How Laser Tracker Inspection Ensures Precision in Manufacturing

Laser tracker inspection is a valuable technology for ensuring precision in manufacturing processes. This advanced measurement system uses a laser beam to accurately measure the three-dimensional coordinates of an object. This allows you to obtain highly precise data that can be used for various quality control and alignment tasks.

Laser tracking systems are capable of measuring with extreme accuracy, often within micrometres. This level of precision is critical in industries where small deviations can lead to significant issues, such as aerospace, automotive, and high-precision machining. By using a laser interferometer or Absolute Distance Meter (ADM), laser trackers can measure distances with high precision, ensuring that parts are manufactured to exact specifications.

By providing precise, reliable, and versatile measurement capabilities, laser tracker inspection helps you ensure that your products meet stringent quality standards and are produced efficiently. This is a critical component of modern quality assurance in manufacturing, helping to reduce errors, improve product quality, and enhance overall productivity.

Understanding the accuracy and precision of laser trackers is crucial for making informed decisions about their use in your projects. In this article, we’ll explore how laser tracker inspection ensures precision in manufacturing.

Measurement accuracy

This can fall into two categories, the first being linear accuracy. This refers to the closeness of the measurements to the actual value. For laser trackers, linear accuracy is typically specified over a certain distance. For example, a specification might state an accuracy of ±10 micrometres at a distance of 10 metres. This means the measured position can deviate by up to 10 micrometres from the true position at that range.

Then there’s angular accuracy, which defines the precision with which the laser tracker can measure angles. This is crucial for determining the orientation of components. Angular accuracy is usually specified in arcseconds (1 arcsecond = 1/3600 of a degree). For instance, a tracker might have an angular accuracy of ±1 arcsecond, indicating a very fine level of angular measurement.

Repeatability

Firstly, single point repeatability measures the laser tracker's ability to return to the same point in space after repeated measurements. It's an indication of the consistency of the device, often specified in micrometres. For example, a repeatability of ±2 micrometres means the tracker can reliably return to the same point within a 2-micrometre range.

The volumetric accuracy represents the accuracy across the entire measurement volume. It's a combination of linear and angular accuracies, providing a more comprehensive picture of the system's overall accuracy.

Environmental conditions

The environment can affect decisions around the right laser trackers in various ways. Many laser trackers include systems to compensate for temperature changes, which can affect measurement accuracy. It’s important to know the operating temperature range, and the device’s ability to compensate for thermal expansion, for ensuring accurate measurements in varying conditions.

Accuracy can also be impacted by the sensitivity of the laser tracker to environmental factors, such as humidity, vibration, and air pressure. Specifications might include permissible ranges for these factors.

Measurement range

Know the maximum distance over which the laser tracker can accurately measure. For instance, some trackers can measure up to 80 metres or more. This is vital for planning measurements in large-scale projects.

You or your service provider should also check the minimum range, which is the closest distance at which the laser tracker can effectively operate. This is crucial for projects involving small-scale components or fine details.

Calibration and certification

The calibration frequency gives information on how often the laser tracker needs to be calibrated to maintain accuracy. Regular calibration ensures the device's measurements remain reliable over time.

Check the traceability too, which is the ability of the measurements to be traced back to national or international standards. This is essential for quality assurance and compliance with industry standards.

Data resolution

The resolution indicates the smallest detectable change in measurement. A higher resolution indicates finer measurement capability. For example, a resolution of 0.1 micrometres means the tracker can detect changes as small as 0.1 micrometres.

Real-time data collection

Laser trackers provide real-time data collection, which allows for immediate feedback and adjustments during the manufacturing process. This capability is crucial for identifying and correcting errors as they occur, reducing the risk of defective products and minimising waste.

Measurement uncertainty

The measurement uncertainty encompasses all potential errors in a measurement, including equipment, environmental, and procedural errors. Understanding the total uncertainty helps in assessing the reliability and validity of the measurement data.

Performance specifications

The dynamic performance gives information on how the laser tracker performs under dynamic conditions, such as tracking a moving target. This includes the maximum speed of target movement that can be accurately tracked.

Versatility and range

The flexibility of laser trackers allows them to measure objects of various sizes and shapes, from small components to large machinery. They can operate over long distances, often up to several tens of metres, making them suitable for large-scale manufacturing environments.

3D measurement and alignment

Laser trackers can perform three-dimensional measurements, which are essential for ensuring the proper alignment and assembly of parts. They are often used in conjunction with software to align machinery, calibrate tools, and verify the dimensional accuracy of components. This capability ensures that assemblies are built correctly and will function as intended.

Non-contact measurement

As a non-contact measurement system, laser trackers do not physically touch the parts being measured. This is particularly important for delicate or sensitive components that could be damaged by contact. Non-contact measurement also avoids the introduction of mechanical stress, or deformation that could affect the accuracy of measurements.

Automation and integration

Laser trackers can be integrated into automated manufacturing systems, allowing for continuous monitoring and inspection. This integration supports high-speed production lines. By providing rapid, accurate measurements without manual intervention, they support consistent product quality.

Data logging and analysis

The data collected by laser trackers can be logged and analysed to improve manufacturing processes. This information can be used for statistical process control, trend analysis, and root cause investigation, helping you to continuously improve operations and maintain high-quality standards.

Data processing software shows the capabilities of the software used for data analysis. This includes how it handles data correction, filtering, and visualisation. Understanding the software's features helps in assessing the ease of use and accuracy of data interpretation.

Complex geometries and large-scale metrology

In industries like shipbuilding and aerospace, where large structures and complex geometries are common, laser trackers are invaluable. They enable precise measurement of large components, ensuring that they fit together perfectly and perform as required.

Get in touch today if you want to speak to us about laser tracker hire, or our laser tracker inspection services.