73112 - Mechanics and Dynamics of Machines (2nd cycle)

Course Unit Page

SDGs

This teaching activity contributes to the achievement of the Sustainable Development Goals of the UN 2030 Agenda.

Quality education Industry, innovation and infrastructure

Academic Year 2021/2022

Learning outcomes

The student acquires concepts and advanced methods for the functional design of the machines and is able to deal with issues concerning the modelling of mechanical systems, with reference to multibody systems and mechanical vibration.

Course contents

1. Kinematics of linkages. Planar linkages. The Four-Bar linkage. Analysis versus synthesis. Tasks of Kinematic Synthesis. Graphical synthesis. Analytical synthesis. Motion generation. Path generation. Function generation.

2. Cam design. Introduction. Cam and follower types. Pressure angle. Graphical cam profile synthesis. Analytical cam profile synthesis. Prevention of profile undercutting.

3. Gears. Conjugated profiles. Spur involute gears. Geometry of involute gears. Generation of involute curves by tools. Tooth element proportions. Rack-Cutter. Undercutting. Wildhaber's concept. Modified involute Gears. Involute Helical Gears with parallel axes.

4. Dynamics of Machines and Fundamental of mechanical vibrations.

5. Single Degree of Freedom Systems.

6. Two Degrees of Freedom Systems.

7. N Degrees of Freedom Systems.

8. Continuous Systems.

9. Vibration measurements and modal analysis.

10. Elastodynamic modelling. Lumped parameter modelling of continuous systems and mechanisms.

Readings/Bibliography

1. Funaioli E., Maggiore A., Meneghetti U., “Lezioni di Meccanica applicata alle macchine, (I, II e III parte)”, ed. Pàtron, Bologna.

2. Erdman A.G., Sandor G.N., Kota S., “Mechanism Design: Analysis and Synthesis”, Prentice Hall, 4th edition. ISBN: 0130408727.

3. Norton R.L., “Cam Design and Manufacturing Handbook”, Industrial Press, ISBN: 0831131225.

4. Litvin F.L., Fuentes A., “Gear Geometry and Applied Theory”, Cambridge University Press, 2nd edition. ISBN: 0521815177.

5. Rao S.S., “Mechanical vibrations”, Third edition, Addison Wesley Pub. Company, 1995.

6. Inman D.J., “Engineering Vibration”, Prentice Hall, 1994.

7. Slides and notes from the lessons.

Teaching methods

The lectures will focus on theoretical aspects of the course items. The lectures will be supplemented with practical exercises.

Class attendance, although not mandatory, plays a fundamental role in the learning and evaluation process.

Assessment methods

The final examination is oral and consists of three questions that aim to ensure the acquisition of knowledge expected by the course program and to assess the achievement of learning objectives:

  • knowledge of advanced methods for the functional design of the machines;
  •  ability to deal with issues concerning the modelling of mechanical systems, with reference to multibody systems and mechanical vibration.

The ability of the student to articulate and correctly explain the answers to the questions, has a fundamental weight in the attribution of the final marks.

To be admitted to the examination, students must deliver to the examining commission some solved exercises, as specified in https://virtuale.unibo.it.

In accordance with the Art. 16 of the University Didactic Regulations, if a positive grade does not meet the expectations of a student, the latter may ask its cancellation and the repetition of the examination. The instructors of the course comply with the following rules:

  • a student may request the cancellation of a positive grade only within the date of the examination;
  • a cancelled positive grade can in no way be recovered;
  • a student may request the cancellation of a positive grade at most once.

Teaching tools

Blackboard, PC.

On the E-learning Platform (https://virtuale.unibo.it), students may find: slides of the course lectures; exercises and application examples.

Office hours

See the website of Alessandro Rivola