29327 - Mechanics of Machines T

Learning outcomes

To provide the tools to understand the composition of machines and the principles of operation, the kinematic and static analysis, the dynamics of the rigid and flexible bodies machines, with the related problems.

Course contents

1. Composition of machines
   • 1.1.Introduction
   • 1.2.Machines, mechanisms, members and classification
   • 1.3.Degrees of freedom and constraints in plane and in space
   • 1.4.Kinematic pairs
     • 1.4.1.Rotoidal
     • 1.4.2.Prismatic
     • 1.4.3.Cylindrical
     • 1.4.4.Helical
     • 1.4.5.Spherical
     • 1.4.6.Cylinder on cylinder
     • 1.4.7.Cylinder in groove
     • 1.4.8.Pair classification
   • 1.5.Kinematic chains. Planar and spatial mechanisms
   • 1.6.Degrees of freedom of a mechanism
     • 1.6.1.Definition
     • 1.6.2.Grubler and Kutzbach formulas
     • 1.6.3.Application examples
     • 1.6.4.Inessential dof
     • 1.6.5.Repeated constraints
     • 1.6.6.Mechanisms with 1 or more dof
2. Elements of rigid-body mechanics
   
   • 2.1.Internal and external forces
   • 2.2.Moments and transport theorem
   • 2.3.Resultant vector and moment of a system of forces
   • 2.4.Couples and generalized systems of forces
   • 2.5.Reduction of a system in plane and in space. Resultant force.
   • 2.6.Equilibrium of a mechanical system
   • 2.7.Geometric relationships in equilibrated force systems
     • 2.7.1.2 forces
     • 2.7.2.3 forces
     • 2.7.3.4 forces
     • 2.7.4.variants
3. Dissipative actions in machine components
   
   • 3.1.Contact types in kinematic pairs
   • 3.2.In/output members, motors/users
   • 3.3.Kinetic friction.
   • 3.4.Static friction. Friction cone.
   • 3.5.Coulomb model
   • 3.6.Causes of kinetic friction. Surface status. Lubrication.
   • 3.7.Friction coefficient values. Influence of temperature and speed.
   • 3.8.Rolling contact
     • 3.8.1.Static friction
     • 3.8.2.Hertz theory
     • 3.8.3.Causes of rolling friction
     • 3.8.4.Rolling friction parameter
     • 3.8.5.Rolling friction coefficient
   • 3.9.Wear
     • 3.9.1.Adhesive and abrasive wear
     • 3.9.2.Determination of the volume of removed material
     • 3.9.3.Reye hypothesis
     • 3.9.4.Wear for surface fatigue
   • 3.10. Energy equations
   • 3.11. Energy balance of a machine during direct motion. Periodic and absolute regime.
   • 3.12. Efficiency in periodic and absolute regime: definitions
   • 3.13. Instantaneous efficiency
   • 3.14. Inverse motion. Energy balance of a machine during inverse motion.
   • 3.15. Efficiency of inverse motion
     • 3.15.1.Definitions
     • 3.15.2.Relationship between direct and inverse motion efficiencies
     • 3.15.3.Possibility of inverse motion
   • 3.16. Efficiency of machines in series and in parallel
   • 3.17. Inclined plane
     • 3.17.1.Driving force: graphical and analytical solution
     • 3.17.2.Efficiency of direct and inverse motion
     • 3.17.3.Conditions for the inverse motion
     • 3.17.4.Verification of the relationship between direct and inverse motion efficiencies
4. Static analysis of kinematic pairs
   • 4.1.Rotoidal pair
     • 4.1.1.Ideal and real constraint reaction
     • 4.1.2.

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