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ACTUAL PROBLEMS OF AVIATION AND AEROSPACE SYSTEMS
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Theoretical mechanics in higher education

(from Arhimed to SC “Buran”)

Yuriy G.Martynenko

Institute of Mechanics of Lomonosov Moscow State University

Russia

Domestic industry is currently experiencing a vital shortage of scientific and technical professionals capable of solving emerging pivotal technical problems at the state-of-the-art level.  College graduates lack of expertise is primarily attributed to an overall decline of the physical and mathematical education that emerged in the last quarter of the 20th Century. It is indubitable that the sustainable development of any country is not simply defined by its natural resources but predominantly by the nation-wide educational level. An overall educational crisis is driven by convergence of objective reasons such as a world economic crisis, intellectual migration and unprestigious engineering job societal positioning and subjective reasons linked to economic globalization and competitive frenzy of industrialized countries to establish technological dominance via intentional leveraging the educational systems of potential competitors toward a diminished state. Furthermore, an existing inter-departmental competition within any high education institution leads to substantiation of curricula not favoring the physical-mathematical disciplines.

Nowadays phenomenon is that many college graduates with a somewhat narrow field of expertise are quite frequently left unoccupied since the new technologies are already leaving thousands of experts unemployed. As a vivid example, recent satellite navigation systems market introduction transformed previously in demand jobs in gyroscopic specialty into an unnecessary archaic. Only in-depth fundamental knowledge base remaining invariant within the frame of the modern informational explosion provides recent college graduates an adaptation means toward any practical activity deviation.

Core essence of the natural-sciences disciplines evolution is far from being trivial. It is a paramount task of today to prepare true experts of tomorrow ready for new technologies to come. Moreover, presently both mathematics and physics turned into complicated inter-linked conglomerates of separate sciences. Modern mathematics superabstractionism can easily lead to a lack of understanding between two professionals working in different fields of mathematics. At the same time a substantial side of ‘pure mathematics’ fundamentals start to disappear substituted by casuistic exercises in formal manipulation of abstract concepts lacking any solid meaningful ground. Even outstanding mathematicians are prone to mistakes when considering simple problems.

That is what has elevated theoretical mechanics to a special place in a physical and mathematical sciences cycle. An unprecedented role of the theoretical mechanics as a logical linkage between the mathematical abstractionism and real world physics was underlined by one of the outstanding scientists of the 20th Century A.Yu.Ishlinsky who contributed invaluably to the development of the gyroscopic and navigational systems for autonomous control of space vehicles. It was Ishlinsky’s strongest belief that it is impossible to meet a state demand in engineering and teaching professionals capable of driving a scientific and technological progress without a full-scale comprehensive physical and mathematical education. Consequently, A.Yu.Ishlinsky has valued tremendously his duties as a Chairman of the Theoretical Mechanics Scientific-Methodological Council at the USSR Ministry of the Higher and Special Education which was established in 1964. As a Chairman of the SMC, A.Yu.Ishlinsky has conceptualized (defined) its primary task as an improvement in teaching of theoretical mechanics remaining to be a fundamental discipline of the physical and mathematical cycle. Obviously, this work could not be simply accomplished via directives from above. Instead it should be based on collective (collaborative) experience and knowledge accumulated by various university faculties which need to be thoroughly studied, synergized and disseminated. Within the Council A.Yu.Ishlinky had managed to unite the leading experts in mechanics, brilliants scientists and outstanding teachers.

In theoretical mechanics SMC has been engaged in the following activities: development of educational programs and curricula, textbooks analysis and curricula studies, teaching methodology refinement, best practice sharing and exchange of experience between the departments of theoretical mechanics. It integration into educational process and necessity to modernize the fundamental components of the theoretical mechanics has been added to the list of the current SMC activities.

Excluding the theoretical mechanics, perceived as an independent natural sciences discipline, from the base fundamental educational cycle jeopardize the educational level of modern experts, deprive their intellectual foundation thus subsiding the future expert’s generation potential to inspire the new technological advances. Having few separate mechanics-related sections covered within the generic physics course does not compensate the need of full-scale advanced (comprehensive) courses delivered at the state-of-the-art level by professional educators.

To reiterate the importance of mechanics, it is crucial to emphasize that many major discoveries in the history of mankind have been made upon solving mechanical problems. For example, Kepler’s discovery of the elliptical orbital planetary motion has led to the revelation of the law of universal gravitation. Rutherford’s atomic structure discovery has been made while analyzing the charged particle motion within the atomic nuclei field. Optimum control theory considered to be a scientific breakthrough of the 20th Century has been heavily based on the principles of the analytical mechanics.

Theoretical mechanics principles and methodology as well as its computational algorithms have penetrated across-the-board into all areas of technology, biology, medicine and even non-technical disciplines. Numerous modern purely mathematical disciplines have been originated within the classical mechanics framework. Therefore, theoretical mechanics being a bridge between the fundamental disciplines (advanced mathematics and physics) and the engineering disciplines (strength of materials, material science, theory of machines and mechanisms and hydraulics) provides powerful means towards formation of the physical and mathematical modeling mentality of the students.

It is imperative to address the proper positioning of mechanics within the 20th Century science infrastructure. Presently it is counterfactual to consider mechanics as a simple branch of physics or mathematics (or ‘branch of analysis’ as it was proposed by renowned Lagrange at the end of the 18th Century in his famous ‘Analytical Mechanics’ publication).

Mechanics has currently emerged to become an independent science stirring modern scientific and technological progress. Mechanics as a science is not only famous for its historical achievements but for the breakthroughs and phenomenal, stunning results of modern days as well. It is impossible to successfully execute other natural sciences achievements without synergizing those with the developments in mechanics.

Unfortunately, it is a modern day misconception imposed by the mass media that mechanics is an outlived archaic science with no room for future discoveries. This is further misconceptualized by a high-ranking scientists and officials claiming that the experimental and research work in mechanics can be easily substituted by virtual numerical experimentation and thus unnecessary. Thus the proponents of this erroneous point of view believe that the modern specialized computer software packages made redundant whole sections of mechanics. In particular, it refers to the uselessness of the study of solid mechanics, as well as packages based on finite element method allow us to calculate the strength characteristics of any design. Not in any way denying the fantastic possibilities of modern computers, it is necessary to mention the terrible disasters that were the result of improper use of computing means. Verification of the results of any numerical calculation must be carried out by experts freely owning basic mechanical laws. Examples of the decision of the same mechanical problem by means of different packages of the licensed programs and reception thus opposite results are already known.

As example of rough blossoming of mechanics designing and creation problems robotic systems which are on crossing of different sciences – mechanics, electronics, computer science, cybernetics serve. They have caused to a life new, a knowledge boundary region – so-called «mechatronics » (from words of "mechanic" and "electronics").

Various types of mobile robots are already created and are at a perfection stage, beginning from one-wheeled devices to multilegged and biped walking machine. Even more amazing prospects are opened for development biomechatronical systems. Biomechatronics is the new science which purpose is studying of interaction of biological organisms with integrated mechatronic modules.

Mechanics is a key area of scientific and technological progress. Without the mechanics development it is impossible to solve the problems of improvement of the reliability of structures and facilities, to prevent man-made disasters, the causes which tend to be incompetent, not only the operating staff, but also developers.

Fundamental knowledge can enter the legitimate promotion of original scientific achievements, have a solid foundation for the struggle against pseudoscience, the activity which has recently increased significantly. On pages of newspapers and magazines, on the Internet and on TV there is an advertising of the doubtful medical devices curing of hundreds of illnesses at once, promises of power abundance at the expense of use torsion fields, energy of vacuum and a gravitational field.

The pseudo science far is not harmless, as carrying out of pseudoscientific researches absorbs considerable material resources. Only absence of corresponding fundamental formation at officials from a science it is possible to explain decision-making on carrying out of experiment obviously doomed to failure on the satellite "Jubilee" started in May, 2008. On this small satellite the tests of «mover without emission of jet mass», developed in one well-known scientific research institute, were conducted. The details of the flight results of the satellite "Jubilee" are absent, although in April 2009 a very "modest" message about "the ambiguity of the results of this experiment” is appeared.

In fact, the developed engine represents an inertia drive, traction force which "created" by the internal forces that arise when "the movement within the apparatus of liquid or solid working body in a definite path, shaped like a tornado»(?). In the framework of modern physics, which recognizes the existence of four fundamental force fields, no opportunities to speed up moving objects without any external forces or reactive thrust does not exist. From the basic theorem of theoretical mechanics of the motion of the center of mass of a mechanical system it follows that, for any movement of the working body within the satellite "Jubilee" its center of mass will move along a trajectory that can be predicted with a high accuracy from well-known and well-tested equations describing motion of bodies in near-Earth space under the action of external gravitational, electromagnetic and aerodynamic forces.

It triumphs of celestial mechanics, whose creation was initiated more than three centuries ago, have made a significant contribution to the formation of dogma of experimental studies - to recognize only such as scientific methodology, which ensures the reproducibility of experimental results, when and wherever they were received. It is from this dogma implies failure astrology, telepathy and other such "sciences".

The first triumph of celestial mechanics was the solution by Newton in the late XVII Century, two-body problem, which led to a scientific explanation of Kepler's laws. Mathematical analysis of the strong perturbations in Uranus allowed Urbain Le Verrier predicted the existence of Neptune, first seen by Galle in 1846. In 1930 the discovery of Pluto by Tombaugh has followed. Not so long ago, open on the outskirts of the solar system object under number 2003 UB313, tentatively called Zeno (Eris) can either supplement the list of planets, or its shortened. It will be clear only after final approval of the definition of planets in the solar system. According to the resolution of the International Astronomical Union, adopted in August 2006, the Solar System consists of the following eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune, and three dwarf planets: Ceres, Pluto and the object 2003 UB313.

Speaking about the problems of teaching theoretical mechanics, which is considered by some scientists as archaic part of science, it is appropriate to recall the words of Henri Poincare, uttered more than 100 years ago when a new quantum mechanics has appeared: "Teachers can not resist the temptation to tell his disciples that classical mechanics has outlived its time and is suitable only for the old fool Laplace. This creates the scornful relation to classical mechanics, without which it is impossible to understand the new mechanics".

Despite the seeming simplicity of the original provisions and the basic laws of classical mechanics, their assimilation requires a good knowledge of mathematics and a clear mechanical thinking. Systematic grounds mechanics requires the construction and use of complete and coherent system of primary concepts of mechanics. These concepts are space, time, inertia, interaction, measures which are distance, duration, weight and strength, needed to be clearly spelled out in teaching. There are many examples of misunderstandings and misinterpretations in the question about the source of classical mechanics, it is sufficient to refer to the occasional different interpretations of the inertial forces. Only scientific foundation of grounds of mechanics can resolve in many discussions is very controversial, to fully clear up the seemingly hopelessly knotty questions.

Of course, the development of modern science clarifies the limits of applicability of the theoretical and mechanical models. In this regard an important step was taken recently at the conclusion of the experiment to verify Einstein’s general theory of relativity (GTR). This experiment called Gravity Probe B and its preparation was begun at Stanford University in 1960.

The idea of experiment is simple enough and uses in conducting three things: a gyroscope (spinning ball), a telescope and a fixed star. According to classical mechanics in the absence of external moments rotating ball remains unchanged in the space direction of the axis of rotation. According to general relativity near a massive rotating body (the Earth) due to the curvature of space axis of the gyroscope starts a precession.

The angular velocity of the geodetic precession Ω is defined by formula of L.I.Schiff (1960).

The predictions of general relativity give the following quantities: the deflection axis of the gyroscope for the year due to the curvature of space (the first term in L.I.Schiff formula) 6,6 arc. sec. to the North, the deviation of the gyroscope axis due to Lense-Thirring effect (second term in this formula) 0,042 arc. sec. with the direction of rotation of the Earth.

Disturbing moments acting on the rotor of the most accurate to date of electrostatic gyroscope installed at the Earth’s surface, causing the drift of the axis of rotation of the rotor, which is many orders of magnitude greater than the angular velocity of the geodetic precession. Therefore, for the registration of this drift it was decided to use a cryogenic (refrigerated to a temperature of 2.6 К close to absolute zero) gyroscope placed on board the low-flying satellite. In addition, the satellite is set a telescope directed at the star in the constellation Pegasus.

Preparatory work for the described experiment took more than 40 years.  Requirements for cryogenic gyroscope were so high that it has raised questions about whether they are achievable in principle. In 1967 the French physicist Raymond Mathey was the first who solved the problem of the thermodynamic barrier for non-contact precision gyroscope, determined by the thermal motion of molecules and leads to its drift. It was shown by Mathey that for accurate registration of the main relativistic precession it is not sufficient the accuracy of an ideal gyroscope with temperature superconducting niobium. V.F.Zhuravlev shown that Mathey erred when improperly used to model the movement of warm crystal lattice theory of Dulong and Petit of thermal conductivity of the gyroscope, unworkable in the vicinity of absolute zero. Built with the help of Debye's theory, this model shows that the error does not fall as the square root of the absolute temperature (the result of Mathey), as well as the square of the temperature, so that when the temperature drops to 100 times the error is not reduced by 10 times, like Mathey, and 10000 times, which makes the thermodynamic barrier is irrelevant.

Gravity Probe B was launched from Vandenberg Air Force Base, California on 20 April 2004. Weight of satellite was 3175 kg, it was placed in a circular low Earth polar orbit at a height of 640 km. On board of the satellite there were 4 cryogenic gyroscopes which casual drift was up to level of 10-11 degrees/hour. Non-spherical of quartz rotors of the gyroscopes was 10 nm (which corresponds to a film thickness of 40 atomic layers!). In a satellite compartment in which there were gyroscopes, the ultrahigh vacuum has been created, and it was s shielded from external magnetic fields of superconducting magnetic shield. Precision of the telescope established on board of satellite to three orders of magnitude better than precision of the best astronomical devices. It was one of the most sophisticated satellites ever launched from Earth's surface. After spin up of gyroscopes in August 2004 there has been begun data collection from the 9000 sensors installed on board of the satellite. The recording time of data was 353 days, which brought together a total of about a terabyte of information. The satellite worked in space about 17 months and completed its mission on Oct. 3, 2005. The cost of the experiment was over 700 million dollars. Full data processing has not yet been finalized, but first made public the results of the probe, it follows that the Gravity Probe B with an accuracy of one percent (!) confirmed the fidelity of Einstein's allegations that items such as the Earth distorts the structure of space-time.

Solution of problems of scientific and technical progress requires the use of the latest achievements of the various areas of science, among which one of the main places occupies the mechanics. Only well-educated professionals who have deep fundamental knowledge can introduce these achievements.

Serious science education can not be a luxury but a reduction in physical and mathematical components destroy education and deprive our country of opportunity to be among the leaders of scientific and technological progress. That is why it seems useful to create and support specialized training programs to address the innovation challenges of scientific and technical progress.



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