Concepts of Coordinate-Measuring Machine

A “Coordinate Measuring Machine” is a piece of equipment or device that measures the geometry of an object. It mainly measures the height, weight, width, and depth of a physical object. There are various types of CMM in the processing technology. The CMM has both advantages and disadvantages and the features and the uses of the CMM are very useful in the modern updated world because the CMM provides precise and accurate measurement of various objects.

Coordinate Measuring Machine

“Coordinate Measuring Machine” was first made in the early 60s. Originally, the first appearance of the CMM was developed by the “Ferranti Company” of Scotland. Ferranti first used the CMM to measure the precise components of the military products. The Coordinate Measuring Machine can easily measure the targeted object and record the accurate measurement. This machine can measure the geometry of difficult objects with accuracy. Most of the CMM machines are used to measure three-dimensional objects, such as for the measurement of automobile parts and different mechanical parts. 

Types of CMM

The Coordinate Measuring Machine is mainly classified into 5 types by its structure and features. Each type of CMM has its strengths and weaknesses. The five types of CMM are as follows-

Bridge CMM: This CMM is the most common CMM among the other CMM. It is divided between the movable table and bridge types. The Bridge CMM has a probing system that moves with three axes- the ‘x’, ‘y’, and ‘z-axis. All the axes have a sensor that maintains the position of the probes. It moves with the object and detects a point on the top of the object. It is one of the most proper CMM. The Bridge style CMM generally measures the small or midsize parts of the objects.

Gantry CMM: The Gantry CMM is similar to the Bridge CMM. This type of CMM is much larger than the others. That’s why these are used in the large products of automobiles and heavy parts of the machines. It is more costly than the other CMMs. It is highly accurate and easier to unload and load.  

Cantilever CMM: The Cantilever CMM is different from the other CMMs. These CMMs generally measure the small parts of the objects. It allows its parts to be accessed with the parts. Thus it is suitable for the measurement of the smaller parts of the objects. 

Horizontal arm CMM: The Horizontal arm CMM enlarges its probes horizontally rather than vertically. These CMMs are used to measure the long sides of the objects. They are not as accurate as the other types of CMMs. It is very cost-effective. 

Optical CMM: The Optical CMM is a portable and non-contact device. It acquires and scans the 3D measurement of the objects. It is easy to operate and portable and lightweight.

Advantages and disadvantages of CMM

Advantages of CMM: The advantage of the Coordinate Measuring Machine is that it can accurately measure objects that are generally difficult to measure. All types of CMM machines measure the height, width, depth, etc with high accuracy. For example, three-dimensional objects are very tough to measure but the “Optical CMM” can accurately measure the 3D objects. The other types of CMM can easily measure the exact measurement of any physical object. 

Disadvantages of CMM: Sometimes the CMMs may be costly to afford. Some CMMs have a fixed measurement volume and can take a lot of floor spaces. Some types of CMM are very sensitive and that’s why they may have a lack of portability. Among them, some are complex to handle easily and require a rigid setup. The “Portable measuring arm” and the “Horizontal arm” are less accurate than the other CMM. 

Features and applications of CMM

The main features and applications of the CMM are as follows-

• CMM has three main components, such as the machine, the measuring probe, and the control system with the measuring software.

• It is an important machine to protect the sensitive components of the objects.

• The software of the CMM supports the programming of the CAD model.

• The “reverse engineering” of the CMMs mainly captures the geometry of a proper object. 

• The “SPC software” of the CMM measures and analyzes the statistical measurement.

• A CMM has sufficient capacity that’s why it can easily fit an object.

• The higher resolution of the CMM denotes the more specific measurement.

Conclusion

It can be concluded that the entire chapter has discussed the topic “Coordinate Measuring Machine”. The chapter has given an outline about the types of Coordinate Measuring Machine, the advantages and disadvantages of the CMM and it has also described the features and the applications of the “Coordinate Measuring Machine”. The features and the uses of the CMM are very useful in the modern era. This machine can measure the geometry of difficult objects with proper accuracy.