On the Synthesis of Manipulator Drive Mechanism of Hydraulic Excavators

Krasimir Ganchev^1,

¹Central Laboratory of Mechatronics and Instrumentation, Bulgarian Academy of Sciences, Sofia, Bulgaria

Cite this paper:
Krasimir Ganchev. On the Synthesis of Manipulator Drive Mechanism of Hydraulic Excavators. American Journal of Mechanical Engineering. 2022; 10(1):28-33. doi: 10.12691/ajme-10-1-4

Abstract

In the kinematic chain of the manipulator of the hydraulic excavators, the drive of the revolute pairs is carried out by a hydraulic cylinder jointed to the both links of the pair, which realizes a planar drive mechanism of the type - Inverted Slider-Crank Mechanism, centric type (ISCM). The power capabilities of the ISCM are described by the basic transfer function of the mechanism dS/dφ, which fully describes the driving moment of the ISCM in dimensionless form. The synthesis of this mechanism begins with a preliminary choice of the small parameter λ=R/L<1, equal to the ratio of the lengths of the links of the ISCM revolute pair. The synthesis then proceeds in a few steps. First, the two moment functions are fitting - the moment of the external forces and the driving moment of the hydraulic cylinder, respectively in their dimensionless form. So that for the entire considered range of ISCM, the driving moment of the hydraulic cylinder must be greater than the external moment. In this stage, all the angles of the mechanism are fully determined, as well as the coefficient K, which converts the external moment into a dimensionless form. This is followed by next step in which the cylinder force F and the ISCM metric - the lengths R and L of the rotary pair links, are determined. However, here the coefficient K=F.R defines the two unknowns in a product, which means that by choosing a standard cylinder force F_o, the dimension R is calculated from the above relation. This can be repeated several times until acceptable mechanism dimensions and a suitable cylinder are obtained. Several examples of the described synthesis are given: an external moment with equal values at both ends of the considered range and an external moment from the forces of gravity. Of course, optimization procedures can be performed at various points in the synthesis procedure.

Keywords:
synthesys inverted slider-crank drive mechanism hydraulic excavators

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References:

[1]	Myszka D., Machines and mechanisms: applied kinematic analysis-4th ed. Pearson Education, Inc., publishing as Prentice Hall, 2012.
[2]	Bu F. and Yao B., “Nonlinear model based coordinated adaptive robust control of electro-hydraulic robotic arms via overparametrizing method”. February 2001, in - IEEE International Conference on Robotics and Automation 4: Proceedings, 3459-3464, vol. 4.
[3]	Valdiero A., Guenther R., De Pieri E. and Negri V. (2013). “Cascade Control of Hydraulically Driven Manipulators With Friction Compensation”. International Journal of Fluid Power, March 2007, 8(1):7-16.
[4]	Hao W., “Analysis report of 2010 excavator market in China,” Construction Machinery Technology & Management, vol. 2, article 23, 2011.
[5]	Ni T., Zhang H, Yu C., Zhao D. and Liu S., “Design of highly realistic virtual environment for excavator simulator”. Computers and Electrical Engineering, vol. 39, no. 7, pp. 2112-2123, 2013.
[6]	Xu J. and Yoon H-S., “A Review on Mechanical and Hydraulic System Modeling of Excavator Manipulator System”. Journal of Construction Engineering. Volume 2016, Article ID 9409370.
[7]	Gnasa U., Thielecke K., Modler K-H. and Richter E-R., “Design and development of a hydraulic manipulator with mechanism/Pro”. International ADAMS users’ Conference, Berlin, 17-18 Nov 1999.
[8]	Mitrev R., “Web Based Enviroment for Design and Analysis of Hydraulic Escavator”. Journal of Multidisciplinary Engineering Science and Technology (JMEST), Vol. 2, Issue 12, December 2015.
[9]	Patel D., Patel B. and Patel M., “A Critical Review on Kinematics of Hydraulic Excavator Backhoe Attachment”. Int. J. Mech. Eng. & Rob. Res. Vol. 4, No. 2, April 2015.
[10]	Ganchev K., “Inverted Slider-Crank Mechanism Driven by Hydraulic Cylinder: Transfer Functions and Approximations”, Engineering Mathematics. Volume 6, Issue 1, June 2022, pp. 1-5.
[11]	Ganchev K., “Synthesis of Slider-Crank Mechanism Driven by Hydraulic Cylinder”. Mechanika na Mashinite, 34/2001, pp. 75-95.
[12]	Koev P. and Vitliemov V., “Тwo-Criterion Optimization Kinematic Synthesis of Slider-Crank Mechanism”. Mechanika na Mashinite, vol.5 (20), 4/1997, pp.30-34.
[13]	Petrovic G., Pavlovic J., Madic M. and Marinkovic D., “Optimal Synthesis of Loader Drive Mechanisms: A Group Robust Decision-Making Rule Generation Approach”. Machines 2022, 10(5), 329.
[14]	Mitrev R. and Todorov T., “Multicriteria Optimal Selection of a Hydraulic Cylinder for Drive Mechanisms”. FME Transactions, 49/2021, 501-510.
[15]	Pavlovic J., Janosevic D. and Jovanovic V., “Optimization of manipulator drive mechanisms of hydraulic excavators on the basis of the tribological criterion”. Scientia Iranica, B (2020), 27(5), 2372-2381.
[16]	Zou Z., Chen J. and Pang X., “Optimum dimensional synthesis for the working mechanism of a hydraulic excavator to improve the digging performance”. SAGE journals, Oct.2017.