Radian Laser Tracker Precision Measurement Solution in Narrow Spaces

Laser Tracker and precision measurement

Laser trackers have been recognized by the industry as a solution that can provide reliable 3D/6D data in various aspects of large-scale precision measurement, and are widely used in production and manufacturing in various industries, including aerospace, automotive manufacturing, shipbuilding, energy facilities, construction engineering, national defense and military industry, scientific research institutes, and so on.

The rich functions of laser trackers in large-scale and large-scale environments have been well known in the industry. In this case, we will analyze and discuss the measurement solutions of laser trackers in narrow spaces, in order to further enrich and expand the usage ideas and application fields of laser trackers.

Case Overview
The measurement requirement of this case is to measure a slender rod with a length of 4500mm and an inner diameter of 80mm, perform high-precision measurements on the inner diameter busbar, evaluate its straightness, cylindricity, coaxiality, and other related data.

Measurement difficulties

The measurement difficulty of this case lies in conducting measurements in a narrow space, while also requiring flexible and smooth target ball control. Data is collected from various test points inside the thin rod for analysis, providing data support for manufacturing.

API Solution
For this type of measurement operation, API has developed a tracker fixture attachment specifically applied to narrow spaces. The fixture attachment consists of an SMR fixed base, spring, top screw, and fixed rod (refer to Figure 2). According to actual scenarios, various models of SMR target balls can be adsorbed and fixed on the fixture to measure the internal parts of the thin rod to be measured.
Summary of measurement process
1. Erect the laser tracker at a suitable position within the observable rod to be tested;
2. Further fine tune the position relationship between the workpiece and the tracker, so that the laser can pass through the inner diameter space without being obstructed. Then measure the end of the workpiece and establish the workpiece coordinate system, so that the axis of the coordinate system (which can be set as X, Y, or Z axis according to the actual situation) follows the axis direction of the workpiece;
3. In conjunction with the fixture attachment, place the SMR target ball into the interior of the workpiece to be tested for measurement. During measurement, the spring and top wire located on the fixture will work together to exert top pressure, keeping the SMR target ball in real-time contact with the inner wall of the workpiece to be tested (refer to Figure 3), in order to measure effective data that meets the standards;
4. By using the cross section measurement function of the Measurement Software, the SMR target ball is moved along the axis through the tooling. When passing through the preset corresponding cross-section (such as X=100, 200, 300), data is automatically collected;
5. Measure other required data, complete data processing and evaluation work.
Flexible application of SMR tooling
The SMR fixture attachment in this case has a segmented and quick installation structure with pull rods that can be added or removed according to actual needs, facilitating the implementation of measurement operations. In addition, when measuring blind holes, an eccentric pull rod can also be matched and fixed at the front end of the fixture. Follow the above operating steps to achieve accurate measurement of the interior of the blind hole.
conclusion
The Radian laser tracker, in conjunction with SMR and tooling, perfectly solves the problem of high-precision 3D measurement in narrow spaces inside slender rod shaped workpieces. The various laser tracker function expansion attachments independently developed by API have received high praise from users from various industries, greatly expanding the application field of laser trackers.