Cambridge University Engineering Department Research Articles

Scanning electron microscopy 1928-1965

The beginning of the general use of the scanning electron microscope (SEM) can be accurately dated to 1965 when the Cambridge Instrument Company in the U.K. marketed their Stereoscan 1 SEM (to be followed about 6 months later by JEOL in Japan). But development had been in progress intermittently over the previous 30 years in Germany, the U.S.A., France, and the U.K. where in 1948 work was begun in Charles Oatley’s department at the Cambridge University Engineering Department which led directly to the Stereoscan. The purpose of this paper is to trace the development of the SEM and to show that some of the ideas pul forward by the early workers were well ahead of their time and only became technologically practicable much later.The First proposal for the application of scanning to microscopy was made in 1928 by Synge, an Irish scientific dilettante, who conceived the near-field scanning optical microscope but did not attempt to build one.

Liquid metal embrittlement in failure analysis

Liquid metal embrittlement is an unusual but industrially quite important failure mechanism. Although it has been recognized for about a century, the phenomenon is still poorly understood at an academic level, and industrial awareness of potential problems is limited. A review of the published reports of failures involving liquid metal embrittlement is presented, indicating that the problem occurs in a wide variety of circumstances and often in quite surprising situations. An overview of the research being carried out at the Cambridge University Engineering Department is also presented. This work is aimed at investigating the initiation and propagation behavior of liquid metal embrittlement cracks in cylindrical tensile specimens.

Towards real CAD

Present-day computer-aided design (CAD) packages play only a small part in the area of mechanical engineering design, which involves the synthesis and embodiment of physical components to perform a pre-determined function without unwanted side effects. The computer cannot properly help the designer in this task until it is able to capture and process the function requirements of the design. This paper describes the computer system being developed for this purpose at the Engineering Design Centre at Cambridge University Engineering Department. The paper also explores some of the geometrical and programming implications raised.

Investigations on Research Engines with Visible and Infrared Optical Access

This paper details the progress made in an experimental study of knock in spark ignition engines undertaken between the Cambridge University Engineering Department and Ford Research and Engineering Centre. A general-purpose, optically accessed cylinder head of standard configuration and capable of high-speed operation has been designed and built. This head has been used in preliminary direct emission studies of knock. The same cylinder head, together with a photographic Ricardo Hydra, has been used in an infrared study of cylinder radiative emissions. By maximizing the combustion chamber surface emissions, observations regarding surface temperature characteristics with and without knock have been made. By minimizing the emissions from combustion chamber surfaces, the strong emission from the flame from itself has been used to produce once-per-cycle images of flame propagation.

A methodology for developing computer-based teaching programs

As the use of computers in higher education increases so the institutions concerned are recognising the need to use methods which will produce teaching programs on schedule and to pre-defined standards. At the Cambridge University Engineering Department a set of processes have been adapted to form a complete development methodology which is particularly relevant to teaching programs. Six months of practical experience in the use of the methodology has now been accumulated and this has been favourable. Further work will be carried out to evaluate the effectiveness of the teaching programs developed.

The Development of an Integrated Communications Demand Model for the British Telecommunications Business

This paper describes aspects of a project in which a computer model (I.C.D.M.) of the longer-term trends in demand for telecommunications media in the U.K. was developed and implemented. The work was undertaken by Cambridge University Engineering Department for the Long Range and Strategic Studies Division of British Telecom. The paper concentrates on the processes of developing and implementing the model as an aid in the formulation of robust investment and marketing strategies for British Telecom in the face of a rapidly changing technological environment and emergent competition. The value of the integrative and dynamic characteristics of the I.C.D.M. in this context is emphasized, and the role of a user-friendly colour graphics interface in encouraging managerial acceptance of the new tool is noted.

Recollections of the early days of SEM in the Cambridge University Engineering Department, 1948–53

SUMMARYAfter a brief survey of the early development of the scanning electron microscope in Germany and the U.S.A., the paper describes the work on the subject that was carried out in the Cambridge University Engineering Department, particularly in the years 1948–53. This and later work led directly to the Stereoscan SEM marketed by the Cambridge Instrument Company in 1965. The paper is illustrated with a number of micrographs produced by early scanning electron microscopes.

Astigmatism correction and determination of resolving power in the SEM

SUMMARYSome of the early work carried out on the first scanning instrument constructed in the Cambridge University Engineering Department is recalled. The methods then used for astigmatism correction and the determination of resolving power are described and contrasted with later developments, particularly those relating to the use of on‐line digital computer techniques.

The Acoustic Analogy—Thirty Years On

Journal Article The Acoustic Analogy—Thirty Years On Get access J. E. FFOWCS WILLIAMS J. E. FFOWCS WILLIAMS Cambridge University Engineering Department Search for other works by this author on: Oxford Academic Google Scholar IMA Journal of Applied Mathematics, Volume 32, Issue 1-3, January 1984, Pages 113–124, https://doi.org/10.1093/imamat/32.1-3.113 Published: 01 January 1984 Article history Received: 07 September 1983 Published: 01 January 1984

Microprocessor Control of a Robot Arm

A four-hour second-year experiment at Cambridge University Engineering Department is described in which a small robot arm is controlled by a microprocessor. The experiment is part of a full microprocessor laboratory programme. The aims for students are both to gain understanding of interfacing and stepping motor control, and to do simple arm performance calculations.

Letters to the editor

International Journal for Numerical and Analytical Methods in GeomechanicsVolume 7, Issue 1 p. 135-139 Letter to the Editor Letters to the editor D. V. Griffiths, D. V. Griffiths University of Manchester, Simon Engineering Laboratories, Manchester, EnglandSearch for more papers by this authorS. W. Sloan, S. W. Sloan Cambridge University Engineering Department Presently at Department of Engineering Science, Oxford University.Search for more papers by this authorM. F. Randolph, M. F. Randolph Cambridge University Engineering DepartmentSearch for more papers by this author D. V. Griffiths, D. V. Griffiths University of Manchester, Simon Engineering Laboratories, Manchester, EnglandSearch for more papers by this authorS. W. Sloan, S. W. Sloan Cambridge University Engineering Department Presently at Department of Engineering Science, Oxford University.Search for more papers by this authorM. F. Randolph, M. F. Randolph Cambridge University Engineering DepartmentSearch for more papers by this author First published: January/March 1983 https://doi.org/10.1002/nag.1610070113Citations: 1 Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume7, Issue1January/March 1983Pages 135-139 RelatedInformation

The early history of the scanning electron microscope

The article begins with an account of prewar German work, particularly that of von Ardenne, who established the theoretical basis of a scanning electron microscope and constructed an instrument which was primarily intended to overcome chromatic aberration when relatively thick specimens were examined by transmission. Neither this microscope nor a different one built a few years later in the U. S. A. attained sufficient resolution to gain acceptance and the reasons for this are examined. The remainder of the article deals with work carried out in the Cambridge University Engineering Department over the years from 1948 to about 1965, when the first successful commercial instrument was produced. The contributions made by successive research students are explained, as are also the nonscientific factors which influenced the course of the development.

Electroproduction education at Cambridge University Engineering Department

The term ‘electroproduction’ encompasses the whole range of processes and techniques related to the manufacture or processing of goods where the use of electricity is an essential feature. In the past it has not been generally recognised as a subject, in its own right, that should form part of the many educational curricula covering the varied aspects of engineering

Book review

Offshore Soil Mechanics edited by Philip George and David Wood. Cambridge University Engineering Department and Lloyd's Register of Shipping, London, 1976. 468 pp. £7.50 + shipping. Beach Processes and Sedimentation by Paul D. Komar. Prentice‐Hall, Inc. Englewood Cliffs, New Jersey, 1976. 429 pp., $26.95.

Influence of geometry and mode shape on the internal damping of vibration modes

Internal damping of vibration modes of plates and shells can depend on mode shape, boundary conditions, and geometry. A systematic theoretical investigation based on linear viscoelastic theory and Rayleigh's variational principle shows that in an isotropic material these effects stem from a complex Poisson's ratio analogous to the familiar complex Young's modulus, while for anisotropic materials they are influenced by other constants similarly becoming complex. The imaginary parts of these constants can not all be measured by the usual method of analyzing bar modes: measurements must be made on plates. A method is described and is illustrated by numerical and preliminary experimental results. Some effects of the kind described have been shown to be of great importance in the construction of musical instruments of the violin family, and they deserve attention in any situation where Q's of vibration modes are required to be accurately known. [We thank the Science Research Council for financial support and the Cambridge University Engineering Department for experimental facilities.]

Toward understanding violin plate tuning

As Hutchins has shown, violin makers observe a surprising sensitivity, to small plate-thickness perturbations, of the internal damping of vibration modes of violin plates. Progress towards a systematic theory of this phenomenon is reported. The method used provides a simple framework for describing the effect on internal damping of mode shape, boundary conditions, and geometry for a wide class of materials. One important fact to emerge is that more material parameters may enter than have traditionally been measured, and indeed the usual measurement technique employing thin strips is seen to be incapable of measuring them. A more suitable technique using flat plates is described and illustrated with some computations and preliminary experimental results. These confirm the prediction that “plate-tuning effects” similar to those found in wooden violin plates can also occur in isotropic plates, for frequencies well below the level where shear motion needs to be taken into account. [We thank the Science Research Council for financial support and the Cambridge University Engineering Department for providing experimental facilities.]

A cubic spline package. Part 2-The mathematics

Part 1 of this paper provided a user's guide to cubic spline package developed by the c.a.d. research group at Cambridge University Engineering Department. This part details the mathematical basis for the spline calculation used in the principal subroutine.

A cubic spline package. Part 1 — The user's guide

The computer-aided-design research group at Cambridge University Engineering Department wrote this spline package for use on the Atlas 2 computer at the CAD Centre, Cambridge. It has recently been implemented (by Dr Morris and Mr P. M. McLellan) for on-line users of ITT, and the examples in the text have been run on ITTS-RTS ∗ ∗ ITT-RTS is the reactive terminal service of ITT Ltd. . A version also exists for IBM 1130 and 360/370 computers. The heart of this set of programs is a spline subroutine of original construction which can handle any number of points without rounding-error difficulties, and which allows the user to permute the end conditions from a wide choice. The mathematical basis for this subroutine will be described in Part 2 of this paper.

Curvature profiles for plane curves

The computer-aided design research group at Cambridge University Engineering Department are investigating a new technique for integrating curvature profiles for plane curves, and this paper sets out the basic mathematical ideas behind their computer programs. The extension to three-dimensional curves and surfaces is also being investigated, but is not discussed in this paper.

Some experiments on the flow past a sphere

There is little published work on the flow past a sphere. Some experiments were carried out in the 1930s (see Fage), and other measurements have been made more recently (Cometta and Kendall). Much of the work has been restricted to flow visualisation and to measurements of drag and surface pressure distribution. Very few measurements have been made in the near wake.In the present paper, measurements of vortex shedding frequency, wake dimensions and static pressure up to three diameters downstream are reported. The experiments were carried out in the Aerodynamics Laboratory of the Cambridge University Engineering Department, under the supervision of Professor W. A. Mair.