International Journal of Fluid Power最新文献

{"title":"Fault Analysis and Diagnosis of Downhole Traction Robot Hydraulic System","authors":"Delei Fang, Yong Xue, Guofeng Jia, Pan Li, Jie Tang, Xiaoming Wang","doi":"10.13052/ijfp1439-9776.2435","DOIUrl":"https://doi.org/10.13052/ijfp1439-9776.2435","url":null,"abstract":"Fault diagnosis of downhole traction robot has characteristics of special mechanical structure, complicated working condition and lack of research data. In this paper, a method of fault analysis and diagnosis of tractor hydraulic system based on model is presented. The failure mode and mechanism of key components in telescopic hydraulic system are analyzed. The fault diagnosis of hydraulic system is proposed based on the mathematical model of hydraulic component. Based on AMESim, the fault model of hydraulic system is established, and the diagnosis of single fault and multi-fault are simulated, which can collect the fault data and the specific diagnosis process. To carry forward the engineering application, the simulated internal leakage system in cylinder is set up and schemes of fault diagnosis are carried out, which prove that the diagnosis is consistent with theoretical analysis and simulation. The research on fault analysis and diagnosis of the downhole traction robot hydraulic system not only lays theoretical basis for the tractor fault detection, but also provides guidance for the construction and implementation of the diagnostic system.","PeriodicalId":13977,"journal":{"name":"International Journal of Fluid Power","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47710916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on Hydro-pneumatic Suspension Test Bench Based on Electro-hydraulic Proportional Control","authors":"Xin Bai, L. Lu, Meng Sun, Leilei Zhao, Hui Li","doi":"10.13052/ijfp1439-9776.2436","DOIUrl":"https://doi.org/10.13052/ijfp1439-9776.2436","url":null,"abstract":"Compared with the traditional automotive suspension, hydro-pneumatic suspension has the characteristics of large energy storage ratio, nonlinear stiffness and can change the ground clearance of the vehicle body, which makes the vehicle have good ride comfort and handling stability during driving. In order to improve the performance of hydro-pneumatic suspension, it is necessary to design hydro-pneumatic suspension test bench for performance test. Aiming at the problem that the output signal of the mechanical test bench used in China is single and has large error, which is difficult to meet the performance test requirements of hydro-pneumatic suspension, a hydro-pneumatic suspension test bench based on electro-hydraulic proportional control is designed. Through AMESim/MATLAB joint system modeling and simulation, in the tracking comparison of sinusoidal signal, compared with the traditional PID control method, the fuzzy PID control method reduces the error by 56.8% and the lag time by 70%; Through the experimental analysis of hydro-pneumatic suspension elastic force characteristic diagram, indicator diagram and damping force velocity characteristic diagram, the error rate of the test bench in sinusoidal signal tracking experiment is less than 15%, which meets the test requirements of hydro-pneumatic suspension.","PeriodicalId":13977,"journal":{"name":"International Journal of Fluid Power","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44624827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Viable Energy Recovery Strategies Through Advanced Directional Control Valve","authors":"Gianluca Ganassi, Davide Mesturini, Cesare Dolcin, Antonella Bonavolontà, E. Frosina, P. Marani","doi":"10.13052/ijfp1439-9776.2428","DOIUrl":"https://doi.org/10.13052/ijfp1439-9776.2428","url":null,"abstract":"The demand for more efficient machines is pushing hydraulic manufacturers to develop a new generation of systems capable of energy saving and recovering. An advanced flow sharing directional control valve with downstream compensation reduces meter-out pressure losses and recovers energy both in combined movements and with overrunning loads. Tests carried out on a prototype on a test bench confirm the proper functioning of the concept and allow tuning its lumped parameters numerical model. A control strategy based on keeping the optimal compensator position allows computing the maximum theoretical recovery. The simulation of a mini-excavator digging cycle shows the energy saving and recovery compared to a standard flow sharing system.","PeriodicalId":13977,"journal":{"name":"International Journal of Fluid Power","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44766078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating the Design Parameters’ Influence in a Fast Switching Valve – An Approach to Simplify the Design Process","authors":"H. Pedersen, N. C. Bender, T. Andersen","doi":"10.13052/ijfp1439-9776.2424","DOIUrl":"https://doi.org/10.13052/ijfp1439-9776.2424","url":null,"abstract":"Designing Fast Switching Valves (FSVs) for digital displacement units is a complicated process pushing the technology to the limit. The system dynamics and the interaction of the fluid, mechanical structure, actuator and control hence calls for advanced modelling, including CFD and FEA, to capture, e.g. fluid stiction effects, end-damping and impact contact stresses. Unfortunately, this essentially renders optimization processes infeasible due to the computational burden involved, although this is precisely what is required for this type of complex multi-domain problem.\u0000Therefore, the focus of the current article is on how a complex mechatronic design problem, like designing an FSV, may be aided by considering decomposing and simplification through sensitivity analysis and analyzing correlations between the design and output parameters. This is done to significantly reduce the original design problem without compromising the investigated design space. The paper focuses specifically on the results related to an FSV and the flow delivering part of this, showing the influence of the various design parameters. However, the approach and considerations may be generalized to an other areas as well.","PeriodicalId":13977,"journal":{"name":"International Journal of Fluid Power","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45248418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-objective Design Optimization and Control Strategy for Digital Hydraulically Driven Knee Exoskeleton","authors":"Rituraj, R. Scheidl","doi":"10.13052/ijfp1439-9776.2425","DOIUrl":"https://doi.org/10.13052/ijfp1439-9776.2425","url":null,"abstract":"This article presents a multi-objective design optimization strategy to determine an optimal design of digital hydraulically driven knee exoskeleton. To satisfy the overall goal of compact and lightweight design, four key design objectives are defined. Via genetic algorithm based multi-objective optimization technique, the pareto-optimal set of designs is determined and the trade-offs between the design objectives are analysed. Via decisions based on component availability and user-comfort, the dimensionality of the pareto-front is reduced to two and an exoskeleton design is selected that offers a good compromise between the design objectives.\u0000For the actuation of the exoskeleton, an energy efficient control strategy is proposed which consists of using passive control during the stance phase and simplified model predictive control during the swing phase. The operation of the chosen knee exoskeleton design and the control strategy is investigated via numerical simulations. The results indicate that the exoskeleton successfully tracks the desired knee motion and delivers the required knee torque.","PeriodicalId":13977,"journal":{"name":"International Journal of Fluid Power","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49214752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Theoretical and Experimental Analysis of a Non Contacting Elastohydrodynamic Sealing","authors":"M. Scherrer, R. Scheidl","doi":"10.13052/ijfp1439-9776.2421","DOIUrl":"https://doi.org/10.13052/ijfp1439-9776.2421","url":null,"abstract":"This paper presents a novel elastohydrodynamic sealing concept for the contactless sealing of spool valves. The basic goal is that the spool and the sleeve can be manufactured with standard mechanical engineering precision. High initial gaps are compensated for the elastic deformation of an elastomer seal driven by a self-regulating hydrodynamic effect. The final gap reveals a small leakage within the range normal for precisely manufactured spool valves and also features a low friction since a direct, solid contact between the seal and the sleeve is prevented. This sought-after behavior in ideal conditions is compared with imperfect situations by means of a simulation study and experiments. The simulation uses a Finite Element model which takes the seal‘s elastic deformation, the mechanical contact, the sealing gap pressure and the surface roughness into account. A simple prototype of the sealing system was produced to test its functionality in real conditions. Leakages of QLeak <= 18 ml/min @180 bar were recorded. However, an unexpectedly high friction occurred indicating an actual contact between the seal and the sleeve. The component roughness was identified as the cause of this behavior.","PeriodicalId":13977,"journal":{"name":"International Journal of Fluid Power","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42850491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Condition Monitoring of an Axial Piston Pump on a Mini Excavator","authors":"Nathan Keller, A. Sciancalepore, A. Vacca","doi":"10.13052/ijfp1439-9776.2422","DOIUrl":"https://doi.org/10.13052/ijfp1439-9776.2422","url":null,"abstract":"The focus of this paper is to show the process of developing a condition monitoring system for an axial piston pump mounted on a mini excavator. This work outlines some previous condition monitoring work on axial piston pumps but addresses the lack of research conducted on mobile hydraulics. The valve plate of the pump is chosen as a case study to demonstrate varying degrees of wear and damage to represent healthy and faulty pump conditions. The wear and damage of these valve plates is measured using an optical profilometer, and efficiency measurements were conducted to characterize the fault levels. Once the faults were characterized, the mini excavator was introduced and instrumented to demonstrate what parameters were being considered. Next, three duty cycles were introduced: controlled, digging, and different operator cycles. The controlled cycles are a very repeatable condition that eliminated the need of an operator. The digging cycle was more of a realistic cycle where an operator dug into a loose pile of soil. The different operator cycle is the same as the digging cycle, but a different operator was employed. The sensors that proved to be the most useful in detecting valve plate faults were the drain pressure, pump port pressures, engine speed, and pump displacement. Fault detectability accuracies of 100% were achievable under the controlled cycle utilizing the Fine KNN classification machine learning algorithm. The digging cycle could achieve a fault detection accuracy of 93.6% using the same algorithm and sensors. Finally, the cross-compatibility between a model trained under once cycle and using data from another cycle as an input was investigated. This study showed that a model trained under the controlled duty cycle does not give reliable and accurate fault detectability for data run in a digging cycle, below 60% accuracies. However, cross-compatibility may be achievable if more extreme faults are present. This work concluded by recommending a diagnostic function for mobile machines to perform a preprogrammed operation to reliably and accurately detect pump faults.","PeriodicalId":13977,"journal":{"name":"International Journal of Fluid Power","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47064447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Deep Reinforcement Learning Control of an Inverted Hydraulic Pendulum","authors":"Faras Brumand-Poor, Lovis Kauderer, G. Matthiesen, K. Schmitz","doi":"10.13052/ijfp1439-9776.2429","DOIUrl":"https://doi.org/10.13052/ijfp1439-9776.2429","url":null,"abstract":"Deep reinforcement learning (RL) control is an emerging branch of machine learning focusing on data-driven solutions to complex nonlinear optimal control problems by trial-and-error learning. This study aims to apply deep reinforcement learning control to a hydromechanical system. The investigated system is an inverted pendulum on a cart with a hydraulic drive. The focus lies on implementing a comprehensive framework for the deep RL controller, which allows for training a control strategy in simulation and solving the tasks of swinging the pendulum up and balancing it. The RL controller can solve these challenges successfully; therefore, reinforcement learning presents a possibility for novel data-driven control approaches for hydromechanical systems.","PeriodicalId":13977,"journal":{"name":"International Journal of Fluid Power","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49039491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Classification and Review of Variable Displacement Fluid Power Pumps and Motors","authors":"Samuel Kärnell, Liselott Ericson","doi":"10.13052/ijfp1439-9776.2423","DOIUrl":"https://doi.org/10.13052/ijfp1439-9776.2423","url":null,"abstract":"Displacement control of positive displacement machines has been a part of fluid power since the early days. Some of the early hydraulic presses already used two different displacement settings, though this was realised by using two different pumps rather than changing the displacement. Later, radial motors with variable stroke length appeared, followed by other designs of variable machines, such as swashplate machines, bent-axis machines, and variable vane machines. All these solutions control the displacement by varying the volume difference of the displacement element – but there are other ways of achieving this. Most have not passed the research state, but some are commercially available. In this paper, different ways of varying the displacement are presented and classified. The classification divides concepts into either control of displaced fluid or control of usage of displaced fluid. In turn, these concepts can be either on system level or displacement element level. This results in four main classes, which to some extent can describe the characteristics of the control.","PeriodicalId":13977,"journal":{"name":"International Journal of Fluid Power","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41382100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Novel Method for the Numerical Investigation of Pendulum Slider Pumps","authors":"Umberto Stuppioni, N. Casari, F. Monterosso, A. Blum, D. Gambetti, M. Pinelli, A. Suman","doi":"10.13052/ijfp1439-9776.2426","DOIUrl":"https://doi.org/10.13052/ijfp1439-9776.2426","url":null,"abstract":"Inadequate lubrication might lead to high friction and wear and can ultimately translate in a higher dissipation of energy, initiation and propagation of fracture and material fatigue. These occurrences are avoided or delayed thanks to an efficient lubricating system. The core of a reliable system is the hydraulic pump which, in the automotive field, is also responsible for power transmission and cooling. Given the importance of such components, improving reliability and performance of the pumps is a topic that is greatly pursued by manufacturers. A machine that is infrequently addressed in the open literature of the fluid power field is the pendulum slider pump. This kind of machine has the makings of high durability performance, short response time, and significant ability to withstand flow contamination by solid particles. Considering the available literature, no Computational Fluid Dynamics (CFD) studies have been presented so far. Among the complexities that hindered the application of CFD to this machine, motion complexity and narrow gaps make the development of a numerical algorithm for its modelling non-straightforward.\u0000In this work, the authors present the development and the application of a CFD model for the simulation of pendulum slider pumps. The structured mesh generation process has been successfully applied to a state-of-the-art pendulum slider pump for automotive applications, and the outcome of the numerical investigation has been validated against an on-purpose built test bench. The results both in terms of variable displacement and fixed displacement behaviour are shown. This work proofs the suitability of the developed model for the analysis of hydraulic pendulum slider pumps.","PeriodicalId":13977,"journal":{"name":"International Journal of Fluid Power","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42297641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}