Message from the President

Dear IFToMM colleagues:

And now, the end is near, and so I am here saying farewell as your President for the past four years, which have been quite exciting, indeed. We have gone through an extensive exercise of opinion-gathering in our attempt to define the IFToMM we envision for the 21st Century. The issues around this discussion touch, first and foremost, on the theory and practice of machines and mechanisms; besides, on governance, organization, and communication. The very name of the Federation could not escape this discussion.

Thanks to the input received from so many of you, we could reach the consensus that IFToMM is our trade mark and we shouldn't change it, but at the same time, we need not stick to the original name that the founding fathers coined one-and-a-half scores ago---IFToMM became a thirtysome this year. Thus, rather than associating a meaning to ``IFToMM'', we want to upgrade this accronym to the category of name, while attaching our mission statement to the name, not only for ease of identification, but also to remind ourselves that we have a mission. A proposal was put forth to the IFToMM community at large, last May, along these lines. The proposal was studied by the Constitution Committe, which suggested a streamlining of the mission statement, so that, according to the current proposal, we would be identified, should the constitutional changes be democratically approved, as


The Constitution Committee is working on a new draft of the Constitution that includes the package of constitutional reforms circulated last May, and already discussed during the Ninth General Assembly in Oulu. Please note that the proposed constitution and the current one have been available at the IFToMM Home Page, the former since last May, the latter for the last three years. The Constitution is thus available to the IFToMM community at large, and to anybody wanting to know about IFToMM.

The next century is around the corner. Contrary to popular belief, the first year of the century and the millenium is 2001, rather than 2000, but this is not a major issue---except for the Y2K Bug, which seems to be more or less under control. It is my strongest belief that IFToMM is ready to welcome the challenges ahead. A major challenge that we have faced in the last two decades has been a takeover by IT, the new accronym to denote computer technology, in people's attention. The outcome has been a reallocation of R & D budgets, with the lion's share going to our colleagues of the disciplines at the core of IT development. One more symptom of the same syndrome has been the shrinking of the number of students and staff in Mechanical Engineering departments, with a dramatic drop in mechanism and machine science (MMS) all over the world. Universities that were stallwarts of MMS have seen their core curriculum phasing out basic courses in the underlying disciplines. What this indicates is that the old TMM that we knew this century has no chance in the coming century. TMM has to be enriched with input from electronics, automation, and computer science, to mention but a few of sister disciplines. The integration of these disciplines with traditional TMM has led to what is known as Mechatronics, and which is one of the major activities of IFtoMM.

So, where is the core of modern MMS? In my opinion, this core is the classical discipline of kinematics and dynamics of machines. Will this discipline be relevant to 21st-century technology? I have no doubt. This discipline has favored major developments in robotics. Thanks to it we are no longer scared by the nonlinearities involved in the kinematic relations between joint and Cartesian variables in manipulators, whether of the serial or of the parallel type. Freudenstein's Mount Everest of kinematics problems, the inverse kinematics of an arbitrary six-revolute manipulator, was conquered in the eighties thanks to the methods of the discipline. The problem pertaining to the forward kinematics of parallel manipulators of the platform type was equally mastered in the nineties. This achievement was due in great part thanks to concepts developed by geometers at the turn of the century, indeed, but also thanks to advances in computational kinematics, a development of the eighties at the core of TMM, or MMS, as we want to call it now. Citing similar results in the case of machine dynamics would just make this message unnecessarily long.

But the actual challenge that lies ahead is not the survival of IFToMM; it is the survival of humankind: October 1999 saw the world population attain the terrifying figure of six billion people, who have to be fed, moved, dressed, healed, and educated. I am quite sure that MMS, and IFToMM with it, will have a major role to play here. What this role will be depends entirely on us as individuals and as a community of theoreticians, educators, and practitioners of MMS.

In the department of membership, it is my great pleasure to report that we have grown to a strong 45 Committee Members distributed throughout the world. The work ahead is still enormous, for we have only two Latin American Committee Members, Mexico and Brazil. No other Latin American Committee has expressed any interest in joining IFToMM. Does this mean that Mechanism and Machine Science is not a major technological activity in Latin America? Personally, I doubt it. Here, I must admit that I intended to promote IFToMM in Latin America during my tenure, but besides attendance to the Iberoamerican Congress of Mechanical Engineering in Havana in September 1997, where I made a pitch for IFToMM, I could not do much else. As Past-President I will put Latin America as No. 1 in my agenda.

Another region that escapes to us is Africa. We don't have a single African Committee in IFToMM. Why is this so? We were lucky enough to have had one participant from South Africa in the 10th World Congress, who offered to promote IFToMM in his country. There is a good chance of having South Africa as a Member Committee in the near future, for, additionally, we have noticed a steady publication activity in Mechanism and Machine Theory, with papers by South African authors.

I tried to give you a summary of the main issues that have kept me busy during the past four years and some thoughts on the work ahead. My four-year tenure culminated, I could say, with the celebration of the 10th World Congress and the Nineth General Asembly, which brought along a smooth transition to the next four years. Without the effective work of the Organizing Committee of the 10th World Congress, mainly Prof. Tatu Leinonen and his excellent team, these events could have not been possible. I take the opportunity to thank them all on this occasion.

But the culmination of my job is not the end of it. I am still hoping to produce a report on the state of the art of MMS as soon as I have input from all those involved in what I call the TMM21 Task Force. A major report in this regard will come in the form of Proceedings of the International Symposium on the History of Machines and Mechanisms, organized by Prof. Marco Ceccarelli, of the University of Cassino, Italy, on May 4--6, 2000. For further details on TMM21, please visit

I also take the opportunity to wish Prof. Kenneth J. Waldron, President-Elect, and his new Executive Council a fruitful and exciting term in the four years to come.

In closing, I wish you all happy holidays and all the best in 2000.

Jorge Angeles, President

President-Elect's Message

It is a pleasure to greet my colleagues around the world as the incoming president of IFToMM. As always, we face many challenges. I believe we have work to do on the structure of the organization itself to widen participation, involve younger people more, and better represent the interests of the professional community that IFToMM serves. I expect to go to the first meeting of the new Executive Council next year with a plan to achieve at least several of these objectives.

IFToMM is different in character from the technical societies most of us have in our own countries. The unit of membership in IFToMM is an organization representing a professional community. In many, but not all cases these are national communities. The IFToMM structure is really set up to bind together these organizations into an international entity. Of course, the organizations are as diverse as the communities they represent. They range from huge, powerful entities like ASME to small groups of individuals who band together to contribute the IFToMM dues out of their own pockets. It is an enormous challenge to adequately serve the interests of these disparate entities. Some long-established professional societies are seeking to internationalize themselves. However, IFToMM serves the community in ways that those organizations cannot, simply by having a balance among the member organizations, rather than the center being the originating professional society with international member communities represented only by relatively tiny branches. It is our challenge to work with the communities whose internal organizations are not well established. We must help to strengthen those organizations because the health and survival of IFToMM depends on them. At the same time we must work with the strong professional societies, and preserve IFToMM's unique role as a connection between them. Of course, this means we must be vigilant about possible infringements by newly internationalized societies.

Organizations like IFToMM are really about communication. It is about allowing groups with common interests in mechanics of machines throughout the world to feel part of a larger community. That communication takes many forms. One form is via our archival journal, Mechanism and Machine Theory. Another is via the many technical meetings and conferences sponsored by the various technical committees and permanent commissions. There are other, less formal means of communication, including meetings of the committees themselves, and, not least, this newsletter. As we all know, the technological means of communication are advancing, changing the media we have available to us. This is of great importance to an organization like IFToMM that serves professional communities distributed all over the globe. I encourage our committees and commissions to experiment with communication using the Internet and other new communication technologies.

Our technical field is also constantly changing. In the recent past, many universities throughout the world have abandoned traditional courses in theory of machines and mechanisms. On the other hand, new fields, such as mechatronics and micromechanisms are blossoming. Let us ensure that our organizational view recognizes these changes, and moves with them. That doesn't mean we should abandon traditional fields that still have important developments to offer the world. It does mean we should be quick to recognize new fields of opportunity, and to encourage the practitioners in those fields.

I thank you all for the confidence you have placed in me by electing me, and look forward to serving the members of IFToMM.

Kenneth J. Waldron, President-Elect

Message from the Editor

Dear Friends:

The year 1999 was special because it is one of those that come with the periodicity of leap years, although in a more regular fashion. Indeed, we had the 10th World Congress and Ninth General Assembly, besides the 32nd Meeting of the Executive Council, all of which took place in Oulu, Finland. You will find in this issue accounts from the Secretary-General on these events.

One item to be highlighted here, because it pertains to the editorial work behind the publication of the Newsletter, is the constitutional reform submitted by the President to the Constitution Committee, in a package of reforms. Under these reforms, the current PC Conferences is to change to PC Communications, with a broader mandate: to compile, maintain, and update information on all IFToMM activites and to spread this information to the community at large by means of a Newsletter and a Home Page. If this reform is adopted, the production of the Newsletter will be eased and its survival will not be made dependent on the good will of individuals.

So far, the production of the Newsletter has been in the hands of a group of volunteers: the Editor and the translators, besides the technical suppport from the Associate Editor and the Web Engineer. This time we have a Co-Editor, Prof. William Goodwine, of Notre Dame University, USA. Welcome onboard, Bill!

While the Editor and the Associate Editor have worked together since the Vol. 1, No. 1 issue, the first Web Engineer was hired only in 1996. Dr. Thierry Baron, then on a postdoctoral appointment at McGill University's Centre for Intelligent Machines (CIM), was instrumental in setting up the Home Page. Unfortunately, we lost Thierry to private industry in early 1998, for he decided then to start his own consulting company, with a great success, we may add. We were lucky enough to find in Mr. Pierre Montagnier, a Ph.D. candidate at CIM, a willing and competent replacement for Thierry, but only after having given it a try with a temporary replacement, who unfortunately could not devote enough time to this job. Pierre's job has been quite challenging, for he has had to figure out ways of posting a mixture of LaTeX and TeX files in the appropriate format on the Web Page, with the latter being in AMS Cyrillic (plain) TeX--ASM is the American Mathematical Society--that we need for the Russian version. One way that we had figured out that should work in the production of Vol. 7 was to post the Russian version as a picture, but the outcome was not practical, because it imposed unusually long downloading times for those readers in remote locations. This time we have done a bit of research and found that a possibility will be to produce the Russian version for the Web site after passing through Russian Word.

A major issue for the PC Communications will be to settle on a unique piece of software that will be convenient to everybody both in the Commission and to our readership. The attractive of LaTeX lies in the ease of transmission of ASCII files, but we have many readers who send us Word files, besides having a problem with the transcription of Cyrillic TeX into html for the Web Page.

The reason why I am telling you this story is to ask you to be patient and bear with us while the PC Communications settles on the most practical way of producing the Newsletter. We have received complaints from readers who are annoyed by the problems they have found when trying to download our files. Sometimes finding the source of the problem is not simple, even for professionals. We are relying on enthusiastic and competent people, but cannot afford resorting to professional services to do it on-demand at the time the problem occurs!

I take the opportunity to thank all those who have contributed to the production of the Newsletter since Vol. 1, starting with Ms. Irène Cartier, the Associate Editor, and our translators, Prof. Christoph Woernle into German and Dr. Jean-Pierre Merlet into French. The Russian translation has been mostly in the hands of Ms. Svetlana Ostrovskaya, a Ph.D. candidate at CIM, who has formed a team now to help her with language and software issues: Drs. Leonid Slutski, a Research Engineer at CIM, and Alexei Morozov, a Visiting Fellow at CIM, from IMash, the Moscow-based Institute for Machinery Research, of the Russian Academy of Sciences. Setting up the environment for the merging of files in different languages so as to produce a printed version in a layout comfortable to read, in two columns, was only possible with the unique technical capabilities of CIM's Software Engineer Mike Parker ( CIM's System Administrator Jan Binder is to be acknowledged for the smooth operation of the CIM system, the depository of the IFToMM Home Page.

Besides the regular entries in this issue, the readers will find updated lists of conferences, and, very importantly, of the new Executive Council. The Home Page includes, for the first time, a comprehensive mailing list of PCs and TCs.

To close, may I wish you all happy holidays and all the best in Y2K!

Jorge Angeles, Editor

Highlights of the 32nd Meeting of the EC

The Secretary General, Prof. Tatu Leinonen, reported that, besides the routine items--reporting from Chairs of TCs and PCs, budget discussion, and so on--the main issues were those submitted to the Ninth General Assembly, as per the entry below. The Secretary General was glad to report that all PC and TC Chairs but one--TC Rotordynamics--submitted their report, with all PCs and TCs displaying a lively activity.

Highlights of the Ninth General Assembly The IFToMM Ninth General Assembly was held on June 23, 1999 in Oulu, Finland. Chief Delegates from 37 member committees were present and eight absent. Based on the results of a postal ballot, the committees of Armenia, Georgia, Greece, Korea, Pakistan, Singapore, and Ukraine had been provisorily admitted as members in the 1997-1999 EC meetings. All seven memberships were confirmed by this General Assembly. Including these new members, IFToMM has now 45 member committees all over the world. Also at the General Assembly, the election of the Executive council for the term, January 1, 2000 through December 31, 2003 was held. The new Executive Council is listed below: Officers: President: Kenneth J. Waldron (USA) Vice-President: Jean-Claude Guinot (France) Secretary General: Tatu Leinonen (Finland) Treasurer: Robert Bicker (U.K.) Members: Manfred Hiller (Germany) Tian Huang (China-Beijing) Krzystof Kedzior (Poland) Hirofumi Miura (Japan) Alberto Rovetta (Italy) Gabor Stepan (Hungary) Adam Morecki (Poland), Jack Philips (Australia), Bernard Roth (USA), and Konstantin V. Frolov (Russia) were awarded Honorary Memberships. Distinguished Service Awards were given to Gerhard Bögelsack (Germany), Ladislav Pust (Czech Republic), Karl Wohlhart (Austria), and Pavel Lebedev (Russia). The new Constitution and Nomination Committees were elected: Constitution Committee (2000-2003): Jorge Angeles (Chair) Huirong Meng (China-Beijing) Ladislav Pust (Czech Republic) J.S. Rao (India) Terry Shoup (USA) Nominating Committee (2000 - 2003): Jorge Angeles (Chair) Joseph Davidson (USA Elizabeth Filemon (Hungary) Hong Sen Yan (China-Taipei) The General Assembly also decided that the 11th World Congress on TMM will be held in Tianjin, China on June 24, 2003. Two additional bids, from India and France, were submitted to the General Assembly, the vote being in favor of Tianjin, China. Tatu Leinonen Secretary General

Change of the Guard

The TC Rotordynamics just informed the EC of its meeting in Darmstadt on September 8th, during the IFToMM Rotordynamics Conference (September 7-10), in which the TC decided to appoint a new Chair. The appointed Chair is Dr. Neville F. Rieger, of STI Technologies, Inc. (USA), who will be replacing Prof. Giorgio Diana (Italy.) Until the EC confirms this appointment, Dr. Rieger, who has served the TC Rotordynamics as its Secretary, will be serving as Acting Chair of the Committee. Let us give a warm welcome to Dr. Rieger in his new position, with our best wishes for a fruitful and enjoyable term!

It is noteworthy that, with Dr. Rieger's appointment, we now have two representatives from industry at the chair of TCs, the other one being Dr. Miroslav Vaclavík, of the Research Institute for Textile Machines (Czech Republic.) Besides, the Chair of the PC Standardization of Terminology also comes from industry. Dr. Eng. Theodor Gh. Ionescu is affiliated with the Romanian State Railways. More industry representatives would help enhance our image as realizers, not only as thinkers!

Constitutional Reforms

In his Report to the Ninth General Assembly in Oulu, on June 23rd, 1999, the Chair of the Constitution Committee, Prof. Giovanni Bianchi, asked the Chairs of all Member Committees, TCs, PCs, and other committees to submit their views on the reforms summarized in that report. The reforms were proposed by the IFToMM President in a package circulated to all those Chairs as well as to the Past Presidents. The same reforms were studied by the Constitution Committee and amended prior to being submitted to the GA by Prof. Bianchi, who asked the audience to submit their views to him by July 31, 1999 to his postal address at CISM, to his fax, or to his E-mail address. Prof. Angeles, additionally, broadcast an E-mail message, on July 20th, to all those concerned to remind them of Prof. Bianchi's deadline.

Following that round of consultation, Prof. Bianchi would propose a new version of the Constitution and By-Laws, which would be sent out by Prof. Leinonen, Secretary General, to all the above-mentioned individuals, by September 30, 1999, along with a ballot to cast a vote. Professor Bianchi just reported that this action has not as yet taken place, mostly because of the poor reaction received. Nevertheless, the Constitution Committee must do its job, and decided to circulate, via Prof. Leinonen's office, the new version of the Constitution by November 30, 1999. The timetable to complete the democratic consultation process has thus been revised.

In setting up the new timetable, we must observe item No. 6.1 of the By-Laws, which states that ``counting of votes received shall not take place earlier than three months from the date of mailing of the ballot.'' The counting of ballots, therefore, will take place soon after February 28, 2000.

For quick reference, we include below Prof. Bianchi's address:

Secretary General
Palazzo del Torso
Piazza Garibaldi, 18
I-3310 UDINE
Tel. 39 0432 248511
Fax: 30 0432 248550

Report on the Tenth World Congress

The Tenth World Congress on the Theory of Machines and Mechanisms, held on June 21-24, 1999 in Oulu, Finland, has been notably successful. 801 abstracts were submitted to the Organizing Committee by IFToMM member committees or individuals. The abstracts were first reviewed by the member committees. Finally, 670 papers were forwarded to the OC and evaluated by the IFToMM Technical Committees or Permanent Commissions. The papers on topics not relevant to the Technical Committees were evaluated by international experts. 508 papers were accepted to be presented orally and 116 papers as posters.

There were 464 participants and 36 accompanying persons from 45 countries in the congress.

The papers presented in the congress are published in seven books in congress proceedings. This diverse collection of technical papers will doubtless constitute an important contribution to the world literature on mechanism and machine theory. The organizers hope that this collection and the discussions held in the congress under the Midnight Sun will promote the progress of the science and its application in practical engineering to build a better future for everybody.

Prof. Tatu Leinonen
Congress Chairman

Yugoslav-German Collaboration

The Academic Council of the University of Nis, FR Yugoslavia, upon the proposal made by the Academic Council of the Faculty of Mechanical Engineering of Nis, awarded an honorary doctorate of the University of Nis to Dr. Gerhard Bögelsack, Professor of the Faculty of Mechanical Engineering of the Technical University of Ilmenau, Federal Republic of Germany, in recognition of his exceptional contribution to the development of science in the field of Theory of Machines and Mechanisms and to the affirmation of the University of Nis.

Professor Bögelsack is the creator of the cooperation between the University of Nis and the Technical University of Ilmenau, initiated during the Third World Congress on the Theory of Machines and Mechanisms, in Kupari, SFR Yugoslavia, in 1971. The following year Professor Bögelsack, together with Professor Zivota Zivkovic, drafted the curriculum of the postgraduate studies in the field of Precision Engineering at the Faculty of Mechanical Engineering of Nis. Besides, Prof. Bögelsack has given lectures and seminars, and attended examinations for fifteen years (1974-1989) at the same Faculty. He has been thesis director and a member of many doctoral committees.

Professor Bögelsack contributed to the development of some specific fields of the Theory of Machines and Mechanism at the Faculty of Mechanical Engineering of Nis (indexing mechanisms, screw mechanisms, robotics, manipulators and grippers). The cooperation between the University of Nis and the Technical University of Ilmenau led to numerous joint conference and journal papers. Professor Bögelsack was an initiator and an organizer of two international symposia, in the field of precision engineering, held in Nis.

Since 1985 Professor Bögelsack has been a member of the Editorial Board of Facta Universitatis, a journal published by the University of Nis.

Professor Dr. Nenad Pavlovic, Vice-Dean
Faculty of Mechanical Engineering
University of Nis, FR Yugoslavia

De Re Historiae

On the Meaning of TMM Over Time

TMM (Theory of Machines and Mechanisms) is often misunderstood even within the IFToMM community, although it is recognized as the discipline of Mechanical Engineering related to mechanisms and machines. In this note, we try to clarify the meaning of TMM by looking at the meaning of the word over time through few definitions by recognized authors:

  • M. Vitruvio (1st century B.C.), wrote in De Architectura, liber X, translated and discussed by Daniele Barbaro in Venice, 1584: ``A machine is a combination of materials and components that have the capability of moving weights.''
  • Galileo Galieli wrote in Le Macchine, 1593, reprinted in Opere di Galileo Galilei, edited by F. Brunetti, Turin 1964: ``A machine is a means by which a given weight will be transported to a given location by using a given force.''
  • Paolo Branca, in Le Macchine, Rome, 1629, described machines by stressing features of their operation: it is based on motor power, it incurs a cost, and is dependent on operator's skills.
  • J. Leupold, in Theatrum Machinarum, Leipzig, 1724, treated the description of machines and mechanisms referring to ``their aim of modifying motion.''
  • P. Lanz and A. Bétancourt's Essai sur la composition des machines, Paris, 1808: ``In agreement with M. Monge, we consider as elements of machines the devices than can change the direction of motion ... the most complicated machines are only combinations of those capable of simple motions''.
  • Robert Willis' Principles of Mechanism, London, 1841 (1870 - 2nd Ed.): ``I have employed the term Mechanisms as applying to combinations of machinery solely when considered as governing the relations of motion. Machinery as modifier of force.''
  • C.I. Giulio's Lezioni di meccanica applicata alle arti, Turin, 1846: ``We name as machine any device which is aimed to receive the action of a motor and modify velocity and direction of the motion obtained.''
  • F. Releaux's Theorethische Kinematik,
    Braunschweig, 1875: ``A machine is a combination of bodies capable of withstanding deformation, so arranged as to constrain the (mechanical) forces of nature to produce a prescribed effect in response to prescribed input motions.''
  • F. Masi's Teoria dei meccanismi, 1897, Bologna: ``Hence we name mechanism a kinematic chain that has been fixed on one of its components; machine a mechanism whose components make mechanical work.''
  • G. Königs' Introduction à une théorie nouvelle des mécanismes, Paris, 1905: ``A machine is recognized as an assembly of resistent bodies that are constrained reciprocally and are under the action of natural forces. If forces are asbtracted, the remaining of a machine consists of bodies and constraints. This is a mechanism''.
  • R. S. Hartenberg and J. Denavit's Kinematic Synthesis of Linkages, New York, 1964: ``The term machine is associated with the use and transformation of force, and although motion in varying degrees is encountered in a machine, the idea of force dominates. Mechanism, on the other hand, definitely conjures up the idea of motion, and while forces do exist, they are relatively small and unimportant compared with the exploitation of motion.''

Finally, the meaning of the word ``theory'' needs further explanation. The Greek word for Theory comes from the corresponding verb, whose main semantic meaning is related with examination and observation of existing phenomena. Even in its classical meaning the word theory includes practical aspects of observation as experiencing the reality of phenomena, so that theory means also the application of results from analysis. In fact, this last meaning is what was included in the discipline of modern TMM as Monge established it at Ecole Polytechnique at the beginning of the XIX Century (see, for example, the book by Lanz and Betancourt, including synthesis procedures).

In conclusion, the modern meaning of TMM is that of a discipline that treats both analysis and synthesis of mechanisms and machines. This meaning will remain in the future, since we shall always have mechanical devices related with the life and work of human beings. These mechanical devices need to be designed and enhanced with approaches from mechanical engineering because of the mechanical reality of the environment where human beings will always live, although new technologies will substitute some components or facilitate the operation of mechanical devices!

In fact, the IFToMM Terminology, published in Mechanism and Machine Theory in 1991 (Editor's Note: Vol. 26, No. 5, p. 436.) states:

  • Machine: mechanical system that performs a specific task, such as the forming of material, and the transference and transformation of motion and force.
  • Mechanism: system of bodies designed to convert motions of, and forces on, one or several bodies into constrained motions of, and forces on, other bodies.

Marco Ceccarelli
Chair, PC History of TMM
University of Cassino, Italy

Comments of the Editor to the Above Discussion

The above definitions exclude computers as legitimate machines. Even IFToMM's definition leaves computers out. Additionally, IFToMM's definition of mechanism is rather convoluted and needs straightening. A more inclusive definition of machine is given in Frolov et al. [Frolov, K. V. (editor), 1987, Teoriya mechanismov i machin (Theory of Mechanisms and Machines), Vyschaya Shkola, Moscow (in Russian)]: An apparatus for transformation of power, materials, and information to substitute or simplify physical or intellectual work.

Along the same lines, Nilsson (Nilsson, N.J., 1999, Artificial Intelligence: A New Synthesis, Morgan Kaufman Publishers, Inc., San Francisco. p. 2) states: ``To many people, a machine is a rather stolid thing. The word evokes images of gears grinding, steam hissing, and steel parts clanking... Nowadays, however, the computer has greatly expanded our notion of what a machine can be.''


We are still a long way from producing a report of the state of the art in machine and mechanism science in the XX Century, with a vision for the evolution of our discipline in the XXI Century. An important report along these lines has been received from Prof. Jürgen Schönherr, TU Chemnitz, Germany. While Prof. Schönherr's whole report is available at the IFToMM Home Page: 

under link ``TMM21,'' and will be an integral part of the TMM21 Report, a summary is included here both in English and German, for Prof. Schönherr submitted it in these two languages. We encourage our readers at large, especially those listed in the TMM21 Task Force, to submit their views on these issues.

Jorge Angeles
IFToMM President

TMM in Germany-Summary

Compared to other countries, TMM in Germany is highly applications-oriented and closely related to industrial practice. This is, not least, due to the high level of development of mechanical engineering in this country, in particular in the processing-machine manufacturing sector. The lack of practical orientation and the academic isolation of TMM, which are often criticized in other countries, especially in the United States, can hardly be found in Germany. A number of German universities offer future machine and device designers curricula which pay appropriate attention to the study of the Theory of Machines and Mechanisms. The courses emphasize teaching of geometrical and applications-oriented methods which allow the synthesis of mechanisms required in industrial applications. This approach differs from the more analytical nature of Applied Mechanics. In the 21st century, mechanisms will continue to be essential for generating periodic motions in those applications where high forces are to be transmitted at high working speeds and where the motion to be generated remains constant for a sufficiently long period of time. Contrary to the present-day tendency of developing decentralized drives, mixed drives consisting of mechanisms and controlled drives will be increasingly developed in the future for the purpose of ensuring a certain level of part flexibility. The synthesis of such mechatronic motion-generating systems (a.k.a. adjustable mechanisms, which are supplied with sensors and suitable control electronic systems, and are characterized by a high level of adaptability) requires an improved interdisciplinary cooperation between researchers in the fields of mechanical engineering, electrical engineering, and computer science.

Information technology alters the technical character of machines and devices and creates a completely new working environment with which mechanical designers from industry will have to cope. While computer programs for geometric design and those for the kinematic and dynamic simulation of mechanical and mechatronic systems have reached a high level of sophistication, programs available in the field of kinematic design are highly specialized and can be used by a limited number of experts only. The integration of user-friendly modules for performing type synthesis, type description and dimensioning of mechanisms in CAD systems should be an essential element of future research and development efforts. This work should not only apply the well-known methods used in kinematic geometry and optimization, but also develop and use computer-oriented methods, including those developed in artificial intelligence.

As TMM meets the challenges of computer technology and uses advanced mathematical and computer-aided methods and turns to new objects, including those of mechatronics, microtechnology and biomechanics, as well as to integrated methods of investigation, TMM will be able to keep its place and even gain importance in the next century. However, the vanishing of borders between the various areas of expertise should not lead to essential teaching and research contents being abandoned, and systematic and mathematical methods being insufficiently investigated and taught in engineering courses, for the sake of using a system-oriented approach at any price. Being open to interdisciplinary research work without giving up one's own scientific profile is the main challenge to be faced by those committed to the Theory of Machines and Mechanisms and any other classical engineering disciplines in the XXI Century.

J. Schönherr, Chemnitz, May 1999

TMM in Deutschland-Resümee und Ausblick

Die Getriebetechnik in Deutschland hat, im internationalen Vergleich, einen ausgeprägt anwendungsorientierten Charakter und einen starken Bezug zur industriellen Praxis, der nicht zuletzt aus dem hohen Stand des deutschen Maschinenbaus, speziell des Verarbeitungsmaschinenbaus, resultiert. Die in anderen Ländern und speziell in den USA beklagte Praxisferne und akademische Isoliertheit des Faches TMM ist in Deutschland kaum festzustellen. Im Programm der universitären Ausbildung eines Maschinen- oder Gerätekonstrukteurs findet die Getriebetechnik, vor allem wegen ihrer weitgehend objektbezogenen und synthetischen, geometrisch-anschaulichen Methodik, durch die sie sich von der mehr analytischen Vorgehensweise der Technischen Mechanik abgrenzt, an einigen deutschen Universitäten ihren angemessenen Platz. Zwangläufige Mechanismen werden auch im 21. Jahrhundert ihre Bedeutung für die Erzeugung periodischer Bewegungen vor allem dort behalten, wo, bei hoher Arbeitsgeschwindigkeit, hohe Kräfte zu übertragen sind und die Bewegungsaufgabe in einem genügend großen Zeitabschnitt konstant bleibt. Entgegen dem jetzigen Trend der Entwicklung dezentraler Antriebe werden sich, zum Gewährleisten einer bestimmten Teilflexibilität, mehr und mehr Mischformen aus Mechanismen und gesteuerten Antrieben durchsetzen. Die Entwicklung dieser mechatronischen Bewegungssysteme, die auch als Verstellgetriebe bezeichnet werden, und die, unter Einbeziehen von Sensoren sowie einer entsprechenden Regelungselektronik, einen hohen Grad an Adaptivität besitzen werden, erfordert, wie schon oben bemerkt wurde, zunehmend die interdisziplinäre Zusammenarbeit des Maschinenbaus, der Elektrotechnik, der Elektronik und der Computerwissenschaften. So wie die Informationstechnologie den technischen Charakter von Maschinen und Geräten verändert, hat sie ein völlig neues Umfeld des Konstrukteurs geschaffen. Während Computerprogramme für das geometrische Design einerseits und für die kinematische und dynamische Simulation mechanischer und mechatronischer Bewegungssysteme andererseits bereits einen hohen Stand haben, existieren auf dem Gebiet des kinematischen Designs nur spezielle und von wenigen Experten zu benutzende Programme. Die Integration von nutzerfreundlichen Bausteinen zur Struktursynthese, Strukturbeschreibung und Maßbestimmung von Mechanismen in CAD-Systeme muß einen Schwerpunkt zukünftiger Forschung und Entwicklung bilden. Dabei sollten, neben bekannten Methoden der kinematischen Geometrie und Optimierung, computerorientierte Verfahren wie z.B. der Künstlichen Intelligenz entwickelt und genutzt werden. In dem Maße, wie die Getriebetechnik den Herausforderungen der Computertechnologie gerecht wird, sich moderner mathematischer und rechnergestützter Methoden bedient und neuen Objekten, z.B. der Mechatronik, Mikrotechnik und Biomechanik, und integrierenden Betrachtungsweisen zuwendet, wird sie ihre Bedeutung im nächsten Jahrhundert behalten oder ausbauen. Das Auflösen der Grenzen zwischen einzelnen Disziplinen darf aber nicht dazu führen, daß in Lehre und Forschung wichtige Inhalte aufgegeben und, zugunsten einer Systembetrachtung um jeden Preis, systematische und mathematische Methoden zu wenig untersucht und im Studium immer weniger vermittelt und trainiert werden. Sich interdisziplinärem Denken zu öffnen, ohne das eigene wissenschaftliche Profil zu verlieren, darin liegt eine Herausforderung des 21. Jahrhunderts für die Getriebetechnik wie für jede klassische Technikwissenschaft.

J. Schönherr, Chemnitz, Mai 1999

Letter From Singapore

Jorge Angeles, on a 12-month sabbatical at Singapore's Nanyang Technological University (NTU), sends his first impresions of this experience:

Singapore is one of the youngest countries in the world, having celebrated its 34th anniversary last August. It is thus not surprising that NTU is so young, for it was established in 1991, out of the now defunct Nanyang Technological Institute (NTI). While still operating as NTI, the institution initiated its research activity in 1986, with one research student and one research project. Thanks to research funds received from the Minister of Education and the National Science and Technology Board, among others, the research activity at NTU has grown at an impressive pace, with 946 research papers published in 1998.

NTU's mission is to promote industrial R&D in Singapore, which includes not only its technological infrastructure, but also the training of highly-qualified manpower. One focus of engineering education at NTU, in line with the Singapore approach, is the education of entrepreneurs of high-tech activities. Singapore has even come up with a newly coined word, technopreneurship, to describe the spirit that it intends to promote. Along the lines of contributions to the English language, the Singapore government has now enriched its vocabulary with a neologism: heartware. By heartware, the government means the infrastructure required to implement its plans for the next few years, with a gentler, kinder approach to people.

To develop the skills required by technopreneurship, Singapore counts on two universities and various vocational schools. NTU's older sister is the National University of Singapore, with undergraduate and graduate programs in engineering, science, humanities, and medicine. Singapore is best known abroad for its financial infrastructure and its economic dynamism. It is less known as a glamorous city-state with a record number of eateries per person. Given the multiethnic character of its population, reflected in its four official languages--English, Hindi, Malay, and Mandarin--it comes as no surprise that Singapore offers a uniquely rich variety of cuisines proper of the region. For the western visitor missing North American and European dishes, Singapore also offers a host of Tex-Mex, Mexican, Californian, Italian, and French restaurants within the broadest price spectrum. In fact, eating is something that the local population takes very seriously. This is reflected in the number of canteens with which NTU counts: For a student population of about 18,000, this visitor has counted not less than 12 canteens, each with a seating capacity of a couple of hundred places. Since each canteen offers a variety of cuisines, it is no exaggeration to say that it will take a couple of months to explore the whole variety of dishes offered by the canteens at the most affordable prices. A regular meal, with a soft drink included, can cost a mere S$3.40, which, at the rate of S$1.70 per US Dollar, means that you can get a good meal for just $2.00 US Dlls. All in all, the Singapore experience is exciting and highly recommendable.

Books and Theses

Basics of Robotics: Theory and Components of Manipulators and Robots

Morecki, A. and Knapczyk, J. (editors), CISM Courses and Lectures No. 402, International Centre for Mechanical Sciences, 1999, Springer-Verlag, Vienna.

The book includes chapters from five authors: Miroslaw Galicki; Jozef Knapczyk; Adam Morecki; Antoni Wilinski; and Teresa Zielinska.

Part I includes seven chapters, in which the basic concepts, definitions, and classification of manipulators and robots are introduced. Methods of solution of direct and inverse kinematics are discussed. Next, statics and dynamics of manipulators are studied using the principle of virtual work and the Newton-Euler and Lagrangian approaches. The last two chapters include selected problems of motion planning and parallel-manipulator design. Part II includes three chapters in which the methodology of gripper selection, design principles of industrial robot grippers and drives, motion transmission mechanisms, sensors and transducers is discussed. Part III deals with problems of motion control and methods of task planning. Part IV introduces different types of robots: manipulators for underwater operations; industrial robots; robots for rehabilitation; and elastic manipulators, including the elephant trunk and spinal-type manipulators. Design and control issues are discussed. The chapter dedicated to walking machines describes briefly their historical development and control methods. Current research trends are summarized, the last chapter being devoted to microrobotics and its possible applications.

Robot Analysis: The Mechanics of Serial and Parallel Manipulators

Tsai, L.-W., John Wiley & Sons, Inc., 1999, New York.

This book provides the fundamental knowledge needed for understanding the kinematics, statics, and dynamics of both serial and parallel manipulators. Each chapter contains numerous worked examples and problems to reinforce learning. An extensive reference list at the end of each chapter is included to provide readers with plenty of resources for more advanced study. In addition, the book also features chapters on wrist mechanisms and tendon-driven manipulators. An overview of the state of the art in solving systems of nonlinear equations that arise in robot kinematics is given in the appendices. Robot Analysis is a text for upper-level undergraduate and graduate students in mechanical engineering, electrical engineering, and computer science, as well as a desktop reference for robotics researchers working in industry and government laboratories.

The Beauty of Ancient Chinese Locks (in Chinese)

Yan, H.-S., Ancient Chinese Machinery Cultural Foundation, Tainan, Taiwan, 1999.

In the year 1978 when I studied in Purdue University, USA, my advisor, Professor Allen S. Hall Jr. showed me more than one hundred scales of different kinds that he had collected. That incident inspired me greatly and the idea of having a collection of my own planted a seed in my mind. Although I was not quite sure what it might be, I knew it had to meet the following five requirements: First, it had to be a device that adapted well to my specialty. Second, it had to deal with the culture of Taiwan, so that a profound and specific research would be possible and significant. Third, it should not be too large in size, or there would never be enough room to keep it. Fourth, it must not be too expensive so that I would be able to afford it. And, fifth, it should not be too large in quantity, lest the characteristics be insignificant.

One day at dusk in 1986, I happened to find a shabby, old copper lock at a vendor stall near the Taipei Railway Station. The moment I saw it the wandering mind came to a decision: yes, ancient Chinese locks served well as the theme of my ideal collection. Ever since that day, I have visited quite a number of museums, antique shops, flea markets, second-hand merchandise stores, trying to find as many types of ancient locks as possible. Now I have more than 500 pieces in my collection.

The true value of a collection lies in the appreciation, research and discoveries of the object, not merely through purchase and preservation. Therefore, I have devoted myself, for years, to doing research on ancient locks. Not only have I visited many museums all over the world to see the exhibitions of ancient locks, but I've also buried myself in the piles of books found in the libraries. I found that the introduction, exhibition and documentation of western locks, though not large in quantity, has integrity and organization. Much contrary to that, information on the exhibitions and preservation of ancient Chinese locks is sparse and incomplete. Additionally, any documents or texts on the historical development or any introduction to the characteristics of the ancient Chinese locks are difficult to find. That instilled enough courage in me to start working on this book, much aware of my limited talents and capability.

The publication of this book aims not only to introduce the development and characteristics of ancient Chinese locks based on my collection and research for more than a decade; it also demonstrates the beauty of ancient Chinese locks. Moreover, the book is part of the preparation for the establishment of ``The Museum of Ancient Locks,'' with the hope of presenting a more solid and complete collection to the public.

I dedicate this book to the late Professor Allen S. Hall, Jr., who educated me and inspired me in so many ways.

Hong-Sen Yan
Tainan, Taiwan

Paradigmes parallèles appliqués au calcul de la dynamique non linéaire des mécanismes flexibles

Danielle Coulon, Université de Liège, 1998, Thèse de doctorat.

L'analyse des mécanismes flexibles est une discipline qui s'est développée récemment et dont les applications se retrouvent dans des domaines aussi variés que le domaine spatial, l'aéronautique, la robotique ou la dynamique des véhicules. Elle nécessite des ressources de calcul importantes non pas uniquement par la taille des modèles comme en analyse linéaire où les systèmes atteignent de nos jours fréquemment un million d'équations, mais aussi par la complexité des phénomènes étudiés (non seulement la cinématique de corps rigides mais aussi la prise en compte des effets dynamiques et de la flexibilité des structures) et par la nécessité de simuler le comportement des systèmes sur de longues périodes de temps.

L'objectif principal de ce travail de recherche est de mettre en évidence et d'exploiter dans le cadre de la cinématique et de la dynamique des mécanismes flexibles, les différents niveaux de parallélisme accessibles à l'utilisateur intervenant dans des ordinateurs de type multi-processeurs à mémoire partagée, et d'adapter la formulation du problème mécanique choisi comme application.