Visualization of Hydraulic Cylinder Dynamics by a Structure Preserving Nondimensionalization

Abstract

This paper reveals a new simplicity of a nominal hydraulic cylinder model whose original representation suffers from too many physical parameters. The eight-dimensional (8-D) parameter space in the original representation is reduced to a 3-D parameter space in the proposed nondimensional representation while preserving the parametric structure. To clarify comprehensive relations between the nonlinear dynamics and many physical parameters, an advanced direct search approach is suggested. More precisely, we can repeat the fast computation of the nonlinear dynamics and the updates of only three parameters without verifying any new simulator. The efficient visualization of the numerical solutions presents the best possible result corresponding to the analytical solution.

Magnetorheological Fluid Based Devices Reported in 2013–2018: Mini-Review and Comment on Structural Configurations

“…Therefore, this type of MRF mount is effective in controlling small excitations with relatively high frequency components. Recently, a new design structure, to avoid the block-up behavior, was proposed (Sakai and Stramigioli Visuali, 2018). In this design, the cores have been modified to balance the pressure of both the upper and lower chamber.…”

Analytical, Experimental, and Numerical Investigation of Energy in Hydraulic Cylinder Dynamics of Agriculture Scale Excavators

“…Let us consider a hydraulic arm whose nonlinear nominal model of Figures 1 and 2 is a coupling of the hydraulic cylinder dynamics [18] and a pump pressure dynamics defined later. First, the hydraulic cylinder dynamics is described by…”

“…Equation (2) assumes the steady flow and the negligible servo dynamics of an open-center valve [25,26]. See [18] for more details of the nonlinear nominal model.…”

“…Regarding model-based control of hydraulic machinery, the paper analyzes energy behaviors in hydraulic cylinder dynamics from the port-Hamiltonian point of view, which provides many links to model-based control at laboratory scale at least [12,13]. Note that the analyzed energy in this paper is not the global energy (e.g., [14][15][16][17]) defined for the whole hydraulic machinery but just one of the local energies defined for each joint whose analysis is still open [18] and critical for better understanding of the whole hydraulic machinery eventually. To the best of our knowledge, however, on agricultural scales that should be larger than the laboratory scale, such local energy is mainly analyzed in terms of statics [1] and is not fully analyzed in terms of dynamics.…”

“…To the best of our knowledge, however, on agricultural scales that should be larger than the laboratory scale, such local energy is mainly analyzed in terms of statics [1] and is not fully analyzed in terms of dynamics. On the agricultural scale, numerical energy behavior and experimental energy behavior in hydraulic cylinder dynamics have not been analyzed yet from the port-Hamiltonian point of view [12,13,18,19]. In the paper, on the agricultural scale, we discuss the analytical, experimental, and numerical energy behaviors of a Hamiltonian in hydraulic cylinder dynamics.…”