Telescopic Cylinder Research Articles

Analysis and Optimization of Telescopic Drill Rod Structure Based on SolidWorks

In this paper, the structural performance of the telescopic drill pipe structure is optimized and analyzed. The main working principle of the telescopic drill pipe is to drive the two internal telescopic rods through the two-stage telescopic cylinder, so that it can produce stable reasoning and motion characteristics. The 3D model of the telescopic drill pipe is also established by using SolidWorks software. The simulation of SolidWorks module is used to analyze the dynamic characteristics of the two-stage telescopic drill pipe, including the first five modal shapes, static stress and fatigue life of the structure. The distribution law of the maximum stress distribution point and the easily damaged position is found, and the structural design is optimized, which provides a reliable structural design scheme for improving the fatigue strength of the telescopic rod and prolonging the life cycle of the equipment.

A Study on the Optimal Grasping Angle Algorithm for Plug Seedlings Based on Machine Vision

During the replanting operation of a seedling tray, the end-effector needs to repeatedly grab the qualified plug seedlings in the supply tray and release them to the target tray for replanting, and in the process of grasping, the end-effector may cause some mechanical damage to the plug seedlings, thus affecting their quality. Therefore, in order to be able to adjust the position of the hand claw grasping point according to the morphological characteristics of the plug seedlings and select the optimal grasping point, this paper proposes research on the optimal grasping angle algorithm for plug seedlings based on machine vision. Firstly, a rotatable three-jaw end-effector is designed, which uses a three-jaw structure for grasping the burrowing seedlings. The three claws are driven with a telescopic cylinder to carry out clamping and relaxing actions. The rotation of the three claws is controlled with the stepper motor to adjust the optimal grasping position. Secondly, based on the pre-processing of an image of the hole tray seedling, the extraction of feature points in the region of interest, and the calculation of localization, the angle between the angular bisector of the cotyledon leaf blade of the hole tray seedling and the horizontal positive direction is solved. In this paper, two methods are designed to calculate the coordinates of feature points: one is the geometric method and the other is the center-of-mass method. Finally, the optimal grasping angle is calculated by analyzing the angle between the angular bisector of the cotyledon leaf blade and the horizontal positive direction of the cavity seedlings. According to the test, the average calculation error of the proposed algorithm is 3.12 degrees, and the average calculation time is 0.512 sec/sheet, which meet the requirements of the replanting operation.

Neural Network-Based Dual-Cylinder Synchronous Control of a Multi-Link Erection Mechanism

A dual-cylinder erection mechanism, in which two telescopic cylinders physically connect to a load, is a nonlinear system with model uncertainties and coupled dynamics. In this paper, a novel synchronous control algorithm with thrust-allocation law is proposed for eliminating the excessive internal forces caused by the unbalanced rotation and lateral moments during the erection process. With regulated internal forces, the “pull and drag” issue is attenuated and better synchronization performance is attained. For improved tracking accuracy, the inter-stage collision dynamics of the telescopic cylinder are considered for model compensation to enhance stage-changing and in-position performance. A radial basis function (RBF) neural network is utilized to estimate the model uncertainties and external disturbances, which alleviates reliance upon the accuracy of a system model for controller implementation. As a result, theoretical analysis revealed that the semi-global asymptotic stability and synchronized motion performance with decreased internal forces can be achieved via the presented synchronous controller with thrust-allocation strategy. Contrasting simulations were implemented on a multi-link erection mechanism and the results confirmed the superiority and effectiveness of the proposed synchronous control algorithm.

Modeling and simulation of electro-hydraulic telescopic elevator system controlled by programmable logic controller

Traditional hydraulic <span>cylinders are widely used in industry as load lifting tools. There is difficulty in employing these cylinders in narrow installation space like building elevators as well as they require a long working stroke, so solving this problem requires using the telescopic hydraulic cylinder instead. This cylinder is a unique hydraulic cylinder design that uses a sequence of decreasing diameters to create a long operating stroke in a compact-retracted form. In this work, the Auto Station software is used to build a telescopic hydraulic cylinder model that includes hydraulic elements such as double-acting hydraulic telescopic cylinders, pump, valves, pipeline, and filter, as well as electrical parts such as programmable logic controller (PLC), push-bottoms, and position sensors. The proposed model is operated by a PLC controller and has three floors with an overall height of around 300 cm for lifting a 100 kg payload. The accuracy and validity of this model in lifting big weights were demonstrated by the analytical findings of characteristic curves for cylinder position and velocity. This model can be used a basic reference to analyze and construct hydraulic cylinders with any number of stages. The findings of simulations reveal that a quick change in pressure due to phase change causes multi-phase vibration.</span>

A study on the applications of vibratory motor for material handling vehicles

This work aims at improving the efficiency and safety of the tipper trucks while in action. This project focused on performing a detailed analysis of the performance, safety, and cost aspects of the present techniques of achieving that. The pros and cons of incorporating a vibrator for the tipper truck are studied. This involved extensive FEA analysis in the preliminary stage. The structural, vibrational, and fatigue analysis is done for the critical components which helped in deciding the feasibility of incorporating such a mechanism. The critical components for the analysis are the base of the truck body, trunnion, brackets for mounting the telescopic cylinder, and the vibratory motor. The CAD models are prepared according to the industry standards and analyses are performed. Random data for forced vibration is generated, which is used to perform analyses on the components in FEA. Experimentation on a scaled-down model is also conducted to get the real-time data for the system. A vibration sensor would be incorporated using Arduino, and the acceleration data of vibration are recorded and compared by the theoretical values. A comparative study for the stability analysis is done, with and without the vibrator. A detailed report for the change in stroke length, pump pressure/flow requirement, etc. is formed and compared. The improvement in efficiency of dumping, time-saving and various other parameters is also considered. The cost aspect of rolling this system in the market is also studied.

Development and evaluation of a pneumatic finger-like end-effector for cherry tomato harvesting robot in greenhouse

This paper presents the development and evaluation of a pneumatic finger-like end-effector for cherry tomato harvesting robot. The end-effector is pneumatically controlled and has the capability of picking cherry tomatoes continuously and steadily. The end-effector is compact in overall structure, which consists of finger-like clamping finger, rotating and telescopic cylinders, and RGB-D camera, etc. Another important feature is that the clamping finger uses a combination of clamping and rotating and has good adaptability in dense operating environments. Further, a hand-picking dynamic measurement system is developed to measure and analyze the applied force and disturbance for simplified picking methods during picking. The hand-picking test shows that both the applied force and the disturbance are smaller for rotating compared to pulling, so the method of rotating is chosen for the design of the end-effector in this study. The field test shows the average cycle time of picking single cherry tomato is 6.4 s. The harvest success rates for pickable cherry tomatoes in different directions are 84% (right), 83.3% (back), 79.8% (left), and 69.4% (front), respectively. The failure cases are analyzed and collision and localization failure are the main causes of unsuccessful picking during picking.

Modeling and Simulation of Telescopic Hydraulic for Elevating Purposes

The hydraulic cylinder is widely used in industry as the load lifting structures. A telescopic hydraulic cylinder is a special design of a cylinder with a series of gradually smaller diameter tubes overlapping each other. Three-stage telescopic cylinder performance analysis is performed with the help of the Finite Element Method. Also, MATLAB Simulink is used to create a complete design of the dynamic model of the telescopic cylinder. The analysis results of characteristic curves for telescopic cylinder position, velocity, and acceleration show the simulation model's accuracy and plausibility. This package will provide a basic reference for analyzing and designing the hydraulic cylinders with any number of stages. Simulation results show that a sudden change of pressure upon phase change will lead to multi-phase vibration.

An analytical approach to evaluate the maximum load carrying capacity for pin-mounted telescopic hydraulic cylinder

The hydraulic cylinder is an actuating mechanical maneuver used to transfer the power from one station to another. For industrial purposes, various types of cylinders are employed as per the requirement. Telescopic hydraulic cylinder, also known as the two-stage hydraulic cylinder is one of the widely used hydraulic cylinders in the industry. The closed center length of a telescopic cylinder is 20% to 40% of the open center length depending on the number of stages. The safe operation of such telescopic hydraulic cylinder is highly essential. One of the prominent failures includes the buckling failure of the hydraulic cylinder. Once the system fails, the operating parameters change abruptly and thus the proper working gets affected. In literature, there is no significant standard that governs the buckling load determination of two-stage hydraulic cylinder. Existing technical standard ISO/TS 13725 : 2016 approach is only prescribed for the single-stage cylinder. In this manuscript, the emphasis is kept upon the determination of the buckling load for the two-stage pin-mounted telescopic hydraulic cylinder. The buckling governing equation has been derived to obtain the buckling load using an analytical approach. Additionally, the stress condition of cylinder barrels of different stages has been discussed per thick cylinder theory. The finite element analysis has been performed for various dimensions of the hydraulic cylinder. The results obtained from analytical results show close vicinity with the finite element results.

Buckling load for telescopic cylinder using successive approximation method

In this manuscript, a new way of determining the buckling load of the two-stage both end-hinged, single acting hydraulic cylinder has been engrossed using successive approximation method. The method has been extended from single stage hydraulic cylinder to the two-stage hydraulic cylinder mounted with pin support at both ends. This method includes a few numbers of iterations required in order to achieve good accuracy or in other words getting the minimum error. Further, finite element analysis of the hydraulic cylinder has also been performed for the validation purpose. The buckling mode shape for three different modes and their corresponding buckling load has also been obtained using the finite element method. The approximation of the buckling load corresponding to the first buckling mode shape has been performed and observed load lies in the close vicinity of theoretical calculation. The critical load obtained using a successive approximation method after two iteration shows the minor deviation of 3.63%.

Telescopic Hydraulic Cylinder Made of Composite Material

The aim of this research is to design a telescopic hydraulic cylinder, normally used in industrial filed, made of different materials and in particular composite material instead of classical structural steel. Specifically it will refer to the application of this actuator on a dump truck and designated to the transport of soil material, starting from hard load conditions and from the minimum incline to guarantee the complete emptying of the dump truck, the geometry of the cylinder has been defined. The peculiarity of this research is about the materials employed for the design, and the future fulfilment of this component. The work deal with the custom of 4 different materials, or rather: 2 type of steel (structural: S235 JR and stainless AISI 304), aluminum alloy 7075-T6 (Ergal) and a composite material made of epoxy resin and carbon fibers. The elaboration of the new solutions presented, has been realized evaluating the barrel of the cylinder as a container in a pressure vessel with thin walled, whereas the rod as a beam prone to buckling. Is possible to observe how the study has been faced also with the aid of analysis about finite elements, as well as to verify the design of the component, also to prove others phenomena, as the instability for peak load. Moreover is possible to highlight that the adopted theory for the planning of composite barrel, despite load conditions are the same, they differs from the theory used for aluminum and steel because of his anisotropic behavior. Given the particular nature of the composite material, the arguments related with technology are set out, about technology production through filament winding and the assembly of the components of the telescopic cylinder. Thanks to the achieved results, is possible to observe how the use of the composite material, for the realization of that component, can be extremely favorable for the weight achieving a reduction of the 96% starting from 5537 N, reaching 196 N.

Stability of a hydraulic telescopic cylinder subjected to generalised load by a force directed towards the positive pole

The paper presents the boundary problem of the stability of a telescopic hydraulic cylinder subjected to a generalized load with a force directed to the positive pole. The boundary problem was formulated on the basis of the Hamilton principle. Numerical calculations were carried out, taking into account the influence of the parameters of the load heads (radii of loading and receiving head, length of bolt). On the basis of the numerical calculations, regions of load heads parameters were presented, at which the load bearing capacity of the analysed telescopic hydraulic cylinder is the largest from the buckling standpoint.

Mechanical Model of Drilling Robot Driven by the Differential Pressure of Drilling Fluid

A new type of drilling robot driven by drilling fluid is proposed, whose traction force is provided by differential pressure inside and outside of the drilling robot. The fluid mechanical model of differential pressure is established based on the principle of pressure drop. The equations for calculating the traction force of the robot in no-load condition and load condition are derived respectively. The dynamic model of drilling robot is established and the calculation method of key parameters such as weight on bit (WOB) and rate of penetration (ROP) in the dynamic model is derived. The influence of flow rate of drilling fluid on ROP/velocity and traction force of the drilling robot is analyzed. Among them, with the increasing of flow rate, the ROP/velocity and the traction force of drilling robot increases in a nearly linear trend. In the no-load condition (traction process), the drilling robot will be in acceleration until the telescopic cylinder stops pumping drilling fluid. In the load condition (drilling process), the drilling robot will reach a balance with the mechanical drilling rate within 0.1s. The proposed drilling robot can provide the possibility for the downhole operations in horizontal well with long displacement or in the condition of large traction force request. What’s more, this paper will provide a theoretical guidance for the control of ROP and WOB in the drilling process, and promote the application of drilling robots.

Effect of Internal Clearance on Buckling of Multistage Hydraulic Cylinder

Multistage cylinders are generally used to lift and tilt heavy loads under controlled speed. In defence applications multistage cylinders are used in missile tilt platform and antenna mast. Earth moving equipment’s such as tippers, dumpers, cranes and compactors uses multistage cylinders for operations. In the present work multistage hydraulic cylinder (telescopic cylinder) with three stage has been analysed using strain energy method and verified with finite element analysis. The research work investigates the effect of internal clearances which reduces the critical buckling load of hydraulic cylinders. The results are validated by buckling load test. The clearances between the tube to piston guides, gland guide to piston rod, clearances due to tube expansion under pressure, initial curvature in the tube, eccentricity of cylinder components and tube ovality are considered in the buckling load test. Describes the comparative study of buckling load tests of three stage hydraulic cylinders having fixed free and hinged mounting with five different internal clearances.<br /><br />

Mathematical modelling and backstepping adaptive sliding mode control for multi-stage hydraulic cylinder

Multi-stage hydraulic cylinder is widely used in large scale erecting devices. It can provide longer stroke from an initial package than single stage cylinder. It is divided into telescopic type and synchronous type. However, its structure is complicated. In order to get the characteristics of multi-stage hydraulic cylinder, motion model was established based on node chamber method. The LuGre friction model was improved considering the lubricant film. The contact force model was optimised using the equivalent damping model of the hysteresis factor. Simulations of erection process driven by telescopic and synchronous hydraulic cylinder were completed. Backstepping adaptive sliding mode controller was designed for multi-stage hydraulic cylinder. The proposed controller has a better performance compared to PID controller and ordinary sliding mode controller. The chattering has been reduced by using the saturation function instead of the sign function.

Simulation and Experimental Research on the Telescopic Cylinder Controlling of Socketed Rotary Reaming Device for Rotary Drilling Rig

Simulation and Experimental Research on the Telescopic Cylinder Controlling of Socketed Rotary Reaming Device for Rotary Drilling Rig

Multi-criteria decision analysis to select the optimum position and proper field of view of a photosensor

The lack of knowledge concerning the commissioning of a daylight responsive system constitutes a serious impediment to their widespread use. Furthermore, installation details and tools regarding their photosensor position and field of view (FOV) are insufficient. This paper presents a decision making method capable to estimate the best position of a photosensor on the ceiling and its proper FOV based on multiple criteria analysis. The criteria used are (a) the correlation of the lighting levels between the working plane and the ceiling, (b) the corresponding energy savings and (c) the lighting adequacy which is defined as the percentage for occupied time with total illuminance exceeding design illuminance (i.e 500lux EN 12464-1, 2011) and is strongly affected by the control algorithm.A number of simulations with variable FOV and position of photosensors were performed in order to clarify the calculation procedure of the proposed methodology. Three different typical room geometries have been used with variable window sizes and orientation. Furthermore a prototype photosensor with variable FOV through the use of a telescopic cylinder was constructed and placed in a scale room (1:10) in order to verify the results of simulations. The verification was based on a set of experimental procedures concerning measurements of the spatial response of the prototype photosensor (for various FOVs) and measurements of ceiling/workplane illuminance inside the scaled room for various combinations of position and FOV of the photosensor. The proposed methodology can be used as a tool for the determination of the optimum operation of a daylight responsive system with photosensors.

Accurate Calculation about Euler Critical Force of Multistep Telescopic Cylinder with Two Different Kinds Support Conditions

Variable cross-section telescopic cylinder is the frenquently-used member being loaded, which the buckling critical force is variable as the boundary and load condition changed. According to two common boundary supprot conditions, this paper established the deflection differential equations of arbitrary multistep telescopic boom by vertical and horizontal bending theory with second-order effect, introduced the boundary condition and deformation compatibility condition, obtained the recurrence expression of buckling characteristic equations, and some practical applications were presented. Took certain four-sectioned telescopic cylinder as example, calculated the buckling critical force by the method and compared the results with ANSYS, the accuracy of the buckling characteristic equations deduced in this paper were verified.

On the Buckling Behaviour of Telescopic Hydraulic Cylinders

Telescopic cylinders are generally employed as linear actuators, when the desired moving span is several times the length of the closed device, like in cargo trucks lifting applications, for instance. During the active phase of the actuation, hydraulic power is normally used to feed pressu-rized fluid inside the cylinder, thus providing the progressive extension of the cylinder ele-ments and the required operative axial thrust. In this condition, therefore, cylinders must bear external compressive loadings in an increasingly slenderness configuration, which can give rise to buckling failures. In this study, experimental measurements of the limiting axial loadings of telescopic cylind-ers, in full extended conditions, have been performed both in laboratory and during real oper-ations on the field. The strains of the material in the critical sections and the lateral deflec-tions of the tested structures have been recorded as a function of the applied loads. The re-sults of this investigation are presented and discussed, in order to identify the signals of inci-pient buckling and find out the ultimate load carrying capabilities of this kind of components.

Slenderness ratio of telescopic cylinder-columns

The present paper deals with the effective slenderness ratio of telescopic cylinders as a long column having different cross sections. Firstly, the slenderness ratio defined in the current standard for the telescopic cylinders is discussed to point out some difficulties which arise when the ratio is applied to the column having different cross sections. Secondly, a new effective slenderness ratio is proposed for columns having different cross sections by introducing a partial effective slenderness ratio. Finally, the proposed slenderness ratio is applied, for extending and development of discussion, to a two-staged column having piece-wise constant cross sections and a cylindrical column having linearly varying diameters.

Characterization of triological sealing system components using scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS)

A system approach to solving the tribological problems associated with sealing joints implies comprehensive investigation of all the components. To recognize the root cause of any problem and formulate the required performance for extended reliability we have to evaluate any changes in the system as quantitatively as possible. Any measurable parameters, including geometry, density (porosity), hardness distributions, microstructure and grain size changes observed during routine metallurgical analysis could provide evidence of the root cause of failure. In the head-gasket-block sealing system of the internal combustion engine, the EDS evaluation of the chlorine and sulfur distribution through the head gasket flange fracture in conjunction with analysis of the sludge between the head, block and gasket surfaces pointed to the corrosive nature of the gasket flange cracking.This approach is even more useful for the closed tribological system of telescopic hydraulic cylinders or rotary axle shaft oil seals.