The paper deals with the structure of the adaptive control electro-hydraulic servo-system (EHSS) with external load disturbances, practical verification of the identification, and control algorithms. The electro-hydraulic servo system composed of a servo-cylinder controlled with a servo-valve is discussed. It is a strongly nonlinear object with parameters changing over time. Adaptive adjuster parameters were determined by means of current identification resulting in the parametric model. Identification was conducted on the basis of measurement of the controlling size and regulated size objects. The identified model of the object was applied to carry out the on-line synthesis of the proportional-integral-derivative (PID) controller. The selected problems connected with obtaining the algorithm of adaptive control are presented. The computer program for implementing the algorithm with numerical simulation and identification of the control physical model object were calculated. The aim of the research was to examine the effectiveness of the adaptive control method in an electro-hydraulic servo system, both theoretically and experimentally.

Background: Indirect measurements of flow rate serve to determine air consumption, leakage values and characteristics of compressed air systems (CASs). Method: A new method of indirect flow rate measurement in a pneumatic pipeline system was developed. The method enables to measure the controlled leakage in a branch line and was used to construct automatic measuring systems auditing the compressed air systems piping. Results: First, the leak-testing instrument LT-I 200 was designed, constructed, and tested as portable measurement device for the estimation of air leakage flow rate in pneumatic pipeline system. Next, based on the authors' patent, the automatic measuring system for the measurement of the leakage flow rate in industrial compressed air piping was developed. Conclusion: The measurement device was used to estimate of the leakage flow rate and cost of the energy losses in the compressed air piping system.

The study deals with the energy-saving process of hot open die elongation forging of heavy steel forgings on an 80 MN industrial hydraulic forging press. Three innovative energy-saving power supply solutions useful for industrial hydraulic forging presses were analyzsed. The energy-saving power supply of hydraulic forging presses consists in reducing electricity consumption by the electric motor driving the pumps, reducing the noise emitted by pumps and reducing leaks in hydraulic piston cylinders. The predicted forging force as a function of heavy steel forging heights for various deformation temperatures and strain rates was determined. A simulation model of the 80 MN hydraulic forging press is presented, which is useful for determining the time-varying parameters during the forging process. An energy-saving control for the hydraulic forging press based on the forging process parameters’ prediction has been developed. Real-time model predictive control (MPC) was developed based on multiple inputs multiple outputs (MIMO), and global predictive control (GPC). The GPC has been implemented in the control system of an 80 MN industrial hydraulic forging press. The main advantage of this control system is the repeatability of the forging process and minimization of the size deviation of heavy large steel forgings

The paper presents selected issues of positionforce control of electro-hydraulic servo system using adaptive methods. This kind of measure extends the capabilities of control system which uses only position measurements. Indirect adaptive control has allowed for the monitoring and updating the dynamic phenomena occurring in the drive.

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