394 Ventil 15 /2009/ 5 JUBILEJ – INTERVJU Ventil: Prof. Backé, it is a great honor for our fluid power engineering jour- nal Ventil to have an interview with you as one of the most prominent professors and experts in the field of Fluid Power worldwide. In July this year you celebrated you 80 th birthday anniversary. On behalf of the journal Ventil I would like to congratulate you on this special occassion. On 31 July 2009 there was a great event in Aachen, a special Colloquium to honor your birthday. It was an extraordinary honor for me to have been a part of this event, to which about 160 guests from Germany and abroad were invited and to celebrate it with you and your respected wife Ms. Seitz-Backé. What were your feelings on this day and what are your feelings now? Prof. Backé: First of all, thank you for your good wishes. My answer to your question is that I felt great and I am very proud that I could run the insti- tute for 26 years and reached some good results so the institute has got a better reputation in Germany and also globally. A short interview with Professor Emeritus Wolfgang Backé, Dr.-Ing. Dr. h.c. mult., former Head of IFAS of RWTH Aachen University, on the occasion of his 80 th birthday celebration in Aachen on 31 July 2009 Fluid Power Over Four Decades em. Univ.-Prof. Dr.-Ing. Dr. h.c. mult. Wolfgang Backé Ventil: You have been professor eme- ritus for fifteen years and are still active at the Institute IFAS where you were a director for 26 years. How do you see the development of the Institute nowadays? Prof. Backé: I am happy that the Insti- tute IFAS is running so well under the guidance of my successor professor Murrenhoff. But we have to realize that research in the field of fluid power has be- come more difficult today. The real important discoveries, as for example the proportional technique, the car- tridge technique, the displacement control technique and the secondary control was introduced and much research has already been done in this field. So, today the research is much more directed to a deeper knowledge of materials, hydrodynamics, produc- tion possibilities and to a condition monitoring. Ventil: Let’s go back to the begin- ning of your career in fluid power, Prof. Backé. You earned your BSc in Mechanical Engineering at RWTH Aachen in 1955 and your PhD at the Institute of Machine Tools at RWTH Aachen in 1959. What were the rea- sons for continuing your professional career in the field of Fluid Power? Prof. Backé: From the beginning of my studies I was interested in fluid power. At that time machine tools were the main application of fluid power. We had one ingenious lec- turer who could explain fluid power very well. So the signal circuit at that time was electric but sometimes also hydraulic or pneumatic. It was fascinating how the automatic pro- cedures went on, only controlled by the electric or fluid power switches. Ventil: After spending some years at another university and in the industry, you rejoined RWTH Aachen in 1968 and established the Institute for Hy- draulics and Pneumatics (IHP), today known as the Institute for Fluid Power Drives and Controls (IFAS). What were the reasons for such a step? Prof. Backé: I think that in the field of fluid power a few years of industrial experience are necessary because fluid power is quite related to an application. But I thought that in this field a lot of systematic work The fi rst building of the Institute for Hydraulics and Pneumatics (1968 – 1972) 395 Ventil 15 /2009/ 5 JUBILEJ – INTERVJU was necessary. The knowledge of the fundamentals has to be taught to students who want to work in this field successfully. Ventil: Can you describe the begin- nings of the institute IHP and the main research interests in a bit more detail. How big was the Institute in the beginning? Prof. Backé: The beginning of the IHP was not easy. We were only a few people and we had nearly no mea- suring devices, so our only chance was to write intelligent applications to research funding organizations and in this way increase our man power, measuring devices and testing stands. We made systematic tests of all the available control devices and displacement units. At last we covered the whole field of fluid power. Because of our reason- able reports we earned good reputa- tion and joined research projects carried out by a group of institutes, so we worked for instance in the field of production technology, in the field of medical technique, in the field of power transmission and in the field of robotics. Ventil: Prof. Backé, after the es- tablishment of the new Institute in 1968 you spent the next 26 years as Professor and Director of Fluid Power Transmission and Control at the Faculty of Mechanical Engineer- ing. During these years your Institute became one of the world’s largest and renowned research institutes in the field of Fluid Power. How did you succeed in this and what where the main driving forces for such a success? Prof. Backé: There really were good opportunities at that time. We were the only institute that was fully work- ing on fluid power. Other universities employed experts from the industry to teach the students, but that could only give an explanation of a single application of fluid power and not the whole field. Our system of handling the whole field from the fundamen- tals to the different applications sys- tematically seems to be the right way. So other universities as Dresden, Braunschweig, Hamburg, Karlsruhe followed our system and founded special institutes for fluid power. The same is true for other countries like England, Sweden, Finland, Slovenia and Japan, to only name a few. Ventil: Well, this is probably only one of the reasons why you are called The Pope of the Fluid Power among the “Fluid Power people” all around the world. For your leader- ship and distinguished contributions to fluid power and motion control, including the establishment of one of the world’s largest and renowned research institutes in the field of fluid power, you were honored dur- ing your professional career with numerous national and international recognitions, rewards and medals like ASME medal, “Verdinstkreuz des Verdinstordens« of the Federal Republic of Germany etc. You also hold honorary doctorates from the University of Tampere, Finland, the University of Linköping, Sweden and the University of Bath, UK. You were also the honorary professor at the Technical University of Taiyuan (1981) and the Technical University of Hangzhou (1989) in China. What is the secret to your success? Prof. Backé: I have no special secrets, but I had fun working intensively on fluid power problems. Another point may be that I am very interested in special research objects, so I was a serious discussion partner to my students. We have contacts with nearly all groups working on fluid power in Germany as well as around the world. I am always happy to meet colleagues on conferences and discuss present and future developments in fluid power. Ventil: Your main activities as full and emeritus professor have also included the promotion of 122 doctorate students, to who you were “Doktor- vater”. Many of them, including my- self, came from abroad to study with you. 122 is an incredible number and achievement! Prof. Backé: It is my experience that there are excellent students in any country in the world if your institute is well known as a forge of systems and new ideas. I am proud that many of my former doctorate students hold important positions in the industry or at universities. Ventil: As your “Doktorsohn” I can confirm your special feeling for people, for their research work and especially for the novelties in the specific research field. You have The handing of the Bundesverdienstkreuzes of the Federal Republic of Ger- many by President Herzog 396 Ventil 15 /2009/ 5 JUBILEJ – INTERVJU always found the right research idea at the right time. Can you give some advice in this direction to those of us, who continue your work as university professors in the field of Fluid Power? Prof. Backé: I have always said that is very necessary that a university professor has good contacts in the in- dustry - this means to the applications - so he can hear and see what the real problems in practice are. I recom- mend that capable younger scientists should start their way as university professors to transmit and increase the knowledge of fluid power. Ventil: Your research work in Fluid Power was very rich and innovative the entire time during your profes- sional career. Besides the theoreti- cal approach you always wanted to end the research with a prototype and with experimental verification. Are there any special milestones, research fields or research achieve- ments, which seem to you as the most important in your career? Prof. Backé: The theoretical approach of the system cannot take into ac- count all the peripherical influences. Therefore in our field, near to appli- cations, it is necessary to prove the applicability of a development by ex- periments and to correct the theoreti- cal model after the test results. Such corrections by unexpected influences often happen during our tests. That is true, for instance, for different kinds of valves or displacement units. Ventil: One of your important per- sonal characteristics has always been a special feeling for the industry. You have succeeded in developing and kept it active, this, so important university-industry cooperation, not only in Germany but also with com- panies from abroad. How did you do it and what are the secrets to such a success? Prof. Backé: It takes a lot of time for an institute to get a good reputation in the industry. If the institute gets a request from a company, the com- pany must rely on the delivery of the report on time and get an accurate analysis of the results. That means that the members of the institute have to work more or less under industrial conditions. Ventil: For ma-ny years you have been the pu-blisher of the globally known journal O+P, which has been a very important source of informa- tion and research ideas for research- ers and industrial environment all over the world. Also our journal Ventil has followed it as a model. You have also started to organize a scien- tific conference AFK, now IFK and initialized and moderated numerous so called “O+P Gespraeche” – O+P discussions. All these activities prove that you have a special feeling for research and especially for the re- sponsibility to transfer this knowledge to the industry and vice versa. Prof. Backé: I think that it is an im- portant task of university institutes to spread the knowledge of their field and to stimulate innovations. For this purpose we used all the possibilities you mentioned: a journal with appli- cable and innovative articles, confe- rences and discussions. Ventil: How do you see nowadays the position and the development of fluid power in Germany and also globally? Prof. Backé: We have to realize that fluid power has got a strong competi- tor in electricity. The introduction of microelectronics in the signal path of systems has strengthened the position of fluid power. But electricity is also trying to enter the energy path of systems. Because of the lower force density, until now only low force applications have been possible. In this area, whether electric or fluid power means are used often depends on the price. But we must see that it is a tendency to use electrical systems mainly to avoid oil losses. That is the reason why the research in the sealing technique is so impor- tant. Until now there has been an increase of fluid power production in spite of the competition by elec- tric systems, but that can change if electric drives or fuel cells are further developed. Ventil: Prof. Backé, in the last few years your focus has been perhaps a bit more in pneumatics, which is becoming increasingly important and already takes almost 50% of the market in comparison to hydraulics. In your opinion, what, is the reason for such a growth and where do you see the most important advantages of pneumatics? Prof. Backé: This higher annual in- crease of pneumatics in comparison IFAS today – Main building 397 Ventil 15 /2009/ 5 JUBILEJ – INTERVJU to hydraulics is astonishing. I found that this fact does not only have one single reason but several. The main reason may be that a pneumatic system can be used anywhere: in production engineering, handling, packaging or in process engineering. There are companies which offer prefabricated components. So there is no need for the components to be designed and produced, but the user can select them out of the cata- log and build up complete systems. Furthermore, he can insert desired functions into the components: as ac- celeration and deceleration charac- teristics, speed behavior, generation of desired forces and so on. The energy costs are higher in pneu- matics but on the other side the investment and maintenance costs can be much lower. So, for a long working period the overall costs of a pneumatic system can be lower than of an electric or hydraulic drive. Ventil: What is your opinion on the future development of fluid power? Prof. Backé: I think that the devel- opment by permanent innovations will continue in the future. They will strengthen fluid power. But the inno- vations, which open wide new fields will are becoming rarer. The competi- tion with electricity will become more severe, that is sure, so it is necessary to find new applications where the special advantages of fluid power are used and are not replaceable. Until now hydraulic drives have do- minated the mobile machinery. The hydraulic high force cylinder cannot be easily replaced by an electric de- vice. But high torque electric motors can perhaps become a strong compe- tition. That is especially true if the fuel cells can one day replace the diesel engine. But that will take decades. Ventil: And the last question, Prof. Backé. What are your plans for your future professional activities? Prof. Backé: I have just moved out of my cabinet in IFAS. Combined with this is the decision to stop profes- sional activities. Young people must have the chance to gain reputation in the field of fluid power. I am still interested in publishing articles in different magazines. Anyhow, if someone asks a question, I will still try to find an adequate answer. But I am happy to have some more time to read historical books. I am mainly interested in historical de- scriptions and biographies. Events, to which I have direct personal connec- tions often attract my attention. The history of Aachen and surroundings offers many such possibilities. Ventil: Prof. Backé, in the name of our journal Ventil and in my per- sonal name I thank you very much for your answers and the time you took for us. I also wish you many fruitful activities and happy years with your wife Frau Seitz-Backé in the time to come. For journal Ventil: Niko HerakoviÏ Znanstvene in strokovne prireditve 7 th Internationales Fluidtechnisches Kolloquium – 7 th IFK – Sedmi mednarodni kolokvij o fluidni tehniki 22.–24. 03. 2010 Aachen, ZRN Organizator: – Institut für fluidtechnische Antriebe und Steuerungen Tematika: – stacionarna hidravlika – avtomatizacija in regulacija na vozilih – tribologija – delovni fluidi – simulacija – pnevmatika Informacije: – kontaktna oseba: Dipl. Ing. S. Fritz – Institut für Fluidtechnische Antriebe und Steuerun- gen, Steinbachstraße 53, D 52074 Aachen, BRD; – tel.: + 49(0) 241-8027522, e-pošta: general@ifk2010. de, internet: www.ifk2010.de BAUMA 2010 – Mednarodni sejem gradbeništva 19.–25. 04. 2010 München, ZRN Organizator: – Messe München International – VDMA Tematika: – gradbeni stroji in težka vozila – gradbeni materiali – rudarski stroji – oprema za gradbeništvo Informacije: – www.bauma.de nadaljevanje na strani 410