# POSITION CONTROL OF AN ELECTRO-HYDRAULIC SERVOSYSTEM - A non-linear backstepping approach

### Claude Kaddissi, Jean-Pierre Kenné, Maarouf Saad

#### Abstract

This paper studies the control of an electro-hydraulic servosystem using a non-linear backstepping based approach. These systems are known to be highly non-linear due to many factors as leakage, friction and especially the fluid flow expression through the servo-valve. Another fact, often neglected or avoided, is that such systems have a non-differentiable mathematical model for bi-directional applications. All these facets are pointed out in the proposed model of this paper. Therefore, the control of this class of systems should be based on non-linear strategies. Many experiments showed the failure of classic control with electro-hydraulic systems, unless operating in the neighborhood of a desired value or reference signal. The backstepping is used here to overcome all the non-linear effects. The model discontinuity is solved in this paper, by approximating the non-differentiable function by a sigmoid, so that the backstepping could be used without restrictions. In fact, simulation results show the effectiveness of the proposed approach in terms of guaranteed stability and zero tracking error.

#### References

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#### Paper Citation

#### in Harvard Style

Kaddissi C., Kenné J. and Saad M. (2004). **POSITION CONTROL OF AN ELECTRO-HYDRAULIC SERVOSYSTEM - A non-linear backstepping approach** . In *Proceedings of the First International Conference on Informatics in Control, Automation and Robotics - Volume 2: ICINCO,* ISBN 972-8865-12-0, pages 270-276. DOI: 10.5220/0001134402700276

#### in Bibtex Style

@conference{icinco04,

author={Claude Kaddissi and Jean-Pierre Kenné and Maarouf Saad},

title={POSITION CONTROL OF AN ELECTRO-HYDRAULIC SERVOSYSTEM - A non-linear backstepping approach},

booktitle={Proceedings of the First International Conference on Informatics in Control, Automation and Robotics - Volume 2: ICINCO,},

year={2004},

pages={270-276},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0001134402700276},

isbn={972-8865-12-0},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the First International Conference on Informatics in Control, Automation and Robotics - Volume 2: ICINCO,

TI - POSITION CONTROL OF AN ELECTRO-HYDRAULIC SERVOSYSTEM - A non-linear backstepping approach

SN - 972-8865-12-0

AU - Kaddissi C.

AU - Kenné J.

AU - Saad M.

PY - 2004

SP - 270

EP - 276

DO - 10.5220/0001134402700276