...Longke Wang; Wayne J. Book; James D. Huggins This paper proposes a novel hydraulic circuit for a single rod cylinder controlled by a variable displacement pump. The circuit arrangement not only gives the system high energy efficiency but also improves upon the internal instability of traditional...

...Mohammed A. El Sayed; Saeid Habibi This article presents the development of a multiple inner-loop control strategy for improving the performance of hydrostatic actuation systems. In these actuators, the presence of nonlinearities associated with pump/motor static friction and backlash, pressure...

...M. Z. Norhirni; M. Hamdi; S. Nurmaya Musa; L. H. Saw; N. A. Mardi; N. Hilman In an axial piston pump design, the swash plate plays an important role in controlling the displacement of the pump, especially in a closed loop system. In this paper, the axial piston pump is incorporated into the design...

...Noah D. Manring; Viral S. Mehta The objectives of this paper are to identify the design parameters that have the greatest impact on the bandwidth frequency of a pressure controlled, axial-piston pump. This study is motivated by the fact that a physical limitation for these machines has been...

... is characterized by a relatively low complexity and a reasonably high accuracy. A modular approach is pursued with respect to the first principles models of the hydraulic components, i.e., a hydraulic pump, spool valves, proportional solenoid valves, channels, and hydraulic cylinders, which reduces complexity...

...James D. Van de Ven; Allan Katz Hydraulic applications requiring a variation in the speed or torque of actuators have historically used throttling valve control or a variable displacement pump or motor. An alternative method is switch-mode control that uses a high-speed valve to rapidly switch...

...Wenjun Meng; Jeffrey C. Suhling A combined controller (CT-PBC) by contact task control (CTC) with passivity based controller (PBC) is introduced to control test system of high capacity hydraulic pump (HCHP) to measure its properties. It is compared with a vector controller; a torque feedback based...

...Zhiru Shi; Gordon Parker; Jonathan Granstrom Variable displacement, swash-plate controlled, axial-piston pumps are widely used in applications that require high pressure and variable flow rates. The pump consists of a rotating barrel assembly that houses several pistons in a circular array. A swash...

...J. M. Bergada; J. Watton; S. Kumar This paper analyzes the pressure distribution, leakage, force, and torque between the barrel and the port plate of an axial piston pump. A detailed set of new equations is developed, which takes into account important parameters such as tilt, clearance...

...Alessandro Roccatello; Salvatore Mancò; Nicola Nervegna Analysis of a variable displacement axial piston pump, as in other complex fluid power and mechanical systems, requires appropriate insight into three multidisciplinary domains, i.e., hydraulics, mechanics and tribology. In recent years...

...Noah D. Manring; Viral S. Mehta; Frank J. Raab; Kevin J. Graf The objective of this study is to identify the best indexed position of two rotating groups within a tandem axial-piston pump for attenuating the torque ripple amplitude that is exerted on the shaft. By attenuating the torque ripple...

...Massimo Rundo; Nicola Nervegna The paper brings to evidence the effect that geometry of the stator ring of variable displacement radial pumps bears on performance characteristics of these units. The type of motion of the stator ring (linear or rotational), the location of the center of rotation...

...Noah D. Manring; Zhilin Dong In this paper, the control and containment forces acting on the swash plate of an axial-piston pump are examined. The most novel aspect of this research is that it includes the analysis of a secondary swash-plate angle that is occasionally used in aerospace pump...

...Timothy G. McGee, Graduate Student; Justin W. Raade, Graduate Student; H. Kazerooni, Professor The authors present a novel power supply for mobile robotic systems. A monopropellant (e.g., hydrogen peroxide) decomposes into high temperature gases, which drive a free piston hydraulic pump (FPHP...

... switches for more efficient power conversion and/or to incorporate a control structure. A variety of power converters including electronic converters, hydraulic pumps, and clutched transmissions/differentials employ switches. It is shown how reduced order models can be derived using bond graphs and a VSS...

...Noah D. Manring; Suresh B. Kasaragadda In this paper, the theoretical flow ripple of an external gear pump is studied for pumps of similar size using different numbers of teeth on the driving and driven gears. In this work, the flow ripple equation is derived based upon the flow of incompressible...

...X. Zhang; S. S. Nair; N. D. Manring A robust adaptive pressure control strategy is proposed for a novel indexing variable-displacement pump. In the proposed approach, parametric uncertainties and unmodeled dynamics are identified to the extent possible using a model free learning network and used...

...Osama Gad; M. Galal Rabie; Refaat M. El-Taher This paper deals with the static and dynamic behavior of a variable displacement bent axis axial piston pump with power control. A mathematical model is deduced to predict the performance of the pump and its controller. The pump static and dynamic...

...Noah D. Manring; Yihong Zhang In this research, the volumetric efficiency of the axial-piston pump is examined as it relates to the compressibility losses of the fluid. In particular, two valve-plate geometries are compared to show that alterations in the valve-plate design can cause differences...

...X. Zhang; J. Cho, Graduate Students; S. S. Nair, Professor; N. D. Manring, Program Manager, A new, open-loop, reduced order model is proposed for the swash plate dynamics of an axial piston pump. The difference from previous reduced order models is the modeling of a damping mechanism not reported...