


Politecnico di Torino  
Academic Year 2012/13  
03LMAJM, 03LMALI Applied mechanics 

1st degree and Bachelorlevel of the Bologna process in Mechanical Engineering  Torino 1st degree and Bachelorlevel of the Bologna process in Automotive Engineering  Torino 





Subject fundamentals
The course addresses the topics of mechanics that are a necessary part of the basic education of a mechanical engineer. Starting from the knowledge acquired by the student in the Physics courses, the objective of the course of Applied Mechanics is to provide the students with the necessary knowledge to properly address and solve engineering problems relevant to the mechanics of rigid bodies. The syllabus of the course will include:
 Description of the mechanics of rigid bodies and of the forces acting upon them.  Presentation of the main characteristics of mechanical drives and of their individual components, such as Hooke's joints, belt drives, gears and gear trains, power screws, clutches, brakes, bearings.  Outline of the basics of mechanical systems dynamics with particular emphasis to the mechanical vibrations. The course of Applied Mechanics links the description of the physics underlying the behaviour of mechanical drives and their components to the methods instrumental in solving engineering problems such to enable the students at the end of the course to properly address problems relevant to the mechanical systems and to the transmission of the mechanical power from a prime mover to an operating machine. 
Expected learning outcomes
The objective of the course is to develop the ability of the student to identify the problems relevant to rigid bodies mechanics, mechanical drives and mechanics of vibrations, to address them with a scientifically correct approach and to solve them with sound engineering methods in order to perform an effective functional design of mechanical systems.

Prerequisites / Assumed knowledge
Prerequisites for attending the course is a basic knowledge of calculus and physics.

Contents
Lecture topics:
Kinematics: particle kinematics, vectorial analysis, rectangular and local coordinates, Time derivative of unit vector. Polar coordinates. Rigid Body, connection of rigid bodies, translatory motion and rotation about a fixed axis, fundamental law of kinematics, Rivals Theorem. Instantaneous center of zero velocity. Piston rodcrank. Relative motions, Coriolis acceleration. Dynamics: operations on forces and moments, types of forces, constraint forces. Cardinal equations of dynamics, free body diagrams, examples. Work and energy, power and efficiency. Energy conservation law. Impulse, momentum and angular momentum. Conservation of momentum and angular momentum. Collision between bodies. Rotor dynamics: Central reference system, Static and dynamic balancing, flexural critical speed. Friction: static and dynamic friction, start of a vehicle, dry journal bearing, rolling friction. Brakes and Clutches: types of brake. Hypothesis of wear. Pad brakes: pivoted and not pivoted pad. Drum brakes: pivoted and not pivoted drum. Band brake and disc brake. Clutches: plane discs, conic discs. Examples of realizations. Transmission of the motion: Rigid and elastic couplings, mobile couplings, universal joints, Cardan joint. Homocinetic joints. Spur gears, involute profile, transmission ratio, geometrical dimensions, minimum number of teeth, Pinion and Rack, gear force analysis, manufacturing process. Helical gears, geometry and forces analysis. Bevel gears, geometry and forces analysis. Worm gear set. Gear trains: ordinary and epicyclical gear trains, automotive differential gear train. Flexible elements: belts, ropes, chains, stiffness of flexible, block and tackle. Power screws. Transient motion in mechanical systems: motor torque characteristics, direct coupling motoruser, coupling by means of clutch. Periodic steady machines, flywheel. Vibrations: 1 d.of. systems, series and parallel of springs, torsional oscillations. Damped free vibrations, logarithmic decrement, forced vibrations, accelerometer and seismograph. Lubrication: rolling and lubricated bearings, viscosity, one dimensional Reynolds equation, velocities profiles, types of bearings, hydrodynamic and hydrostatic pad. 
Delivery modes
Tutorials:
Are proposed exercises relatively on the topics, with the assistance of teaching staff and the solutions will be developed in classroom. Solutions will be also shown on the web page of the course. Laboratory: Experimental measures of efficiency of speed reducers and belt transmissions. Each team of students will prepare a final report of the results to deliver at the teachers before the exam. 
Texts, readings, handouts and other learning resources
Reference book:
C. Ferraresi, T. Raparelli, Meccanica Applicata, Terza edizione, Clut, Torino (italian version). The translation in english of the main parts of the text is available on the web page of the course. Other books: J.L. Meriam, L.G. Kraige, Engineering Mechanics, John Wiley and Sons. R. Juvinall, K.M. Marshek, Fundamentals of Machine Component Design, John Wiley and Sons. 
Assessment and grading criteria
The exam will be only in the written form.
Normally will be assigned three problems inherent the total program (lectures and training). The time of the examination is normally 2,5 hours. 
