Namangan muhandislik qurilish

Key words: coordinate measuring machines (CMM), automotive industry, 
coordinate measurement methods, X, Y, Z coordinates, laboratory test equipment, 
testing, analysis, quality assurance, warranty period. 
Coordinate measuring machines (eng. CMM - Coordinate Measuring Machine) 
is a universal control tool designed for measuring geometrical parameters of objects 
and coordinates of surface points. A coordinate measuring machine (CMM) is a 
device designed to measure the geometric properties of an object. The machine can 
be operated by an operator or automated by a computer. Measurements are made 
using a sensor attached to the moving axis of the machine. Measuring sensors differ 
in the principle of operation (electrocontact, induction, optical, capacitive, 
piezometric, gravity device), output signal (analog, discrete), measurement method 
(contact, non-contact), type of measurement (scanning , trigger) etc. 
There are many types of CMM (Fig. 1). Traditionally, all types can be divided 
into three groups: Cartesian coordinate system, polar (cylindrical) coordinate system, 
special construction. 
Fig. 1 - SME structure 
a - portal; b - half-portal; v - bridged; g - horizontal pinole; d - console; ye - 
fixed; j – for control of twisting parts; z - measuring arm or robot; i and k are parallel 
kinematics 
CMM with Cartesian coordinate system includes [3]: 
Portal. Main features - P-shaped portal. main node and components have high 

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rigidity, accuracy, good dynamic characteristics, good visibility and convenience of 
the measuring zone. 
Half portal. Main features - G-shaped semi-portal. It combines the advantages of 
a portal structure with the ability to move along a vertical axis. SME is used to 
measure the average dimensions of a cube. 
Bridged. Its main features are that the arrows are attached to the columns on the 
table. This type of SME is used to measure large-sized details. 
Horizontal pinol (horizontal hand). The main features are that the horizontal and 
vertical axes move relative to the horizontal spindle. Easy movement of nodes, 
maximum openness of the measuring area. The disadvantage is the occurrence of 
errors due to the deformation of the spindle. 
Console. Its main features are the movable horizontal console. The disadvantage 
is the occurrence of errors due to the deformation of the console. 
Special construction CMM: 
Measuring hand (anthropomorphic construction). Main features - - hinged 
tubular elements. Many degrees of freedom, a wide measurement area, compactness, 
mobility. The disadvantage is relatively low accuracy. The main advantage of 
measuring arms is their mobility, which allows you to measure parts directly on the 
machine or on the spot. 
Parallel kinematics. Its main features are the use of parallel kinematics in the 
construction of moving elements. The ability to get six degrees of freedom using only 
three drivers. The CMM design ensures maximum adherence to Abbe's principle, 
which allows for high measurement accuracy.