be used in projects involving piles subjected to laterally loading only including data concerning laterally loading test and pile geometry. A new formula is presented to calculate the pile head displacement as well as an equation to determine maximum moment for a generalized Miche model and further analysis. In addition, this paper proposes an equation for the determination of constant horizontal subgrade reaction $$(n_{h})$$ based on the CPT in-situ test and the geometric characteristics of the pile. Calibration of the analytical model showed good fit and conservative results regarding inclinometer data from an bored pile and good agreement with the literature results.

The accuracy of landslide displacement prediction can effectively prevent casualties and economic losses. To achieve accurate prediction of the Majiagou landslide displacement in the Three Gorges Reservoir (TGR), China, a hybrid machine learning prediction model considering the deformation hysteresis effect is proposed. The real-time deep displacement measurements were captured by using in-place inclinometers with Fiber Bragg grating (FBG) sensors. The time series method was adopted to divide the total displacement into a trend term and periodic term. Trend displacement was determined by the geological condition and predicted by the fitting method. Periodic displacement was controlled by external factors such as rainfall and fluctuation of reservoir water level. Before making the prediction, the grey correlation analysis was adopted to confirm that the fluctuation of the reservoir water level was the main influence factor. In view of the deficiency that current prediction methods could not quantitatively determine the lag time of landslide deformation and thus select the influencing factors empirically, the dynamic analysis of the correlation between periodic influence factors and periodic displacement was carried out in this paper, and the deformation lag time was identified to be 18 days by using set pair analysis (SPA) method. Finally, the optimal influence factors were selected and the prediction model of Majiagou landslide based on support vector machine optimized by particle swarm optimization (SPA-PSO-SVM) was established. Results showed that the root mean square error (RMSE) and the mean absolute percentage error (MAPE) of the proposed SPA-PSO-SVM prediction model are 0.28 and 12.8, respectively. Compared with the PSO-SVM model, the prediction accuracy of the proposed model had been improved significantly. The reliability and effectiveness of the SPA-PSO-SVM prediction model is verified and it has apparent advantages while predicting landslide displacement with deformation hysteresis effect involved.

We demonstrated an all-fiber 2-D inclinometer based on fiber Bragg gratings with the capability of measuring the azimuthal angle and the inclination angle, simultaneously. The sensor performance is theoretically optimized and experimentally investigated. Excellent agreement between simulated and experimental results was achieved. Through detection of the wavelength shifts of the fiber Bragg gratings inscribed in the central core and two outer cores of a seven-core multi-core fiber, minimum error of 0.0056° for the azimuthal angle, and 0.025° for the inclination angle, were obtained. The detection range of the former ranges from 0 to 360°, while the latter ranges from 0 to 90°. The fiber Bragg grating in the central core can be used for temperature-compensation. The proposed fiber sensor is easy to fabricate and robust, increasing its potential in practical applications.

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.

Bharatanatyam is a popular classical and traditional dance of India. The dance’s postures and repetitive movements may affect loading on the spine. This study was undertaken to establish the relationship between the lumbar spine and pelvic tilt on abdominal muscle endurance in Bharatanatyam dancers. A secondary aim was to determine the effect of other recreational activities on these variables. We assessed 35 trained Bharatanatyam dancers, aged between 18 to 35 yr, who had at least 3 yr of training. Lumbar curvature and pelvic tilt were measured using a bubble inclinometer and palpation meter (PALM), respectively, and abdominal muscle endurance was tested using McGill’s core-endurance test. Spearman’s coefficient of correlation was used to determine relationships between variables. Mean lumbar curvature measured 48.00 ± 8.5, right pelvic tilt 10.83 ± 4.9, and left pelvic tilt 11.20 ± 4.8 degrees. The hold time that dancers could perform in McGill’s core-endurance test was 360 (225–257), 33 (16–55), 21 (18–34), and 24 (17– 34) s for flexor, extensor, right lateral, and left lateral test, respectively. No significant correlation was found between the three variables tested: lumbar curvature, pelvic tilt, and abdominal muscle endurance. The left lateral endurance test was significantly different (p = 0.04) in Bharatanatyam dancers who were involved in other recreational activities such as sports and yoga compared to those who were not involved in these activities.

In this chapter, an introduction of navigate a vehicle autonomously, the control action of the system must know at least two things, its own current position and direction of movement. Location can be find by either from an outside system source with technology such as the Global Positioning System (GPS), or by calculation of mathematical equation a followed path from a known source point with the use of electronic compasses, inclinometers, and rotational counters. However, under any scheme, the outcome is to somehow generate the positional information of the vehicle so that the vehicle could be guided to follow a path and reach the target. In addition of this, the direction sensing devices are also used for getting the values of current heading of vehicle so that it could be steered to move towards target location. GPS has advantage over other position detection mechanism that it also provides an estimate of vehicle’s current heading based on the previous two positional coordinates. While the current heading provided by GPS is not accurate enough under some conditions, it is envisaged to accommodate GPS as the only sensor for guiding the autonomous vehicle to follow the trajectory in outdoor applications

Considered current issues of automatic monitoring of high-rise buildings. A review of currently implemented monitoring methods is given. An analytical study of the effect of the ratio of the rigidity of the vertical and horizontal structural elements of buildings of various structural systems on the deformation of the vertical axis of the building was performed. The basis of the research is the solution of the differential equation of the elastic vertical axis of the building. By finding the extrema of the deformation function of the vertical axis, critical points of control of its angles of rotation are determined. As a result of the study, it was concluded that it is advisable to minimize the number of control points, with limited control at certain critical points. The position of the control points dividing the vertical axis of the building through ¼ of its length at the corners of the perimeter of the floors has been determined. It is shown that minimization is necessary due to difficulties in processing and analyzing big data (Big Data). As a result of the traditional manual calculation with the accepted design methods, it was found that the box-barrel structural system has the greatest deformations, the frame-link frame with the stiffness core has the smallest deformations, and outriggers do not always allow to radically increase the building stiffness. Studies were conducted on computer models of the same types of buildings, which confirmed this dependence. However, here the maximum rigidity was shown by the cross-wall model. This testifies to the features of modeling buildings in various ways and confirms once again the need to monitor not only high-rise buildings, but all non-standard ones. It is concluded that it is necessary to accumulate data on the deformations of buildings using automatic monitoring methods. It is shown that information on the technical condition of the building is complemented by information on the longitudinal deformations of vertical structures - columns, stiffness cores, measured by tensiometers on concrete, as well as dynamic stiffness, determined by the natural oscillation frequency of accelerometers. The principle of sensor grouping and the need to use integrated, integrated monitoring are shown.

This work proposes a novel, highly sensitive, and simple structure based on a tapered polymer as a tilt fiber sensor to sensitively measure tilt angles (θ).The fiber-optic tilt sensor consists of a tapered polymer and single-mode fibers (SMF), into which the tapered polymer to generate a bent in the sensor that is strongly correlated with θ. The used tapered polymer in the tilt sensing is the temperature (T) insensitive. It is further combined with a general fiber Bragg grating (FBG) as a temperature indicator for achieving simultaneous measurement of inclination (θ) and ambient T. The endface of the fiber is coated with a gold film to increase the light reflectivity and improve the measurement range. Experimental results show that when the sensor tilts, the reflective optical power changes significantly with high sensitivity, and the peak wavelength of FBG shifts when T varies. Both parameters can be measured simultaneously with good discrimination. An average tilt angle sensitivity of approximately 4.23 dB/deg. and a high resolution of 0.009 deg. are achieved in a θ variation from -6 to +6 deg. Simulations were performed and the numerical results were in good agreement with the experimental measurement.

Accurately measuring the mechanical power of wind turbines is essential for determining their efficiencies. As there is currently no standardized method available for a traceable mechanical power measurement of wind turbines, we propose a 10 MW mechanical power transfer standard based on a 5 MN·m torque transducer and an inclinometer for rotational speed measurements up to 20 min−1. In particular, the deviation of using an inclinometer is investigated both in simulation and experiments, and a compensation method is proposed. By tracing both the torque and the rotational speed measurements to national standards, it can offer a mechanical power measurement with 0.5 % measurement uncertainty.

Slope failures and landslides pose serious geotechnical challenges, as large fatalities and economic losses may occur due to such natural disasters. Landslides happen mainly due to excessive rainfall and large magnitude earthquake. In recent years, efforts have been made toward developing various early warning systems for landslide forecasting, which would help to minimize fatalities, by efficient evacuation, prior to the landslide event. The different methods/approaches for landslide forecasting include application of early warning sensors, acoustic emission-based slope alarm, displacement sensors, volumetric moisture content sensors, application of inclinometers and extensometers to monitor soil movement, Internet of Things (IoT) based monitoring system, micro electro mechanical systems (MEMS) based wireless monitoring and GPS based monitoring.

The intended scapular motion is a strategy to strengthen the lower trapezius (LT). However, few studies have explored the effects of the intended scapular posterior tilt motion on selective LT activation. Thus, the present study investigated the effect of the intended scapular posterior tilt on the electromyography (EMG) activity of trapezius muscles during prone shoulder horizontal abduction (PSHA). Eighteen asymptomatic men performed three types of PSHA: (1) preferred PSHA, (2) PSHA with the intended scapular posterior tilt, and (3) PSHA with the intended scapular posterior tilt and trunk extension. EMG activity of the upper trapezius (UT), middle trapezius (MT), and LT were measured during PSHAs. Scapular posterior tilt angle, with and without the intended scapular posterior tilt, were measured using inclinometer. The results indicated that LT muscle activity increased when scapular posterior tilt was applied with and without trunk extension (14–16%), compared to the preferred condition, during PSHA (p &lt, 0.05). However, the addition of trunk extension to PSHA with the intended scapular posterior tilt increased the UT muscle activity (28%) and the UT/LT (29%) and UT/MT (31%) ratios (p &lt, 0.05). The scapular posterior tilt angle was higher (15%) when applying the intended scapular posterior tilt (p = 0.020). These findings suggest that the intended scapular posterior tilt may be a useful strategy for selective LT muscle activation.

Background Body posture may be disordered by vestibular dysfunction, neurological disorders, problems with the distribution of muscle tone, brain injuries, and other dysfunctions. Growth hormone deficiency (GHD) can lead to many disorders, particularly of the musculoskeletal system. During treatment with recombinant human growth hormone (rhGH), an increase in muscle mass and an improvement in bone structure can be observed in children suffering from hypopituitarism from GHD. Methods The study involved 33 children suffering from hypopituitarism with GHD (9 girls and 24 boys), aged 10–14 years old. Measurements of the magnitude of their anterior–posterior spinal curvatures were made using an inclinometer. The children were examined at the medianus of the sacrum bone, the Th12–L1 intervertebral area, and the C7–Th1 intervertebral area. In order to characterize the anterior–posterior curvature of the spine, the results were compared with the general norms reported by Saunders. Statistical calculations were carried out using the statistical package Statistica 10 PL. Results Lumbar lordosis angles were higher in the patients currently receiving growth hormone (GH) treatment than in those who had yet to receive it. There is a statistically significant positive correlation between the length of growth hormone treatment and the alpha angle. There are also statistically significant correlations between age at the beginning of growth hormone therapy and the angle of lordosis. Statistically significant correlations were also seen between age at the beginning of growth hormone therapy and the alpha angle. Conclusions Although there may be changes in posture at the beginning of rhGH treatment, the sooner growth hormone therapy begins, the better the body posture. The longer the growth hormone treatment, the better the posture, as expressed by the alpha angle in the sagittal plane.

The introductory article is a review, the article examines and analyzes the latest research and publications on this issue, namely, engineering and geodetic monitoring of deformations of buildings and structures in the modern development of the construction industry. The introductory article discusses the main types of deformed state of engineering structures, considers the problem of monitoring ground masses. The basic methods of geodetic monitoring of deformations of building structures in complex engineering geological conditions are presented. An extensive list of applications and the relevance of the development of geodetic monitoring of deformations is given. Common methods and instruments for geodetic deformation monitoring are considered: leveling, linear-angular measurements, automated geodetic systems - they are used for remote data acquisition and on-line, the implementation of laser scanning (terrestrial, air and automobile) and the process of complex shooting, using satellite navigation systems, stereophotogrammetry, the use of inclinometers in combination with geodetic instruments for monitoring engineering structures and soil masses. The advantages and disadvantages of modern geodetic monitoring methods are given.

Today, systems in which it is necessary to evaluate the parameters of the spatial orientation of objects are widely used . Examples of such systems are computer systems (CS) for drilling control during geological exploration, seismic hazard prediction systems, diagnostic systems in nuclear energy, and others. Such an assessment is carried out, as a rule, by the software and hardware components of the spatial orientation assessment (SHCSOA) included in specialized CSs and are intended for primary and secondary transformation of information. In this case, the bias of the orientation estimation determines the efficiency of the use of the CS. A number of SHCSOA works in difficult conditions, characterized by the presence of vibration and magnetic anomalies, instability of the temperature, etc., with severe restrictions on the size of the primary sensors (PS). An analysis of the existing PAKOPOs showed that the need to ensure the orientation estimation is sufficient for the needs of the practice leads to an increase in the resource of the CS as a whole, which significantly narrows their scope. This gives rise to a contradiction between the efficiency and resource intensity of SHCSOA and specialized CSs. Purpose. To resolve this contradiction, this paper proposes methods for the secondary conversion of measurement information, which can provide a given bias and increase the efficiency of assessing the spatial orientation of objects. Conclusion. By mathematical modeling of the PS, as well as by preliminary determination of the instrumental errors of the PS and the parameters of the external magnetic anomalies, methods of secondary processing of information are proposed that can significantly reduce the bias in the estimation of the spatial orientation of objects using SHCSOA as part of specialized CS.

In this study, a noncontact bending and torsional stiffness estimation model for automobile frames is proposed. The deformed shapes of an automobile frame during bending and torsional loading tests were determined based on the 3D displacements from motion capture system (MCS). The measurement results from the system and existing sensors, such as linear variable differential transformers (LVDTs) and an inclinometer, were compared. The vertical displacements from a total of 30 markers measured by the MCS can be used to define the 3D bending and torsional deformed shapes of the automobile frame. The test results confirmed that the stiffness estimation model based on MCS facilitates more detailed and accurate estimation of stiffness of the automobile.

This paper discusses the evaluation and testing of MEMS capacitive accelerometer (z-axis sensitive) fabricated using silicon-on-insulator (SOI) wafer. The accelerometer structure consists of highly conductive (p-type, resistivity: 0.001 Ω-cm) silicon proof mass (1000 μm × 1000 μm × 30 μm) suspended by four crab-like L-shaped beams (1150 μm × 30 μm × 30 μm) over Pyrex (7740) glass cavity (5 μm depth). Rest capacitance of the accelerometer structure is found to be ~ 2.1–2.25 pF range. Qualified accelerometer chips are packaged and sealed in lead less ceramic (LCC) package along with capacitive readout circuitry chip. Packaged accelerometer showed a scale factor sensitivity of ~ 47 mV/g in − 17–42 g acceleration range with 3% non-linearity. Corresponding cross-axis sensitivity also measured (2%) in full-scale range. Frequency response of the accelerometer showed a 3 dB bandwidth of 380 Hz. Resolution of the accelerometer is measured by an innovative technique involving inclinometer. Here, the device output is recorded at near vertical mounting tilt angle (θ ~ 90°) of inclinometer. Present accelerometer output can be resolved at the inclinometer measurement at 90° (output: 2.42662 V) and 89° (output: 2.42780 V) which corresponds to an acceleration resolution of ~ 17 mg.

The Earth surface inclinations recorded by the Precision Laser Inclinometer have been transformed to vertical oscillations using a specifically developed method. A method to calculate the space displacement of collider beams focuses is proposed to evaluate the effects of the surface waves propagation, taking into account: the length of the region of the beam focusing for collisions, the seismic wave frequency and the wave speed dependence on the frequency. It is shown that the beams focus divergence is measurable: for the LHC, with a 40-m long beam focusing path for collisions, in the frequency range above 1 Hz for the seismic surface wave; for the CLIC (first stage), with a 1.9-km long beam focusing path for collision, in the frequency range [0.1 Hz, 0.5 Hz], typical range of the micro-seismic peak. The data obtained shows the necessity of monitoring the seismic activity by using a network of Precision Laser Inclinometers.

The decreasing of the relaxation time for recovery of the horizontality of the surface of thin layer of the liquid in the cuvette is a new observed phenomenon caused by the meniscus influence in case of the cuvette small inclination. It was experimentally established that the time of reconstruction of the surface of 4 mm thick liquid layer in the cuvette of ∅5 mm at 0.5 µrad of calibration inclining is 0.082 ± 0.006 s. In this case the relative deviation from the liquid surface planarity does not exceed 7%. The physics explanation of the phenomenon observed is proposed. The taking into account of the time duration of liquid surface horizontality reconstruction in the Precision Laser Inclinometer has resulted in the widening of Inclinometer’s sensitivity range up to 12.3 ± 0.9 Hz. The data obtained could be used when seismoisolating of the research equipment.

In the Professional Precision Laser Inclinometer the noise origins were analyzed. The new efficient methodic of these noises taking into account was proposed and realized. The own (instrumental) noise 6 × 10–12 rad/Hz1/2 of the PPLI has been measured in the frequency range of [0.1 Hz; 1 Hz]. The minimal PPLI registered spectral density when analyzing of a daylong data was 2.4 × 10–11 rad/Hz1/2.

Purpose: To demonstrate the validity and reliability of a smartphone app to measure ROM after stroke.Materials and methods: Twenty-one stroke survivors with a diagnosis of stroke that affected the ...

In geotechnical engineering, the displacement response of a structure plays an important role in evaluating structural performance and the safety state. Fiber Bragg grating-based inclinometers are one of the most common, intelligent and efficient instruments for measuring the internal displacements of slopes for their obvious advantages including anti-electromagnetic interference, small size, higher precision and improved durability in harsh environments. However, slope internal deformation cannot be directly measured from fiber Bragg grating (FBG) sensors and needs to be obtained by converting the strain results of the FBG sensors to displacement information. This paper reviews the five most common strain-displacement conversion methods used in these FBG-based inclinometers categorized into the indeterminate beam theory method (IBTM), beam element method (BEM), difference equation method (DEM), trapezoidal integration method (TIM) and conjugate beam method (CBM). The FBG-based inclinometers in slopes are regarded as a cantilever beam structure and the deformation behaviors of the cantilever beam with different lengths and two bending types were investigated by using a finite element numerical simulation. Then the calculation performances of these strain-displacement conversion methods were analyzed by comparing the actual and predicted results, which demonstrate that the TIM and CBM are prominent owing to their highest calculation accuracy and broadest scope of application.

An optical fiber inclinometer based on non-reciprocal phase change effect in a single-mode fiber loop mirror (FLM) is proposed. The phase of light waves in FLM is controlled by two-phase shifters (PSs). The relationship between the inclination angles and phase differences of the two-PSs, and transmitted light power was derived by Jones calculus. The signature of the birefringence obtained through simulation on the output light has been confirmed by experimentation. From the results, it was found that when the birefringence of the two-PSs are different, two measurement sensitivities (17.07 × 10−3 deg−1 and 21.37 × 10−3 deg−1) can be realized with one angle measurement system. We also report a method for changing measurable ranges, and measurement sensitivity. Since the angle can be directly measured from the transmitted light power, the results of this work contribute to the realization of simple and low-loss inclinometers using standard single-mode fiber.

Sedentary behaviour (SB) is an independent health risk-factor and interrupting SB seems to be beneficial. SB is both defined by posture and intensity, thus objective measurement of postures remains a priority. The ActivPAL inclinometer (AP) has been used as a reference for postural estimation, but information on the validity of the Actigraph inclinometer (AG

Ground movements due to deep excavation may cause damage or loss of functionality to nearby building, especially in urban areas: embedded diaphragm walls between the new and the existing buildings can be effective in reducing these movements. The paper reports the results of an experimental and numerical study carried on a full-scale anchored piles diaphragm used to supporting deep excavation in urban area devoted to the new Library of the University of Enna “Kore”, Enna (Italy). Two piles, located in the central part of the diaphragm wall, have been instrumented with conventional inclinometer cases and embedded piezoelectric accelerometers. The experimental measurements recorded during the construction and in operation are reported and discussed in detail. Plane strain finite element analyses using the code PLAXIS 2D are presented in which the diaphragm was modelled to evaluate the geotechnical system behavior. It has been observed that this model allows for a satisfactory simulation of the displacement of the wall during the construction phases under a static loading scenario. The results in terms of horizontal displacements obtained by numerical modelling are in good agreement with those derived by measurements. Furthermore, on the basis of measured data, an empirical method has been used to evaluate the surface settlements, whose values guarantee a good safety threshold to the nearby building.

THE AIM of this study is to precise the diagnostics of lumbar lordosis in children at primary classes through applying the Digital Pelvic Inclinometer and to correlate the results with the Functional Test. METHODS. The screening examination involved 132 children with the average age 8, 7 from the beginning classes in Sofia. The lumbar lordosis was assessed through the Fuctional Test in all children during the period April - June 2016.. The DPI was applied for preliminary investigation in 25 children of measuring left and rigth pelvic inclination and therefore – torsion. RESULTS. The lordosis test is negative in 8 children and 16 are with functional lordosis. The mean value of the test with DPI - left sided, for healthy children is 7.1 degrees, and in children with functional lordosis is 10.90. The difference of 3.80 is statistically significant due to the value of T-Student criterion (t) of 2.63 at a critical value of 2.07. CONCLUSION. The results showed the correlation between the Digital Pelvic Inclinometer Test and the Functional Lordosis Test. Тhis study confirmed that the applying of the Digital Pelvic Inclinometer give an opportunity to precise the diagnostics of lumbar lordosis in children.

This paper presents the results of a 2017 study conducted by the National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Mining Research Division (PMRD), to evaluate the effects of longwall-induced subsurface deformations within a longwall abutment pillar under deep cover. The 2017 study was conducted in a southwestern Pennsylvania coal mine, which extracts 457 m-wide longwall panels under 361 m of cover. One 198 m-deep, in-place inclinometer monitoring well was drilled and installed over a 45 m by 84 m center abutment pillar. In addition to the monitoring well, surface subsidence measurements and underground coal pillar pressure measurements were conducted as the 457 m-wide longwall panel on the south side of the abutment pillar was being mined. Prior to the first longwall excavation, a number of simulations using FLAC3D™ were conducted to estimate surface subsidence, increases in underground coal pillar pressure, and subsurface horizontal displacements in the monitoring well. Comparisons of the pre-mining FLAC3D simulation results and the surface, subsurface, and underground instrumentation results show that the measured in-place inclinometer casing deformations are in reasonable agreement with those predicted by the 3D finite difference models. The measured surface subsidence and pillar pressure are in excellent agreement with those predicted by the 3D models. Results from this 2017 research clearly indicate that, under deep cover, the measured horizontal displacements within the abutment pillar are approximately one order of magnitude smaller than those measured in a 2014 study under medium cover. Keywords: Longwall, Deformations, Shale gas wells, Casing, Safety and health

This paper proposes an effective and convenient method to analyze slope stability in real time, which is based on fiber Bragg grating (FBG) sensors. First, a new type of FBG inclinometer is designed to capture the internal slope displacement variation considering temperature compensation, and an optimum displacement algorithm is selected by an experiment. Once the monitoring work is prepared, the potential slope slip surface is determined by monitored displacement in an optimization model based on the maximum displacement increment of the objective function. Finally, integral processing is used with the Bishop method to simplify the calculation, and a safety factor is estimated by the integral method. An experimental model test of homogeneous soil is conducted to verify the feasibility and reliability of the proposed analytical method and the FBG monitoring technique.

This paper proposes a liquid microelectromechanical system (MEMS) inclinometer sensor and reports its design, fabrication, and characterization. In the sensor, a liquid metal droplet moves inside an annular-shaped channel, driven by gravity. The position of the liquid metal is reflected by electrodes and the new tilting angle is obtained. A MEMS fabrication process has been developed, and characterisation of the sensor has been carried out. Experiments show that the sensor has a resolution of 3.625° and a wide measuring range of ±45°. In comparison with solid MEMS gyroscopes, the proposed liquid sensor has advantages of fewer manufacturing steps and low costs. Beside, its resilience against impact is outstanding. Its sensitivity and accuracy are more than sufficient for hand held electronics, which are the main targeted applications of the proposed liquid sensor.

The objective of this study was to develop and evaluate a series of quality assurance (QA) techniques based on Octavius 4D phantom for testing of respiratory-gated treatment delivery, integrity of dose rate vs gantry speed in volumetric-modulated arc therapy (VMAT) commissioning, and multileaf collimator (MLC) positioning accuracy of a linear accelerator. An Octavius 4D phantom capable of rotating with the gantry and recording the detector signal with a sampling rate of 10 Hz was isocentrally set up and an inclinometer was also installed to measure the gantry angle simultaneously. A simple arc test was created and delivered with gating function activated to measure the timing accuracy of the gating window. A tailor-made dose rate vs gantry speed plan was also designed to test the accuracy of measured dose rate, gantry speed, and actual control points. All experiments were conducted while machine log files were collected for comparison. The variations of beam flatness, symmetry, and field size were analyzed as a function of gantry angle to evaluate the influence from the modulation of dose rate and gantry speed. MLC position accuracy was evaluated based on specific garden fence plans. The time of gating window was measured to be less than 10-millisecond deviation from the log data. Gantry backlash was observed and quantified to be 1.72° with an extra stabilization time of 1.16 seconds for a gating arc with gantry speed of 6°/s. In the dose rate vs gantry speed test, the mean deviation between measured gantry angle and log data was less than 0.2° after a time delay of 0.25 second was corrected. The measured dose rate agreed with the log data very well with a mean deviation of 0.05%, and even the transit of modulation was tracked successfully. There was a statistically significant difference on the variation of beam parameters between a VMAT plan and a simple arc plan. The induced MLC position errors were detected with an accuracy of 0.05 mm. The leaf position reproducibility was found to be better than 0.02 mm, whereas the routine MLC position accuracy was better than 0.1 mm. A time-resolved method using Octavius 4D phantom has been developed and proven to be convenient for respiratory gating QA, dose rate vs gantry speed test, and MLC QA. Gating time, dose rate, and gantry speed-induced leave position error could be directly measured with high accuracy after comparison with the machine log data. This study also highlights the capability of the phantom in quantifying the variation of flatness, symmetry, and field size during gantry rotation.

Background Research supports that moderate-to-vigorous intensity physical activity (MVPA) is key to prolonged health and function. Among older adults, substantial changes to MVPA may be infeasible, thus a growing literature suggests a shift in focus to whole-day activity patterns. Methods With data from 795 older adults aged 65–100 in the Adult Changes in Thought Activity Monitoring study, we used linear regression to estimate associations between ActiGraph and activPAL measured activity patterns – including light intensity physical activity, steps, standing, and sedentary behaviors – and physical function as measured by a short Performance-based Physical Function (sPPF) score (range 0–12), a composite score based on three standardized physical performance tasks: gait speed, timed chair stands, and grip strength. We examined whether relationships persisted when controlling for MVPA or differed across age, gender, or quartiles of MVPA. Results In models unadjusted for MVPA, a 1-standard deviation (SD) increment of daily sitting (1.9 h more), mean sitting bout duration (8 min longer average), or time spent in sedentary activity (1.6 h more) was associated with ~ 0.3–0.4 points lower mean sPPF score (all p Conclusions We found associations between function and activity metrics other than MVPA in key subgroups, findings that support research on broader activity patterns and may offer ideas regarding practical intervention opportunities for improving function in older adults.

We demonstrate a new concept for an all-fiber inclinometer based on a tapered fiber Bragg grating (tFBG) in a fiber ring laser (FRL) with the capability of measuring the tilt angle and temperature simultaneously. The sensor performance is analyzed theoretically and investigated experimentally. The dependence of tilt angle on the spectral response in variable temperature conditions was measured. Two inclinometers with different lengths have been fabricated and characterized in FRL. The sensitivity is 0.583 dB/° and 0.849 dB/°, respectively, in the range of 0° to 90°. Thanks to the FRL system, narrow 3-dB bandwidth (&lt, 0.1 nm) and high optical signal-to-noise ratio (~60 dB) are achieved. The tFBG in the FRL system can be used for working as a temperature insensitive inclinometer. The results suggested that the proposed inclinometer has the advantages of compact size and convenient manufacture, enhancing its potential for application prospect.

Objective Frontal plane knee alignment plays an integral role in tibiofemoral knee osteoarthritis development and progression. Accessible methods for obtaining direct or indirect measures of knee alignment may help inform clinical decision making when specialized equipment is unavailable. The present study evaluated the concurrent validity, as well as intersession (within-rater) and interrater (within-session) reliability of smartphone inclinometry for measuring static frontal plane tibial alignment—a known proxy of frontal plane knee alignment. Methods Twenty healthy individuals and 38 patients with knee osteoarthritis were measured for frontal plane tibial alignment by a pair of raters using smartphone inclinometry, manual inclinometry, and 3-dimensional motion capture simultaneously. Healthy participants were measured on 2 separate days. Bland-Altman analysis, supplemented with intraclass correlation coefficient (ICC)(2,k), was used to assess concurrent validity. ICC(2,k), SEM, and minimum detectable change with 95% confidence limits (MDC95) were used to assess measurement reliability. Results Compared against motion capture, smartphone inclinometry measured frontal plane tibial alignment with a mean difference of 0.7 and 1.1 degrees (biased toward varus) for healthy participants and participants with knee osteoarthritis, respectively (ICC[2,k] ≥ 0.87). Smartphone inclinometry measurements demonstrated adequate intersession (within-rater) relative (ICC[2,k] = 0.91) and absolute (SEM = 0.7 degrees; MDC95 = 1.8 degrees) reliability, which outperformed manual inclinometry (ICC[2,k] = 0.85; SEM = 1.0 degrees; MDC95 = 2.6 degrees). Interrater (within-session) reliability of smartphone inclinometry was acceptable in both cohorts (ICC[2,k] = 0.93; SEM = 0.4 degrees to 1.2 degrees; MDC95 = 1.2 degrees to 3.2 degrees). Conclusion Smartphone inclinometry is sufficiently valid and reliable for measuring frontal plane tibial alignment in healthy individuals and patients with medial tibiofemoral knee osteoarthritis. Impact Smartphones are readily accessible by clinicians and researchers. Our assessment of measurement validity and reliability supports the use of smartphone inclinometry as a clinically available tool to measure frontal plane tibial alignment without medical imaging or specialized equipment.