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Trends in the modern machine-building industry

The scientific and technological progress will continue in engineering along two main headlines. Firstly, it is automation, including the creation of “unmanned” industries. Secondly, raising the reliability and extending the service life of machines.

This certainly requires new technology. The machine modules on a large scale are well suited for “unmanned” industries. Intense work is being carried out on new robots. What we need is not merely manipulators which can take up a work piece and pass it on, but robots which can identify objects, their position in space, etc.

We also need machines that would trace the entire process of machining. Some have been designed and are manufactured. Modern engineering thinking has created new automated coal-digging complexes and machine systems, installations for the continuous casting of steel, machine-tools for electro physical and electrochemical treatment of metals, unique welding equipment, automatic rotor transfer lines and machine-tool modules for flexible industries. New technologies and equipment have been designed for most branches of engineering.

In the shortest time possible the engineers are to start producing new generations of machines and equipment which would allow manufacturers to increase productivity several times and to find a way for the application of advanced technologies.

Large reserves in extending service life for machines can be found in the process of designing. At present, advanced methods have been evolved for designing machines proceeding from a number of criteria. Automatic design systems allow for an optimizing of the solutions in design and technology when new machines are still in the blueprint stage.

Applied mechanics

 

Mechanics is that branch of physical science which considers the effect of forces upon the motion or upon the conditions of material bodies.

Applied mechanics is a part of mechanics. It includes the laws of mechanics to be applied to the motions of particles and of rigid bodies as used in problems of engineering. The condition of rest is considered to be the limiting condition of motion.

It is assumed to classify a rigid body as a collection of material particles the distances between which are known not to be changed.

A particle is a body or a part of a body the dimensions of which are so small as to be negligible when compared with is surroundings or with its range of motion, so that the force acting upon it may be considered to be localized at a point.

The subject of applied mechanics may be divided into two parts statics and dynamics, and dynamics may be further divided into kinematics and kinetics. It is statics that treats that bodies in equilibrium, and dynamics that treats the particles and bodies in motion. Kinematics is the part of dynamics to treat the motion of particles and rigid bodies without reference to the forces that produce or change the motion. Kinetics is the part of dynamics to treat the motion of material bodies with constant or changed by the application of forces. The limiting case of bodies with constant velocity and therefore in equilibrium is sometimes treated in kinetics as well as in statics. In order to understand thoroughly such a subject as applied mechanics, it is necessary for the student to solve a number of problems. A problem in mechanics consists of a statement of certain known quantities and relations from which certain other unknown quantities or relations are to be determined.



There are three common methods of analysis of problems: the graphic method, the trigonometric method and the algebraic one. In the graphic method, the quantities are to be represented by corresponding lines or areas; the relations between them are to be represented by the relations of the parts of the diagram.

In the trigonometric method, the quantities are to be represented by lines or areas as well but they are not necessarily drawn to scale.

It the algebraic method, quantities are represented by symbols; the relations between them are shown by signs indicating the operations; and the solution of the resulting equations is made by algebra.

 

 


Date: 2015-12-11; view: 551


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