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The guided missile system is considered as SISO plant with parameter perturbations. The structure of the missile system is not suitable for the use of classical linear controllers. On the other hand, the missile system should be capable of good performances, such as zero steady state error, less settling time etc. Standard VSC control laws fail to control the steady state error due to the structure of the system matrices. For this reason we have proposed two new robust output integral sliding mode controllers and design procedures. An integrator is included in the sliding function, which results in the reduction and removal of the output error. The total control consists of two parts: equivalent control which compensates the nominal regime of the missile system; and VSC which compensates the parameter perturbations (changes in Mach number, altitude and mass of the vehicle, etc.) of the missile system. We have derived new constructive sliding and stability conditions for both cases by using Lyapunov’s direct method. Computer simulations indicate that this approach yields a satisfactory control performance.

In the preface it is stated that a need exists for a ‘comprehensive treatment of the subject that will present fundamentals in broad perspective but without emphasis on any one type of system’. The book is written as a single volume introduction to the subject so as to fill this need in part. The missiles dealt with in the book are what, in this country, would be more properly called guided missiles; the author states that the broader description ‘advanced’ was adopted to avoid implying any unintended restriction upon the applicability of basic principles. The book is competently written and a number of diverse technical aspects are handled in a workmanlike manner. There is a refreshing soundness and depth to the book which regrettably is not often found in books on guided missiles from across the Atlantic. To cover a subject embracing so many different techniques in a book of less than 600 pages is, of course, a difficult task. The treatment on the whole therefore has to be concise. This in itself is not a failing as the reader will generally be expert in at least one of the areas and will gain enough from the book to refresh his memory and enough to see what are the main features applicable to guided weapons. In areas where the reader is less well trained it will be necessary for him to supplement the text by reading elsewhere. To aid him in this the book is adequately provided with references (without overburdening the text). The treatment is a formal presentation of the basic theories, emphasising the common ideas underlying, for example, signal detection in the presence of noise and quality control. The reader would finish the book with a sound idea of the fundamentals but with only the vaguest idea of how to set about the design of a missile. What is required is a sequel to this book where the logical design, say, of three or four types of missiles is worked through with a generous number of examples.

This book is the third volume in a series intended to provide a basis for instruction of graduate non‐specialist students in the technology of guided missiles. It is divided into three main sections, ‘Operations Research’ by G. Merrill. Navy Technical Director of the Jupiter Ballistic Missile Project and general editor of the series; ‘Armament’ by H. Goldberg, formerly Chief, Ordnance Electronics Division, National Bureau of Standards, and ‘Launching’ by R. H. Helmholz, Assistant to Director of Tests, U.S. Naval Air Missile Test Center.

THE twenty‐fifth international air show which is to be held at Lc Bourget, from June 6 to June 16, promises to be the largest and most competitive of any of the Salons which have been organized by the French Union Syndicalc des Industries Aeronautiqucs ct Spatialcs, since the first in 1909. Approximately 400 companies from seventeen countries will present their latest aerospace products on the ground and in the air—the British industry being represented by 65 leading firms.

THE Twenty‐fifth S.B.A.C. Flying Display and Exhibition is to be held at Farnborough during the week Monday, September 5, to Sunday, September 11, promises to be one of the most interesting yet held as for the first time member companies of the Society have nominated for entry aircraft from member countries of the European A.I.C.M.A. (Association Internationale des Contructeurs de Materiel Aérospatial) that are powered by British engines. Seven European aircraft will be taking part, four of them sponsored by Bristol Siddeley Engines Ltd. and three by Rolls‐Royce Ltd. The dominant theme of the Show will be collaboration, and it is fitting that the foreign aircraft have been sponsored by the aero engine manufacturers as they have advanced farther along this road than the airframe companies. Between them, they have close associations with practically all the major engine manufacturers in the Western world. Apart from the models and displays which will be mounted by the major airframe and engine manufacturers reflecting their growing involvement with European projects, the stands of the Associate Members of the Society of British Aerospace Companies will have many examples of materials, techniques and equipment that these companies are producing in support of current programmes, some of which will be for the American military aircraft now on order for the Royal Air Force and the Royal Navy.

This paper is a condensed version of Part 2 of ‘The place of the library in a guided missile organization’ given at the Aslib Aeronautical Group eighth annual conference, College of Aeronautics, Cranfield, 3rd‐5th April 1959.

ON December 20th, 1910, Mr. E. W. Dunne, the inventor of the arrow‐headed, tail‐less, twin screw biplane, made an experimental flight which deserves greater recognition than it has perhaps received. In order to demonstrate the inherent stability of the design, he flew a circuit at Eastchurch “hands‐off” while writing his observations of its behaviour. To do this he provided the controls with a set of locking levers designed to give a small number of set positions to correspond with turns, climbing, etc. The test was completely successful and Mr. Dunne returned safely to terra‐firma albeit this was the first time that he had turned this particular machine at any height !

THERE are at present some 45,000 aircraft of various types in service in the air forces of the non‐communist world. Most of these aircraft will need to be replaced in the course of the next decade. A growing number of the world's air forces are also being equipped with guided missile systems. It is not easy to put a monetary value on the business which will arise from this. But taking into account the fact that defence expenditure is showing little sign of declining anywhere in the world, and that air defence is likely to absorb an increasing proportion of defence budgets, the demand in the non‐communist world for military aircraft and missiles with their spares during the next decade could well amount in value to some £50 billion.

A laser seeker is an important element in missile guidance and control systems, responsible for target detection and tracking. Its control is, however, a challenging problem due to complex dynamics and various acting disturbances. Hence, the purpose of this study is to propose a systematic design, tuning, analysis and performance verification of a nonlinear active disturbance rejection control (ADRC) algorithm for the specific case of the laser seeker system.

The proposed systematic approach of nonlinear ADRC application to the laser seeker system consists of the following steps. The complex laser seeker control problem is first expressed as a regulation problem. Then, a nonlinear extended state observer (ESO) with varying gains is used to improve the performance of a conventionally used linear ESO (LESO), which enables better control quality in both transient and steady-state periods. In the next step, a systematic observer tuning, based on a detailed analysis of the system disturbances, is proposed. The stability of the overall control system is then verified using a describing function method. Next, the implementation of the NESO-based ADRC solution is realized in a fixed-point format using MATLAB/Simulink and Xilinx System Generator. Finally, the considered laser seeker control system is implemented in discrete form and comprehensively tested through hardware-in-the-loop (HIL) co-simulation.

Through the conducted comparative study of LESO-based and NESO-based ADRC algorithms for the laser seeker system, the advantages of the proposed nonlinear scheme are shown. It is concluded that the NESO-based ADRC scheme for the laser seeker system (with appropriate parameters tuning methodology) provides better control performance in both transient and steady-state periods. The conducted multicriteria study validates the efficacy of the proposed systematic approach of applying nonlinear ADRC to laser seeker systems.

In practice, the obtained results imply that the laser seeker system, governed by the studied nonlinear version of the ADRC algorithm, could potentially detect and track targets faster and more accurately than the system based on the common linear ADRC algorithm. In addition, the article presents the step-by-step procedure for the design, field programmable gate array (FPGA) implementation and HIL-based co-simulation of the proposed nonlinear controller, which can be used by control practitioners as one of the last validation stages before experimental tests on a real guidance system.

The main contribution of this work is the systematic procedure of applying the ADRC scheme with NESO for the specific case of the laser seeker system. It includes its design, tuning, analysis and performance verification (with simulation and FPGA hardware). The novelty of the work is also the combination and practical realization of known theoretical elements (NESO structure, NESO parameter tuning, ADRC closed-loop stability analysis) in the specific case of the laser seeker system. The results of the conducted applied research increase the current state of the art related to robust control of laser seeker systems working in disturbed and uncertain conditions.

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.