scholarly journals Implementation of automation in vibration-isolating supports of new type for engines of sea and river vessels

2021 ◽  
Vol 2142 (1) ◽  
pp. 012004
Author(s):  
P A Fomichev ◽  
E V Fomicheva
Keyword(s):  
Power Plants ◽  
Vibration Isolation ◽  
Modern Technology ◽  
Control Law ◽  
Control Laws ◽  
Active Systems ◽  
Single Process ◽  
New Type ◽  
Almost All ◽  
And Control

Abstract In almost all areas of modern technology, the problem of vibration isolation arises, which is associated with the goal of improving the quality, reliability and productivity of various technical objects. One of the important tasks of shipbuilding is to reduce vibration levels of ship power equipment. This article proposes a non-linear control law for an electromagnetic hydraulic vibration-insulating support (EGVO) for ship power plants (SEP), which allows you to compensate for external harmonic disturbances at the SEP, which leads to an increase in their technological safety. The proposed control law of EGVO has advantages over various control laws of vibration-insulating systems of an active type for SEP. The proposed method can be used to create vibration-isolating active systems for various technical objects. The essential novelty of this method is a consistent synthesis of control laws and the creation of a single process of technological self-organization and control.

scholarly journals LINEAR DYNAMIC MATHEMATICAL MODEL AND IDENTIFICATION OF MICRO TURBOJET ENGINE FOR TURBOFAN POWER RATIO CONTROL

Aviation ◽  
2019 ◽  
Vol 23 (2) ◽  
pp. 54-64 ◽  
Author(s):  
Khaoula Derbel ◽  
Károly Beneda
Keyword(s):  
Mathematical Model ◽  
Power Plants ◽  
Space Representation ◽  
Nonlinear Behaviour ◽  
Power Ratio ◽  
Linear Quadratic ◽  
Control Laws ◽  
Turbofan Engines ◽  
State Space Representation ◽  
And Control

Micro turbojets can be used for propulsion of civilian and military aircraft, consequently their investigation and control is essential. Although these power plants exhibit nonlinear behaviour, their control can be based on linearized mathematical models in a narrow neighbourhood of a selected operating point and can be extended by using robust control laws like H∞ or Linear Quadratic Integrating (LQI). The primary aim of the present paper is to develop a novel parametric linear mathematical model based on state space representation for micro turbojet engines and the thrust parameter being Turbofan Power Ratio (TPR). This parameter is used by recent Rolls-Royce commercial turbofan engines but can be applied for single stream turbojet power plants as well, as it has been proven by the authors previously. An additional goal is to perform the identification for a particular type based on measurements of a real engine. This model has been found suitable for automatic control of the selected engine with respect of TPR, this has been validated by simulations conducted in MATLAB® Simulink® environment using acquired data from transient operational modes.

Robust Trajectory Following Control of Robotic Systems

1985 ◽  
Vol 107 (4) ◽  
pp. 308-315 ◽  
Author(s):  
S. N. Singh ◽  
A. A. Schy
Keyword(s):  
Degrees Of Freedom ◽  
Digital Simulation ◽  
Robotic Systems ◽  
Control Law ◽  
Robot Arm ◽  
Control Laws ◽  
Payload Uncertainty ◽  
Trajectory Following ◽  
And Control ◽  
Three Degrees Of Freedom

Using an inversion approach we derive a control law for trajectory following of robotic systems. A servocompensator is used around the inner decoupled loop for robustness to uncertainty in the system. These results are applied to trajectory control of a three-degrees-of-freedom robot arm and control laws Cθ and CH for joint angle and position trajectory following, respectively, are derived. Digital simulation results are presented to show the rapid trajectory following capability of the controller in spite of payload uncertainty.

Continuum of Motion Equations and Control Laws for the Inverted Pendulum Cart and Rotary Pendulum

2020 ◽  
Author(s):  
Constance Lare ◽  
Warren N. White
Keyword(s):  
Inverted Pendulum ◽  
Equations Of Motion ◽  
Control Law ◽  
Control Laws ◽  
Motion Equations ◽  
Base Radius ◽  
Limiting Condition ◽  
And Control ◽  
The Given ◽  
Insight Into

Abstract This paper questions whether the controller properties for a given rigid body mechanical system still apply as the given system is changed. As a first attempt in this investigation, the controller for the underactuated rotary pendulum is investigated as the system morphs into an underactuated inverted pendulum cart. As the limiting condition of the inverted pendulum cart is approached, the investigation allows the controller to also morph. The authors show that, as the pendulum base radius grows, the rotary pendulum equations of motion morph into the inverted pendulum cart dynamics. The paper presents necessary conditions for the successful morphing of the dynamic equations. The morphing process for the controller tests the idea whether the control law also satisfies the same continuum basis as the motion equations. The paper presents a framework for the class of controllers investigated for providing insight into when the controller morphing may be successful. This paper presents dimensionless quantities that render the equations of motion and controller for the inverted pendulum cart and rotary pendulum into dimensionless form. These dimensionless quantities allow comparison of controllers and systems that are not possible through simple inspection. This comparison ability is especially useful for quantifying the nonlinearities of a given system and controller compared to another system and controller having different parameter sizes, a comparison rarely seen in the control literature.

Design Principles for Vibration Control Systems Using Semi-Active Dampers

1990 ◽  
Vol 112 (3) ◽  
pp. 448-455 ◽  
Author(s):  
D. Karnopp
Keyword(s):  
Control Systems ◽  
Vibration Isolation ◽  
Practical Interest ◽  
Similar System ◽  
Active Systems ◽  
Shock Absorbers ◽  
Servo Mechanism ◽  
Control Schemes ◽  
And Control ◽  
Prototype Phase

Electronically controlled vibration isolation and control systems have recently reached at least the prototype phase in a number of fields of application. Of particular practical interest are semi-active systems which require very little actuator power. Semi-active dampers in the form of rapidly modulated hydraulic shock absorbers have been used for example in automobile suspensions to achieve some of the benefits of fully active servo-mechanism systems but with much reduced cost and complexity. Various damper configurations and feedback control schemes are discussed. The design choices to be made can often result in similar system performance and yet can lead to dramatic differences in the frequency response requirements for the actuators used in the semi-active dampers.

The Use of Variable Fidelity Models in the Optimization Problems for Aircraft Engines Parameters and Control Laws

2000 ◽  
Author(s):  
I. N. Egorov ◽  
G. V. Kretinin ◽  
I. A. Leshchenko ◽  
Y. I. Babiy
Keyword(s):  
Power Plants ◽  
Optimization Problems ◽  
Axial Compressor ◽  
Optimization Procedure ◽  
Aircraft Engines ◽  
Control Laws ◽  
Analysis Tools ◽  
Variable Fidelity ◽  
And Control ◽  
Optimization Search

The typical situation when solving a problem of an aircraft engine optimization is that a researcher has several tools for effectiveness indices analysis, distinguished according to the levels of complexity and accuracy. The high-fidelity tools can be the detailed nonlinear mathematical models or even the experimental samples of the engine or its components. However the implementation of optimization researches using such a tools is associated with the significant time expenditures. The low-fidelity models also allow us to carry out optimization search, but the validity of the obtained results can be rather low. Therefore the methods based on a combination of various levels of the analysis tools are going to be used in the field of optimization of the aircraft engines parameters and control laws. The given paper introduces the multicriteria optimization procedure for aircraft power plants and their components. The procedure is based upon the adaptive use of different levels analysis tools. The proposed approach is intended to minimize the complicated analysis tools application. It uses the method of indirect optimization on the base of self-organization, which permits to find numerically the Pareto-optimal set of solutions, uniformly distributed in the criteria space. The effectiveness of the proposed optimization procedure is demonstrated by two examples. The first one is a problem to find the optimal control laws for the power plant of short take-off and vertical landing aircraft for its take-off (50 variables, 2 criteria). The second one is the problem of multistage axial compressor optimization aimed at its efficiency maximization (42 variables, 2 criteria).

On Aero Control Law Joined Compensatory PID for Glide down to Fixed Low Altitude System and Simulation Researches

2012 ◽  
Vol 198-199 ◽  
pp. 1021-1024
Author(s):  
De Hai Yu ◽  
Dong Cai Qu ◽  
Jian Hua Lu ◽  
Bin Wen Lu
Keyword(s):  
Control Law ◽  
Simple Analysis ◽  
Control Laws ◽  
Control Scheme ◽  
Improve Accuracy ◽  
Working Principle ◽  
Simulation Results ◽  
Low Altitude ◽  
Constant Altitude ◽  
And Control

In order to improve accuracy of constant altitude fly at low altitude and fly track of glide down to fixed altitude, aeroplane’s control scheme of glide down to fixed low altitude with PID compensatory link were designed. At the same time, the corresponding control laws had been designed. After simple analysis about working principle of the aeroplane’s control system, simulation researches were done to optimize designed control laws, so that achieving expectant requirement. Simulation results show that designed control scheme and control law were accurate and effective.

A Novel More Reliable and Extensible Architecture of Instrumentation and Control Systems

2018 ◽  
Author(s):  
Shuqiao Zhou ◽  
Chao Guo ◽  
Duo Li ◽  
Xiaojin Huang
Keyword(s):  
Communication Technology ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Traditional Architecture ◽  
Digital Instrumentation ◽  
Control Units ◽  
Computing Performance ◽  
Almost All ◽  
And Control

Digital instrumentation and control (I&C) systems are widely used in many industrial areas. In the recent years, the digitalization process for nuclear power plants has also been moving on rapidly. Full digital I&C systems are now adopted in almost all new constructed nuclear power plants. The architecture of a digital I&C system plays a pivotal role for the safety, reliability and security of the whole nuclear power plant. Moreover, for the advanced small modular reactors, both the reliability and extensibility of I&C systems are especially required. Therefore, in this paper we propose a new architecture of the digital I&C systems based on the developed computing performance and communication technology. The control units and the data servers in the new proposed architecture are decentralized and working in a mutually redundant and distributed computing/storage way. Thus the architecture is with a flexible extensibility. Moreover, other control units or data servers can take over the functions of a certain number of failed ones. This characteristic benefits the system’s reliability significantly. The reliability of the new architecture is theoretically evaluated and the results demonstrate that it is much higher than that of the traditional architecture of I&C systems.

Modelling and control of a semi-active dual-chamber hydro-pneumatic inerter-based suspension system

2021 ◽  
pp. 095440702199091
Author(s):  
Zhihao Zhu ◽  
Ruochen Wang ◽  
Lin Yang ◽  
Zeyu Sun ◽  
Xiangpeng Meng
Keyword(s):  
Vibration Isolation ◽  
Ride Comfort ◽  
Bench Test ◽  
Linear Quadratic ◽  
Dual Chamber ◽  
Isolation System ◽  
Suspension Systems ◽  
Pneumatic Suspension ◽  
New Type ◽  
And Control

This study develops a new type of semi-active dual-chamber hydro-pneumatic inerter-based suspension (SADHPIS) based on the ‘inerter–spring–damping’ vibration isolation system and semi-active control. The mathematical model of SADHPIS is linearised to match the nonlinear SADHPIS system with a linear control strategy, and the equivalent parameters are calculated. A linear–quadratic–Gaussian (LQG) controller that matches the nonlinear characteristics of the SADHPIS system is designed. Furthermore, the performance of a quarter-vehicle model with SADHPIS is analysed and compared with that with normal semi-active hydro-pneumatic suspension (SAHPS). Simulation results show that the performance of SADHPIS is better than that of SAHPS, indicating that ride comfort and handle stability are improved greatly in SADHPIS. A prototype is also developed, and a comparative bench test is conducted to verify the accuracy of the simulations. SADHPIS can realise adjustable inertia with a small space and low energy consumption. This work provides new insights for research on variable inertia, promotes the matching of inerters and hydro-pneumatic suspension systems and further proves the practical application value of hydro-pneumatic inerter-based suspension.

Human Step Rehabilitation Using a Robot Attached to the Pelvis

2004 ◽  
Author(s):  
D. Aoyagi ◽  
W. E. Inchinose ◽  
D. J. Reinkensmeyer ◽  
J. E. Bobrow
Keyword(s):  
Force Control ◽  
Control Algorithm ◽  
Control Law ◽  
Task Space ◽  
Control Laws ◽  
Position Feedback ◽  
Pelvic Motion ◽  
Linear Force ◽  
And Control ◽  
Piston Chamber

This paper describes a new robot capable of manipulating pelvic motion during human step training on a treadmill. The robot, PAM (Pelvic Assist Manipulator), uses two pneumatically actuated subsystems arranged in a tripod configuration to measure and control the pelvis of a person during body weight supported stepping on a treadmill. The device can be used in a back-drivable mode to record pelvic trajectories, either specified manually by a therapist or pre-recorded from unimpaired subjects, then replay these trajectories using a PD position feedback control law in the task space and a non-linear force control algorithm for each piston chamber. The control laws are presented, along with data that demonstrate the ability of the device to record and replay the pelvic motions that occur during normal walking.

Modified integral action with time-varying forgetting function for tracking control

2019 ◽  
Vol 234 (6) ◽  
pp. 715-725
Author(s):  
Fernando Villegas ◽  
Rogelio Hecker ◽  
Miguel Peña
Keyword(s):  
Stability Analysis ◽  
Tracking Error ◽  
Control Law ◽  
Time Varying ◽  
Forgetting Factor ◽  
Robust Controller ◽  
Integral Action ◽  
Abrupt Changes ◽  
New Type ◽  
And Control

While the use of integral action in control is quite common, in part due to its benefits for output regulation, it can also be counterproductive when abrupt changes in disturbance occur during tracking. In order to mitigate its counterproductive effect while at the same time maintaining its advantages for regulation, this work proposes a new type of integral action, including a time-varying forgetting factor suited to the expected behavior of the disturbance during tracking. Also, Lyapunov stability techniques are used to derive general results aiming to reduce the complexity of stability analysis and control design when the proposed integral action is included in a control law. In particular, these results are used for stability analysis when the proposed integral action is implemented in a deterministic robust controller for a linear motor system. Furthermore, the controller is implemented in the corresponding experimental setup, resulting in an improvement on maximum tracking error of up to 32%.

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