Fuzzy Controlled Hydraulic Excavator with Model Parameter Uncertainty

The hydraulic actuated excavator, being a non-linear mobile machine, encounters many uncertainties. There are uncertainties in the hydraulic system in addition to the uncertain nature of the load. The simulation results obtained in this study show that there is a need for intelligent control of such machines and in particular interval type-2 fuzzy controller is most suitable for minimizing the position error of a typical excavator-s bucket under load variations. We consider the model parameter uncertainties such as hydraulic fluid leakage and friction. These are uncertainties which also depend up on the temperature and alter bulk modulus and viscosity of the hydraulic fluid. Such uncertainties together with the load variations cause chattering of the bucket position. The interval type-2 fuzzy controller effectively eliminates the chattering and manages to control the end-effecter (bucket) position with positional error in the order of few millimeters.




References:
[1] J. Y. Alaydi, "Mathematical modeling for pump controlled system of
hydraulic drive unit of single bucket excavator digging mechanism,"
Jordan Journal of Mechanical and Industrial Engineering, vol. 2, no. 3,
pp. 157-162, Sep. 2008.
[2] B. Yao, F. Bu, and G. T. C. Chiu, "Nonlinear adaptive robust control of
electro-hydraulic servo system with discontinuous projections,"
Proceedings of the 37th IEEE Conference on Decision & Control, USA,
Dec. 1998, pp. 2265-2270.
[3] S. Tafazoli, C. W. De Dilva, and P. D. Lawrence, "Tracking control of
an electrohydraulic manipulator in the presence of friction," IEEE
Transaction on Control Systems Technology, vol. 6, no. 3, pp. 401-411,
May 1998.
[4] J. Shao, L. Chen, Y. Ji, and Z. Sun, "The Application of fuzzy control
strategy in electro-hydraulic servo system," Proceeding of International
Symposium on Communications and Information Technologies
(ISCIT2005), China, 2005, pp. 159-164.
[5] H. Q. Nguyen, "Robot low level control of robotic excavation," Ph. D.
thesis, University of Sydney, Australia, 2000.
[6] X. Zong-Yi, G. Qiang, J. Li-Min, and W. Ying-Yin, "Modelling and
identification of hydraulic system and its application," Proceedings of
the 17th World Congress: The International Federation of Automatic
Control, Seoul-Korea, July 2008, pp. 6446-6451.
[7] M. Muvengei and J. Kihiu, "Bond graph modelling of mechanical
dynamics of an excavator for hydraulic system analysis and design,"
International Journal of Mechanical, Industrial and Aerospace
Engineering, vol. 3, no. 4, pp. 248-256, 2009.
[8] Y. Liu, S. M. Hasan, and H-N. Yul, "Modelling and remote control of an
excavator," International Journal of Automation and Computing, vol. 7,
no. 3, pp. 349-358, Aug. 2010.
[9] G. Kothapalli and M. Y. Hassan, "Design of a neural network based
intelligent PI controller for a pneumatic system," IAENG International
Journal of Computer Science, vol. 35, no. 2, 2008.
[10] B. Li, Y. Jun, G. Gang, Z. Yonghua and, L. Wenxing, "High
performance control of hydraulic excavator based on fuzzy-PI softswitch
controller," IEEE International Conference on Computer Science
and Automation, China, June 2011, pp. 676-679.
[11] J. M. Mendel, Uncertain rule-based fuzzy logic systems: Introduction
and new directions, NJ: Prentice Hall PTR, 2001.
[12] M. B. Ozek, and Z. H. Akpolat, "A Software tool: Type-2 fuzzy logic
toolbox," Computer Application in Engineering Education, 2008, vol.
16, no. 2, pp. 137-146, 2008.
[13] E. Qugli, I. Lagrat, and I. Boumhidi, "A Type-2 fuzzy adaptive
controller of a class of nonlinear system," International Journal of
Computational Intelligence, vol. 4, no. 4, pp. 282-288, 2008.
[14] R. Martínez, O. Castillo, and L. T. Aguilar, "Intelligent control for a
perturbed autonomous wheeled mobile robot using Type-2 fuzzy logic
and genetic algorithm," Journal of Automation, Mobile Robotics
Intelligent Systems, vol. 2, no. 1, pp. 12-22, 2008.
[15] Y. S. Chen, and L. Yao, "Robust Typ-2 fuzzy control of an automatic
guided vehicle for wall-following," 2009 International Conference of
Soft Computing and Pattern Recognition, 2009,pp. 172-177.
[16] A. V. Akkaya, "Effect of bulk modulus on performance of a hydrostatic
transmission control system," Sadhana, vol. 31, pp. 543-556, 2006.
[17] E. G. Nezami, Y. Hashash, D. Zha, and J. Ghaboussi, "Simulation of
front end loader bucket-soil interaction using discrete element method,"
International Journal for Numerical and Analytical Methods in
Geomechanics, vol. 31, pp. 1147-1162, 2007.
[18] O. Costillo and P. Melin, Type-2 fuzzy logic theory and applications,
Berlin: Spring-Verlag, 2008.
[19] T. Viersm, Analysis, synthesis and design of hydraulic Servosystems
and Pipelines, Nederland: University of Delft, 2nd Edition, 1990.
[20] Y. Zao and E. G. Collins, "Fuzzy PI control of weight belt feeder," IEEE
Transaction on Fuzzy Systems, vol. 11, no. 3, pp. 311-319, June 2003.
[21] L. Reznik, Fuzzy Controllers, Newnes, Australia, 1997