CMM Metrology: What It Is and What You Need To Know About It

If you’re new to CMM metrology, one of the first things you’ll read and hear about are coordinate measuring machines or CMMs. A CMM is a staple in a professional metrologist’s arsenal. It is one of the primary tools used to measure physical objects of various sizes, shapes, materials, and textures. If an object fits in a CMM’s measuring block, the CMM can analyze and measure its physical attributes. 

In this article, we’ll talk about the role of CMM in metrology, the different types of CMM in metrology, and why this tool is the most important in this field of study. 

What Is the Role of CMM in Metrology?

Metrology is vital in many industries because it ensures that production processes maintain a certain standard. In manufacturing, for example, metrology ensures that every product meets quality control standards – that they have accurate dimensions, shape measurements, colors, textures, and other physical features. Thanks to metrology, manufacturers can maintain the same quality and specifications across different production batches. 

CMMs are instrumental in the success of metrology because these are the tools used to verify the accuracy of the machines used in manufacturing and that the finished products meet the required specifications. 

Thanks to high-precision CMM tools, manufacturers across industries can:

  • Improve Quality Assurance (QA): Metrologists use CMMs to calibrate equipment like CNC laser cutters, assembly lines, bottling lines, etc. They do this to ensure that the machines used for manufacturing will always meet production specifications. All machines eventually succumb to wear and tear; without reliable quality assurance checks, their deterioration will only accelerate. 

For example, cutters become less accurate and smooth, and nozzles that dispense substrates into molds fall out of sync with conveyor belts. The slight deviations from the correct calibrations will add up until the products manufactured can no longer meet accepted tolerances.  

  • Maintain Quality Control (QC) Standards: Quality control ensures that the manufactured products meet specification requirements. Quality control staff look out for quality issues and check if the crucial physical features of a product are within tolerances. For example, they verify if the components created for assembling a car engine meet industry standards. 

Failure to meet these standards can result in serious legal consequences for the manufacturing company. Therefore, QC specialists must get accurate findings for their product quality assessments. CMMs are instrumental in these QC checks because they provide concrete, verifiable data about the assessed products.

  • Increase Production Efficiency: Production can become more efficient with regular machine calibrations and QA checks using CMMs. Furthermore, metrologists obtain the data necessary for designing and prototyping new products during these processes. Thanks to CMMs, metrologists can provide accurate and detailed measurements to the production floor, accelerating the process while lowering manufacturing errors and wastage. 
  • Comply with Industry Regulations: Manufacturing companies that must comply with industry regulations can successfully do so with the help of licensed metrologists who know how to use high-precision CMMs. Documentation and traceability are crucial to metrology, and CMMs are vital for both. Having the right measuring tools and specialists will enable manufacturers to meet industry regulations, especially regarding product safety.

What Are the Types of CMM in Metrology?

CMMs come in different sizes and configurations to accommodate a broad range of objects and applications. Here are the most widely used types of CMM in metrology:

  1. Bridge CMM: One of the most popular types of CMM for manufacturing, bridge CMM got its name because of its bridge-like design: two vertical support structures holding a horizontal bar, which has the measuring probe. The vertical supports of a small bridge CMM can move forward or backward on tracks on the floor, bringing the probe to measure the entire length of the object. 
  2. Gantry CMM: Gantry CMMs are the massive versions of bridge CMMs. They have the same structure – a measuring probe mounted on a horizontal arm held up by vertical supports on either side. However, given the massive scale of the gantry CMM (it is used to measure huge parts in automobile and aerospace manufacturing, for example), the horizontal arm is mounted on two massive tracks elevated by two or more pillars instead of just one on either side. Gantry CMMs are so massive that they are permanent fixtures on a production floor. Metrologists can measure an entire SUV and other equally huge objects using a gantry CMM.
  3. Horizontal Arm CMM: This CMM has the same scale as the gantry CMM but is less bulky and imposing. The horizontal arm CMM consists of two main components: a vertical arm holding up a thinner and an extended horizontal arm with a measuring probe on the end. This CMM is highly versatile because it can measure big pieces like car doors and automobiles. Two horizontal arm CMMs can work simultaneously to get a more comprehensive measure of massive, three-dimensional objects.
  4. Articulated Arm CMM: This is similar to the horizontal arm CMM but with an added feature. The horizontal arm that holds the measuring probe is longer, with a joint in the middle, giving the arm more flexibility to reach further around the object it is measuring. 
  5. Optical CMM: This refers to CMMs with probes that use optical sensors and cameras instead of a traditional touch probe. The advantage of optical CMMs is they can accurately measure the physical features of objects that may be too delicate or dangerous to touch with a physical probe. 
  6. Laser CMM: This refers to CMMs that use laser pointers to plot distinct points on an object’s surface to measure its physical properties. Like optical CMMs, laser CMMs are reliable for non-touch measurements. Additionally, laser CMMs are ideal for measuring immovable objects that are difficult to reach and distant surfaces that can’t be measured up close. 
  7. More varieties of CMMs combine one or more of the key features of the ones mentioned above. It is also possible to develop a custom CMM machine to accommodate a company’s unique measuring needs. Therefore, the range of CMMs currently used across industries is potentially endless.

Maximize the Uses of CMM in Metrology with ATT Metrology Solutions

CMM is valuable for companies that do manufacturing, packaging, or assembly. Its versatility is an added advantage because it enables companies to maintain QA, QC, and compliance standards even if they rapidly scale up on production. With the assistance of metrology solutions providers like ATT Metrology, manufacturers can achieve massive improvements in efficiency and quality if they maximize CMM technology.

ATT Metrology is a full-service metrology solutions company and one of the few in the world certified by Boeing and Airbus. If your operations hinge on the accuracy of measurements and calibrations, we are the perfect company to partner with. 

We are happy to offer rental services, equipment acquisitions, consulting services, and more. Contact us today to inquire about leasing, pricing, and consultations.