Motion synchronization of HA/EHA system for a large civil aircraft by using adaptive control

Measurement and Control

Luo

Wang

et al. 2019

Self Cite

Most of the researchers are focusing to bring automation in mechanical systems. So, current research work presents a mechatronic system called active hydrostatic journal bearing that is a higher demand of fast-growing industrial needs. The objective is to improve the dynamics and static characteristics of hydrostatic journal bearing. To achieve the objective, a feedback servo controlled system is presented. A mathematical model is proposed for newly proposed active hydrostatic journal bearing with servo control. A comparison has been performed between the active hydrostatic journal bearing and traditional/conventional hydrostatic journal bearing under the influence of different dynamic conditions of load, viscosity, speed, and pressure. The results demonstrate that proposed active hydrostatic journal bearing has better performance, including controllability, stability, faster response, higher stiffness as well as better disturbance rejection. To further enhance the performance of proposed active hydrostatic journal bearing, two different control strategies are proposed such as proportional–integral–derivative and intelligent control. The results show that fuzzy logic–based intelligent control has faster response, greater amplitude reduction, and good stiffness against load. So, it shows that role of active lubrication in hydrostatic journal bearing will have potential applications in high load and high speed.

Section: Modeling For Active Hydrostatic Journal Bearing Systemmentioning

confidence: 99%

Section: Modeling For Active Hydrostatic Journal Bearing Systemmentioning

confidence: 99%

Fuzzy logic–based intelligent control for hydrostatic journal bearing

Measurement and Control

Luo

Wang

et al. 2019

Self Cite

“…According to previous studies (Rehman et al , 2016c; Rehman et al , 2016b; Rehman et al , 2016a; Waheed et al , 2015; Rehman et al , 2017), servo valve can be interpreted in a proportional mathematical function as follows: …”

Section: Mathematical Modeling With Servo-controlled Hydrostatic Bearing Systemmentioning

confidence: 99%

Linear extended state observer-based control of active lubrication for active hydrostatic journal bearing by monitoring bearing clearance

Guiyun

Xin

et al. 2019

ILT

Purpose This paper’s aim is modeling and simulation of an advanced controller design for a novel mechatronics system that consists of a hydrostatic journal bearing with servo control. The proposed mechatronic system has more worth in tribology applications as compared to the traditional hydrostatic bearing which has limited efficiency and poor performance because of lower stiffness and load-carrying capacity. The proposed mechatronic system takes advantage of active lubrication to improve stiffness, rotor’s stability and load-carrying capacity. Design/methodology/approach The current work proposes extended state observer-based controller to control the active lubrication for hydrostatic journal bearing. The advantage of using observer is to estimate unknown state variables and lumped effects because of unmodeled dynamics, model uncertainties, and unknown external disturbances. The effectiveness of the proposed mechatronic system is checked against the traditional hydrostatic bearing. Findings Proposed mechatronics active hydrostatic journal bearing system is checked against traditional hydrostatic journal bearing. It is found that novel active hydrostatic journal bearing with servo control has good tribology performance factors such as stiffness, less rotor vibration, no wear and friction under starting conditions and high load-carrying capacity under different conditions of spindle speed, temperature, initial oil pressure and external disturbance. The result shows that proposed mechatronics system has more worth in rotary tribology applications. Originality/value The current manuscript designs a novel active hydrostatic journal bearing system with servo control. The mathematical model has advantages in term of estimating unknown state variables and lumped effects because of unmodeled dynamics, model uncertainties and unknown external disturbances. The result shows improvement in dynamic characteristics of a hydrostatic journal bearing under different dynamic conditions.

“…Then, the continuity equation of flow for hydrostatic bearing can be used to get overall flow equation for hydrostatic bearing. 32,33 Where the flow delivered by servo valve to hydrostatic bearing is equal to the summation of squeezing flow, compressibility flow and pressure-velocity flow of hydrostatic bearing.…”

Section: Mathematical Modeling Of Servocontrolled Hydrostatic Bearing Systemmentioning

confidence: 99%

Control of active lubrication for hydrostatic journal bearing by monitoring bearing clearance

Advances in Mechanical Engineering

Guiyun

Luo

et al. 2018

Self Cite

Active hydrostatic journal bearings represent a mechatronic answer to the fast-growing industrial needs to highperformance rotary machineries. The aim of this research is to study and improve the dynamic characteristics of hydrostatic bearing, with four pockets or recess. In order to improve dynamic characteristics for hydrostatic journal bearing, this research presents an active hydrostatic journal bearing with servo control. The results of active hydrostatic journal bearing with servo control were compared with those of traditional hydrostatic journal bearing with capillary throttling. The dynamic characteristics of the newly proposed bearing and traditional bearing are studied and compared under different dynamic conditions such as variable speed, viscosity, load, pressure, and bearing clearance. The numerical result shows that the proposed active hydrostatic journal due to active lubrication has good performance including stability and controllability, high stiffness, faster response, and strong resistance. Furthermore, two strategies such as proportional-integral-derivative and integrator backstepping control are also presented to improve the performance and efficiency of active hydrostatic journal bearing with servo control. The result shows that integrator backstepping control is more effective than proportional-integral-derivative control in terms of faster response and greater amplitude reduction, quickly regaining equilibrium position, and good stiffness against load. Hence, it is observed that active lubrication in hydrostatic journal bearing provides us better dynamic characteristics which will have potential applications in heavy and high-speed machinery.