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# The theory of mechanisms and machines

## The Geometry Of Motion

The theory of mechanisms and machines is an applied science that is used to understand the relationship between the geometry and motions of the parts of a machine are mechanism and the forces which produce these motions. The subject and therefore this book naturally divides itself into three parts. Business is the groundwork of chapters 6 to 11 where we study methods of design of mechanism and machine components. Finally, in chapters 12 to 17, we take up the study of kinetics that I am wearing forces in machines and the resulting dynamic phenomena which must be considered in their design.

As shown in figure 1.1 the design of modern machines is often very complex. In the design of new ones, for example, the automotive engineer must deal with many interrelated questions.

What is the relationship between the motion of the Piston and the motion of the crankshaft? Hot wheel with the sliding velocities and the loads at the lubricated surface and hot look like ads are available for the purpose? How much heat will be generated and how will the engine be cooled? What are the synchronization and control requirements and how will they be made? What will be the cost of the consumer both for the initial purchase and for continued operation and maintenance? What materials and manufacturing methods will be used? What will be the fuel economy no as an exhaust emission will they meet legal requirements?

All these and many other important questions must be answered before the design can be completed. Obviously, not all can be addressed in a book of this size. Just as good people with diverse skull masks are brought together to produce an adequate design, so too many branches of science must be brought to bear. This book brings together material that falls into the science of machines as it relates to the design of mechanisms and machines.

## Analysis and synthesis

There are two completely different aspects of the study of mechanical system design analysis. The concept embodied in the world design might be more properly term synthesis is the process of contriving a scheme or a method of accomplishing a given purpose. design is the process of describing the size, shape of the material, confirming the composition and arrangements of the parts so that the resulting machine will perform the prescribed task.

Although there are many faces in the design process which can be approved in a well-ordered scientific manner the overall process is by its very nature as much of a heart as a science. It calls for imagination, intuition, creativity, judgment, and experience. The role of science in the design process is nearly to provide tools to be used by the designer as they practice their art.

It is in the process of evaluating the various interacting alternatives that designers find lead to a large collection of mathematical and scientific tools. These tools, when properly applied, can provide more accurate and more reliable information for use in jazz method design that can achieve intuition or estimation. 10 days can be of tremendous help in deciding between alternatives. However scientific tools cannot make decisions for designers. They have every right to exert their imagination and creativity is given to the extent of overruling the mathematical predictions.

Wali the largest collection of scientific methods at the designer’s disposal falls into the category called analysis. These are the techniques who is allowed the designer to critically examine an already existing or proposed design in order to charge the suitability of the task. The analysis in itself and eat a creative scientist science but not one of evolution and rating of these things already exist.

You should always be there in mind that most of our effort may be spent on analysis the real goal is synthesis the design of a machine or system analysis is simply a tool it is, however, a vital tool and will inevitably be used as one step in the design process.

## The science of machines

The branch of scientific analysis with deals with motions time and forces is called machine and is made up of two parts is statics and dynamics. Statics deals with the analysis of stationary systems as an example those in which time is not a factor and dynamic deal with systems that change with time.

As shown in figure 1.2 dynamic is called made up to measure discipline was recognized as separate entities by a user in 1775 Plus.

The investigation of the motion of a rigid body may be conveniently separated into two parts one geometrical The other machine in the first part the transference of the body from a given position or other person is in this created without respect of the cause of the motion and must be represented the analytical formulas which will be defined the position is point of the body this investigation will therefore be reflective also lead to geometry.