Attitude Stabilization Control Research Articles

Neural Ensemble Dynamics in Trunk and Hindlimb Sensorimotor Cortex Encode for the Control of Postural Stability

Neural Ensemble Dynamics in Trunk and Hindlimb Sensorimotor Cortex Encode for the Control of Postural Stability

Caffeine Enhances the Balance System and Postural Balance in Short Time in Healthy Individuals.

Objective:This study aimed to explore the effects of caffeine on balance function by determining the extent to which caffeine consumption affects postural sway and balance control in healthy individuals.Methods:Thirty healthy participants aged 20–35 years without any vestibular disorder were enrolled in this study. The participants were randomly divided into two groups, and those in Group 1 were given two cups of regular coffee (300–350 mg) while those in Group 2 were given two cups of decaffeinated coffee. The sensory organization test, the head shake sensory organization test, the limits of stability test, and the adaptation test were performed on all participants before and after coffee intake using computerized dynamic posturography.Results:The sensory organization test composite scores (p=0.001) and the head shake condition 5 (C5) equilibrium scores (p=0.001) of the participants in Group 1 showed a statistically significant increase after coffee intake while the composite scores (p=0.001) and the head shake condition (C5) equilibrium scores (p=0.001) of those in Group 2 showed a statistically significant decrease. There was a statistically significant difference between the two groups in the equilibrium scores in the pitch plane (p=0.001), the yaw plane (p=0.001), and the roll plane (p=0.001) of C5 after coffee intake.Conclusion:Consumption of an appropriate dose of caffeine may enhance body position, postural stability, and voluntary motor control ability. The combined use of the sensory organization test, the head shake sensory organization test, the adaptation test, and the limits of stability test in evaluating the balance mechanism in individuals with normal vestibular findings provides detailed information about postural sway.

The effect of latin dance on dynamic balance

BackgroundFigures and movements in Latin dance are effectively used to provide posture stabilization and balance control. A Computerized Dynamic Posturography can be used to complete a functional evaluation of postural control and stability in static and dynamic conditions, mediated by the interaction between the visual, vestibular, and somatosensory systems. Research QuestionAccording to the results of Computerized Dynamic Posturography, do dancers have better postural control and stability when compared to non-dancers, and can dance activity be recommended for vestibular rehabilitation? Material and methodsOur study included 26 professional Latin dancers and 26 non-dancers as a control group whoboth had no problems with their hearing or balance. Pure-tone audiometry and Computerized Dynamic Posturography tests were applied to the participants. The test results for the professional dancers and the control group were compared and evaluated. In statistical analysis, the Mann-Whitney U and Independent Samples T tests were used. A value of p < 0.05 was accepted for significance. ResultsAccording to the results of the Computerized Dynamic Posturography, the dancers generally performed better than the control group. While statistically significant and better performances were observed in dancers in terms of the composite balance, visual and vestibular scores within the scope of the Sensory Organization Test (p < 0.05), no statistically significant difference was found for somatosensory and preference scores (p > 0.05). Also, significant differences were obtained between the two groups in some subtests of Adaptation, Unilateral Stance and Limits of Stability assessment (p < 0.05). No significant difference was observed in Rhythmic Weight Shift results (p > 0.05). ImportanceThe results of thisresearch demonstrate that balance and posture improve through dance. Therefore, adding appropriate dance activities to vestibular rehabilitation programmes might be helpful.

Impulsive control for attitude stabilization in the presence of unknown bounded external disturbances

AbstractIn this article, impulsive control is firstly considered for the quaternion‐based attitude stabilization of a rigid spacecraft. Inspired by the robustness of sliding mode control, a new concept of impulsive‐sliding mode is proposed to design robust impulsive controller for attitude stabilization. It illustrates that the designed impulsive controller possesses simple structure and robustness with respect to external disturbances. In order to achieve the relaxation of continuous measurement, we utilize periodic state measurement that is more economical and practical than the continuous one. Namely, we can achieve attitude stabilization and resource economization by adopting only discrete state measurement and discrete control input. More interestingly, our results can overcome the difficulty that the upper bound of disturbances is unknown, which is often required to design adaptive controller to handle in previous results. Moreover, we prove that the phenomenon can be excluded under the proposed periodic event‐triggering strategy and the interevent time has a uniform lower bound. An illustrative example is presented to show the feasibility of our results.

Attitude stability control of micro-nano satellite orbit maneuver based on bias momentum

In this paper, an attitude stability control strategy based on cold air micro propulsion microsatellite orbital maneuver is designed. Firstly, the influence of environmental disturbance moment, uncertainty of rotational moment of inertia and thrust eccentricity moment on the attitude stability of the micro-nano-satellite is considered, and the attitude dynamics model of the micro-nano-satellite based on biased momentum wheel and magnetic moment device is established. Then, the disturbance moments such as environmental disturbance moments, rotational inertia uncertainty and thrust eccentricity moments are analyzed. In order to suppress the influence of various internal and external disturbance factors on the stability of the micro-nano-satellite during the deorbiting process, a robust adaptive sliding mode variable structure controller is designed. The designed robust adaptive sliding mode controller is able to compensate for various disturbances adaptively. The robust adaptive sliding-mode variable structure controller is designed with a reasonable distribution of torque considering the characteristics of bias momentum wheel control and magnetic control. Finally, numerical simulations are performed, and the simulation results show that the system has good robustness.

Attitude stability control of UAV gyroscope based on neutral statistics for smart cities

Attitude stability control of UAV gyroscope based on neutral statistics for smart cities

High Accuracy Attitude Controlling of Vehicles for launching According to Deformation Reconstruction

To solve the problem that the curvature information of the large flexible rocket body affects the attitude controlling for rocket body, the present study proposes an attitude controlling approach by complying with reconstruction for deformation, which can realize the highly precise attitude controlling of the large flexible vehicle for launching. Firstly, the deformation parameters of the rocket were obtained by using the fiber grating sensing device. Then, the deformation information and attitude information were introduced into the increment-based dynamic inversing control loop at the same time, and the attitude controlling framework containing the deformation information of the rocket was established. Finally, the results achieved based on the simulation show that for flexible vehicles for launching with obvious vibration and deformation, this approach can compensate the faults attributed to elastic deformation and improve the accuracy and stability of attitude control.

Static and dynamic balance impairment and relationship with disease-related factors in patients with chronic obstructive pulmonary disease : Across-sectional study.

Disease and aging-related factors may predispose chronic obstructive pulmonary disease (COPD) patients to impaired balance, although the underlying determinants of impaired balance in COPD patients are still unknown. The purpose of this study was to identify the determinants of impaired balance in COPD patients. Also, we aimed to determine which balance measures (clinical or laboratory tests) are more indicative in determining balance impairment in these patients. This cross-sectional study recruited 24 patients with moderate to severe COPD and 24 age-matched healthy subjects. Participants were evaluated regarding demographic and clinical data, previous falls history, lower limb muscle strength, exercise capacity, physical activity and balance level. COPD patients exhibited significantly alonger test duration on timed up and go test, ahigher sway index on the postural stability and lower directional control score on the limit of stability of Biodex balance system (all, p < 0.001) compared to healthy controls, whereas there was no difference in Berg balance scale score between groups (p > 0.05). Balance impairment of the patient group was significantly associated with nonpulmonary conditions, such as physical activity level, exercise capacity, lower limb muscle strength, and with fall history. Also, COPD patients represented significantly lower physical activity level and exercise capacity, weaker lower limb muscle strength than healthy controls (all, p < 0.001). Patients with moderate to severe COPD exhibit apparently important reductions in balance control that is directly associated with nonpulmonary consequences and fall history. These results may be extremely important to fall prevention and to guide the development of interventions for this population.

Test-Retest Reliability of Low-Cost Posturography for Assessing Postural Stability Control Performance during Standing.

Postural stability control performance assessment is necessary in providing important information for individuals who are at risk of falling or who have balance impairment. Instrumented assessment is suggested as a valid and reliable test, but the cost and the difficulty of setup are significant limitations. The aim of this cross-sectional (test-retest reliability) study was to develop and determine the reliability of a low-cost posturography for assessing postural stability control performance during standing. The low-cost posturography was developed with four load cells and an acrylic platform. The center of pressure (COP) displacement and velocity were analyzed using written software. Test-retest reliability was performed with six different standing postural stability tests in twenty healthy volunteers on two different days. Intraclass correlation coefficient (ICC), standard error of measurement (SEM), coefficient of variation (CV), and Bland–Altman plot and limits of agreements (LOA) were used for analyses. The low-cost posturography was accurate (ICC = 0.99, p < 0.001; SEM = 0.003 cm) when compared to the true with calculated X and Y coordinates, with a moderate to excellent test-retest reliability for both COP displacement (ICCs ranged 0.62–0.91, p < 0.05; SEMs ranged 17.92–25.77%) and COP velocity (ICCs ranged 0.62–0.91, p < 0.05; SEMs ranged 18.09–27.69%) in all standing postural stability tests. Bland–Altman plots and LOAs suggested good agreement of tested parameters from the developed low-cost posturography between different days. In conclusion, the developed low-cost posturography had adequate reliability for assessing COP displacement and velocity during standing postural control stability performance tests.

Event-Triggered Policy to Spacecraft Attitude Stabilization With Actuator Output Nonlinearities

This brief investigates event-triggered control for spacecraft attitude stabilization under the influence of actuator output nonlinearities. Under a designed event-triggered policy, the influences of actuators' inherent nonlinearity and network quantized transmission are evaluated under a unified framework. Compared with the previous results, the influences of data transmission and actuators' inherent nonlinearities are uniformly described as the actuator output nonlinearities, and the event-triggered policy reduces the effects of constants commonly introduced into triggering conditions on the final state convergence regions and achieves Zeno-free triggering. Simulations verify theoretical results.

Correlation between Postural Stabilty and Functional Disabilty in Patients with Chronic Low Back Pain

Purpose: To investigate the relationship between static and dynamic postural stability and functionaldisability associated with chronic low back pain (CLBP).Methods: A total of 80 patients (age 44.64 ± 1.27 years) were recruited in this cross sectional studyusing convenience sampling. The One Leg Stand Test (OLST) was used to assess static balance witheyes open and eyes closed; Y Balance Test- Lower Quarter (YBT-LQ) was used to assess dynamicbalance in the anterior, posterolateral and posteromedial directions; and functional disability wasassessed using modified Oswestry Disability Index (mODI). Karl Pearson correlation coefficient wasused to estimate the relationship between the variables.Results and Conclusion: mODI was negatively correlated to OLST with eyes closed (r= -0.721); YBTLQcomposite score (r= -0.865); and reach distances in the posterolateral (r= -0.815) and posteromedial(r= -0.832) directions suggesting that control of postural stability was reduced with an increase indisability in patients with CLBP.

THE EFFECTIVENESS OF PROPRIOCEPTIVE NEUROMUSCULAR FACILITATION IN MECHANICAL NECK PAIN: A SYSTEMATIC REVIEW

Introduction: Neck pain is a health condition that has a high incidence rate and causes an inability to do daily activities and requires cost in handling it. People with neck pain could be associated with an alteration and deficit of the proprioception of the muscle and neck joint that play a significant role in joint position, postural stability, and motor control of the head and neck. Objective: The purpose of this systematic review is to find out the effectiveness of proprioceptive neuromuscular facilitation in mechanical neck pain. Method: The systematic review access to journal databases such as: PubMed Central (PMC) NCBI, Physiotherapy Evidence Database (PEDro), ProQuest, Google Scholar, MEDLINE, and the Cochrane Controlled Trials Register in the Cochrane Library. Results: The initial search in 6 databases found a total of 30 articles. Based on inclusion and exclusion criteria 4 articles were used in this systematic review. The application of the muscle energy techniques was applied ranging from 1 time to 8 weeks of intervention. From the 4 reviewed studies concluded that proprioceptive neuromuscular facilitation was effective in improving neck range of motion and function in mechanical neck pain. Conclusion: Based on the results of this systematic review it can be concluded that proprioceptive neuromuscular facilitation is effective in improving pain, pain threshold, range of motion, and functional performance in individual with neck pain. The appropriate articles are still limited to 4 studies, but have good to strong qualities. In addition, the application of intervention does not have the same standard.

Attitude control of flapping wing aircraft based on energy optimization and ESO

Aiming at the problem of insufficient endurance performance of flapping wing aircraft, a stable attitude control algorithm based on energy optimization and ESO (extended state observer) is designed, which effectively reduces the energy consumption in cruise phase. Firstly, the longitudinal dynamic model of flapping wing aircraft is established, and then the uncertain part of the system and various unknown external disturbances are taken as the total disturbance. ESO module is introduced to observe and track the total disturbance in real time. Therefore, the system is transformed into a series integral system through the total disturbance feedback, and then the energy optimal control law is designed on the base of the transformed system. The numerical simulation results show that, compared with the traditional PID control method, the designed energy optimal control method reduces the average energy consumption by 35.28%.

Neural network-based robust finite-time attitude stabilization for rigid spacecraft under angular velocity constraint

In this paper, the problem of attitude stabilization control of spacecraft under angular velocity constraint is investigated. A state-constrained finite-time attitude control scheme is designed by making full use of the model feature of the quaternion. Based on the homogeneous domination approach, the finite-time stability of the closed-loop system is proved. It proves that the angular velocity can be constrained within the limited range at any time. For the attitude loop dynamics subsystem with external disturbances, based on a radial basis function neural network, an integral terminal sliding mode controller is proposed. Finally, the validity and advantages of the proposed control scheme are demonstrated in the simulation section compared with the other two control methods.

Neural-networks and event-based fault-tolerant control for spacecraft attitude stabilization

This paper proposes a neural network and event-based fault-tolerant control scheme for spacecraft attitude stabilization in the presence of lumped disturbances, which consists of space disturbances, inertia uncertainties, and actuator faults. A neuro-adaptive estimator is employed to approximate the lumped disturbances, with the help of its powerful adaptive estimation capability of approximating any unknown smooth nonlinear function with arbitrary accuracy. The estimation is then utilized to formulate an integrated event-based dual-channel control scheme that can both guarantee the system's convergence and ensure the event triggering sequence possessing no-Zeno behavior simultaneously. The proposed control scheme provides a new and straightforward way for spacecraft attitude control to deal with lumped disturbances while requiring a low actuator updating frequency, thus saves on-board communication resources. Numerical simulations show the effectiveness of the algorithms.

Adaptive fuzzy backstepping control for attitude stabilization of flexible spacecraft with signal quantization and actuator faults

Adaptive fuzzy backstepping control for attitude stabilization of flexible spacecraft with signal quantization and actuator faults

Quadrotor UAV attitude stabilization using fuzzy robust control

In this paper, a robust controller for attitude stabilization of a small quadrotor helicopter is developed. The TS (Takagi-Sugeno) fuzzy model approach and the [Formula: see text] robust control are combined to produce the proposed algorithm. Besides, disturbances and parametric uncertainties are considered. First, the nonlinear model of the vehicle is linearized around several operating points to obtain the representation of a TS fuzzy model, which represents the nonlinearity of the system dynamics. Then, a robust fuzzy controller is synthesized which guarantees desired control performances. The given controller is designed using numerical tools such as linear matrix inequalities (LMI). Finally, simulation results and real-time experiments are presented to validate the performance of the proposed scheme to robustly stabilize the quadrotor dynamics at the desired reference.

Nonlinear Control for Attitude Stabilization of a Rigid Body Forced by Nonstationary Disturbances with Zero Mean Values

A rigid body forced by a nonstationary perturbing torque with zero mean value is under consideration. The control strategy for attitude stabilization of the rigid body is based on the usage of dissipative and restoring torques. It is assumed that the dissipative torque is linear, while restoring and perturbing torques are purely nonlinear. A theorem on sufficient conditions for asymptotic stability of the body angular position is proved on the basis of the decomposition method, the Lyapunov direct method and the averaging technique. Computer simulation results illustrating the theorem are presented.

Flight Control System Design and Autonomous Flight Control of Small-Scale Unmanned Helicopter Based on Nanosensors

Due to the limitation of the size and power, micro unmanned aerial vehicle (MUAV) usually has a small load capacity. Aiming at the problems of limited installation space and easy being interfered in flight attitude measurement of the small-scale unmanned helicopter (SUH), a low-cost and lightweight flight control system of the SUH based on ARM Cortex-M4 core microcontroller and Micro-Electro-Mechanical Systems (MEMS) sensors is developed in this paper. On this basis, in order to realize the autonomous flight control of SUH, firstly, the mathematical model of the SUH is given by using the Newton-Euler formulation. Secondly, a cascade flight controller consisting of the attitude controller and the position controller is developed based on linear active disturbance rejection control (LADRC) and proportional-integral-derivative (PID) control. Furthermore, simulations are conducted to validate the performance of the attitude controller and the position controller in MATLAB/SIMULINK simulation environment. Finally, based on the Align T-REX 470L SUH experimental platform, the hovering experiment and the route flight experiment are also carried out to validate the performance of the designed flight control system hardware and the proposed control algorithm. The results show that the flight control system designed in this paper has high reliability and strong anti-interference ability, and the control algorithm can effectively and reliably realize the attitude stabilization control and route control of the SUH, with high control accuracy and small error.

Attitude control of self-balancing vehicle based on sliding mode variable structure control

The two wheeled self balancing vehicle belongs to a typical nonlinear system. Aiming at the problem of attitude control stability of two wheeled self-balancing vehicle. A new sliding mode reaching law of integral sliding mode variable structure control was proposed. The feasibility and effetivenes of the controller are proved by theory and experiment. The experiment results show that the designed controller has remarkable advantages of steady state characteristic,fast dynamic response and strong robustness to external disturbance to compared with traditional PID controller.