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Internal leakage is one of the key factors that influence the super-low speed performance of continuous rotary electro-hydraulic servo motor. Therefore, this paper aims to study the change rule of internal leakage for improving the low speed performance of motor.

The mathematical models of internal leakage of continuous rotary electro-hydraulic servo motor were established, and according to the working principle of the motor, the 3D models of internal leakage location were established. Simulation analysis was implemented on the continuous rotary electro-hydraulic servo motor by the finite element analysis software ANSYS based on the fluid-structure interaction theory.

The results show the deformation of motor’s key parts and the changing rule of internal leakage. The effect of the leakage to the low speed performance of electro-hydraulic servo motor was analyzed, and at the same time, the motor’s leakage experiment was also conducted to verify the validity of simulation results.

This paper lays the foundation for improving the low speed performance of motor.

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.

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.

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.

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.

THE S‐3A VEHICLE is equipped with 2 completely independent hydraulic systems which have been designated as the combined flight control/utility system. These systems are both structurally and hydraulically isolated from each other and are designed and installed in accordance with spec. MIL‐H‐5440 type II (−65° to 275°F temperature range) class 3000 (cutout pressure at pump is 3,100psi).

AT the end of the war in 1945, aircraft systems could still be classified as ‘auxiliary’ and ‘ancillary’—those which were essential for flight and those which were installed for reasons of safety, crew or passenger comfort and operational efficiency. Thus auxiliary systems generally included only the fuel system and ignition system, and many aircraft, particularly military, were flown into repair depots with one or more of the ancillary systems inoperative.

The Westland Lynx helicopter is a particularly fine example of the use of advanced fan technology in modern aircraft applications. The firm of Airscrew Howden have come a long way from their original manufacture of the wooden ‘prop’ but they still continue to play a very essential part in all types of aircraft flying today; this takes the form of sophisticated fan designs to cover a wide variety of special air‐movement requirements that can arise in this sector.

In this report, accounts will be presented on the experience obtained from approximately 100 practical applications of industrial robots. The industrial robots used derive partly from the company's own production as well as from other domestic and foreign robot manufacturers.

THE past two years have seen a notable increase in the number of services on aircraft for which some form of power is required. First, retractable undercarriages, followed by wing flaps, gun turrets, and automatic pilots, have demanded a light and compact source of power, capable of being transmitted to remote points on the machine. As suitable power units have become available, so have other applications presented themselves, with the consequent freeing of the pilot and crew from irksome manual effort.

Accles & Pollock Ltd. of Oldbury, Worcestershire, a TI Steel Tube Division company, will be exhibiting a comprehensive range of precision steel tube and tubular products, including plain, annularly convoluted and thin wall tube, at Farnborough.

OF the 450 plus numerical control systems for machine tools currently being used in the United Kingdom, well over 100 systems are being operated by companies in or associated with the aircraft industry. In fact, the aircraft industry has probably done more than any other industry to pioneer, encourage and develop the use of numerically‐controlled machine tools. On the other hand, the application of numerical control within the aircraft industry itself is still in its infancy and it is therefore the purpose of this survey to outline the characteristics of the range of control systems now available. According to Report No. 119 entitled ‘Numerical Control: An Economic Survey’ by the Production Engineering Research Association of Great Britain, a survey revealed that many of the early applications of numerical control to machine tools were carried out without being economically justified. At that time, many of the advantages of numerical control were highlighted while some of the problems associated with their use were either not fully understood or ignored. However, the experience gained by a number of operators over a period of years has now put the use of this type of equipment into proper perspective. Since numerically‐controlled machine tools cost between li to 4 times as much as conventional machines it is necessary to justify this higher cost by direct or indirect savings. The direct savings, which can be measured and expressed in terms of time and money or both, may occur in (i) the pre‐production stage, by the simplification or elimination of jigs and tools, (ii) the production stage, by the elimination of marking‐out and reductions in setting, machining, handling and inspection times, and (iii) the assembly stage, by reductions in fitting or assembly times as a result of improved product quality. Indirect savings, which tend to be intangible, are: the reduction in lead times, the ease of design modification, the savings in scrap or rectification work, the reduction in jig and tool storage costs, and the reduction of operator fatigue. However, the picture has its greyer tones, and to brighten these a joint study convention was recently held by the British Electrical and Allied Manufacturers' Association and The Machine Tool Trades Association to foster such improvements as: the adoption of a common programming approach involving if possible a common numerical control language, the development of new machine tools specifically intended for use with numerical control systems and a greater degree of Government support for the introduction of numerically‐controlled machine tools used on Government production contracts. It is not the purpose of this article to describe the performance of machine tools equipped with numerical control systems but merely to present a survey of systems available. However, wherever possible examples have been quoted of the application of the numerical control system to particular machine tools—and a large number of these to machine tools being used in the aircraft industry. For a more detailed account of the application of numerically controlled machine tools, the reader is referred to the article beginning on p. 232, and to PERA Report No. 119. This PERA Report is a major contribution to literature on this subject and we are happy to acknowledge the use of a certain amount of the information contained in that Report in the following article.

NOT perhaps the most vintage of Farnboroughs from the point of view of new aircraft and new technology, but undoubtedly one of the most successful in relation to the business done. Some fifteen major orders worth over £32½ million were announced, bringing the total order book for the industry this year to more than £782 million already. This exceeds by a handsome margin the new business won by the industry in any nine‐month period in the past, and it is expected that by the end of the year orders worth well over £800 million will have been received. Highlights of the new British hardware on show were the Hawker Siddeley Nimrod and production Harriers on the military side; the B.A.C. One‐Eleven 500, the Handley Page Jetstream, the Garrett‐engined Short Skyvan, and the Beagle Pups showed the resurgence of the industry's civil interests. The number of foreign aircraft that appeared, sponsored in the main by Rolls‐Royce, bore witness to the strength of Britain's aero engine and aircraft equipment industry, and further evidence of this was found in the exhibition proper with many examples of major items of equipment having been adopted for overseas markets. The overall impression at Farnborough was a new‐found confidence in the future of the industry exemplified by a more aggressive and effective export sales policy that has already proved our ability to deliver the goods. It is not possible to cover all the exhibits shown at Farnborough, but the report following describes many of the interesting items.