scholarly journals Some special specifics of dimensioning of a hydraulic cylinder as an executive device of an electrohydraulic actuator system

2021 ◽  
Author(s):  
Dragan Nauparac ◽  
Nemanja Višnjić
Keyword(s):  
Control Algorithm ◽  
Hydraulic Cylinder ◽  
Pi Control ◽  
Control Law ◽  
Operating Pressure ◽  
Unstable System ◽  
Dynamic Criterion ◽  
Actuator System ◽  
The Stability ◽  
System 1

The hydraulic cylinder is dimensioned based on a static or dynamic criterion, assuming the desired operating pressure. The paper further analyzes the dimensioning of cylinders according to different load categories. The sizing of the hydraulic cylinder affects the choice of control algorithm parameters but also the stability of the system. How the cylinder dimension and the gain of the distributor affect the choice of the integral constant in the control algorithm in the case when we have the PI control law is especially considered. Then we have by definition an unsTable system 1 / s2 to which we provide stability through feedback.

scholarly journals Stability of the dynamic shifting process in the vehicle transmission with the input shaper

2018 ◽  
Vol 211 ◽  
pp. 02007 ◽  
Author(s):  
Alexander Taratorkin ◽  
Victor Derzhanskii ◽  
Igor Taratorkin
Keyword(s):  
Numerical Simulation ◽  
Natural Frequency ◽  
Control Algorithm ◽  
Control Law ◽  
Single Node ◽  
Input Shaper ◽  
Inertial Parameters ◽  
Wheel Drive ◽  
And Performance ◽  
The Stability

This paper investigates stability of the dynamic process of gear shift in the vehicle transmission with the input shapers (IS) taking in consideration uncertainty of the natural frequency of the mechanical system. The proposed control algorithm increases the stability of the researched system with variation of its elastic and inertial parameters. The control law with guaranteed asymptotic stability is obtained for full load of the vehicle when the all-wheel drive is turned on. The monitoring of the state and performance of the required parameters for the regulation of input shapers are tested by means of numerical simulation. Analyzing the results it is established that the best stability is reached by the adaptive setting of the input shapers in accordance with controlled value of the natural frequency of the lowest single-node mode.

scholarly journals A new experimental ground vehicle with hybrid control and hybrid vision sensor

2010 ◽  
Vol 8 (03) ◽  
Author(s):  
J. M. Rendón-Mancha ◽  
G. Sanahuja ◽  
P. Castillo ◽  
R. Lozano
Keyword(s):  
Control Algorithm ◽  
Hybrid Control ◽  
Vision System ◽  
Sampling Period ◽  
Control Law ◽  
Continuous Control ◽  
Ground Vehicle ◽  
The Stability ◽  
Real Time Application ◽  
Made In

This paper presents a new hybrid control algorithm based on saturation functions and its real-time application to a ground vehicle. The hybrid control is developed from a nonlinear continuous control law and the objective is to obtain the optimal sampling period to apply the controller in real experiences. The stability analysis was made in discrete time. The experimental platform is composed of a remote control toy car and a vision system. The vision system is built using a simple webcam and a diode laser. This system is fast, accurate, inexpensive and easy to implement. Simulations and experiments show the stability and robustness of the closed-loop system. The proposed control law performance is compared with a linear control algorithm.

scholarly journals An optimization algorithm for a better PID controller

2014 ◽  
Vol 17 (2) ◽  
pp. 5-12
Author(s):  
Tung Thanh Luu ◽  
Nhan Le
Keyword(s):  
Differential Equations ◽  
Optimization Algorithm ◽  
Pid Controller ◽  
Control Algorithm ◽  
Equations Of Motion ◽  
Control Law ◽  
End Effector ◽  
Precise Position ◽  
Accurate Model ◽  
The Stability

A controller of a manipulator has studied and discussed for many years. However, many problems in controlling the precise position of the end effector are still continuing to be studied. To solve the precision of the Robot, two problems are attended. The first thing is to find the accuracy model of dynamics. The second thing is a controller for control law. However, it is so difficult to find an accurate model or differential equations of motion which is similar to the true manipulator. In addition, some unknown influences on the manipulator will make the accurate differential equations unworthy. Thus, a control algorithm will be introduced with PID controller which coefficients Kp, Kd, Ki are compensated by compensator found from optimization algorithm. With the new algorithm, the results have proved the stability and precision are better.

Research on Simulation of SRM Drive System Based on Simulink

2012 ◽  
Vol 215-216 ◽  
pp. 1327-1330
Author(s):  
Xiang Zhong Meng ◽  
Jiang Hong Wang
Keyword(s):  
Control System ◽  
Control Algorithm ◽  
Control Method ◽  
Drive System ◽  
Pi Control ◽  
Switched Reluctance ◽  
Reluctance Motor ◽  
The Stability ◽  
Motor Drive System ◽  
Better Than

A well-performed switched reluctance motor drive system was designed, and the diagram of the hardware on the basis of control system by TMS320F28335 chip was given. A fuzzy PI control method is developed to control SRM in drive system. On the platform of MATLAB/Simulink, the SRM drive system was researched and simulated. The stability of system is analyzed. The results indicated that the performance of SRM speed control system by fuzzy PI control algorithm is obviously better than that by conventional PI control algorithm.

scholarly journals Research of Active Power Filter Modeling with Grid Impedance in Feedback Linearization and Quasi-Sliding Mode Control

2017 ◽  
Vol 2017 ◽  
pp. 1-11
Author(s):  
Zeyu Shi ◽  
Yingpin Wang ◽  
Yunxiang Xie ◽  
Lanfang Li ◽  
Xiaogang Xu
Keyword(s):  
Sliding Mode Control ◽  
Feedback Linearization ◽  
Control Algorithm ◽  
Sliding Mode ◽  
Active Power Filter ◽  
Active Power ◽  
Pi Control ◽  
Power Filter ◽  
Mode Control ◽  
Grid Impedance

Active power filter (APF) is the most popular device in regulating power quality issues. Currently, most literatures ignored the impact of grid impedance and assumed the load voltage is ideal, which had not described the system accurately. In addition, the controllers applied PI control; thus it is hard to improve the compensation quality. This paper establishes a precise model which consists of APF, load, and grid impedance. The Bode diagram of traditional simplified model is obviously different with complete model, which means the descriptions of the system based on the traditional simplified model are inaccurate and incomplete. And then design exact feedback linearization and quasi-sliding mode control (FBL-QSMC) is based on precise model in inner current loop. The system performances in different parameters are analyzed and dynamic performance of proposed algorithm is compared with traditional PI control algorithm. At last, simulations are taken in three cases to verify the performance of proposed control algorithm. The results proved that the proposed feedback linearization and quasi-sliding mode control algorithm has fast response and robustness; the compensation performance is superior to PI control obviously, which also means the complete modeling and proposed control algorithm are correct.

scholarly journals Disturbance compensation-based output feedback adaptive control for shape memory alloy actuator system

2021 ◽  
Vol 18 (1) ◽  
pp. 172988142199399
Author(s):  
Xiaoguang Li ◽  
Bi Zhang ◽  
Daohui Zhang ◽  
Xingang Zhao ◽  
Jianda Han
Keyword(s):  
Adaptive Control ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Control Method ◽  
Control Law ◽  
Reference Trajectory ◽  
Disturbance Compensation ◽  
Comparison Results ◽  
Control Scheme ◽  
Actuator System

Shape memory alloy (SMA) has been utilized as the material of smart actuators due to the miniaturization and lightweight. However, the nonlinearity and hysteresis of SMA material seriously affect the precise control. In this article, a novel disturbance compensation-based adaptive control scheme is developed to improve the control performance of SMA actuator system. Firstly, the nominal model is constructed based on the physical process. Next, an estimator is developed to online update not only the unmeasured system states but also the total disturbance. Then, the novel adaptive controller, which is composed of the nominal control law and the compensation control law, is designed. Finally, the proposed scheme is evaluated in the SMA experimental setup. The comparison results have demonstrated that the proposed control method can track reference trajectory accurately, reject load variations and stochastic disturbances timely, and exhibit satisfactory robust stability. The proposed control scheme is system independent and has some potential in other types of SMA-actuated systems.

Multibody Dynamic Model of Web Guiding System With Moving Web

2010 ◽  
Vol 132 (5) ◽  
Author(s):  
Lei Yu ◽  
Zhihua Zhao ◽  
Gexue Ren
Keyword(s):  
Dynamic Model ◽  
Lateral Displacement ◽  
Dynamical Behavior ◽  
Contact Forces ◽  
Lagrangian Formulation ◽  
Pi Control ◽  
Control Law ◽  
Reference Surface ◽  
Multibody Dynamic ◽  
Guiding System

In this paper, a multibody dynamic model is established to simulate the dynamics and control of moving web with its guiding system, where the term moving web is used to describe thin materials, which are manufactured and processed in a continuous, flexible strip form. In contrast with available researches based on Eulerian description and beam assumption, webs are described by Lagrangian formulation with the absolute nodal coordinate formulation (ANCF) plate element, which is based on Kirchhoff’s assumptions that material normals to the original reference surface remain straight and normal to the deformed reference surface, and the nonlinear elasticity theory that accounts for large displacement, large rotation, and large deformation. The rollers and guiding mechanism are modeled as rigid bodies. The distributed frictional contact forces between rollers and web are considered by Hertz contact model and are evaluated by Gauss quadrature. The proportional integral (PI) control law for web guiding is also embedded in the multibody model. A series of simulations on a typical web-guide system is carried out using the multibody dynamics approach for web guiding system presented in this study. System dynamical information, for example, lateral displacement, stress distribution, and driving moment for web guiding, are obtained from simulations. Parameter sensitivity analysis illustrates the effect of influence variables and effectiveness of the PI control law for lateral movement control of web that are verified under different gains. The present Lagrangian formulation of web element, i.e., ANCF element, is not only capable of describing the large movement and deformation but also easily adapted to capture the distributed contact forces between web and rollers. The dynamical behavior of the moving web can be accurately described by a small number of ANCF thin plate elements. Simulations carried out in this paper show that the present approach is an effective method to assess the design of web guiding system with easily available desktop computers.

Morphological Adaptation for Speed Control of Pipeline Inspection Gauges MC-PIG

2021 ◽  
Author(s):  
Sujet Phodapol ◽  
Tachadol Suthisomboon ◽  
Pong Kosanunt ◽  
Ravipas Vongasemjit ◽  
Petch Janbanjong ◽  
...  
Keyword(s):  
Fluid Velocity ◽  
Operating Conditions ◽  
Pi Control ◽  
Operating Pressure ◽  
Acceptable Error ◽  
Valve Unit ◽  
Pipeline Inspection ◽  
Flow Adjustment ◽  
Valve Angle ◽  
Moving Speed

Abstract Passive and active hybrid pipeline inspection gauges (PIGs) have been used for in-pipe inspection. While a passive PIG cannot control its speed, the hybrid version can achieve this by using an integrated valve specifically designed and embedded in the PIG. This study proposes a generic new method for speed adaptation in PIGs (called MC-PIG) by introducing a generic, modular, controllable, external valve unit add-on for attaching to existing conventional (passive) PIGs with minimal change. The MC-PIG method is based on the principle of morphological computation with closed-loop control. It is achieved by regulating/computing the PIG's morphology (i.e., a modular rotary valve unit add-on) to control bypass flow. Adjustment of the valve angle can affect the flow rate passing through the PIG, resulting in speed regulation ability. We use numerical simulation with computational fluid dynamics (CFD) to investigate and analyze the speed of a simulated PIG with the valve unit adjusted by proportional-integral (PI) control under various in-pipe pressure conditions. Our simulation experiments are performed under different operating conditions in three pipe sizes (16″, 18″, and 22″ in diameter) to manifest the speed adaptation of the PIG with the modular valve unit add-on and PI control. Our results show that the PIG can effectively perform real-time adaptation (i.e., adjusting its valve angle) to maintain the desired speed. The valve design can be adjusted from 5 degrees (closed valve, resulting in high moving speed) to a maximum of 45 degrees (fully open valve, resulting in low moving speed). The speed of the PIG can be regulated from 0.59 m/s to 3.88 m/s in a 16″ pipe at 4.38 m/s (in-pipe fluid velocity), 2500 kPa (operating pressure), and 62 °C (operating temperature). Finally, the MC-PIG method is validated using a 3D-printed prototype in a 6″ pipe. Through the investigation, we observed that two factors influence speed adaptation; the pressure drop coefficient and friction of the PIG and pipeline. In conclusion, the results from the simulation and prototype show close characteristics with an acceptable error.

Robust active disturbance attenuation control of an uncertain quadrotor

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Nigar Ahmed ◽  
Ajeet kumar Bhatia ◽  
Syed Awais Ali Shah
Keyword(s):  
Control Algorithm ◽  
Sliding Mode ◽  
The State ◽  
Disturbance Attenuation ◽  
State Variables ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Content Type ◽  
Highly Nonlinear ◽  
The Stability

PurposeThe aim of this research is to design a robust active disturbance attenuation control (RADAC) technique combined with an extended high gain observer (EHGO) and low pass filter (LPF).Design/methodology/approachFor designing a RADAC technique, the sliding mode control (SMC) method is used. Since the standard method of SMC exhibits a chattering phenomenon in the controller, a multilayer sliding mode surface is designed for avoiding the chattering. In addition, to attenuate the unwanted uncertainties and disturbances (UUDs), the techniques of EHGO and LPF are deployed. Besides acting as a patch for disturbance attenuation, the EHGO design estimates the state variables. To investigate the stability and effectiveness of the designed control algorithm, the stability analysis followed by the simulation study is presented.FindingsThe major findings include the design of a chattering-free RADAC controller based on the multilayer sliding mode surface. Furthermore, a criterion of integrating the LPF scheme within the EHGO scheme is also developed to attenuate matched and mismatched UUDs.Practical implicationsIn practice, the quadrotor flight is opposed by different kinds of the UUDs. And, the model of the quadrotor is a highly nonlinear underactuated model. Thus, the dynamics of the quadrotor model become more complex and uncertain due to the additional UUDs. Hence, it is necessary to design a robust disturbance attenuation technique with the ability to estimate the state variables and attenuate the UUDs and also achieve the desired control objectives.Originality/valueDesigning control methods to attenuate the disturbances while assuming that the state variables are known is a common practice. However, investigating the uncertain plants with unknown states along with the disturbances is rarely taken in consideration for the control design. Hence, this paper presents a control algorithm to address the issues of the UUDs as well as investigate a criterion to reduce the chattering incurred in the controller due to the standard SMC algorithm.

scholarly journals Adaptive Projective Synchronization between Two Different Fractional-Order Chaotic Systems with Fully Unknown Parameters

2012 ◽  
Vol 2012 ◽  
pp. 1-16 ◽  
Author(s):  
Liping Chen ◽  
Shanbi Wei ◽  
Yi Chai ◽  
Ranchao Wu
Keyword(s):  
Fractional Order ◽  
Chaotic Systems ◽  
Projective Synchronization ◽  
Control Law ◽  
Unknown Parameters ◽  
Chen System ◽  
Fractional Order Differential Equations ◽  
Response Systems ◽  
The Stability ◽  
Adaptive Control Law

Projective synchronization between two different fractional-order chaotic systems with fully unknown parameters for drive and response systems is investigated. On the basis of the stability theory of fractional-order differential equations, a suitable and effective adaptive control law and a parameter update rule for unknown parameters are designed, such that projective synchronization between the fractional-order chaotic Chen system and the fractional-order chaotic Lü system with unknown parameters is achieved. Theoretical analysis and numerical simulations are presented to demonstrate the validity and feasibility of the proposed method.

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