scholarly journals CALCULATION OF THREE-DIMENSIONAL HYDRAULIC ACTUATOR OF THE WORKING BODIES OF ATTACHMENTS AND TRAILERS IN THE MACHINE-TRACTOR UNIT

2020 ◽  
Vol 0 (2) ◽  
pp. 24-30
Author(s):  
Vladimir Mandryka ◽  
Vladimir Krasnokutskiy ◽  
Dmitry Vilnyi
Keyword(s):  
Three Dimensional ◽  
Hydraulic Actuator ◽  
Working Bodies

Advances in Actuation Systems to Improve Vehicle Performance and Safety

2003 ◽  
Author(s):  
John S. Brader ◽  
Nathan R. Trevett ◽  
David N. Rocheleau
Keyword(s):  
System Modeling ◽  
Three Dimensional ◽  
Active Suspension ◽  
Input Voltage ◽  
Hydraulic Actuator ◽  
Vehicle Performance ◽  
Camless Engines ◽  
Camless Engine ◽  
Suspension Model ◽  
Actuation Systems

Actuation and modeling for drive-by-wire applications are discussed. Previous work in advanced actuation for two automotive systems, active suspension and camless engines, is surveyed, outlining the major advancements throughout the previous decade. More recent research in these areas is discussed and focuses on recent improvements to system modeling and design. Specifically, a four-corner suspension model and a piezoelectric piloted hydraulic actuator for engine valve actuation are introduced. The four-corner suspension model addresses the three-dimensional parameters associated with active suspension design and improves upon the accepted quarter-car model. The piezoelectric based camless engine actuator is introduced as the next generation of camless engine actuation systems and addresses control issues through the relationship between input voltage and piezoelectric displacement.

scholarly journals Modelling workflow forest fire soil - thrower with energy-saving hydraulic drive

2018 ◽  
Vol 7 (4) ◽  
pp. 182-189
Author(s):  
Петр Попиков ◽  
P. Popikov ◽  
П. Гончаров ◽  
P. Goncharov ◽  
Андрей Шаров ◽  
...  
Keyword(s):  
Energy Saving ◽  
Forest Fire ◽  
Hydraulic System ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Hydraulic Drive ◽  
Spherical Shape ◽  
Algebraic Equations ◽  
Working Bodies ◽  
Three Dimensional Space

The article is a schematic diagram of the hydraulic soil-thrower with connection air-charged accumulator which stores energy during overload when working bodies meeting with obstacles, while avoiding the operation of safety valves and conversion hydraulic energy into heat. Mathematical model that comprehensively describes the events taking place: the rotation and movement of the rotor soil-thrower rotor interaction with the ground and obstacles, the drive ground in space. In the method of the soil and the obstacles presented a collection of a large number (about 2000 ... 10000) spherical elements of small size, enabled communicate both among themselves and with the blades soil-thrower. The simulation is performed in three-dimensional space XYZ, where in the same elements have a spherical shape with the same diameter. With in the framework of the model developed by the working surfaces are represented as a set of elementary triangles. Rotor soil-thrower model with some degree of desensitization is represented by four rectangular blades, each of which consists of two triangles. In the process of simulation reproduced rotation of the rotor and the calculation of the interaction with the elements of triangular surfaces ground and obstacles. To solve the system of differential-social and algebraic equations, which laid the basis for the model, time-operated computer program "Program for modeling the work of forest fire soil-thrower with energy saving action hydraulic drive" program time to work in Borland Delphi environment 7.0 language Object Programming PascalIzucheny soil-thrower stage of interaction with the irresistible preption. Using the powering hydraulic system improves the uniformity of rotation of the rotor, to reduce energy costs for rotorus rotation by 12%.

scholarly journals Design of the universal agricultural working body and study of its parameters

2018 ◽  
Vol 224 ◽  
pp. 05006 ◽  
Author(s):  
Sergey V. Belousov ◽  
Sergey A. Pomelyayko ◽  
Vladislav V. Novikov
Keyword(s):  
Computer Aided Design ◽  
Three Dimensional ◽  
Experiment Planning ◽  
Design Tools ◽  
Computer Aided ◽  
Scientific Approach ◽  
Factors Of Influence ◽  
Working Bodies ◽  
Aided Design ◽  
Work Done

The article is devoted to the scientific approach with the help of computer-aided design tools for modeling the processes of interaction of tillage tools with soil. The article has an applied character, which is expressed in the fact that the method of computer-aided design in Mathcad using software CAD COMPASS 3D has been used. The analyses of expressions in the form of three-dimensional graphs are widely presented and their detailed review is given, which can be used to perform the improvement of the design of units that perform the main treatment of the soil with a turnover of a layer. As a result of the work done, there was obtained a combined plowshare with additional flat-cutting working bodies, there was made a matrix of experiment planning, there was obtained a graph of the dependence of the width grip of the flat-cutting razor on the speed of the arable unit. There were substantiated the factors of influence on performance as a result of using the planning of the two-factor experiment due to the orthogonal plan, there were determined the optimal settings of the operation modes of the plowshare.

Operational Envelopes for Working Bodies of Mechanisms and Manipulators

1998 ◽  
Vol 120 (1) ◽  
pp. 84-91 ◽  
Author(s):  
E. J. Haug ◽  
F. A. Adkins ◽  
Chi-Mei Luh
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Underlying Mechanism ◽  
Three Dimensions ◽  
Vehicle Suspension ◽  
Kinematic Constraint ◽  
Working Bodies ◽  
Operational Envelope ◽  
Vehicle Suspension System ◽  
Three Dimensional Space

The set of all points in space that are occupied by points in the working body of a mechanism or manipulator, for some kinematically admissible configuration, is defined as its operational envelope. Criteria for points on the boundary of the operational envelope of working bodies with smooth boundaries are developed, for both parametric and equation representations of domains and boundaries of working bodies, in two-and three-dimensional space. The criteria derived involve kinematic constraint equations for the underlying mechanism and equations that characterize the shape of the working body. A row rank deficiency condition is derived as a criterion for the boundary of the operational envelope, and numerical methods based on this condition for mapping the boundary are presented. Examples involving a planar Stewart platform with a dome attached and the wheel assembly of a vehicle suspension system in three dimensions are analyzed numerically.

Operational Envelopes for Working Bodies of Mechanisms and Manipulators

1995 ◽  
Author(s):  
Edward J. Haug ◽  
Frederick A. Adkins ◽  
Chi-Mei Luh
Keyword(s):  
Numerical Methods ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Underlying Mechanism ◽  
Kinematic Constraint ◽  
Rank Deficiency ◽  
Constraint Equations ◽  
Working Bodies ◽  
Operational Envelope ◽  
Three Dimensional Space

Abstract The set of all points in space that can be occupied by any point in the working body of a mechanism or manipulator is defined as its operational envelope. Criteria for points in and on the boundary of the operational envelope of working bodies with smooth boundaries are developed, for both parametric and equation representations of domains and boundaries of working bodies in two- or three-dimensional space. The criteria derived involve kinematic constraint equations for the underlying mechanism and equations that characterize the shape of the working body. A row rank deficiency condition is derived as a criterion for the boundary of the operational envelope, and numerical methods based on this condition for mapping the boundary are presented. An example involving a planar Stewart platform with a dome attached is analyzed numerically.

Development of a Hydraulic Actuator to Superimpose Oscillation in Metal-Forming Presses

2011 ◽  
Vol 473 ◽  
pp. 217-222 ◽  
Author(s):  
Bernd Arno Behrens ◽  
Sven Hübner ◽  
Richard Krimm ◽  
Christian Wager ◽  
Milan Vucetic ◽  
...  
Keyword(s):  
Metal Forming ◽  
High Frequency ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Hydraulic Cylinder ◽  
High Frequency Oscillation ◽  
Hydraulic Actuator ◽  
Simulation Code ◽  
Actuation System ◽  
Piston Valve

A novel principle of a rotary piston valve and a high-frequency cylinder for a hydraulic actuation system are presented. This system will be utilized in metal-forming presses to superimpose a high-frequency oscillation on the movement of the ram. This technique was proven to enhance the forming parts quality, to extend the process limits and to reduce the forming force significantly. The key components of the valve are a stator and a rotary piston with radial drilled holes that is designed to provide a pulsating pressure and mass flow rate at a high frequency. A hydraulic cylinder is connected to the valve and converts the pulsating flow into a dynamic process force. The valve and the cylinder will be mounted on the bolster plate of a metal-forming press. In order to superimpose oscillation in the main forming direction, the cylinder is centered under the punch of the metal-forming tool. Three-dimensional computational fluid dynamics (CFD) simulations have been conducted to evaluate and to optimize the designs of the main components of the system. Hereby the commercial simulation code of ANSYS CFX was employed to determine the properties of the cylinder and the valve. Through its mesh motion technique, this simulation code allows the flow analysis between the rotary and the stationary part of the valve. Furthermore the dynamic characteristics of the system have been investigated under the influence of inertia and the compressibility of oil.

The Flexural Behavior of Buried Steel and Composite Pipes Pulled Relative to Dense Sand: Experimental and Numerical Investigation

2012 ◽  
Author(s):  
Mohamed Almahakeri ◽  
Ian D. Moore ◽  
Amir Fam
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Element Model ◽  
Flexural Behavior ◽  
Fiber Reinforced Polymers ◽  
Burial Depth ◽  
Soil Resistance ◽  
Hydraulic Actuator ◽  
Dense Sand ◽  
Significant Difference

The flexural behavior of flexible buried pipelines subjected to lateral earth movements is investigated. Two types of pipeline materials, steel and then glass-fiber reinforced polymers (GFRP), are examined. Bending tests are conducted, where two parallel cables attached to a hydraulic actuator load the buried pipe. The study investigated three burial depth-to-diameter ratios (H/D = 3, 5, and 7) representing shallow to deep burial depths commonly used in energy pipeline construction. A three dimensional finite element model for this loading case has also been developed. Data from the numerical simulations are presented and compared to the experimental measurements. This paper provides an overview of the outcomes for this project. For example, while soil resistance was very similar for the two pipe types, the GFRP pipes demonstrated superior flexibility in longitudinal bending compared to the steel pipe. Furthermore, the finite element analyses were able to depict both this similarity in soil resistance, and the significant difference in flexural behavior of the two different pipe materials, the same phenomena observed during testing.

The orbit of Pluto over a long interval of time

1966 ◽  
Vol 25 ◽  
pp. 227-229 ◽  
Author(s):  
D. Brouwer
Keyword(s):  
Periodic Orbit ◽  
Numerical Integration ◽  
Restricted Problem ◽  
Three Dimensional ◽  
The Third ◽  
Circular Restricted Problem ◽  
Resonance Relation

The paper presents a summary of the results obtained by C. J. Cohen and E. C. Hubbard, who established by numerical integration that a resonance relation exists between the orbits of Neptune and Pluto. The problem may be explored further by approximating the motion of Pluto by that of a particle with negligible mass in the three-dimensional (circular) restricted problem. The mass of Pluto and the eccentricity of Neptune's orbit are ignored in this approximation. Significant features of the problem appear to be the presence of two critical arguments and the possibility that the orbit may be related to a periodic orbit of the third kind.

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