Speed Of Hydraulic Cylinder Research Articles

The Effect of Hydraulic Accumulator on the Performance of Hydraulic System

The purpose of this paper is to depict the effect of adding a hydraulic accumulator to a hydraulic system. The experimental work includes using measuring devices with interface to measure the pressure and the vibration of the system directly by computer so as to show the effect of accumulator graphically for real conditions, also the effects of hydraulic accumulator for different applicationshave been tested. A simulation analysis of the hydraulic control system using MATLAB.R2010b to study was made to study the stability of the system depending on the transfer function, to estimate the effect of adding the accumulator on stability of the system. A physical simulation test was made for the hydraulic system using MATLAB to show the effect of the accumulator when it's connected to the system for different parameters and compare it with a PID controller. The hydraulic system has been simulated and tested using Automation Studio (AS) to measure different data such as the linear speed of hydraulic cylinder and the effect of connecting the accumulator to the system. All the results showed that the hydraulic accumulator has a great benefits and a large enhancement to the hydraulic system.

Design and Experiment of Side-Shift Stubble Avoidance System for No-Till Wheat Seeder Based on Deviation-Perception Fusion Technology

To improve the stubble avoidance rate of no-till wheat seeders under the environment of corn stubble, the side-shift stubble avoidance system was developed in the present study based on deviation-perception fusion technology. Firstly, the amount of implement deviation compensation was accurately obtained by the information sensing system. Then, a fuzzy PID algorithm was proposed to optimize the performance of the control system. Finally, the simulation model of the control system was developed by Matlab/Simulink. The simulation results showed that the regulation time required for the system response curve to reach the steady state was 1.0 s, and the maximum overshoot was 8.2%. To verify the performance of the side-shift stubble avoidance system, an orthogonal test was conducted. The optimal combination of parameters was obtained, including the operation speed of 1.3 m/s, the hydraulic cylinder speed of 25 mm/s, and the straw mulch amount of 1.2 kg/m2. The field verification test was performed under the optimal parameters, showing the stubble avoidance rate was 90.6%, and the mean value of the sowing variation coefficient was 27.12%, which fully satisfied the requirements of stubble avoidance and sowing operation.

Hybrid dynamic optimal tracking control of hydraulic cylinder speed in injection molding industry process

<p style='text-indent:20px;'>Injection speed control is one of the most essential components in the injection molding process. It is critical to implement fast and reliable injection speed optimization control for the effective manufacturing of injection molding products. In this paper, the speed tracking control problem of the hydraulic cylinder of an injection molding machine driven by a typical servo motor is studied. An efficient two-stage optimization framework that leverages the ideas of both control parameterization (CP) and particle swarm optimization (PSO) is proposed for generating the optimal signal input to achieve the required injection speed tracking over a certain time. To this end, the dynamic model of the hydraulic system in the injection molding equipment is firstly established and the optimal controller design problem is transformed into sequential optimal parameter decision problems, and the explicit expressions of the gradient information of the objective function as well as the constraint on the parameters of the decision variables are derived. Then, the PSO combined with the CP and gradient-based algorithm is utilized to to solve the parameters of the controller efficiently. The two-stage optimization framework proposed in this paper can improve the convergence speed of the CP method and the precision of the PSO and easy-to-implement in engineering and industrial deployment. Finally, the feasibility and effectiveness of the proposed design method are verified by experimental simulations.</p>

Adaptive Fuzzy Sliding Mode Control Based on Pi-sigma Fuzzy Neutral Network for Hydraulic Hybrid Control System Using New Hydraulic Transformer

Control issue is the key for applying hydraulic hybrid system, especially for common pressure rail (CPR) system which has the huge potential to enhance efficiency. In the paper, the mathematical model of hydraulic cylinder speed control system using new hydraulic transformer is established. Then an adaptive fuzzy sliding mode controller based on Pi-sigma fuzzy neutral network is designed to solve the problem of parameter uncertainty and nonlinearity without establishing the precise model. Furthermore, compared to PID and conventional adaptive fuzzy system, the controller proposed can achieve good control performance and strong robustness in the presence of time-varying uncertainty.

Improvement of Operation Stability of Hydraulic Cylinder

In the speed control loop of hydraulic system, the unstable speed of hydraulic cylinder and hydraulic impact often occur, which makes the hydraulic machinery unable to work normally. In this paper, the causes of unstable motion of hydraulic cylinder are analysed from the following aspects: the load of throttle speed control loop varies greatly, the pressure difference between front and back of speed control valve is too small, and the hydraulic impact occurs when the speed is changed. Specific improvement methods are put forward.

Experimental and numerical investigation of a strain rate controlled hydraulic bulge test of sheet metal

An exact characterization of the material behavior is required to identify material laws, e.g. yield criteria or isotropic hardening laws, for an accurate numerical design of forming operations. For instance, the hydraulic bulge test is carried out to determine the material behavior under biaxial stretching. In case of strain rate sensitive materials, as aluminum alloys or mild steels, the influence of the strain rate is important and a constant strain rate during the test is necessary for reliable results. In this contribution, a hydraulic bulge test setup is presented, which allows an online detection of the local strain to control the hydraulic pressure for an almost constant strain rate during the test. Moreover, the difference of the material behavior between strain rate controlled bulge tests and bulge tests with commonly used constant hydraulic cylinder speed is investigated for the aluminum alloy AA5182-O, the deep drawing steel DX54 and the advanced high strength steel HCT980X. Additionally, the influence of the hardening behavior on the numerical results of the hydraulic bulge test is exemplarily investigated for AA5182-O.

Simulation and Experimental Study on Coal and Rock Cutting Test Equipment Hydraulic Feed System

In order to control the speed of hydraulic cylinder precisely through a given voltage signal on proportional valve, we adopt the pressure compensator and proportional directional valves throttle circuit in the hydraulic feed system of the designing coal and rock cutting test equipment. The simulation model of the system based on AMESim is built, the dynamic characteristic on the feed system of proportional valve-controlled cylinder’s speed is analyzed, experiments under no-loading condition on the hydraulic pump station is done. Simulation and experimental results show that the cylinder’s speed can be controlled precisely through a given voltage signal on proportional valve, the experimental and simulation results are close, which can better meet the test requirements of coal and rock cutting. Finally the sorting curves of the cylinder’s speed varies with the proportional valve opening can provide the basis of cutting parameters of coal and rock cutting test equipment.

Experimental Research of Hydraulic Cylinder Speed Control System Based on High-Speed On-Off Valve

Series and parallel application schemes between high-speed on-off valve and hydraulic cylinder are proposed to control the speed of hydraulic cylinder based on the analysis of high-speed on-off valve flow characteristics. The duty cycle of pulse control signal was changed according to the displacement of hydraulic cylinder to control the speed of hydraulic cylinder and weak the impact. The speed and acceleration curve of hydraulic cylinder were achieved by the means of experiment with FESTO. Experimental results show that, two application schemes can both control the speed of hydraulic cylinder effectively. Series application scheme can be only applied to small flow hydraulic system; parallel application scheme has wider application.

Analysis of the Opening Characteristic of Hydraulic Control One-Way Valve in Vertical Hydraulic Cylinder Balance Circuits

Hydraulic control one-way valve as the retaining element of vertical hydraulic cylinder, often is due to improper application to produce large opening pressure, not unlocking, vibration, noise etc.fault. This paper analyses two vertical hydraulic balance circuit, one makes use of the one-way throttle valve and another is not,calculates the necessary condition and opening pressure of hydraulic control one-way valve reverse opening, obtains the opening characteristic of hydraulic control one-way valve in vertical balancing circuit, acquires the relationship of the reverse opening pressure with hydraulic cylinder balance pressure, hydraulic cylinder speed ratio, hydraulic control one-way valve structural parameters. Lastly, how to correctly use the hydraulic control one-way valve is discussed in the vertical hydraulic cylinder balanced circuit.

Design of Bypass-Throttle Hydraulic Cylinder Speed Control System Base on High-Speed On-Off Valve

Application of high-speed on-off valve in the hydraulic speed control system was researched in this paper. The bypass-throttle circuit application of high speed on-off valve is proposed to control the speed of hydraulic cylinder. The duty cycle of pulse control signal was changed according to the displacement of hydraulic cylinder to control the speed and weak the impact. The speed and accelerated speed curves of hydraulic cylinder were achieved by the means of simulation with Simulink and experiment with FESTO is obtained, and research result shows that the applied scheme can effectively control the speed of hydraulic cylinder effectively.

Design of Direct-Control Hydraulic Cylinder Speed Control System Base on High-Speed On-Off Valve

Application of high-speed on-off valve in the hydraulic speed control system was researched in this paper. The direct-control circuit application of high speed on-off valve is proposed to control the speed of hydraulic cylinder. The duty cycle of pulse control signal was changed according to the displacement of hydraulic cylinder to control the speed and weak the impact. The speed and accelerated speed curves of hydraulic cylinder were achieved by the means of simulation with Simulink and experiment with FESTO is obtained, and research result shows that the applied scheme can effectively control the speed of hydraulic cylinder effectively.

Design of Hydraulic Cylinder Speed Control System Base on High-Speed on-Off Valve

In order to study the Application of high-speed on-off valve in the hydraulic cylinder speed control system, series and parallel application schemes between high-speed on-off valve and hydraulic cylinder are proposed to control the speed of hydraulic cylinder. The duty cycle of pulse control signal was changed according to the displacement of hydraulic cylinder to control the speed of hydraulic cylinder and weak the impact. The simulation curve compared with the experimental results show that, two application schemes can both control the speed of hydraulic cylinder effectively. Series application scheme can be only applied to small flow hydraulic system; parallel application scheme has wider application.

Modeling and Simulation Research of Hydraulic Cylinder Speed Control System Based on High-Speed On-Off Valve

Application of high-speed on-off valve in the hydraulic cylinder speed control system was researched in this paper. Series and parallel application schemes between high-speed on-off valve and hydraulic cylinder are proposed. Model of high-speed on-off valve and hydraulic circuit were established to carry out simulation. The speed and acceleration curve of hydraulic cylinder were achieved by the means of simulation with Simulink. The simulation curves show that, two application schemes can both control the speed of hydraulic cylinder effectively. Series application scheme can be only applied to small flow hydraulic system; parallel application scheme has wider application.

Research on the Application of High Speed on Off Valve in the Hydraulic Cylinder Speed Control System

An application of high speed on-off valve which is connected between rod cavity and no-stem cavity of hydraulic cylinder was designed to study the speed control problem when the motion state of hydraulic cylinder is transformed. Research result shows that HSV can reduce the maximum starting acceleration and the final velocity effectively, and can realize the speed control when the motion state of hydraulic cylinder is transformed.

Design of an Experimental Platform for Hydraulic Servo System

VRLA (valve-regulated lead-acid) and Pump-control are the two kinds of power components for hydraulic servo system. With different command device, feedback measurement device and different corresponding electronic components, the hydraulic servo systems are different. To ensure maximum performance of the whole device, the overall design (including mechanical, electrical design) should be considered for hydraulic servo system. Machinery-electric-hydraulic should be in coordination with each other. The hydraulic system components are used to change the speed of hydraulic cylinder and alter direction of hydraulic cylinder and hydraulic motor. The solenoid valve for motor and hydraulic servo system and the control of pressure relay can implement by the electric section.

Integrierbare Positions- und Geschwindigkeitssensoren für die Mobilhydraulik

In recent years the use of electrically or electronically activated proportional valves in mobile hydraulics has grown significantly, and has initiated an accelerated trend towards the implementation of controllable hydraulic drives in agricultural machines. Hydraulic actuators with integrated sensors, which make it possible to utilise electronic control systems, are a good example of this. In this paper the integrated determination of current position and hydrau-lic cylinder speed through sensors is presented, through which partially automated functions, like electro-hydraulic parallel lifting systems for an agricultural front-end loader can be achieved.