[공정소개] 접촉식 3차원 측정: 정밀한 부품 검사와 품질 보증의 열쇠

1. Basic Principle of Contact-Based 3D Measurement

The basic principle of contact-based 3D measurement is that a probe comes into direct contact with the surface of the object to record the X, Y, and Z coordinates of specific points. These coordinates are then used to reconstruct the object’s geometry, dimensions, and other characteristics in 3D space. The process generally follows these steps:

• Probe Contact: The probe of the CMM contacts the object’s surface, recording the coordinates of that point.
• Coordinate Collection: The probe moves across the object, touching multiple points and recording the 3D coordinates at each contact.
• Data Processing: The collected coordinate data is processed by software, which analyzes the object’s geometric features, dimensions, and tolerances.

2. Contact-Based Measurement Equipment: CMM (Coordinate Measuring Machine)

The CMM is the most widely used equipment for contact-based 3D measurement. Key features of CMM include:

• Structure: CMMs have a moving structure along the X, Y, and Z axes, which allows them to measure an object from various angles and positions.
• Probe: The probe is a tool attached to the CMM, which comes into contact with the object’s surface to record its coordinates. The probe can be mechanical or electronic and may vary in design, depending on the application.
• Software: The CMM is connected to specialized software that processes and analyzes the collected data. The software automates tasks like dimensional inspection, geometric analysis, and tolerance verification.

3. Process of Contact-Based 3D Measurement

The process of contact-based 3D measurement typically follows these steps:

1. Object Preparation: The object to be measured is placed on the CMM machine, and it must be properly fixed in place. If the object moves during measurement, the data will be inaccurate.

2. Measurement Path Setup: The measurement path is set up through CMM software. The path is designed to measure the key points of the object or the areas requiring inspection.

3. Probe Contact: The probe moves along the defined path and contacts various points on the object’s surface. The 3D coordinates of these points are recorded, which helps in creating a digital representation of the object’s shape.

4. Data Analysis: The collected 3D coordinate data is processed by the software. The data is then used to inspect the object’s dimensions, geometric features, and verify if the object meets design specifications and tolerances.

4. Advantages of Contact-Based 3D Measurement

Contact-based 3D measurement offers several advantages:

• High Accuracy: This method provides precise data, especially for detecting small deviations in dimensions or shape. It is highly reliable for dimensional measurements.
• Capability to Measure Complex Shapes: Contact-based measurement can accurately measure complex geometries and shapes, such as intricate curves or internal features of an object.
• Quality Control and Verification: Contact-based measurement is essential for quality control, ensuring that manufactured parts adhere to design specifications and identifying defects or deviations early in the production process.

5. Disadvantages of Contact-Based 3D Measurement

However, contact-based 3D measurement also has some limitations:

• Time-Consuming: Since the probe must contact each point individually, the process can be slow, especially for large or intricate parts.
• Potential for Surface Damage: The probe physically contacts the object’s surface, which may cause damage to delicate or soft materials. Careful handling is required for sensitive parts.
• Limited Speed: The measurement process is generally slower than non-contact methods, making it less suitable for high-throughput, mass-production environments where speed is a priority.

6. Applications of Contact-Based 3D Measurement

Contact-based 3D measurement is widely used across various industries for precise inspection and quality control:

• Automotive Industry: Used for measuring the dimensions and shapes of automotive parts. Components like engine parts, chassis, and body panels require high precision, making contact-based measurement an essential tool.
• Aerospace Industry: Critical for measuring aerospace components, where precision is paramount. Parts like engine components, turbine blades, and structural elements are commonly inspected using CMMs.
• Electronics Industry: Used for inspecting electronic components, such as printed circuit boards (PCBs) and other small, precise parts. Ensuring the correct dimensions and geometry is vital for proper functionality.
• Precision Machinery: Used in the manufacturing and inspection of precision mechanical parts. The high accuracy required for gears, shafts, and other mechanical components makes contact-based measurement indispensable.

7. Conclusion

Contact-based 3D measurement is a highly accurate and reliable method for inspecting the dimensions and geometry of objects. It plays a critical role in industries such as automotive, aerospace, electronics, and precision machinery, where dimensional accuracy and quality control are essential. While it can be time-consuming and may cause surface damage to sensitive parts, its precision makes it indispensable for applications requiring the highest levels of accuracy.