Leng Junfa Jing Shuangxi Henan University of Technology Jiaozuo Henan 454000 Abstract: Aiming at the problems of outdated teaching content, unreasonable structure, rigid and boring teaching methods of the mechanical fault diagnosis course, some measures for the teaching reform of the course were proposed, and students-based and teacher-led methods were established based on fault diagnosis theory , Technical methods and engineering application research integrated teaching model to improve teaching quality. The mechanical fault diagnosis course is a professional course, which is closely connected with the courses of mechanical engineering test technology and mechanical vibration. It is directly related to production practice, scientific research and daily life. In recent years, with the breakthrough research of sensor detection technology, electronic computer technology, signal processing technology, etc., the mechanical fault diagnosis course has changed greatly from theory, method to application field. It is required that the teaching of this course should have a wide range of knowledge and practicality, combined with new theories, new methods and new fields of use, so that students can understand the cutting-edge dynamics. The traditional educational content, methods, and methods of this course have many merits that are worthy of recognition, but there are also obvious shortcomings. For example, the teaching content is lagging and unreasonable, the teaching methods are dull, and there is a lack of cultivation of students' hands-on ability and active thinking. The author believes that the teaching reform of this course should focus on improving the teaching quality, reforming the teaching content and teaching methods, and using case teaching, discussion teaching and other methods of research teaching as means to improve the teaching quality. 1 Problems in course teaching 1.1 Problems in the course content 2 Curriculum teaching reform 2.1 Teaching content reform Figure 1 "Rotor imbalance" comprehensive teaching model It can be seen from the comprehensive teaching model that vibration mechanism analysis is the foundation, sensor selection and calibration is the guarantee of signal acquisition, signal processing is technology, and monitoring and diagnostic software is the platform. In addition, we must strengthen the comparison between the theoretical conclusion (through simulation analysis) and the actual analysis results to find out the differences and the causes. Therefore, only by learning all the contents of this model (which can be extended to the learning of other mechanical failure models) can we truly achieve the organic concatenation and integration of various parts of knowledge to form a complete knowledge system. At the same time, it can better cultivate students' ability to analyze and solve problems, as well as their engineering awareness and innovation ability, so as to achieve better teaching results. 3 Conclusion The teaching of professional courses must establish an integrated teaching model with students as the mainstay and teachers as the mainstay, based on professional theory, technical method research and applied research. It can also draw on the creative talent training ideas of "doing middle school" and "experiential learning" abroad, according to "How to solve a practical engineering diagnosis case" to carry out mechanical failure diagnosis course teaching planning and organize teaching activities, and explore and research the characteristics of this course The adapted teaching methods and methods form the teaching content and methods with the professional characteristics of the mechanical fault diagnosis subject. references [1] An Qi. Teaching model of systematic cultivation of innovative ability [J]. Higher Engineering Education Research, 2004, 1: 77 ～ 79 Red Wine Canvas Tote Bags are covered with printed canvas to the surface with a layer of transparent PVC film, making the canvas fabric which is strong and wear-resistant even stronger. And fabric is easy to do, as long as the dirty wipe with a wet cloth can be. Canvas Tote Bags,Wine Freezer Tote Bags,Wine Canvas Tote Bags,Red Wine Canvas Tote Bags Wenzhou Shandao Electronic Commerce Co., Ltd. , https://www.reusablebaglife.com
Keywords: machinery fault diagnosis; teaching reform; case teaching method
Mechanical fault diagnosis belongs to professional curriculum education, and its theoretical, technical and practical applications are closely combined. The teaching content and methods must be adapted to the latest research results of its theoretical, technical methods and applications. The teaching structure of this course is not reasonable, and the teaching content remains unchanged. It can't keep up with the latest development of fault diagnosis technology. Without the breath of rapid development of science and technology, it is difficult to stimulate students' interest in learning.
The specific performance is in the following aspects:
(1) Some courses are not opened. Even if they are opened, due to the limited teachers and school conditions, the teaching time is only up to the point, and they cannot go deeper. This will inevitably cause students to lack theoretical knowledge or a weak foundation. For example, there are no courses on mechanical vibration, rotor dynamics, or signal processing technology, but a course on mechanical fault diagnosis, so that some vibration mechanism problems of mechanical faults cannot be solved, and only a preliminary understanding can be taken literally. Obviously this is not acceptable. of. Therefore, the establishment of professional courses must take into account the specific key knowledge points involved in the course, which should be taught before the class.
(2) The courses arranged are not reasonable, for example, in the field of mechanical fault diagnosis, related courses such as mechanical vibration, rotor dynamics and signal processing technology should be set up first. Even if they are offered in the same semester, these courses Courses are offered first, followed by mechanical fault diagnosis courses.
(3) The teaching content of the course is outdated. The content of teaching is basically the content of the 1990s, and it rarely involves modern fault diagnosis theory and development trends at home and abroad.
(4) The first courses involved in the courses are often independent of each other and are not linked together. The lack of cohesion and coordination between the courses, often after learning the next course and forget to attend the course.
1.2 Problems in course teaching methods
Like most other professional courses, traditional mechanical fault diagnosis courses have many disadvantages in teaching methods: dull, boring, time-consuming, laborious, and inefficient. The specific performance is in the following two aspects:
(1) Traditional "board writing" teaching is inefficient, poorly effective, wastes time, lacks classroom information, and is not conducive to the health of teachers and students.
(2) Teaching is a teaching mode centered on teachers, classrooms, and books. There are widespread phenomena such as "filling the whole room", "copying the subject and proclaiming the subject", and "learning and forgetting", which suffocates the students' positive thinking and innovative ability.
In terms of course content reform, we must change the current situation of the content of "cumbersome, difficult, partial, old" and partial book knowledge, strengthen the connection of course content with modern engineering applications and the latest research fields, pay attention to students' learning interests and experience, and refine After selecting students to participate in the work must have the professional knowledge and skills.
On the one hand, it is necessary to delete and simplify, and constantly update the course content. Delete content that deviates from the student's cognitive level and violates the student's cognitive law, delete old and backward content, and delete duplicate content, so that the content of the course is refined and new, reflecting the needs of the development of fault diagnosis technology and equipment maintenance technology. On the other hand, we must actively develop curriculum resources and continuously expand the new content involved in the curriculum.
According to the characteristics of the teaching content of this course, the following aspects are comprehensively optimized and reformed.
(1) During the course teaching, add some latest research dynamics about the course, including failure mechanism research, latest failure signal processing technology research, such as wavelet analysis, neural network, expert system, genetic algorithm, empirical mode decomposition, etc., fault diagnosis Research trends of instruments and systems (such as sensors, simple vibration meters, sound level meters, thermometers, pulse meters, amplifiers, samplers, etc.). In addition, the practical engineering application of fault diagnosis technology in the fault diagnosis of mechanical equipment in the fields of petroleum, chemical industry, transportation, aerospace, power generation, and mining is also added.
(2) Optimize the knowledge structure. All the knowledge points involved in the mechanical fault diagnosis course: mathematics (higher mathematics, linear algebra, probability theory, mathematical statistics, etc.), mechanics (theoretical mechanics, material mechanics, mechanical vibration, rotor dynamics, elastic mechanics, etc.), friction Learning, signal processing technology, sensor detection technology, computer technology, software programming (Matlab programming, LabVIEW programming, or VC programming, etc.), etc., according to the importance of the course, the order of the course, modular teaching. Of course, due to the limited duration of mechanical fault diagnosis courses, most of the courses that have been learned can only give a little hint to help students sort out the content they have learned and teach them as a whole.
2.2 Teaching method reform
The transformation of teaching methods should begin with the transformation of teachers ’educational ideas, first of all to establish teachers’ sense of responsibility and pride in education, secondly to establish an independent and active learning method for students, and finally to actively carry out extracurricular practical training. The combination of classroom teaching and extracurricular practice training is a form of teaching interaction.
For this course, specifically, we propose the following reform measures to improve the quality of teaching:
2.2.1 Adapt to the changes of the times and adopt multimedia and network modernization teaching
The advantages of using multimedia teaching are: to mobilize students' vision, hearing and thinking, so that students can complete their learning tasks in freshness and curiosity; multimedia teaching "new, environmentally friendly, efficient, large amount of information, resource sharing and network teaching" and other advantages In the classroom teaching, new theories, new methods and the latest research results, as well as a large number of engineering application cases can be passed to students through multimedia to stimulate students' interest in learning. To this end, we can make full use of our school's good modern educational technology and campus Internet, establish a multimedia network modern teaching platform, form an interactive teaching space inside and outside the classroom, and improve students' independent learning ability.
2.2.2 Adopt heuristic teaching and change passive learning into active learning
The teaching process of the mechanical fault diagnosis course is to train students to integrate the knowledge learned in the past and apply it to the mechanical fault diagnosis, which is a gradual process. In actual teaching, the relationship between "teaching" and "learning" should be handled well, and interaction with students should be strengthened so that students' thinking can keep up with the rhythm of teaching content. Inspire, guide students to study, think about problems and ask questions at any time, give students time to think about problems, mobilize students' subjective initiative in learning, and change passive reception into active learning. For example, when talking about gearbox fault diagnosis, ask: "When a pair of gears mesh with each other, the meshing stiffness is constant or changes; if it changes, what rule does it change?" The students' motivation to learn is mobilized. Teachers should encourage students to answer, and teachers should add what students did not say, so that they will have a good lecture effect.
2.2.3 Strengthen comprehensive teaching and cultivate students' comprehensive analysis ability
The contents of mechanical fault diagnosis courses are many and complicated, and the various parts are strongly interconnected and difficult to learn. Therefore, comprehensive teaching needs to be conducted on the basis of thoroughly understanding the comprehensive content. Comprehensive teaching can deepen students' understanding and understanding of what they have learned, so that the teaching structure is rigorous, the connection is strengthened, the thinking is clear, and the focus is prominent. From the perspective of the overall content of the course, apart from the introduction, each chapter is basically divided into three aspects: basic knowledge, basic theory, and basic technology. The three aspects are unified with each other, thereby strengthening the overall and systematic course. , To enhance the logic and organization of knowledge, eliminate the sense of chaos, and facilitate students' understanding and mastery. For example, for the study of "rotor unbalance", the comprehensive teaching model shown in Figure 1:
2.2.4 Teaching method of engineering application case
The core of professional curriculum education is to cultivate students 'independent innovation ability, and the formation of innovation ability is gradually formed in the process of analyzing and solving problems. The implementation of engineering application case teaching method is an effective method to cultivate students' innovative ability. Engineering application cases mainly refer to application research cases in the field of mechanical fault diagnosis. Through case analysis and discussion, the content can be closely integrated with engineering practice to stimulate students' enthusiasm for learning professional courses. For example, when it comes to gear box fault diagnosis, according to A large number of engineering application examples, according to the teaching model similar to Figure 1, very vividly introduced the vibration mechanism and fault characteristics of the gear box, fault signal acquisition and analysis methods, LabVIEW programming of monitoring and fault diagnosis software, etc., received a comparison Ideal teaching effect.
[2] Li Caiyun. A preliminary study on the teaching reform of the basic course of mechanical design [J]. Education and Vocational, 2008, 11: 108 ～ 109
[3] Xu Min, Huang Zhaoyi. Equipment fault diagnosis manual [M]. Shaanxi: Xi’an Jiaotong University Press, 1998
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An Analysis of the Teaching Reform of Mechanical Fault Diagnosis Course