• Title/Summary/Keyword: Three-DOF

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Factors associated with outcomes following microvascular decompression for the treatment of primary trigeminal neuralgia in adults: a systematic review and meta-analysis

  • Pablo Gomes-da Silva de Rosenzweig;Santiago Pastrana-Brandes;Salomon Merikansky-Gerson;Luis Octavio Victoria-Garcia;Magdalena Sophia Curtius-Caruso;Jose Damian Carrillo-Ruiz
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.24 no.4
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    • pp.227-243
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    • 2024
  • This study aimed to evaluate pain assessment strategies and factors associated with outcomes after microvascular decompression for the treatment of primary trigeminal neuralgia in adults. We conducted a systematic review and meta-analysis of English, Spanish, and French literature. We searched three databases, PubMed, Ovid, and EBSCO, from 2010 to 2022 and selected studies including patients with primary trigeminal neuralgia, clear pain assessment, and pain outcomes. Population means and standard deviations were calculated. Studies that included factors associated with postoperative outcomes were included in the meta-analysis. A total of 995 studies involving 5673 patients with primary trigeminal neuralgia following microvascular decompression were included. Patients with arteries compressing the trigeminal nerve demonstrated optimal outcomes following microvascular decompression (odds ratio [OR]= 0.39; 95% confidence interval [CI] = 0.19-0.80; X2 = 46.31; Dof = 15; I2 = 68%; P = < 0.0001). Conversely, when comparing arterial vs venous compression of the trigeminal nerve (OR = 2.72; 95% CI = 1.16-6.38; X2 = 23.23; Dof = 10; I2 = 57%; P = 0.01), venous compression demonstrated poor outcomes after microvascular decompression. Additionally, when comparing single-vessel vs multiple-vessel compression (OR = 2.72; 95% CI = 1.18-6.25; X2 = 21.17; Dof = 9; I2 = 57%; P = 0.01), patients demonstrated unfavorable outcomes after microvascular decompression. This systematic review and meta-analysis evaluated factors associated with outcomes following microvascular decompression (MVD) for primary trigeminal neuralgia (PTN). Although MVD is an optimal treatment strategy for PTN, a gap exists in interpreting the results when considering the lack of evidence for most pain assessment strategies.

Equivalent modal damping ratios for non-classically damped hybrid steel concrete buildings with transitional storey

  • Sivandi-Pour, Abbas;Gerami, Mohsen;Khodayarnezhad, Daryush
    • Structural Engineering and Mechanics
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    • v.50 no.3
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    • pp.383-401
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    • 2014
  • Over the past years, hybrid building systems, consisting of reinforced concrete frames in bottom and steel frames in top are used as a cost-effective alternative to traditional structural steel or reinforced concrete constructions. Dynamic analysis of hybrid structures is usually a complex procedure due to various dynamic characteristics of each part, i.e. stiffness, mass and especially damping. In hybrid structures, one or more transitional stories with composite sections are used for better transition of lateral and gravity forces. The effect of transitional storey has been considered in no one of the studies in the field of hybrid structures damping. In this study, a method has been proposed to determining the equivalent modal damping ratios for hybrid steel-concrete buildings with transitional storey. In the proposed method, hybrid buildings are considered to have three structural systems, reinforced concrete, composite steel and concrete (transitional storey) and steel system. In this method, hybrid buildings are substituted appropriately with 3-DOF system.

Active shape exploration of an unknown object by using robot hand (로봇손을 이용한 미지 물체의 능동적 형상탐사에 관한 연구)

  • 김진호;오상록;최혁렬
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.768-771
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    • 1997
  • Geometric probing addresses the problem of determining geometric aspects of a structure from the mathematics and results of a physical measuring device such as a probe. This paper presents a new algorithm to recognize the shape of an unknown object by using a robot hand with a force and torque sensor. The new algorithm is called S.E.P.(Shape Exploration Procedure) which finds the global shape of an unknown object. The proposed method is composed of three major parts, finding contact informations such as contact point, calculation of shape information such as curvature, and expression of global shape from these informations. Comparing with the conventional approaches, the advantages of the proposed method are explained and verified by conducting experiments with a 3-dof SCARA robot.

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A Full Order Sliding Mode Tracking Controller For A Class of Uncertain Dynamical System

  • Ahmad, M.N.;Nawawi, S.W.;Osman, J.H.S
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1853-1858
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    • 2004
  • This paper presents the development of a full order sliding mode controller for tracking problem of a class of uncertain dynamical system, in particular, the direct drive robot manipulators. By treating the arm as an uncertain system represented by its nominal and bounded parametric uncertainties, a new robust fullorder sliding mode tracking controller is derived such that the actual trajectory tracks the desired trajectory as closely as possible despite the non-linearities and input couplings present in the system. A proportional-integral sliding surface is chosen to ensure the stability of overall dynamics during the entire period i.e. the reaching phase and the sliding phase. Application to a three DOF direct drive robot manipulator is considered.

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Omni-tread Type Snake Robot: Mathematical Modeling and Implementation (Omni-tread 뱀 로봇 모델링 및 개발)

  • Oh, Sang-Jin;Lee, Ji-Hong;Choi, Hoon
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.10
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    • pp.1022-1028
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    • 2008
  • This article presents an omni-tread snake robot that designed to locomote on narrow space and rough terrain. The omni-tread snake robot comprises three segment, which are linked to each other by 2 degrees of freedom joints for the pitch and yaw motion. Moving tracks on all four sides of each segment guarantee propulsion even when the robot rolls over. The 2 DOF joint are actuated by 2 servo motors which produce sufficient torque to lift the one leading or trailing segments up and overcome obstacles. This paper applies articulated steering technique to get omni-tread snake robot's kinematics model.

Precise Measurement Method of Radial Artery Pulse Waveform using Robotic Applanation Tonometry Sensor (로보틱 토노메트리 센서를 이용한 요골 동맥 파형 정밀 측정 방법)

  • Kim, Young-Min
    • Journal of Sensor Science and Technology
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    • v.26 no.2
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    • pp.135-140
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    • 2017
  • In this paper, a novel measurement method of radial artery pulse waveform using robotic applanation tonometry (RAT) was present to reduce the errors by the pressing direction of the vessel. The RAT consisted of an array of pressure sensors and 2-axis tilt sensor, which was attached to the universal joint with a linear spring and five-DOF robotic manipulator with a one-axis force sensor. Using the RAT mechanism, the pulse sensor could be manipulated to perpendicularly pressurize the radial artery. A pilot experimental result showed that the proposed mechanism could find the optimal pressurization angles of the pulse sensor within ${\pm}3^{\circ}$standard deviations. Coefficient values of variation of maximum pulse peaks extracted from the pulse waveforms were 4.692, 6.994, and 11.039 % for three channels with the highest magnitudes. It is expected that the proposed method can be helpful to develop more precise tonometry system measuring the pulse waveform on the radial artery.

ROBUST CONTROLLER DESIGN FOR IMPROVING VEHICLE ROLL CONTROL

  • Du, H.;Zhang, N
    • International Journal of Automotive Technology
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    • v.8 no.4
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    • pp.445-453
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    • 2007
  • This paper presents a robust controller design approach for improving vehicle dynamic roll motion performance and guaranteeing the closed-loop system stability in spite of vehicle parameter variations resulting from aging elements, loading patterns, and driving conditions, etc. The designed controller is linear parameter-varying (LPV) in terms of the time-varying parameters; its control objective is to minimise the $H_{\infty}$ performance from the steering input to the roll angle while satisfying the closed-loop pole placement constraint such that the optimal dynamic roll motion performance is achieved and robust stability is guaranteed. The sufficient conditions for designing such a controller are given as a finite number of linear matrix inequalities (LMIs). Numerical simulation using the three-degree-of-freedom (3-DOF) yaw-roll vehicle model is presented. It shows that the designed controller can effectively improve the vehicle dynamic roll angle response during J-turn or fishhook maneuver when the vehicle's forward velocity and the roll stiffness are varied significantly.

Design of a large deflection 2 DOF scanning mirror using an electromagnetic force (전자기력을 이용한 대변위 구동 2축 스캐닝 미러의 설계)

  • Lee, Kyoung-Gun;Jang, Yun-Ho;Yoo, Byung-Wook;Jin, Joo-Young;Lim, Yong-Geun;Kim, Yong-Kweon
    • Proceedings of the KIEE Conference
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    • 2008.10a
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    • pp.181-182
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    • 2008
  • In this paper, we present the design of an electromagnetic scanning mirror with rotated serpentine springs. We considered three types of torsional springs: simple beam springs (SBS), classic serpentine springs (CSS), and rotated serpentine springs (RSS). The analysis was done for an electrical resistance, differences in the mode-frequency, and resonances regarding to spring thickness. Electromagnetic coils under the mirror plate were also analyzed for power consumption and the mechanical deflection. From the analysis result, RSS and electromagnetic coils were designed for the silicon scanning mirror.

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Vehicle Stability Analysis using a Non-linear Simplified Model (비선형 단순 모델을 이용한 차량 안정성 해석)

  • Ko, Young-Eun;Song, Chul-Ki
    • Transactions of the Korean Society of Automotive Engineers
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    • v.16 no.4
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    • pp.29-37
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    • 2008
  • Vehicle stability is a very important subject in vehicle design and control, because vehicle safety is closely dependent upon its dynamic stability. For the vehicle stability analysis, the nonlinear vehicle model of a mid-size car with three DOF - longitudinal, lateral and yaw - is employed. A rigorous method is used to determine the vehicle stability region in plane motion. An algorithm is used to materialize a topology theorem, which enables to find the exact stability region. A stability criterion for the critical cornering is proposed.

Identification of 18 flutter derivatives by covariance driven stochastic subspace method

  • Mishra, Shambhu Sharan;Kumar, Krishen;Krishna, Prem
    • Wind and Structures
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    • v.9 no.2
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    • pp.159-178
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    • 2006
  • For the slender and flexible cable supported bridges, identification of all the flutter derivatives for the vertical, lateral and torsional motions is essential for its stability investigation. In all, eighteen flutter derivatives may have to be considered, the identification of which using a three degree-of-freedom elastic suspension system has been a challenging task. In this paper, a system identification technique, known as covariance-driven stochastic subspace identification (COV-SSI) technique, has been utilized to extract the flutter derivatives for a typical bridge deck. This method identifies the stochastic state-space model from the covariances of the output-only (stochastic) data. All the eighteen flutter derivatives have been simultaneously extracted from the output response data obtained from wind tunnel test on a 3-DOF elastically suspended bridge deck section-model. Simplicity in model suspension and measurements of only output responses are additional motivating factors for adopting COV-SSI technique. The identified discrete values of flutter derivatives have been approximated by rational functions.