Rotation Sensor Research Articles

Development and flight-test verification of two-dimensional rotational low-airspeed sensor for small helicopters

This paper describes the development and the verification of flight test results of a differential pressure-based, two-dimensional low-airspeed sensor designed for the navigation or disturbance detection in small helicopters. The compact and lightweight sensor is integrated with the main rotor of a small helicopter and comprises two probes at both arm ends, a differential pressure sensor, rotary encoder with one magnet and two sensors, microcomputer, a wireless data link, and battery. It measures the differential pressure between the total pressures captured by two total-pressure probes at each rotor angle, instead of using static pressure probes. Thus, the airspeed of the fuselage can be evaluated from the low speed. Flight tests were conducted employing a reference ultrasonic two-dimensional airspeed sensor for comparison. The results demonstrated that the magnitude error of the airspeed is less than 2 m/s for low-airspeed flights (<∼\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$<\\sim$$\\end{document}23 m/s) when utilizing Pitot-type probes. The error in wind angle approximated 30∘\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^\\circ$$\\end{document}, and the delay was less than or equal to that observed with a global navigation satellite system sensor.

Three-Dimensional Analytical Modeling of Rotational Eddy Current Speed Sensor

Three-Dimensional Analytical Modeling of Rotational Eddy Current Speed Sensor

Centralized load decoupling of a rotational multi-axis force sensor for measuring wheel-terrain interaction forces

For ensuring the safe mobility of off-road wheeled mobile robots (WMRs), the rotational multi-axis force sensor (RMFS) plays an important role in measuring the wheel-terrain interaction forces. However, the existing decoupling models cannot fully describe the coupling process of the RMFS when it is subjected to centralized loads, which is a common condition for off-road WMRs. A corrected decoupling model is proposed by taking elastic strains as the intermediate variable such that the coupling errors caused by centralized loads can be avoided. The proposed decoupling model replaces the original rotation matrix with a corrected matrix whose elements are odd harmonic functions. The calibration experiments indicate that the corrected model can reduce the variance of calibration error rate from 1.95% to 0.054% compared with another representative machine learning-based decoupling model. A set of simulation and physical tests also demonstrate that the decoupling model have good repeatability, accuracy and anti-vibration capability.

Rotation sensing using tractor atom interferometry

We investigate the possible realization of an ultracold-atom rotation sensor that is based on recently proposed tractor atom interferometry (TAI). An experimental design that includes the generation of a Laguerre–Gaussian-beam-based “pinwheel” optical lattice and multi-loop interferometric cycles is discussed. Numerical simulations of the proposed system demonstrate TAI rotation sensitivity comparable to that of contemporary matter-wave interferometers. We analyze a regime of TAI rotation sensors in which nonadiabatic effects may hinder the system's performance. We apply quantum optimal control to devise a methodology suitable to address this nonadiabaticity. Our studies are of interest for current efforts to realize compact and robust matter-wave rotation sensors, as well as for fundamental physics applications of TAI.

GINGERINO: a high sensitivity ring laser gyroscope for fundamental and quantum physics investigation

Ring Laser Gyroscopes, based on the Sagnac effect, are currently the most sensitive rotation sensors. GINGERINO, a RLG installed underground, shows a proved sensitivity that enters the few frad/s regime in about 2.5 days of integration time. On one hand, this sensitivity is well below the shot–noise–level as predicted applying to GINGERINO the so called independent beam model. On the other hand, it paves the way to the use of RLG in fundamental and quantum physics research. Indeed, high sensitivity rotation measurement opens to test general relativity and alternative theory of gravity. Moreover, it make possible to study the interplay between quantum effects in the optical domain and non-inertial reference frames.

Speed Measurement of the Moving Targets Using the Stepping Equivalent Range-Gate Method.

In this paper, we proposed a stepping equivalent range-gate method (S-ERG method) to measure the speed and the distance of the moving target for range-gated imaging lidar. In this method, the speed is obtained by recording the time at which the moving target passes the front and back edges of the range gate, the distance information can also be obtained by the front and back edges of the range gate at the same time. To verify the feasibility of this method, a stationary target and a moving target with different speeds were measured by the S-ERG method. By using the S-ERG method, we not only obtained the distance information of the stationary target and the moving target at the front and back edges of the range gate, respectively, but also obtained the speed of the moving target. Compared to speeds measured by rotational displacement sensors, the speed measurement error of the S-ERG method is less than 5%, whether the target is far away or close to the range-gated lidar system, and this method is almost independent of the delay step time. The theoretical analysis and experimental results indicate range-gated imaging lidar using the S-ERG method has high practicality and wide applications.

Wind turbines as a metamaterial-like urban layer: an experimental investigation using a dense seismic array and complementary sensing technologies

The deflection and the control of the effects of the complex urban seismic wavefield on the built environment is a major challenge in earthquake engineering. The interactions between the soil and the structures and between the structures strongly modify the lateral variability of ground motion seen in connection to earthquake damage. Here we investigate the idea that flexural and compressional resonances of tall turbines in a wind farm strongly influence the propagation of the seismic wavefield. A large-scale geophysical experiment demonstrates that surface waves are strongly damped in several distinct frequency bands when interacting at the resonances of a set of wind turbines. The ground-anchored arrangement of these turbines produces unusual amplitude and phase patterns in the observed seismic wavefield, in the intensity ratio between stations inside and outside the wind farm and in surface wave polarization while there is no metamaterial-like complete extinction of the wavefield. This demonstration is done by setting up a dense grid of 400 geophones and another set of radial broadband stations outside the wind farm to study the properties of the seismic wavefield propagating through the wind farm. Additional geophysical equipment (e.g., an optical fiber, rotational and barometric sensors) was used to provide essential explanatory and complementary measurements. A numerical model of the turbine also confirms the mechanical resonances that are responsible for the strong coupling between the wind turbines and the seismic wavefield observed in certain frequency ranges of engineering interest.

Non-hermiticity in spintronics: oscillation death in coupled spintronic nano-oscillators through emerging exceptional points

The emergence of exceptional points (EPs) in the parameter space of a non-hermitian (2D) eigenvalue problem has long been interest in mathematical physics, however, only in the last decade entered the scope of experiments. In coupled systems, EPs give rise to unique physical phenomena, and enable the development of highly sensitive sensors. Here, we demonstrate at room temperature the emergence of EPs in coupled spintronic nanoscale oscillators and exploit the system’s non-hermiticity. We observe amplitude death of self-oscillations and other complex dynamics, and develop a linearized non-hermitian model of the coupled spintronic system, which describes the main experimental features. The room temperature operation, and CMOS compatibility of our spintronic nanoscale oscillators means that they are ready to be employed in a variety of applications, such as field, current or rotation sensors, radiofrequeny and wireless devices, and in dedicated neuromorphic computing hardware. Furthermore, their unique and versatile properties, notably their large nonlinear behavior, open up unprecedented perspectives in experiments as well as in theory on the physics of exceptional points expanding to strongly nonlinear systems.

Obtaining moments of inertia using rotation sensor and filming with cellphone

Neste trabalho determinou-se o momento de inércia de uma haste retangular fina e um cilindro oco apartir de diferentes métodos. No primeiro método utilizou-se as dimensões dos objetos para inseri-los em equações teóricas e assim calcular os momentos de inércia. No segundo método utilizou-se as leis da dinâmica de rotação e translação, juntamente com conceitos de energia, para se obter equações que envolvem parâmetros físicos mensuráveis, permitindo de forma indireta o cálculo do momento de inércia. Neste caso foram realizados três experimentos distintos. No primeiro experimento utilizou-se um sensor de rotação e nos demais filmagens com aparelho celular. Todas as medidas indiretas resultaram em valores muito próximos e com diferenças percentuais ≈ 10% relativa ao valor calculado a partir das dimensões dos objetos.

Modified Frequency-Bessel Transform Method for Dispersion Imaging of Surface Wave from Six-Component Ambient Noise Recordings

Surface wave analysis methods based on ambient noise have attracted considerable attention within the geophysical and civil engineering communities, particularly in light of the limitations associated with traditional seismic surveys in densely populated urban areas. Conventionally, translational seismic sensors have been employed for the observation of ambient noise. Nevertheless, recent advancements in rotational sensor technology have facilitated the direct measurement of ground motion induced by seismic waves in a rotational manner. Through the integration of these rotational sensors with traditional inertial seismometers, a novel six-component seismic sensor has been developed. This innovative sensor enables the local observation of six degrees of freedom pertaining to ground motion, encompassing three orthogonal components of translational motion and three orthogonal components of rotational motion. In order to demonstrate the seismological significance of rotational ground-motion data, we applied the modified frequency-Bessel transform method (MFJ) to six-component ambient noise recordings for surface wave analysis. To underscore the practical utility of the MFJ method, a real-world case study is presented, illustrating its effectiveness in quantifying Rayleigh and Love wave dispersion from six-component ambient noise recordings.

Mechanical spectroscopy to determine the torsion modulus from hollow glass microspheres fillers in unsaturated polyester resin

This work presents an alternative to studying and determining the torsion modulus, G, in composites. For this purpose, a measuring system used a rotational motion sensor coupled to a torsion pendulum. The determination of the angular position as a function of time and an equation derived from studies of mechanical spectroscopy, allowed to determine the value of G, so experiments focused on samples of different quantities of hollow glass microspheres (HGMs) in unsaturated polyester resins. The G results show that the addition of HGMs (16.67 %W) reduces the value of torsion modulus by 31% when compared to the unsaturated resin (100 %W). On the other hand, considering the same two samples, there is a material density reduction of approximately 43% with the addition of HGMs, which makes these materials lighter, and of great practical interest. The relationship between G and material density shows that it is possible to change the amount of HGMs for optimal torsion resistance. The advantage of this technique, compared to other dynamic methods, is that it is not necessary to know the Poisson’s ratio of the material.

Fiber optic sensor embedded in robotic systems for 3-D orientation assessment using polymer fiber

The present work is considered to installed sensor system to the robotics system. The structure of 3-D rotational sensor is based on polymer fiber, where two fibers are twisted to couple the light. Twisted fibers are kept in a bending shape after twisting and installed on the robot where three scenarios are carried out. The bending radius variation leads to the bending loss in the first fiber, and the loss is being coupled in the second fiber. Robot's orientation causes the change in the macro-bend radius of the sensor. Our proposed sensor analyzes the robot's orientation where the robot is moved in the full rotational cycle from 0° to 360° in both clock and anti-clockwise rotation directions. Furthermore, the robot is also rotated at different speeds to analyze the dynamic response and also analyzed for simultaneous response of roll, pitch, and yaw's orientation. The results indicate that the proposed sensor of present work is a timely response with the robot moments. The simple structure and flexible 3-D rotational sensor structure pave to easily integrate into the robotics system.

A Laser Triangulation Displacement Sensor Based on a Cylindrical Annular Reflector

The ellipticity of the spot caused by laser jitter has a significant effect on the measurement accuracy of the traditional laser triangulation method. In order to overcome the influence of laser characteristics on measurement and improve the accuracy of displacement measurement, this paper proposes a measurement model for a laser displacement sensor based on a cylindrical annular reflector. A physical prototype is designed through parameter optimization using NSGA-II, and a two-step detection algorithm is proposed for the imaging ring of the prototype. The algorithm performs contour thinning after rough positioning of the imaging annular ring, and then performs precise detection. Through physical experiments, it is verified that the repeatability error of this method can reach below 0.02%, and the accuracy is significantly improved compared to traditional laser triangulation displacement sensors. Meanwhile, the measurement results of displacement show linearity. The optical path design of this sensor is simpler than the previously proposed rotational symmetrical laser triangulation displacement sensor, which has good application prospects.

Viability of rotation sensing using phonon interferometry in Bose-Einstein condensates

We demonstrate the use of a ring-shaped Bose-Einstein condensate as a rotation sensor by measuring the interference between two counter-propagating phonon modes imprinted azimuthally around the ring. We observe rapid decay of the excitations, quantified by quality factors of at most Q ≈ 27. We numerically model our experiment using the c-field methodology, allowing us to estimate the parameters that maximise the performance of our sensor. We explore the damping mechanisms underlying the observed phonon decay, and identify two distinct Landau scattering processes that each dominate at different driving amplitudes and temperatures. Our simulations reveal that Q is limited by strong damping of phonons even in the zero temperature limit. We perform an experimental proof-of-principle rotation measurement using persistent currents imprinted around the ring. We demonstrate a rotation sensitivity of up to \Delta \Omega ≈ 0.3 rad s^{-1}ΔΩ≈0.3rads−1 from a single image, with a theoretically achievable value of \Delta \Omega ≈ 0.04 rad s^{-1}ΔΩ≈0.04rads−1 in the atomic shot-noise limit. This is a significant improvement over the shot-noise-limited \Delta \Omega ≈ 1 rad s^{-1}ΔΩ≈1rads−1 sensitivity obtained by Marti et al. [Phys. Rev. A 91, 013602 (2015)] for a similar setup.

Rotation Sensing of a Trapped Nanoparticle Assisted by Magnetic Field Gradient

Rotation Sensing of a Trapped Nanoparticle Assisted by Magnetic Field Gradient

Rotating speed measurement using an optimized eddy current sensor

This paper presents the rotating speed measurement of solid iron hollow shafts using the optimum design of a rotational eddy current sensor. The rotating speed measurements are performed using the optimized sensor up to ±3000 rpm to evaluate sensitivity enhancement and linearity performance. The sensor is optimized for a shorter axial length and higher sensitivity with a new configuration of the coils. An aluminum shell on a solid shaft is used, which helps to improve the sensitivity and the susceptibility of the sensor to the material properties of solid iron. A 2D analytical method and a 3D time stepping finite element method are considered for the theoretical analysis of the sensor and for an assessment of the effect of this optimization on the performance. The performance of the sensor was verified by measurements. The evaluation of the speed sensor for higher speeds up to ±30,000 rpm is performed using the 2D analytical method.

A vacuum-compatible cylindrical inertial rotation sensor with picoradian sensitivity.

We describe an inertial rotation sensor with a 30-cm cylindrical proof-mass suspended from a pair of 14μm thick BeCu flexures. The angle between the proof-mass and support structure is measured with a pair of homodyne interferometers, which achieve a noise level of ∼5prad/Hz. The sensor is entirely made of vacuum compatible materials, and the center of mass can be adjusted remotely.

Development of the helicopter turboshafted engine regulator

The subject of research was the development of the RDC-450M-117V – the TV3-117VMA-SBM1V digital engine regulator – based on the RDC-450M previously created at the enterprise for the AI-450M engine, considering differences in engine characteristics and exploitation conditions. The work purpose was to develop RDC-450M-117V based on information about aircraft engine characteristics, including refinement of its mathematical model based on experimental data, taking into account the exploitation condition difference. The tasks faced by the developers were to determine the optimal regulator structure in view of exploitation conditions, refine the mathematical model of the engine, and study the characteristics of the pump-regulator, to select the optimal processing form for the signal of rotation sensors for torque measurement. The methods that were applied were experimental engine and pump-regulator characteristics study on the stands of JSC "Element", JSC "Motor Sich", and on pump-regulator manufacturer’s stands; processing of experimental data using numerical simulation with subsequent statistical analysis. The rotation sensors signals experimental data (waveforms) were studied using a quantitative analysis method. The results. Design and software documentation was developed considering the requirements of international standards DO-254 and DO-178C, and a prototype of the regulator new modification was made. The engine mathematical model was refined, on the basis of which the stand-imitator of aircraft engines was finalized for a new type of engine. An adaptive algorithm for controlling the pump-regulator was developed, which made it possible to ensure stable maintenance of fuel consumption, despite the unstable operation of the pump-regulator. Using a quantitative analysis of the torque sensor signal waveforms, characteristic points were found that ensure the choice of the optimal level of comparison (measurement). The pilot regulator prototype passed tests including electromagnetic compatibility and lightning resistance in specialized laboratories in Ukraine. The regulator was tested as part of the engine at the Motor Sich JSC stands and as part of a helicopter at the foreign customer site, including the first demonstration flight. The scientific novelty of the obtained results are: the clarified engine TV3-117VMA-SBM1V mathematical model was formed and implemented in a stand-imitator; the adaptive algorithm for controlling the pump-regulator was formed and allowed to provide stable fuel consumption maintenance, despite the pump-regulator unstable operation; and the optimal processing form for the signal of rotation sensors for measuring torque was selected. Practical significance. A new engine regulator was developed and tested, and it provided the first helicopter demonstration flight.

A New Paradigm for Structural Characterization, including Rotational Measurements at a Single Site

ABSTRACT In this article, we demonstrate that a single station can be used to measure the dynamic properties of a structure. The station includes a collocated accelerometer and rotational sensor, hence, can record both three-component translation and three-component rotation and is referred to as the 6C-station within this study. The key advantage of this approach is to provide a fast and simple path to a comprehensive structural health monitoring characterization that is comparable to the use of a traditional approach using a horizontal array of three-component accelerometers. The deployment of newly developed high-quality rotational sensors allows the direct measurement of structural rotations, facilitating the extraction of structural mode shapes. In this work, we show how an established system identification tool, stochastic subspace identification, can be applied to the 6C-station data and characterize modal properties and structural response. Our results are verified and contrasted against standard horizontal and vertical array configurations. The Prime Tower, a high-rise structure in Zürich, serves as a case study. A structural characterization of this building is presented for the first time. We show that a 6C-station is capable of defining the frequencies of this stiff high-rise building with a fidelity that is on par with a five-sensor horizontal array. The mode shapes of the roof can be precisely determined with a confidence margin that is comparable to conventional sensing array solutions. However, the effectiveness of using only a 6C-station is determined by the noise level of the sensors—in particular, the rotational seismometer needs to be of high quality. The results indicate that, owing to the collocation measurement of translation and rotation, a 6C-station can deliver a comprehensive structural monitoring solution with minimum time, effort, and footprint.

DESIGN OF GENSET MONITORING &amp; RECORDING EQUIPMENT WITH THE CONCEPT OF INTERNET OF THINGS (IOT) BASED ON ARDUINO UNO

Generators are widely used in offices, hospitals and companies that require a 24-hour electricity supply. Generators are often used to replace the main power supply from PLN in the event of a power outage. The purpose of this thesis is to make it easier for technicians to monitor the condition of the output from the generator, namely current, voltage, and rotational speed (RPM) with a monitoring and recording system that can work remotely. With the existence of a system of monitoring and recording remotely via a personal computer that can streamline the technician's time. Arduino uno as a data processing center that is integrated with the database. The monitoring and recording system on the generator is activated by connecting Wifi then this arduino gets input from the current, voltage and rotational speed sensors (RPM) the data will be processed with the arduino uno according to the data created on the system. This system is also displayed using Bylnk via a personal computer.