07-10-2016, 09:07 AM
1458119941-MT2.doc (Size: 664 KB / Downloads: 2)
Abstract
This paper outlines the emergence of mechatronic engineering as a distinct professional activity and area of study. Current and future trends in mechatronic engineering and the educational needs of its practitioners are discussed.
Many modern products use embedded computers (computer-on-a-chip) to provide hitherto unattained functionalities exclusively through mechanical means. One may also exploit the ability of a computer to be programmed at will to add new functionalities. For instance, we can create „smart‟ products by programming the computer on the basis of fuzzy logic, or by making the computer behave like an artificial neural net (ANN). Thus computer technology offers an opportunity for endless product innovation. Mechatronic egineering is the emerging discipline that supports the development of this class of technological processes and products.
Although USA and Europe had contributed significantly to the development of M, E, and C technologies described above, it was Japan that had first recognized the strategic importance of mechatronics as a distinct discipline. Indeed, much of Japan‟s economic success since the 1970s seems to be linked to its mastery of mechatronic engineering . However, soon, the concept of mechatronic engineering spread to many other parts of the world. For instance, in Denmark, a full PhD project was devoted to the development of a theoretical approach to mechatronic design . By the 1990s, several mechatronic courses/programs within and outside departments mechanical engineering programs started appearing worldwide: e.g., Australia , Hong Kong, Mainland China , and UK . In Singapore, mechatronics is even introduced at the secondary school level . In Russia, mechatronics courses are introduced within aeronautic engineering programs . Chronologically, the first full-length mechatronic programs to be offered within the Asia-Pacific region was that launched (under the leadership of the first author) in 1989 at City University of Hong Kong (then City Polytechnic of Hong Kong). More recently, mechatronic engineering undergraduate programs have been launched at two engineering colleges in Andhra Pradesh, India. These represent the first ever mechatronic education ventures in India.
The proliferation of mechatronic engineering programs in universities worldwide, in turn, is leading to a deeper understanding of the specific natureof mechatronic engineering, how it could be taught more effectively , and the software tools needed for mechatronic design and its teaching
4 What is Mechatronic Engineering? What it is not?
Since mechatronic engineering is an emerging discipline, it is not surprising that its definition is still under development. Among the more popular definitions is the one composed by the Industrial Research and Development Advisory Committee of the
European Community: Mechatronics is “a synergistic combination of precision mechanical engineering, electronic [read computer] control and systems thinking in the design of products and manufacturing processes.”
While the above definition seems to be acceptable in the short term, several simplistic views or, even, misconceptions continue to prevail. Two examples are:
Mechatronics is “the application of microelectronics in mechanical engineering”.
i. There must always be a design goal that is mechanical in nature. Hence, designing a voltmeter is not a mechatronic activity although the casing of the voltmeter is mechanical in nature. The mechatronic activity needed is dictated by this „mechanical‟ goal. This goal is often expressed as a set of performance variables that need to be controlled (constrained within limits or optimized). Hence control engineering (especially, motion control) is central to mechatronic engineering.
ii. The design solution is invariably a system. A system is a set of interacting elements satisfying a specified goal. In the case of a mechatronic solution, the elements can be of mechanical, electronic or software types. The interactions can be of analog or digital .
iii. Mechatronics is NOT about finding ANY solution to the given problem. Its aim is to produce a competitive solution. Typically, there exist a range of solutions to a given design problem. Often, a purely mechanical solution is feasible. If this is the best‟ solution, it does not fall within the domain of mechatronics. Mechatronic design invariably involves tradeoffs between the advantages of alternative mechanical, electronic, and software solutions at the sub-unit level. Experience shows that an M-solution is usually inferior to a competing E-solution which; in turn, is inferior to a C-solution . Hence, the hallmark of mechatronic engineering is the conscious effort to progressively substitute M-solutions by E-solutions and, in turn, E-solutions by C-solutions.
4. What Professional Roles Do Mechatronic Engineers Fulfill and What Knowledge and Skills Do they Need?
Technological process or product design in a modern context is usually a group activity that involves the communications among electrical, electronic, materials, mechanical, manufacturing, and other types of scientists and engineers. Usually, the team members are specialists in their respective disciplines/professions. Conventionally, such teams have been coordinated by one of the specialists with
. Mechtronic Education
Section 3 has already drawn attention to a range of educational initiatives focusing on mechatronics. Following these developments, several pedagogic principles of specific relevance to mechatronic education have emerged.
It was noted in that mechatronic design
“is a complex and open ended activity requiring refinement of creativity and experience through application;
is often a group activity in industrial practice; is a combination of art and science;
requires a broad overview of market needs and business goals, and manufacturing technology.”
These considerations had led program of City University of
the designers of the BEng Mechatronic Engineering Hong Kong to adopt the following curricular strategy
“While the Japanese view of the mechatronic engineer as a mechanical engineer whose education is broadened to include microprocessors, electronics, actuators and control is broadly valid, as far as possible, avoid biasing the students towards a specific discipline i.e., emphasize and interdisciplinary approach.
Develop the mechanical and electronic design aspects systematically while providing a broad understanding of computers to enable their effective utilization in design.
recognize that control engineering (especially motion control) is a core activity.
Develop a broad understanding of the interactions [among] design, manufacturing and design management.
Take advantage of computer aided design and analysis (CAE) software in order to enable students to undertake more substantial design tasks.
Develop the skills in technical communication required by all engineers.”
An outline of the curricular structure following the above principles is illustrated in is at the very center of the curriculum.
Milne et al note that the core disciplines of mechatronics (mechanics, electronics, and computing) are usually taught separately in different engineering departments in a
“bottom-up” manner from fundamental principles and concepts. In contrast, they suggest that mechatronics “requires a systems-thinking attitude where consideration is given to the overall objective rather than individual components, which is evidently
“top-down”. Therefore, special attention has to be paid to mechatronics education .
Team-based projects can be used to achieve experience-based learning of group goals, individual accountability, equal opportunities for success, team competition, task specialization, and adaptation to individual needs .
It is useful to make team-based projects industrially relevant. Provided that sufficient resources are available, robotics can be used a potent arena for mechatronic projects undertaken even by undergraduate students. Projects aiming to develop robots capable of cleaning glass window panes in high rise buildings, filling automobile petrol tanks, playing table-soccer, cleaning floors in hospitals, and vacuum cleaning in homes are amongst the project undertaken by teams consisting 3 to 5 undergraduate mechatronic students at the City University of Hong Kong. Likewise, groups working under the supervision of the first author have worked on a robotic home kitchen system, a 4-axis
8
CNC turning/milling center, and a smart shopping cart using radio frequency identification chips to replace bar code reading technologies currently in use in super markets worldwide. Note that, contrary to popular opinion, the scope of mechatronics extends well beyond robotics.
6. Future Trends in Mechatronic Engineering
By definition, automation is the replacement of human labor. And technology is (just) a bag of tools that come in the form of hardware and/or software. A tool is something that assists in performing existing tasks better or enables new tasks to be performed. In other words, it somehow replaces human labor, i.e., automates the task. Thus progress in technology (through mechatronics, or otherwise) is synonymous to automation.
Human activity can be broadly divided into two categories: individual or collective (social). Individual activities may be purely mental or combined with physical activity. Irrespective of whether it is reflexive or reflective , any human physical act requires effort at five levels:
(i) Setting the goal (a purely mental activity).
(ii) Sensing the environment through the five sensory organs eyes, ears, skin, tongue, and nose.
(iii) Communicating the sensory signals to the central neural processor called the brain.
(iv) Fusing the signals to recognize patterns of interest and output the command signals to human limbs.
(v) Performing the physical task using limbs (actuators).
A remarkable human ability is to learn from the results obtained from past acts so as to perform better when executing similar tasks in the future. This learning ability provides human beings with the ability to act as autonomous units. A further ability lies in communicating with other human beings so as to undertake collective tasks.
The above description of human abilities provides a basis for understanding and trends in mechatronics.
Sensing and sensor fusion will be the next capability to be acquired by mechatronic systems. Already, many mechatronic units possess rudimentary sensing abilities. For instance, modern air conditioning units are able to sense air temperature and humidity through separate sensors and fuse the signals through fuzzy logic reasoning. Likewise, sensors in the form of transducers have long been used to enable feedback control in machines. However, there is still a long way to go. Sensors produce copious amounts of data that need to be digested to discover patterns of interest before control can be effected through the „actuators‟. Advances in high-speed microcomputers and signal processing algorithms (such as those based on wavelet theory) have now opened the door for the exploitation of sensors exploiting a wide range of physical, chemical and, even, biological phenomena. While actuators are limited in variety, the variety of possible sensors is almost unlimited. For instance cutting forces in CNC machining and its consequences (e.g., tool fracture) can today be monitored and controlled using commercially available devices capable of sensing
9
machining noise, machine vibrations, acoustic emission, drive motor current , etc. Future mechatronic engineers will have to possess deeper understanding of natural sciences so as to cope with the growing variety of sensors. And they will have to learn to fuse these sensors using such emerging techniques as fuzzy logic reasoning and artificial neural nets .
Machine learning: Intelligence means adapting to the environment and improving performance over time . Within the domain of mechatronic engineering, “there has been considerable interest in learning through the use of ANN and fuzzy logic for applications in control and robotics, autonomous guided vehicles (AGV), etc., that require mainly reflective intelligence when performed by human operators and tasks, such as machine diagnostics, requiring combinations of reflexive intelligence and low level reflective intelligence [39].” This interest will continue well into the future.
Autonomization refers to the development of the ability to survive and perform robustly while the external environment changes. With progress in sensor and learning technologies, tomorrow‟s mechatronic devices can be expected to become progressively more autonomous. They will be able to reset their local goals autonomously under changing external environments so as to meet the broad system-level goals set by human beings.
Modularization will be a consequence of autonomization. Mechatronic sub-units will come in modular form, i.e., with all the abilities required for local goal setting, control, and learning encapsulated within the sub-unit. Thus, in time, every mechatronic sub-unit will be self-contained and intelligent. To the mechatronic engineer, they will appear as black boxes. All (s)he has to do is to choose the right combination of sub-units and build the desired system
Miniaturization refers to the trend towards mechatronic units of significantly smaller size. Progress in precision engineering, newer materials (composites, diamond coatings, etc.), and nano-technologies will contribute to this development
Links to the Internet: The Internet will become ubiquitous within the mechatronic world. Every autonomous mechatronic unit will be connected via broadband and satellite networks to the rest of the world. Each mechatronic device will be able to access the information and knowledge base available on the Internet so as to optimize its own performance. At the same time, it will be able to communicate its operational status to remote monitors. For instance, one would be able to query from one‟s office the refrigerator at home about its contents and receive a fairly accurate answer. Likewise, one can query a pillbox how many pills are remaining!
CONCLUSION
Future mechatronic engineers will have to learn to cope with the immense technological changes described above. Let us hope that educators of mechatronic engineers will keep up.