Plenary Lectures

/Plenary Lectures
Plenary Lectures 2022-02-10T14:40:37+00:00

The following distinguished Speakers have accepted our invitation to give a Plenary Lecture at the Symposium:

Symbiotic Fluid Power

Rudolf Scheidl

Rudolf Scheidl
Johannes Kepler University Linz

Fluid power realizes mechanical functions in a machine system. As such it is subordinate to this system and inherits the requirements from it and from the process it handles. The selected solution must provide the prescribed functionality and should minimize space, energy, maintenance, final disposal or recycling, and the efforts for proper control and comprehension by all its stakeholders.

This conventional expectation on any technical subsystem asks for a kind of ideal slave, who does a perfect job, never falls ill and needs only minimum amount of food, cloth, and place to sleep to survive. Of course, technical devices do not deserve moral concerns. But they have limitations which in some cases might be better compensated by other parts than blowing up these devices to obtain an optimized complete system. Such a helpful interaction or sharing of activities is known as symbiosis in biology.

It is obvious that an effective fluid power system is adapted to the machine system, its functions and use cases. In a functional decomposition based system design drive or actuation units may have low hierarchical rank and may inherit requirements which stem form properties of superordinate units. This may pose requirements on the sub-system, for instance, a fluid power drive, which make this having one or more disadvantages like higher complexity, cost, sensitivity, weight, construction space, or control effort, which could be avoided by to a better superordinate concept or different technological solutions of other functions. Most likely, the overall system benefits from such mutual assistance of sub-systems. Symbiotic solutions in the sense of mutual compensation of strengths and weaknesses of the sub-system technologies require sufficient expertise of all the possible technologies, for instance of fluid power. Expertise in this context is more than knowing standard solution concepts but rather being able to see the best suited concept for the particular case, which might be unconventional or novel.

Examples of such symbiotic solutions or the potential benefit of “symbiotic thinking” will be given for fluid power drives for different applications.

This talk intends to motivate the PhD candidates participating in the Symposium to become complete engineers who decisively contribute to smart overall solutions by educated contributions to the superordinate or overall design concept and by clever fluid power solutions. It is a praise of an engineering attitude which is seeking the best overall solution and the attempts to grow the competencies for getting better in accomplishing this.

Born November 11th 1953 in Scheibbs (Austria). MSc of Mechanical Engineering and Doctor of Engineering Sciences at Vienna University of Technology. Industrial research and development experience in agricultural machinery (Epple Buxbaum Werke), continuous casting technology (Voest Alpine Industrieanlagenbau), and paper mills (Voith). Since Dec. 1990 Full Professor for Mechanical Engineering at the Johannes Kepler University Linz. Research topics: hydraulic drive technology and mechatronic design.

Fluid Power – A sustainable motion technology

Katharina Schmitz
RWTH Aachen University

The consequences of a changing climate are more and more visible and affecting human kind all over the world. The reduction of greenhouse gas emissions is one of the mayor challenge for industries worldwide and is needed to be set to near zero in the next decades. In addition, manufacturing of components, systems and machines must be based on sustainable resources in the near future. Nevertheless, it is anticipated that standard of living as well as industrial production remains the same and even increases in the future. This means, more sustainable technologies are needed, allowing engineers to fulfil drive operations as required with the sustainable boundary condition as well.

Fluid power motion technology has several advantages when talking about sustainability. Nevertheless, there are weak points that need to be further addressed in research and development to make fluid power technology a key technology for a sustainable development.

The presentation gives an overview of the potential in fluid power systems in regard to an environmental friendly usable technology and aims to opening the field for further discussions about this topic.

Prof. Katharina Schmitz graduated in mechanical engineering at RWTH Aachen University in 2010 with part of her studies taking place at Carnegie Mellon University in Pittsburgh (USA) and working in Le Havre (France). After graduation, she worked as a scientific staff member and Deputy Chief Engineer at IFAS, the Institute for Fluid Power Drives and Controls of Prof. Murrenhoff. In 2015, Prof. Schmitz graduated as Dr.-Ing. and started working in the industrial sector for a family-owned company, which focuses on special purpose hydraulic solutions and large cylinders. There, she was promoted to Technical Director in 2016. Since March 2018 she is full professor at RWTH Aachen university and Director of ifas, the Institute or Fluid Power Drives and Systems. In January 2020 she took over the position as Vice Dean of the Faculty of Mechanical Engineering at RWTH Aachen.

Energy Saving Fluid Power Technology for Off-Highway Vehicles

Kim A. Stelson

Kim A. Stelson
University of Minnesota

During the oil shocks of the 1970s, the world began to seriously address the problem of fuel efficiency of passenger cars. The result has been a major improvement in fuel efficiency. During the same period, the efficiency of off-highway vehicles has changed little. There are several reasons for the lack of progress. One is the diversity of application of these vehicles which include the sectors of agriculture, construction, mining and forestry, with each of these sectors having multiple types of machines with a wide variety of duty cycles.  Power transmission in a passenger car has only one purpose, propelling the vehicle down the road. In contrast, an off-road vehicle has propulsion, steering and work circuits that all must be powered in a coordinated fashion. This makes the improvement of efficiency particularly challenging.

To improve the efficiency of off-highway vehicles, a least four improvements are required: 1) keeping the engine in an efficient operating range, 2) hybridizing the drivetrain to store and release energy, 3) minimizing power losses in the system with more efficient components and the elimination of throttling valves, and 4) controlling the system intelligently. These improvements work synergistically to increase vehicle efficiency, so that all must work together in a coordinated system for significant improvement. Further advances are possible with the integration of electrical and hydraulic systems and the use of connected and automated vehicles. This talk will present ongoing research projects aimed at significantly increasing the efficiency of off-road vehicles an outline a path toward a more efficient future.

Kim A. Stelson
is the Founding Director of the NSF Engineering Research Center for Compact and Efficient Fluid Power.  He is College of Science and Engineering Distinguished Professor in the Department of Mechanical Engineering at the University of Minnesota where he has been since 1981.  He received his B.S. degree in mechanical engineering from Stanford University in 1974 and his S.M. and Sc.D. degrees in mechanical engineering from M.I.T. in 1977 and 1982.  Stelson’s fluid power research includes work on improving the efficiency of off-road vehicles and developing hydrostatic transmissions for wind power. Stelson has received the Rudolf Kalman Best Paper Award from ASME twice. He is a Fellow of the AAAS and ASME, and he has received the Koski Medal from ASME and the Brahmah Medal from the Institution of Mechanical Engineers (UK).