BATH/ASME 2018 Symposium on Fluid Power and Motion Control最新文献

{"title":"Model-Based Control of a Digital Hydraulic Transformer-Based Hybrid Actuator","authors":"M. Linjama","doi":"10.1115/FPMC2018-8866","DOIUrl":"https://doi.org/10.1115/FPMC2018-8866","url":null,"abstract":"Energy-efficient motion control of hydraulic actuators is a challenging task. Throttle-free solutions have the potential for high efficiency. The main throttle-free approaches are pump-controlled systems, transformer-based solutions, and digital hydraulic solutions, such as switching transformers, multi-chamber cylinder and multi-pressure systems. This paper presents a novel solution based on a so-called digital hydraulic power management system (DHPMS). The DHPMS is freely rotating and a hydraulic accumulator is used for energy storage. In contrast to existing approaches, each actuator has its own DHPMS and a small accumulator to locally handle the power peaks. Only an average amount of power is needed from the hydraulic grid, radically reducing the size of the supply pump and the hydraulic piping and hosing. Pump flow is only 12.5% of the peak flow of the actuator in the case studied. Control of this type of system is challenging, and the model-based approach is used. The controller uses a simplified model and functionality is verified by using a detailed simulation model of the system. The results show that the approach is feasible but is demanding on the control valves. The system delay is also relatively long, which reduces the control performance in high-end systems. Nevertheless, this approach has potential in mobile machines, for example.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115879383","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":"Water Vapour Cavitation in Hydraulic Fluids","authors":"Filipp Kratschun, Tobias Mielke, K. Schmitz","doi":"10.1115/FPMC2018-8872","DOIUrl":"https://doi.org/10.1115/FPMC2018-8872","url":null,"abstract":"Cavitation in hydraulic systems leads to cavitation erosion which ultimately results in system failure [1, 2] and the reduction of the systems’ stiffness. There are three types of cavitation known: gas, vapour and pseudo cavitation [3].\u0000 In previous gas-cavitation studies enormous air release rates in hydraulic fluids have been discovered which could not be explained just by the diffusion of dissolved air through bubble’s boundary. A possible explanation is the simultaneous occurrence of vapour cavitation in conjunction with gas-cavitation. However, this requires drastic pressure drops below several Pa, which is hard to achieve in hydraulic systems.\u0000 This article introduces a further hypothesis for the unexplainable air release rates as fourth type of cavitation. Technical fluids can dissolve other fluids, such as water, to a degree which evaporate at much higher pressures compared to the base fluid.\u0000 Based on a standard HLP 46 hydraulic oil and water as dissolved fluid, the presented hypothesis is verified. Firstly, a phenomenological mathematical model is developed. Subsequently, a test rig is presented to prove the hypothesis.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126578906","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":"Online Controller Setpoint Optimization for Traction Control Systems Applied to Construction Machinery","authors":"A. Alexander, A. Sciancalepore, A. Vacca","doi":"10.1115/FPMC2018-8938","DOIUrl":"https://doi.org/10.1115/FPMC2018-8938","url":null,"abstract":"The development of a suitable traction control system for off-road heavy machinery is complicated by several different factors, which differentiate these machines from typical on-road systems. One such difficulty arises from the fact that they are often operated on ground conditions which can vary widely and rapidly. Due to this, traction control systems designed for these vehicles must be robust to a large array of surface types, and they must be capable of reacting quickly to significant changes in those types. In order to accomplish this, this paper proposes an online parameter optimization technique suitable for tuning the setpoint of a control system to maximize the tractive potential of a construction vehicle in real time. The traction control principle itself is based on selectively braking wheels which are slipping. It also attempts to account for the interactions of the transmission systems that deliver power from the engine to the wheels. This research uses a wheel loader as a reference machine for assessing controller performance. Drawing on previous work in simulation and controller design, a system model was developed which incorporates the vehicle dynamics of the machine as well as the behavior of the electrohydraulic brakes. This system model was leveraged to understand the effect of different optimization schemes on the performance of the traction control.\u0000 The self-tuning algorithm is based on a compound optimization method utilizing both a system identification component and a parameter tuning component. The first part optimizes the model parameters to fit it as well as possible to measured slip-friction data. Based on the results of this, the second part draws from theories of wheel traction to maximize a balance of pushing force and traction effectiveness. The result is a method which can achieve the proper setpoint based on real-time data describing the ground condition. This system was run first in simulation and then on a modified vehicle system. In both cases, the algorithm allows the controller to find better setpoints to improve the traction control performance online.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129511908","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 Survey of Industrial Internet of Things in the Field of Fluid Power: Basic Concept and Requirements for Plug-and-Produce","authors":"Raphael Alt, Justus Malzahn, H. Murrenhoff, K. Schmitz","doi":"10.1115/FPMC2018-8833","DOIUrl":"https://doi.org/10.1115/FPMC2018-8833","url":null,"abstract":"Driving aspects in the developments of the Industrial Internet of Things (IIoT) are based on markets demanding a highly flexible production on the one hand and, on the other hand, by the production industry looking for new business models. This is enabled by interconnecting intelligent devices and aggregating and analyzing huge amounts of data. In the section of field devices, targeted new developments are dealing with intelligent systems which support users in each stage of the product life cycle. During installation and commissioning of a new machine, the concept of Plug-and-Produce has been created in the production industry. It is relating to the analogy of Plug-and-Play in the field of information technology which makes it possible to recognize and use devices without additional effort across several platforms. Industrial production systems differ in some aspects from Plug-and-Play computer devices that these methods are not applicable without adjustments and more advanced considerations.\u0000 Solutions to support the commissioning process are scope of this contribution and analyzed theoretically by the example of the integration of an electro-hydraulic actuator.\u0000 Two results are highlighted in this contribution. Different IIoT related concepts and technologies (i.e. OPC-UA, Cyber-physical systems, semantics) are presented and merged to realize Plug-and-Produce as an holistic business process. Furthermore, the draft combines the domain of fluid power with the abstract and generalized concepts and models and gives an understanding of future requirements for fluid power field devices in the context of IIoT.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114473773","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":"Addressing Closed-Chain Dynamics for High-Precision Control of Hydraulic Cylinder Actuated Manipulators","authors":"Janne E. M. Koivumäki, Wen-Hong Zhu, J. Mattila","doi":"10.1115/FPMC2018-8839","DOIUrl":"https://doi.org/10.1115/FPMC2018-8839","url":null,"abstract":"Nonlinear model-based (NMB) control methods have been shown (both in theory and in practice) to provide the most advanced control performance for highly nonlinear hydraulic manipulators. In these methods, the inverse dynamics of a system are used to proactively generate the system actuation forces from the desired motion dynamics. To model the inverse dynamics in articulated systems, the Lagrange dynamics and the Newton-Euler dynamics are the most common methods.\u0000 In hydraulic cylinder actuated manipulators, a linear motion of the cylinder can be converted to a rotational joint motion between two links, creating closed-chain structures in the system. In Lagrange-dynamics-based control methods, the closed-chain structures are typically treated as an open-chain structure, which may raise the question of inaccurate system modeling. Contrary, the virtual decomposition control (VDC) approach is the first rigorous NMB control method to take full advantage of Newton-Euler dynamics, allowing to address the system nonlinear dynamics without imposing additional approximations.\u0000 In VDC, the actuated closed-chain structures can be virtually decomposed to open chain structures. To address the dynamics between the decomposed open chains, three specific terms (namely two load distribution factors and an internal force vector) need to be addressed. However, analytical solutions for these terms cannot be found in the literature. This paper provides the detailed solutions for these terms, which are further needed in a high-precision control of hydraulic robotic manipulators.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"274 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124089176","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":"Fuel Efficiency Optimization of a Baseline Wheel Loader and its Hydraulic Hybrid Variants Using Dynamic Programming","authors":"Mikko Heikkilä, M. Huova, J. Tammisto, M. Linjama, J. Tervonen","doi":"10.1115/FPMC2018-8853","DOIUrl":"https://doi.org/10.1115/FPMC2018-8853","url":null,"abstract":"In this paper, fuel consumption of a 5.7-ton municipal tractor in a wheel loader application is studied, and methods for improving the fuel efficiency are compared with each other. Experimental data from the baseline machine with load-sensing hydraulics has been gathered during a y-pattern cycle, and the data is inputted to an optimization function having realistic loss models for a hydraulic pump and diesel engine. Dynamic programming is used to analyze different system configurations in order to determine optimal control sequence for each system. Besides optimization of variable engine rotational speed on the baseline system during the working cycle (considering the point of operation), three hybrid supply systems are studied: 1) a hydraulic flywheel, 2) parallel supply pumps and 3) a throttled accumulator. These systems utilize a hydraulic accumulator as an energy source/sink alongside the diesel engine. The optimal sequence for charging and discharging of the accumulator is examined in order to minimize the fuel consumption of the machine. The idea is to use the lowest acceptable, constant engine rotational speed, to cut down the diesel losses. In addition, the study covers an analysis of adjusting the engine rotational speed for each point of operation also when the hybrid systems are considered. The results show that finding advantageous engine rotational speed for each loading condition can decrease the fuel consumption of the baseline machine around 14%, whereas hybridization of the supply system can further improve the result by a couple of percentage units. Hybrid systems also reduce engine’s maximum load by making it more uniform, which allegedly reduces emissions. The possibility of engine downsizing to further improve the fuel efficiency of hybrid systems is not considered, because the maximum engine power is usually determined by the hydrostatic transmission of a municipal tractor. However, the study assumes that actuators are controlled using traditional 4/3 proportional control valves; hence, there are still potential for greater fuel savings. For example, applying independent metering valves on the actuator control can further decrease the system losses.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"6 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124909059","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":"An Improved Transmission Line Model for Dynamic Laminar Flow Through Tapered Tubes","authors":"T. Wiens, Jeremy W. ven der Buhs","doi":"10.1115/FPMC2018-8881","DOIUrl":"https://doi.org/10.1115/FPMC2018-8881","url":null,"abstract":"This paper presents an improved method for time-domain modelling of transient laminar flow through tapered tubes. This method is based on the transmission line method (TLM), a technique using transfer functions and delays to calculate the pressures and/or flows at the ends of the tube. However, unlike previous methods that are limited to non-tapered tubes or are inaccurate at low frequencies, the method presented here is applicable across a wide range of taper ratios, dissipation numbers, and frequency content. The new model is compared in the frequency domain to a boundary value problem solution and in the time domain to a method of characteristics solution.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131529700","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":"Synthetic Esters and Dynamics of Pressure Compensated Proportional Directional Control Valves","authors":"J. Jakobsen, M. Hansen","doi":"10.1115/FPMC2018-8933","DOIUrl":"https://doi.org/10.1115/FPMC2018-8933","url":null,"abstract":"The purpose of this paper is to help reduce the uncertainty in behavior introduced when changing hydraulic oil from mineral oil (HLP) to biodegradable oil (synthetic esters - HEES) by comparing the behavior of proportional valves with HLP and with HEES at various temperatures.\u0000 The focus of this article is on classic proportional valves used in the industry. The study is based on tests and modelling with characterization of dynamic behavior in mind. The characterization is based on tests of two pressure compensated proportional valves, one with closed loop control of the spool position, and one without. The two ester types tested are one based on a saturated, fully synthetic ester and a regular fully synthetic ester.\u0000 The tests consist of steps and frequency responses. Both valves are tested at oil temperatures 20°C, 40°C and 60°C.\u0000 The adopted models are based on a third order linear model with parameters identified using frequency responses from actual valve tests.\u0000 The variation of amplitude and bias has some influence on the resulting frequency response especially at lower temperatures. But the general tendencies are unaffected by amplitude and bias.\u0000 As expected a clear tendency for both valves of increasing dampening at decreasing temperatures is seen regardless of oil type, but the increase in dampening is similar for all oil types.\u0000 The saturated ester leads to less bandwidth at lower temperatures for both valves, but the overall variations between all oil types stay within 1.66Hz of each other when tested with the same test parameters.\u0000 The investigation indicates that the difference in dynamic characteristics at 20°C caused by the different oil types can not be explained with variations in any single one of the classic liquid properties density and viscosity and more investigations are needed to identify the cause.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129002200","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}