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This paper presents a digital MEMS gyroscope with 40${}^{\circ }$/h instability variation in −40${}^{\circ }$C to 85${}^{\circ }$C, performing 5${}^{\circ }$/h instability variation at normal temperature and 0.01% nonlinearity in the range of ±400${}^{\circ }$/s. This stability was achieved by using temperature compensation for the zero-output value changed after the temperature signal. As the resonant frequency of the mechanical structure varied according to the temperature linearly, a frequency calculator was adopted to detect the temperature of the mechanical structure. And the resolution of the frequency could be up to 0.01 Hz with a 1 MHz clock frequency used, obtaining a 10 Hz bandwidth. The driving mode used a PI controller to control a VGA to maintain at a fixed effective value of the driving signal. The sensing mode contained a low noise C/V convertor and a switch demodulation, which could give the angular velocity signal to the A/D convertor. Then the output data of A/D will be compensated in the digital domain. Finally, the digital output of the gyroscope will be available through a normal SPI serial port. The whole circuit was realized on one chip with an active circuit area of 3.5 mm × 5.2 mm fabricated in a 0.35 $\mu$m CMOS technology. And the MEMS structure and circuit are packaged in a 2.5 cm × 2.5 cm × 2.5 cm aluminum mold. The digital output of the gyroscope earned a noise floor of 0.0024${}^{\circ }$/s.

The all temperature range stability is the most important technology of MEMS angular velocity sensor according to the principle of capacity detecting. The correlation between driven force and zero-point of sensor is summarized according to the temperature characteristic of the air-damping and resonant frequency of sensor header. A constant trans-conductance high-linearity amplifier is designed to realize the low phase-drift and low amplitude-drift interface circuit at all-temperature range. The chip is fabricated in a standard 0.5 $\mu \mathrm{\text{m}}$ CMOS process. Compensation achieved by driven force to zero-point drift caused by the stiffness of physical construction and air-damping is adopted. Moreover, the driven force can be obtained from the drive-circuit to avoid the complex sampling. The test result shows that the zero-point drift is lower than 30${}^{\circ }$/h (1-sigma) at the temperature range from −40${}^{\circ }$C to 60${}^{\circ }$C after three-order compensation made by driven force.

In this research, the angular rotation speed in a passive photonic gyroscope based on the combination of side nanoring resonators and compensating waveguides has been analyzed by creating nonlinear effects in the control factors of the rings using the Sagnac effect. This structure consists of a central waveguide, two identical square resonators, and an almost U-shaped waveguide. The U-shaped waveguide causes coupling between the two resonators in a counterclockwise (CCW) mode. In this structure, a phase shift has been created in the output from the interference of two clockwise (CW) and CCW waves inside the resonators, and according to this phase shift and the central wavelength, the angular rotation speed has been estimated. In the proposed design of the gyroscope, by managing the nonlinear effects in the radius and refractive index (RI) of the coupling and inner rods, we have been able to control the changes in power, phase, and wavelength of the output from the device. With the increase in the intensity of power, the output power has an increasing slope at first, and at the point of creating a nonlinear effect in the sensor, the output power slope decreases. Also, this nonlinear effect directly affects the output phase of the structure. The maximum angular rotation speed in this gyroscope was $6.68\times 10^8{}^{\circ }$/s. By changing the RI of the inner rods from 3.2 to 3.7, the maximum output-to-input power ratio changes from 0.38 W/$\mu$m² to 0.75 W/$\mu$m². By changing the radius of the coupling rods from 93 nm to 97 nm, the maximum power ratio decreases from 0.78 W/$\mu$m² to 0.55 W/$\mu$m². The field distribution profile and photonic bandgap in this gyroscope have been analyzed using the finite-difference time-domain (FDTD) and plane-wave expansion (PWE) methods, respectively. Also, the gyroscope has a footprint of 163.5 $\mu$m².

Gyroscopes IN General Relativity (GINGER) is a proposal of an Earth-base experiment to measure the Lense–Thirring effect. GINGER uses an array of ring lasers, which are the most sensitive inertial sensors to measure the rotation rate of the Earth. GINGER is based on a three-dimensional array of large size ring lasers, able to measure the de Sitter and Lense–Thirring effects. The instrument will be located in the INFN Gran Sasso underground laboratory, in Italy. We describe preliminary developments and measurements. Earlier prototypes based in Italy, GP2, GINGERino, and G-LAS are also described and their preliminary results reported.

In order to ascertain the utility of a 250 Hz NSD Powerball^® gyroscope in increasing the maximum grip force and muscular endurance of the forearm, ten adults without pathology in their upper limbs exercised one forearm with the device during a period of one month. We evaluated grip strength and forearm muscle endurance with a Jamar dynamometer both at the end of the month as well as after a resting period of one month. There was a tendency (not statistically significant p = 0.054), for the volunteers to increase their maximum grip strength. There was also highly significant increase in muscle endurance (p = 0.00001), a gain that remained slightly unchanged after the rest. Because the gyroscope generates random multidirectional forces to the forearm, the reactive muscle contraction is likely to stimulate more efficient neuromuscular contro of the wrist, a conclusion which our work appears to validate. The use of Powerball^® in forearm proprioception deficient patients is, therefore, justified.

Gait symmetry has been considered as one of the primary indicators in gait analysis. A symmetrical gait offers several benefits. Among them is a stable and adaptive gait. With wide adoption of wireless inertial sensors i.e., the gyroscope in clinical and rehabilitation settings, this work aimed to investigate the application of symmetry index (SI), symmetry ratio (SR) and normalised symmetry index (SInorm) in defining gait symmetry using measurement collected from wireless gyroscope network. Thigh and shank angular rates during mid-swing, heel-strike and toe-off are used to determine SI, SR and SInorm. In this study, participants were not only instructed to walk naturally on the ground and on a treadmill, but were also requested to walk with restricted knee movement on the ground and on a treadmill to emulate asymmetrical gait. This study demonstrated that the gyroscope can be used to determine gait symmetry. It also shows that SI and SR are not the right indicators to examine gait symmetry using gyroscope data. SI can exceed more than 1,000% at several instances. SR exhibits similar behavior too i.e., it can be as high as 1,000. SInorm performs better in both overground walking and treadmill walking and there are significant difference between symmetrical and asymmetrical gait (p < 0.01).

The patellar tendon reflex response provides fundamental means of assessing a subject’s neurological health. Dysfunction regarding the characteristics of the reflex response may warrant the escalation to more advanced diagnostic techniques. Current strategies involve the manual elicitation of the patellar tendon reflex by a highly skilled clinician with subsequent interpretation according to an ordinal scale. The reliability of the ordinal scale approach is a topic of contention. Highly skilled clinicians have been in disagreement regarding even the observation of asymmetric reflex pairs. An alternative strategy incorporated the ubiquitous smartphone with a software application to function as a wireless gyroscope platform for quantifying the reflex response. Each gyroscope signal recording of the reflex response can be conveyed wirelessly through Internet connectivity as an email attachment. The reflex response is evoked through a potential energy impact pendulum that enables prescribed targeting and potential energy level. The smartphone functioning as a wireless gyroscope platform reveals an observationally representative gyroscope signal of the reflex response. Three notably distinguishable attributes of the reflex response are incorporated into a feature set for machine learning: maximum angular rate of rotation, minimum angular rate of rotation, and time disparity between maximum and minimum angular rate of rotation. Four machine learning platforms such as the J48 decision tree, K-nearest neighbors, logistic regression, and support vector machine, were applied to the patellar tendon reflex response feature set incorporating a hemiplegic patellar tendon reflex pair. The J48 decision tree attained 98% classification accuracy, and the K-nearest neighbors, logistic regression, and support vector machine achieved perfect classification accuracy for distinguishing between a hemiplegic affected leg and unaffected leg patellar tendon reflex pair. The research findings reveal the potential of machine learning for enabling advanced diagnostic acuity respective of the gyroscope signal of the patellar tendon reflex response.

Monitoring human gait is essential to quantify gait issues associated with fall-prone individuals as well as other gait-related movement disorders. Being portable and cost-effective, ambulatory gait analysis using inertial sensors is considered a promising alternative to traditional laboratory-based approach. The current study aimed to provide a method for predicting the spatio-temporal gait parameters using the wrist-worn inertial sensors. Eight young adults were involved in a laboratory study. Optical motion analysis system and force-plates were used for the assessment of baseline gait parameters. Spatio-temporal features of an Inertial Measurement Unit (IMU) on the wrist were analyzed. Multi-variate correlation analyses were performed to develop gait parameter prediction models. The results indicated that gait stride time was strongly correlated with peak-to-peak duration of wrist gyroscope signal in the anterio-posterior direction. Meanwhile, gait stride length was successfully predicted using a combination model of peak resultant wrist acceleration and peak sagittal wrist angle. In conclusion, current study provided the evidence that the wrist-worn inertial sensors are capable of estimating spatio-temporal gait parameters. This finding paves the foundation for developing a wrist-worn gait monitor with high user compliance.

Although tremor is one of the most common movement disorders, there are few effective tremor-suppressing options available to patients. Gyrostabilization is a potential option, but we do not currently know how to optimize gyrostabilization for tremor suppression. To address this gap, we present a systematic investigation of how gyrostabilizer parameters affect tremor suppression in a single degree of freedom (DOF). A simple model with a single DOF at the wrist and a gyroscope mounted on the back of the hand was used to focus on the most basic effects. We simulated the frequency response of the system (hand + gyroscope) to a tremorogenic input torque at the wrist. Varying system parameters one at a time, we determined the effect of individual parameters on the system’s frequency response. To minimize the bandwidth without adding significant inertia, the inertia and spin speed of the flywheel should be as high as design constraints allow, whereas the distance from the wrist joint axis to the gyroscope and the precession stiffness and damping should be kept as low as possible. The results demonstrate the potential of gyroscopic tremor suppression and can serve as foundation for further investigations of gyroscopic tremor suppression in the upper limb.

The structural principle of a novel silicon micromachined gyroscope, driven by the rotating carrier's angular velocity, is presented in this paper. The authors construct the mathematical module of the micromachined gyroscope and the dynamics parameters of the micromachined gyroscope are also analyzed and calculated. The signal detecting circuit of the micromachined gyroscope is described. The micromachined gyroscope uses capacitive variation to sense angular velocity and such operation principle is demonstrated in the paper. Then, the signal processing circuit of the micromachined gyroscope is analyzed in detail. Finally, the finite element analysis tool — ANSYS software is used to analyze the oscillation module and frequency response of the micromachined gyroscope. The theoretical research and computer imitation have certified that the structural principle of the silicon micromachined gyroscope driven by rotating carrier's angular velocity is correct.

Friction is a complicated phenomenon that plays a central role in a wide variety of physical systems. An accurate modeling of the friction forces is required in the model-based design approach, especially when the efficiency optimization and system controllability are the core of the design. In this work, a gyroscopic unit is considered as case study: the flywheel rotation is affected by different friction sources that needs to be compensated by the flywheel motor. An accurate modeling of the dissipations can be useful for the system efficiency optimization. According to the inertial sea wave energy converter (ISWEC) gyroscope layout, friction forces are modeled and their dependency with respect to the various physical quantities involved is examined. The mathematical model of friction forces is validated against the experimental data acquired during the laboratory testing of the ISWEC gyroscope. Moreover, in the wave energy field, it is common to work with scale prototypes during the full-scale device development. For this reason, the scale effect on dissipations has been correlated based on the Froude scaling law, which is commonly used for wave energy converter scaling. Moreover, a mixed Froude–Reynolds scaling law is taken into account, in order to maintain the scale of the fluid-dynamic losses due to flywheel rotation. The analytical study is accompanied by a series of simulations based on the properties of the ISWEC full-scale gyroscope.

Autism is one of the developmental disorders which make major behavioral and communication changes in the individual and induce a major drawback in the walking pattern. The main aim of this study is to analyze and compare the stride patterns of an autistic patient and a healthy individual. With the help of the proposed device, the yaw, pitch and roll of the limbs can be easily measured and analyzed. These parameters will identify the lacking movement patterns and help the physiotherapists in improving the walking pattern of the autistic patients by adopting the correct approach of remedial actions/treatment. It can also be used by the people who have undergone hip replacements or knee replacements and have an abnormal gait pattern. This device is a simple accumulation of sensors and memory storage unit. Two gyroscope sensors have been used, one each for the knee and the ankle. These sensors are strapped onto the knee and ankle with the help of free-sized elastic bands. The data received by the sensors are stored in the storage device automatically and are evaluated in a specially designed Web application. However, the raw data from the gyroscope sensors have not been used directly and various filters have been used to remove the errors. The results have been compared between an autistic patient and a normal healthy subject and showed a higher degree of angle difference for the autistic patient than the normal individual.

Since Lakoff and Johnson (1980) claimed that metaphor is a matter of thought and action, the metaphor has been not only the rhetoric of literature but also an essential conceptual tool for people to understand and remember the physical world. In this research, we concretize the process of mind transformation of a metaphor through augmented reality (AR) technology. The AR interactive system that we create from the concept of Max Black’s interaction view of metaphor can display the interaction phenomenon of metaphor from two different domains (rabbit or duck). We use the character of the rabbit–duck illusion as an example of a 3-D virtual model demonstration. This ambiguous 3-D character can be transformed from rabbit to duck with morphing technology. In this system, people can choose their preferences for looking at either rabbit, duck, or rabbit–duck blending. We focus on the morphing visual effect of AR as a metaphor tool and display the blending concept of the pictorial metaphor when the morphing is animated. The AR interactive system combines with an assembly of the gyroscopic motion controller connected to camera movements and morphing parameters. We attempt to prove that changing the camera view can represent the concrete expression of the abstract concept of visual metaphor in the AR system. For example, moving the camera is equivalent to the changing of thoughts and actions of people, and the 3-D morphing is equivalent to a mapping of the hybrid metaphor that people expect to see.

After assessments, this AR system can track the preferences of users by collecting the data of camera raycasting points, and we believe that the system can benefit the developments of museum education and guidebooks in terms of explaining the visual semiotics of artworks.

We present the evaluation of the performances of our cold atom gyroscope. The gyroscope is based on two cold Cesium atom sources, which are manipulated thanks to Raman transitions. We show that the short term sensitivity is limited by the quantum projection noise and the long term sensitivity by wave front distortion of the Raman lasers. A study of the bias and scaling factor completes the characterization of the sensor.

This paper explores the properties of a precessing rotor or a coupled system of precessing rotors (gyroscopes), where a special chaotic behavior in the precession angle can be found if the change of rotor angular velocity is linearly coupled by (an)holonomy to the precession angular velocity and angle. The linear coupling provides for rolling cone paths and allows spinning up and controlling the rotor simply by forcing precession at special quantum magic precession angles. The geometric phase induced by the curved path of the rotor or external curvature and part of the coupling increases with precession angle. This leads to bifurcations in coupling strength resulting in chaotic precession. As an alternative to the SO(3) matrix or quaternion representation the treatment of the three coupled rotations is here based on Euler's dynamical equations. First, the classical Magic Angle Precession (MAP) dynamics is realized by a geometric or mechanical condition (type I, transcendental solutions), where it can be experimentally demonstrated how MAP can "slave" angular degrees of freedom allowing the external control of high-frequent spin by slow oscillations. MAP is found in a commercial fitness device and is conceptually approached via Chua's electric circuit. Second, the quantum-gravitational MAP (type II, rational solutions) with discrete precession angles is analyzed on a deeper level requiring intrinsic curvature/relativistic effects adjusting holonomy to quantum numbers. Third, a macroscopic network of MAP elements is presented as a discrete-time recurrent neural network synchronizing to one common MAP I/II dynamics under special pairing and symmetry conditions (type III). In all three cases MAP can be treated as a time-discrete chaotic system with singularities given by the cosine map with several possible links to interesting applications on all scales.

The paper comparative researched the dry air, nitrogen and helium and other effects of three kinds of commonly used sensitive gases on the sensitivity of the piezoelectric fluidic angular rate sensor. By using the finite element method, calculated the flow field in sensing element of piezoelectric fluidic angular rate sensor under the effect of the input angular velocity of 20°/S The results are as follow: (1) Changing the type of sensitive working gas in the piezoelectric fluidic angular rate sensor sensitive element, the distribution of flow field also changes. (2) The input angular velocity is 20°/S, the airflow velocity difference between two heat resistance wire r1 and r2 namely ΔVN2> ΔVAIR> ΔVH. (3) The sensitivity coefficient, namely KN2> KAIR> KHe, among them, KN2 is 1.05 times of KAIR, KHe, is 0.21% of KAIR. (4) Nitrogen is corresponding to the highest sensitivity, the thermal resistance wires antioxidant, stability is better, but the cost is high; sensitivity of dry air secondly, the thermal resistance wires easily oxidized, poor stability; helium corresponding to the minimum sensitivity, thermal resistance wire is not easy to be oxidized, the best stability. This paper explained the mechanism of sensitive working gas influence on sensitivity of piezoelectric fluidic angular rate sensor, in order to improve the practicability of the piezoelectric fluidic angular rate sensor, meet different engineering needs to open up a new way.

Based on the research on optical fiber gyro realize robot precision localization system, the composition of the robot positioning system were introduced first, and then introduced the basic principle of optical fiber gyro and performance indicators. Finally, the parameter was tested of fiber optic gyroscope. Results show that the fiber optic gyro parameters satisfy the requirement of the robot positioning.