Search results for "5-7"
showing 10 items of 428 documents
Performances Comparison for a Rotating Shaft Suspended by 4-Axis Radial Active Magnetic Bearings via đ -Synthesis, Loop-Shaping Design, and Sub ( đ»âŠ
2011
The control systems applied on active magnetic bearing are several. A perfect levitation is characterized by maintaining the operating point condition that is characterized by the center of stator coincident with the geometric center of shaft. The first controller implemented for this purpose is PID controller that is characterized by an algorithm that leads the amplifier to produce control current until the operating point condition is not reached, this is obtained by an integration operator. The effect of an integrator is essential but not necessary for a centered levitation for example in the robust control characterized by a dynamic model depended on plant of system so that it depends oâŠ
Modeling of Wind Turbine Gearbox Mounting
2011
In this paper three bushing models are evaluated to find a best practice in modeling the mounting of wind turbine gearboxes. Parameter identification on measurements has been used to determine the bushing parameters for dynamic simulation of a gearbox including main shaft. The stiffness of the main components of the gearbox has been calculated. The torsional stiffness of the main shaft, gearbox and the mounting of the gearbox are of same order of magnitude, and eigenfrequency analysis clearly reveals that the stiffness of the gearbox mounting is of importance when modeling full wind turbine drivetrains.
Offshore Wind Payload Transfer Using Flexible Mobile Crane
2015
This article presents an offshore-simulated loading and unloading of a payload from a floating platform to a fixed structure. The experiments are performed in a dry-lab, where a Stewart platform is used to simulate the motion of the vessel. A hydraulically actuated vehicle loader crane is used to perform the tasks of payload transfer. The crane includes a hydraulic winch where the wire force is measured by a load cell. A mathematical model of the winch is derived and is experimentally verified. The control strategies include a heave compensation and a constant tension mode. A motion reference unit is used to generate the reference motion of the moving platform. Experimental results show theâŠ
A MDA Approach for avigational and User Perspectives
2011

 
 
 The study presented in this paper focuses on a navigational and user perspectives analysis of Web applications, highlighting some of their critical points for modeling. To consider these critical points, we propose a notational definition focused on a general metamodel, consisting of three specific metamodels: the Navigational Tree, the Node, and Roles. The metamodels have been implemented with a specific MDA (Model Driven Architecture) tool called AndroMDA, to generate applications for PHP language. Both, the general metamodel and its implementation have been analyzed by means of a proof of concept. Finally, some interesting results as well as the contribution of the pâŠ
Preface to the CIbSE 2016 Special Issue
2016
Abstract: This special issue of the CLEI Electronic Journal consists of an invited paper on 25 years of Model-Driven Web Engineering as well as extended and revised versions of the Selected Papers presented at the XIX Ibero-American Conference on Software Engineering (CIbSE 2016). Resumen: Este nĂșmero especial de la revista CLEI electronic journal consiste en un paper invitado sobre los 25 años de Model-Driven Web Engineering, asĂ como un conjunto de trabajos revisados y extendidos, seleccionados de la conferencia CIbSE 2016.
Development of 3D Anti-Swing Control for Hydraulic Knuckle Boom Crane
2021
In this paper, 3D anti-swing control for a hydraulic loader crane is presented. The difference between hydraulic and electric cranes are discussed to show the challenges associated with hydraulic actuation. The hanging load dynamics and relevant kinematics of the crane are derived to model the system and create the 3D anti-swing controller. The anti-swing controller generates a set of tool point velocities which are added to the electro-hydraulic motion controller via feedforward. A dynamic simulation model of the crane is made, and the control system is evaluated in simulations with a path controller in actuator space. Simulation results show significant reduction in the load swing angles âŠ
Automated Kick Control Procedure for an Influx in Managed Pressure Drilling Operations
2016
Within drilling of oil and gas wells, the Managed Pressure Drilling (MPD) method with active control of wellbore pressure during drilling has partly evolved from conventional well control procedures. However, for MPD operations the instrumentation is typically more extensive compared to conventional drilling. Despite this, any influx of formation fluids (commonly known as a kick) during MPD operations is typically handled by conventional well control methods, at least if the kick is estimated to be larger than a threshold value. Conventional well control procedures rely on manual control of the blow out preventer, pumps, and choke valves and do not capitalize on the benefits from the instruâŠ
Modeling and Parameter Identification of Deflections in Planetary Stage of Wind Turbine Gearbox
2012
The main focus of this paper is the experimental and numerical investigation of a 750[kW] wind turbine gearbox. A detailed model of the gearbox with main shaft has been created using MSC.Adams. Special focus has been put on modeling the planet carrier (PLC) in the gearbox. For this purpose experimental data from a drive train test set up has been analyzed using parameter identification to quantify misalignments. Based on the measurements a combination of main shaft misalignment and planet carrier deflection has been identified. A purely numerical model has been developed and it shows good accordance with the experimental data.
odeling of Human Arm Energy Expenditure for Predicting Energy Optimal Trajectories
2011
Human arm motion can inspire the trajectory planning of anthropomorphic robotic arms to achieve energy-efficient movements. An approach for predicting metabolic cost in the planar human arm motion by means of the biomechanical simulation is proposed in this work. Two biomechanical models, including an analytical model and a musculoskeletal model, are developed to implement the proposed approach. The analytical model is developed by modifying a human muscle expenditure model, in which the muscles are grouped as torque providers for computation efficiency. In the musculoskeletal model, the predication of metabolic cost is conducted on the basis of individual muscles. With the proposed approacâŠ
Past, Present and Future of Process Control at Xstrata Nikkelverk
2009
MIC celebrates its 30th anniversary in 2009 and Xstrata Nikkelverk celebrates its 100th anniversary in 2010. Both anniversaries are certainly worth celebrating and with this article Xstrata Nikkelverk salutes MIC at this special occasion. This article is about process control developments at Xstrata Nikkelverk during the last 40 years. We also give an overview of the current status and a view on the current and future trends of process control at the Nikkelverk renery.