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Fixture layout design is concerned with immobilization of the workpiece (engine mount bracket) during machining such that the workpiece elastic deformation is reduced. The fixture holds the workpiece through the positioning of fixturing elements that causes the workpiece elastic deformation, in turn, leads to the form and dimensional errors and increased machining cost. The fixture layout has the major impact on the machining accuracy and is the function of the fixturing position. The position of the fixturing elements, key aspects, needed to be optimized to reduce the workpiece elastic deformation. The purpose of this study is to evaluate the optimized fixture layout for the machining of the engine mount bracket.

In this research work, using the finite element method (FEM), a model is developed in the MATLAB for the fixture-workpiece system so that the workpiece elastic deformation is determined. The artificial neural network (ANN) is used to develop an empirical model. The results of deformation obtained for different fixture layouts from FEM are used to train the ANN and finally the empirical model is developed. The model capable of predicting the deformation is embedded to the evolutionary optimization techniques, capable of finding local and global optima, to optimize the fixture layouts and to find the robust one.

For efficient optimization of the fixture layout parameters to obtain the least possible deformation, ant colony algorithm (ACA) and artificial bee colony algorithm (ABCA) are used and the results of deformation obtained from both the optimization techniques are compared for the best results.

A MATLAB-based FEM technique is able to provide solutions when the repeated modeling and simulations required i.e. modeling of fixture layouts (500 layouts) for every variation in the parameters requires individual modeling and simulation for the output requirement in any FEM-based software’s (ANSYS, ABACUS). This difficulty is reduced in this research. So that the MATLAB-based FEM modeling, simulation and optimization is carried out to determine the solutions for the optimized fixture layout to reach least deformation.

Many a time the practicability of the machining/mechanical operations are difficult to perform costly and time-consuming when more number of experimentations are required. To sort out the difficulties the computer-based automated solution techniques are highly required. Such kind of research over this study is presented for the readers.

A MATLAB-based FEM modeling and simulation technique is used to obtain the fixture layout optimization. ANN-based empirical model is developed for the fixture layout deformation that creates a hypothesis for the fixture layout system. ACA and ABCA are used for optimizing the fixture layout parameters and are compared for the best algorithm suited for the fixture layout system.

THE Beagle B.206‐S aircraft is a low‐wing monoplane of all‐metal stressed skin construction powered by two Continental Type GTSIO‐520C engines driving Hartzell constant‐speed, fully feathering propellers.

NORTH Sea Aerial & General Transport, Ltd., a subsidiary of the Blackburn Aeroplane & Motor Co., Ltd., which operates a Royal Air Force Reserve Flying School at Brough, E. Yorks, has recently built an engine test room adjoining the engine repair shop and has installed a very ingenious engine test bed. Mr. T. Bancroft, Chief Engineer of the Flying School, is responsible for the design of the bed. With the exception of the brake gear, cooling fan, starting motor, switch gear and instruments the whole of the installation has been constructed by the Company.

For use with a turbine providing coolant for the blading, a nozzle vane comprising a root portion, a neck portion joined thereto, and a blade portion extending from said neck portion; said blade portion being partially defined by a leading edge and a trailing edge; a distributing chamber formed within said blade portion; said trailing edge having a series of openings therein; a plurality of small passages radiating from said chamber and communicating with said trailing edge; said root and neck portions being formed with a passage through them communicating with said chamber thereby providing a continuous path for the transfer of coolant from said root portion through said neck portion and said plurality of passages to said series of openings in said trailing edge.

A combined longitudinal control and stabilization mechanism, for an airplane provided with a control stick, comprising split flaps, a single cam to operate the said flaps for purposes of longitudinal and stabilization control, said single cam being actuated by the control stick by means of the movement of a shaft, for purposes of elevational control, and means mounted on the control stick whereby the shaft may be rotated independently of the control stick for purposes of stabilization.

A DIAGRAMMATIC layout of the main fuel system can be seen in fig. 14. Fuel from the tank is fed through a low pressure filter to the main fuel pump. This pushes the fuel through to the governor and throttle valve (integral with the governor). From the throttle valve the fuel passes through a non‐return valve into the burner ring. This non‐return valve prevents fuel leakage when the engine is shut down.

A MAJOR problem associated with the production of light aircraft is the ability to feed individual customer requirements into the build stages with a minimum amount of retrospective work. Orders for a number of aircraft to the same specification enable the production line to flow smoothly with a corresponding reduction in costs, and in order to achieve this objective for B.206 aircraft the production programme specifies two standards of build which anticipate minimum customer requirements. Differing standards of radio and navigational aids are required to suit home and export markets and by addition to the basic fits a wide range can be provided.

Japan's robot manufacturers are beginning to cast their eyes towards Europe. A number of tie ups with European companies have recently been announced.

Reports on the 1999 Manufacturing Week exhibition and in particular on the Automation, Production and Maintenance Equipment (APME) section. It highlights a number of assembly equipment vendors who increasingly are supplying flexible systems to meet the demand of smaller batch manufacture. A number of application examples are described, including assembly and test of weigh scales, a kettle base and a current sensor for white goods. Another prime technology identified is vision, which is becoming much more transparent in part‐feeding systems. Some vendors promoted the application of vision to robot guidance and an application is given of loading machining centres with several automotive castings delivered randomly on a fixtureless conveyor belt. Finally, a number of new transport systems introduced at the show are identified.