Roll Maneuver Research Articles

Positional Dizziness

This article reviews the most common conditions that are caused by changes in head or body positions. Practical clinical methods to help distinguish vestibular from nonvestibular and central from peripheral vestibular positional dizziness are discussed. This article also reviews the treatment methods of selected canal variants of benign paroxysmal positional vertigo (BPPV). Two recent evidence-based guidelines have established canalith repositioning maneuvers (Epley and Semont maneuvers) as safe and highly effective in the treatment of posterior canal BPPV. Recent studies suggest the Gufoni and the Lempert roll (barbecue) maneuvers are effective in treating lateral canal forms of BPPV. Most cases of positional vertigo are of peripheral vestibular origin and can be effectively treated by simple positioning maneuvers. This article reviews the variants of BPPV encountered in clinical practice, including mechanistic cause, differential diagnosis, prognosis, and treatment. Generous use of figures is intended to aid in understanding the most effective treatment maneuver techniques for the more common forms of BPPV. Clinicians who can recognize the types of nystagmus associated with the various canal types of BPPV can usually recognize CNS causes as distinct.

SIMULASI GERAK DAN ANALISIS KESTABILAN KOPLING INERSIA WAHANA DIRGANTARA DENGAN BENTUK BADAN RAMPING

Inertia coupling is a motion phenomenon of a high-speed airplane having slender body and low aspect ratio. This inertia coupling happens when the aircraft performs a roll manoeuvre motion with a high roll rate. This paper will discuss the derivation of inertia coupling equations of motion, modelling equations of motion in the Matlab/Simulink software, simulating the dynamics motion, and analyzing the stability of the inertia coupling. Numerical simulation and stability analysis of the inertia coupling for a fighter aircraft will be presented in this paper. Keywords:Inertia coupling, Stability analysis, Flight simulation, Slender body

The clinical characteristics of the benign paroxysmal positional vertigo associated with sudden sensorineural hearing loss

To explore the clinical characteristics of the benign paroxysmal positional vertigo (BPPV) associated with sudden sensorineural hearing loss (SSHL) (throughretrospective analysis of 19 cases from June 2008 to June 2010) and improve the diagnosis and treatment. Nineteen cases (7 male and 12 female, aged 46 to 68 years old) of BPPV associated with SSHL from June 2008 to June 2010 were retrospectively analyzed. All the patients were diagnosed SSHL by history and pure tone threshold test. Positional paroxysmal vertigo was diagnosed by Hallpike test or roll test. Epley maneuver or Barbecue roll maneuver were used to treat according to the type of BPPV, and the efficacy was evaluated by symptom and Hallpike test. 63.2% cases were female patients in the study; BPPV occurred after SSHL in all of the cases (all in the hearing loss ears), of which 15 cases were posterior semicircular canal lithiasis and 4 cases were horizontal semicircula canal lithiasis (only 1 case was cupula lithiasis); 15 out of 19 patients had BPPV within 2 weeks after SSHL;BPPV was cured in all cases after several times of posture treatments. BPPV can result from SSHL. A possible mechanism may be the inner ear circulation disorder or virus infection that lead to otolith falling off. Most cases of BPPV occurred in the posterior semicircular canal of the diseased ear. Otolith reposition is an effective treatment for BPPV secondary to SSHL. Key words: Benign paroxysmal positional vertigo, sudden sensorineural hearing loss, otolith.

Eliminating log rolling as a spine trauma order.

Background:Currently, up to 25% of patients with spinal cord injuries may experience neurologic deterioration during the initial management of their injuries. Therefore, more effective procedures need to be established for the transportation and care of these to reduce the risk of secondary neurologic damage. Here, we present more acceptable methods to minimize motion in the unstable spine during the management of patients with traumatic spine injuries.Methods:This review summarizes more than a decade of research aimed at evaluating different methods of caring for patients with spine trauma.Results:The most commonly utilized technique to transport spinal cord injured patients, the log rolling maneuver, produced more motion than placing a patient on a spine board, removing a spine board, performing continuous lateral therapy, and positioning a patient prone for surgery. Alternative maneuvers that produced less motion included the straddle lift and slide, 6 + lift and slide, scoop stretcher, mechanical kinetic therapy, mechanical transfers, and the use of the operating table to rotate the patient to the prone position for surgical stabilization.Conclusions:The log roll maneuver should be removed from the trauma response guidelines for patients with suspected spine injuries, as it creates significantly more motion in the unstable spine than the readily available alternatives. The only exception is the patient who is found prone, in which case the patient should then be log rolled directly on to the spine board utilizing a push technique.

Determining Vertical Water Velocities from Seaglider

Abstract Vertical velocities in the world’s oceans are typically small, less than 1 cm s−1, posing a significant challenge for observational techniques. Seaglider, an autonomous profiling instrument, can be used to estimate vertical water velocity in the ocean. Using a Seaglider’s flight model and pressure observations, vertical water velocities are estimated along glider trajectories in the Labrador Sea before, during, and after deep convection. Results indicate that vertical velocities in the stratified ocean agree with the theoretical Wentzel–Kramers–Brillouin (WKB) scaling of w; and in the turbulent mixed layer, scale with buoyancy, and wind forcing. It is estimated that accuracy is to within 0.5 cm s−1. Because of uncertainties in the flight model, velocities are poor near the surface and deep apogees, and during extended roll maneuvers. Some of this may be improved by using a dynamic flight model permitting acceleration and by better constraining flight parameters through pilot choices during the mission.

Soaring and manoeuvring flight of a steppe eagle Aquila nipalensis

We used an onboard inertial measurement unit, together with onboard and ground-based video cameras, to record the movements of the body, wings and tail of a steppe eagle Aquila nipalensis during wide-ranging flight. The eagle's flight consisted of a more or less continuous sequence of banked turns, interrupted by occasional wing tucks and roll-over manoeuvres, and ultimately terminated by a wing-over manoeuvre leading in to a diving landing approach. The flight configuration of the bird, and its pattern of movement during angular perturbations, together suggest that the eagle is inherently stable in pitch and yaw, and perhaps also in roll. The control inputs used to generate roll moments during banked turns were too subtle to be detected. Control of yaw and pitch during banked turns involved a consistent pattern of tail movement, wherein the tail was spread and depressed immediately before the turn, and then overbanked with respect to the bird during the latter part of the turn. Differential adjustment of wing posture is probably also involved in the control of banked turns, but it was only consistently apparent during more extreme roll manoeuvres. For example, roll-over and wing-over manoeuvres were both accomplished by differential changes in the angle of incidence and spread of the wings. In general, however, the bird appeared to maintain positive loading on its wings at all times, except during extreme flight manoeuvres.

Flutter of Aircraft Wings Carrying a Powered Engine Under Roll Maneuver

The flutter analysis of a swept aircraft wing-store configuration subjected to follower force and undergoing a roll maneuver is presented. Concentrated mass, follower force, and roll angular velocity terms are combined in the governing equations, which are obtained using the Hamilton's variational principle. The wing is modeled from a classical beam theory and incorporates bending-torsion flexibility. Heaviside and Dirac delta functions are used to consider the location and properties of the external mass and the follower force. Also, Peters's unsteady aerodynamic pressure loadings is considered and modified to take into account the effect of the wing sweep angle. The extended Galerkin's method is applied to convert the partial differential equations into a set of ordinary differential equations. Numerical simulations are validated with available published results. Simulation results are presented to show the effects on the wing flutter of the roll angular velocity, sweep angle, follower force, and store mass and its location. Results are indicative of the significant effect of the rigid-body roll angular velocity and the follower force on the wing-store dynamic stability. Furthermore, it is shown that the distances between the wing root and the aircraft center of gravity, acting location of the roll angular velocity, considerably affects the wing-engine flutter speed and frequency

Rolling into Spatial Disorientation: Simulator Demonstration of the Post-Roll (Gillingham) Illusion

Spatial disorientation (SD) is still a contributing factor in many aviation accidents, stressing the need for adequate SD training scenarios. In this article we focused on the post-roll effect (the sensation of rolling back after a roll maneuver, such as an entry of a coordinated turn) and investigated the effect of roll stimuli on the pilot's ability to stabilize their roll attitude. This resulted in a ground-based demonstration scenario for pilots. The experiments took place in the advanced 6-DOF Desdemona motion simulator, with the subject in a supine position. Roll motions were either fully automated with the subjects blindfolded (BLIND), automated with the subject viewing the cockpit interior (COCKPIT), or self-controlled (LEAD). After the roll stimulus subjects had to cancel all perceived simulator motion without any visual feedback. Both the roll velocity and duration were varied. In 68% of all trials subjects corrected for the perceived motion of rolling back by initiating a roll motion in the same direction as the preceeding roll. The effect was dependent on both rate and duration, in a manner consistent with semicircular canal dynamics. The effect was smallest in the BLIND scenario, but differences between simulation scenarios were non-significant. The results show that the effects of the post-roll illusion on aircraft control can be demonstrated adequately in a flight simulator using an attitude control task. The effect is present even after short roll movements, occurring frequently in flight. Therefore this demonstration is relevant for spatial disorientation training programs for pilots.

Application of piezoelectric fiber composite actuator to aircraft wing for aerodynamic performance improvement

The application of actuator made of piezoelectric material, particularly the advanced piezoelectric fiber composite due to the rapid development of smart materials and structures and active control technology in aviation and aerospace industry, to aircraft for performance enhancements such as flight control, aerodynamic force optimization, structure weight reduction, and overall aircraft design represents a new challenge to researches. It is considered as one of the key technologies for developing future flight vehicle. An approach with virtual control surface instead of conventional control surface to control aerodynamic force distribution and flight performance by use of piezoelectric fiber composite actuators distributed on wing surface is presented here. Particularly, the design and implementation of increasing lift force, providing roll maneuver, decreasing induced drag and wing root moment in different flight environments by the same structure control platform are studied. The control effect and sensitivity are examined quantitatively. Generally speaking, better control effect can be obtained by making better use of aeroelastic character to enlarge the actuation strain produced by piezoelectric material.

Analysis and Control of Attitude Motion for Rapid Regional Scanning Earth Observations

Normal Earth observation satellites operate under a nadir-pointing stabilization mode. The effective swath width of observation is limited by the camera’s field-of-view (FOV). In order to achieve continuous and wide swath coverage, a rapid regional scanning observation mode is proposed and analyzed in this paper. Periodic maneuvering about the roll axis is needed to fulfill the mission requirement. A zigzag-like trajectory is developed as a tracking reference trajectory. A sliding mode control algorithm is exploited to achieve high-precision tracking performance. Then, a mixed steering logic utilizing two symmetric-configured control moment gyros (CMG) and three orthogonal-placed magnetic torquers (MTQ) is proposed. CMGs provide large torque for rapid roll maneuvering, and MTQs help to compensate pitch angular velocity bias introduced by the orbital motion. The feasibility of the proposed strategy is verified through numerical simulations. Moreover, this strategy will be further demonstrated on the fourth small satellite, named TSUBAME, designed by the Laboratory of Space Systems at the Tokyo Institute of Technology. TSUBAME is equipped with an ultra-small optical camera designed by the Kimura Laboratory at Tokyo University of Science.

Clinical analysis of benign paroxysmal positional vertigo secondary to Menieres disease

In the present study, the clinical characteristics of 15 cases of benign paroxysmal positional vertigo (BPPV) secondary to Meniere’s disease (MD) were retrospectively analyzed, in order to improve the diagnosis and therapeutic efficacy. Patients clinically characterized as positional paroxysmal vertigo were diagnosed as MD by electrocochleography (ECochG) and glycerol test and were confirmed as BPPV associated with MD by Dix-Hallpike test and roll test. They were treated with Epley maneuver or Barbecue roll maneuver according to the type of BPPV, and the efficacy was evaluated. BPPV occurred after MD in all of the cases, of which 13 cases were posterior semicircular canal lithiasis and 2 cases were horizontal semicircular canal lithiasis. In this study, 10 patients were cured after 3 to 4 times of posture treatment (66.7%), 4 patients were cured after no less than 5 times and 1 patient received endolymphatic sac decompression because of recurrent vertigo. BPPV can result from MD, and a possible mechanism may be the hydrolabyrinth that lead to otolith falling off. BPPV occurred in the ipsilateral posterior semicircular canal in majority of cases, with an obvious sexual bias to female. Otolith reposition is an effective method to treat BPPV secondary to MD, while it is refractory compared to simple BPPV and requires multiple times of treatments. This may be related to the recurrence of hydrolabyrinth. Key words: Meniere’s disease, benign paroxysmal positional vertigo.

Sitting-up vertigo and trunk retropulsion in patients with benign positional vertigo but without positional nystagmus

BackgroundPresently, the unambiguous diagnosis of benign paroxysmal positioning vertigo (BPPV) requires the detection of positioning or positional nystagmus provoked by Dix–Hallpike (for vertical semicircular canals) or supine roll (for horizontal...

ACTIVE CONTROL OF ROLLING MANOEUVRES OF A ROBOTIC FINGER WITH HEMISPHERICAL TIP

In this paper we are concerned with the problem of sensory motor coordination of a robotic finger in order to evoke rolling maneuvers in a force-positioning task on a flat rigid surface. We use two different approaches to modeling the reaction of the soft fingertip with the contacted surface. Firstly, we assume that the environment imposes a purely kinematic rolling constraint on the end-effector motion in the tangent direction of the contacted surface. This implies no energy transfer or dissipation between the fingertip and the environment due to frictional forces. On the other hand, we assume that it is feasible for the fingertip to slip in which case pure rolling motion could be disturbed. The two different models are subsequently used to show by simulation that control laws, which have been designed on a rolling constraint dynamic model for frictional forces, fail to perform rolling in various environments. An extra control input that uses a reference rolling trajectory that is state dependent is proposed, which, if superimposed on a conventional force-position control law, can achieve rolling even on a surface with low friction characteristics. The proposed feedback signal does not utilize the modeling information in the control formulation, and thus permits easy implementation. Finally, the total controller is shown to achieve asymptotic convergence to the desired force-positioning task by simultaneously evoking pure rolling motion for the fingertip.

Are scoop stretchers suitable for use on spine-injured patients?

Introduction In the prehospital setting, spine-injured patients must be transferred to a spine board to immobilize the spine. This can be accomplished using both manual techniques and mechanical devices. Objectives The study aimed to evaluate the effectiveness of the scoop stretcher to limit cervical spine motion as compared to 2 commonly used manual transfer techniques. Methods Three-dimensional angular motion generated across the C5-C6 spinal segment during execution of 2 manual transfer techniques and the application of a scoop stretcher was recorded first on cadavers with intact spines and then repeated after C5-C6 destabilization. A 3-dimensional electromagnetic tracking device was used to measure the maximum angular and linear motion produced during all test sessions. Results Although not statistically significant, the execution of the log roll maneuver created more motion in all directions than either the lift-and-slide technique or with scoop stretcher application. The scoop stretcher and lift-and-slide techniques were able to restrict motion to a comparable degree. Conclusion The effectiveness of the scoop stretcher to limit spinal motion in the destabilized spine is comparable or better than manual techniques currently being used by primary responders.

Effects of Rolling Maneuver on Divergence and Flutter of Aircraft Wing Store

The effects of the rolling maneuver on the static and dynamic aeroelastic instabilities of a cantilever wing with an external store are investigated. The structural model is based on the Goland wing and unsteady aerodynamic pressure loadings are considered. To accurately consider the spanwise location and properties of the attached external mass, the generalized function theory is used. The aeroelastic governing equations are proposed using Hamilton’svariationalprincipleandincludecouplingbetweentherollangularvelocityofthemaneuverandthewing elastic degreesof freedom. Thesolution to the resulting partialdifferential equationsis followed byanapplication of the extended Galerkin method. Numerical simulations are validated against the exact flutter speed of the Goland wing and available theoretical and experimental results. In addition, the effects of the roll angular velocity, sweep angle, and store mass and location on the wing divergence and flutter are illustrated.

Comparing Cervical Spine Motion With Different Halo Devices in a Cadaveric Cervical Instability Model

Biomechanical evaluation of conventional and noninvasive halos in cadaveric C1-C2 and C5-C6 instability models. To compare the ability of a conventional halo and noninvasive halo (NIH) to immobilize the unstable cervical spine at the C1-C2 and C5-C6 levels. Many successful outcomes have been reported in cervical spine injury treatment with the conventional halo (CH); however, complications related to pin sites have been reported. The NIH was designed to overcome these complications. To date, no investigation has compared the biomechanical efficacy of the NIH with that of the CH in restricting three-dimensional cervical spine motion. A global instability was created at the C1-C2 level in 4 cadavers and at C5-C6 in 4 others. Relative motion was measured between the superior and inferior vertebrae during the donning process, execution of the log roll technique, and during the process of sitting up. This testing sequence was followed for all treatment conditions. During the application of the orthoses there was a significant increase in motion at C1-C2 instability and a trend toward increased motion at the C5-C6 instability with CH compared with NIH. In the log roll maneuver, the CH and NIH restrict motion to a similar degree at the C1-C2 instability level, except in frontal plane translation, where CH immobilizes the segment to a greater extent. For the C5-C6 instability the CH provides significantly better immobilization for lateral bending and axial translation. No significant differences were found between the NIH and CH for the sit-up maneuver at either of the levels. Donning of the NIH generates significantly less cervical spine motion than application of the CH. The CH provides superior immobilization for a C5-C6 instability during the log roll maneuver and a C1-C2 instability in the frontal plane during the log-roll maneuver. The CH and NIH immobilize the C1-C2 and C5-C6 instability to a similar degree during the sit-up maneuver.

The THEMIS Constellation

The Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission is the fifth NASA Medium-class Explorer (MIDEX), launched on February 17, 2007 to determine the trigger and large-scale evolution of substorms. The mission employs five identical micro-probes (termed “probes”), which have orbit periods of one, two and four days. Each of the Probes carries five instruments to measure electric and magnetic fields as well as ions and electrons. Each probe weighs 134 kg including 49 kg of hydrazine fuel and measures approximately 0.8×0.8×1.0 meters (L×W×H) and operates on an average power budget of 40 watts. For launch, the Probes were integrated to a Probe Carrier and separated via a launch vehicle provided pyrotechnic signal. Attitude data are obtained from a sun sensor, inertial reference unit and the instrument Fluxgate Magnetometer. Orbit and attitude control use a RCS system having two radial and two axial thrusters for roll and thrust maneuvers. Its two fuel tanks and pressurant system yield 960 meters/sec of delta-V, sufficient to allow Probe replacement strategies. Command and telemetry communications use an S-band 5 watt transponder through a cylindrical omni antenna with a toroidal gain pattern. This paper provides the key requirements of the probe, an overview of the probe design and how they were integrated and tested. It includes considerations and lessons learned from the experience of building NASA’s largest constellation.

Use of Bifurcation And Continuation Methods For Aircraft Trim And Stability Analysis - A State-of-the-art

The bifurcation and continuation methodology has evolved over the last two decades into a powerful tool for the analysis of trim and stability problems in aircraft flight dynamics. Over the years, bifurcation methods have been employed to deal with a variety of problems in aircraft dynamics, such as predicting high angle of attack behavior, especially spin, and studying instabilities in rolling maneuvers. The bifurcation methodology has served as a tool for the design of flight control systems, and is promising to be a useful tool in the aircraft design, simulation, testing, and evaluation process. In the present paper, we describe the state-of-theart in the use of bifurcation and continuation methods for the analysis of aircraft trim and stability with a few illustrative examples. Both the standard and extended bifurcation analysis procedures are discussed and typical results for instabilities in high-α flight and inertia-coupled roll maneuvers are shown. This is followed by several problems in nonlinear flight dynamics where bifurcation and continuation methods have been fruitfully applied to yield effective solutions. Finally, the use of bifurcation theory to arrive at analytical instability criteria is demonstrated for the aircraft roll coupling and wing rock problems. 78 references have been cited in the text.

Recruitment of the diaphragmaticus, ischiopubis and other respiratory muscles to control pitch and roll in the American alligator (Alligator mississippiensis)

We used electromyography on juvenile American alligators to test the hypothesis that the following muscles, which are known to play a role in respiration, are recruited for aquatic locomotion: M. diaphragmaticus, M. ischiopubis, M. rectus abdominis, M. intercostalis internus, and the M. transversus abdominis. We found no activity with locomotion in the transversus. The diaphragmaticus, ischiopubis, rectus abdominis and internal intercostals were active when the animals executed a head-down dive from a horizontal posture. Weights attached to the base of the tail resulted in greater electrical activity of diaphragmaticus, ischiopubis and rectus muscles than when weights were attached to the head, supporting a role of this musculature in locomotion. The diaphragmaticus and rectus abdominis were active unilaterally with rolling maneuvers. Although the function of these muscles in locomotion has previously been unrecognized, these data raise the possibility that the locomotor function arose when Crocodylomorpha assumed a semi-aquatic existence and that the musculoskeletal complex was secondarily recruited to supplement ventilation.

Topology Optimization of a Reinforced Wing Box for Enhanced Roll Maneuvers

In this paper, the aileron reversal speed of a wing torsion box is maximized by reinforcing its upper skin. We propose a topology optimization approach using the spectral level set methodology. This is based on the level set methods,which represent theinterface describing thereinforcements asthe zerolevel setofafunction. Accordingto the proposed methodology, this function is discretized using its Fourier coefficients. These coefficients become the design variables of the optimization problem assigned to define the reinforcing layout. Results show that approximately the sameoptimal reinforcement layout isobtained from topologically different initialconfigurations. The two underlying ideas of the present work are to propose the spectral level set methodology as a framework for topology optimization, given its potential for reducing the design space dimension, and, considering the possibilities of new custom-made materials, to readdress the reinforcement perspective in aircraft structures without the weight penalty. Nomenclature ai,bi = problem domain boundaries corresponding to componenti ofx at = � t smoothness parameter aV = � V smoothness parameter a0 = lift curve slope bt = minimum thickness C = positive constant Cl� = derivative of the rolling moment coefficient of the rigid airplane with respect to� C �� � y;n� = twist aty produced by a unit moment at�