Repeatability Validation

This section describes how to verify the repeatability of an inline measurement system before go-live.

Repeatability reflects the repeat precision of the measurement system, indicating how consistent results are under the same conditions. Repeatability directly affects reliability and stability of inline measurement results. Therefore, repeatability validation must be performed before go-live to ensure the system can continuously output stable and trustworthy measurement results, meeting the needs of subsequent data analysis and quality control.

Phase Goal

The goal of this phase is to confirm that the system provides repeat precision that meets project requirements under static, semi-dynamic, and dynamic conditions.

Entry Criteria

Before starting repeatability validation, it is recommended that the following conditions have been met:

  • System hardware, network, and project configuration are completed.

  • Joint debugging of the robot, Mech-MSR, and Mech-Metrics has passed.

  • The measurement workflow runs stably and can continuously output result data.

Repeatability testing

Repeatability testing refers to performing multiple measurements of the same measurement target or object under the same conditions, to assess the consistency of the measurement results.

Static repeatability testing

In static repeatability testing, the part is fixed in place using a fixture. The robot, equipped with a camera, moves to the measurement position of the part’s feature. At this position, the robot remains still while the camera captures multiple images of the feature. For example, if a part has 5 features, the static repeatability testing is performed as follows:

  1. Secure the part: Secure the part using a fixture.

  2. Move the robot: Move the robot to the position of Feature 1 on the part.

  3. Capture images: The camera captures 20 images of Feature 1 until the test for this feature is complete.

  4. Repeat the process: Repeat steps 2-3 for the remaining 4 features. The static repeatability test for the current part is then complete.

Semi-dynamic repeatability testing

In semi-dynamic repeatability testing, the part is fixed in place using a fixture, and the robot, equipped with a camera, moves sequentially to the measurement positions of each feature on the part and takes photos. After completing one round of photo captures, the same operation is repeated to complete the remaining rounds. For example, if a part has 5 features, the semi-dynamic repeatability testing is performed as follows:

  1. Secure the part: Secure the part using a fixture.

  2. First round of photo capture: The robot, equipped with the camera, takes photos of all the features on the part in sequence (Feature 1 → Feature 2 → Feature 3 → Feature 4 → Feature 5).

  3. Repeat the process: The robot repeats step 2 for the remaining 19 rounds of photo captures. The semi-dynamic repeatability test for the current part is then complete.

Dynamic repeatability testing

In dynamic repeatability testing, the process is similar to semi-dynamic repeatability testing, except that the part is re-clamped at the beginning of each measurement round. After the part is clamped and secured, the robot, equipped with a camera, moves sequentially to the measurement positions of each feature on the part and takes photos. For example, if a part has 5 features, the dynamic repeatability test is performed as follows:

  1. Secure the part: Secure the part using a fixture.

  2. First round of photo capture: The robot, equipped with the camera, takes photos of all the features on the part in sequence (Feature 1 → Feature 2 → Feature 3 → Feature 4 → Feature 5).

  3. Re-clamp the part: Re-clamp the part.

  4. Repeat the process: Repeat steps 2-3 for the remaining 19 rounds of photo captures. The dynamic repeatability test for the current part is then complete.

Mech-Metrics provides repeatability test functions, including static repeatability testing, semi-dynamic repeatability testing, and dynamic repeatability testing. Verify them one by one to ensure the system meets measurement requirements.

Core Tasks

In this phase, it is recommended to complete verification in the following order:

  1. Perform a static repeatability test to confirm system stability under ideal conditions. For details, refer to Test static repeatability.

  2. Perform a semi-dynamic repeatability test to confirm system stability under partial-motion conditions. For details, refer to Test semi-dynamic repeatability.

  3. Perform a dynamic repeatability test to confirm system stability under the full production cycle. For details, refer to Test dynamic repeatability.

  4. Compare test results against project requirements and determine whether conditions are met to proceed to the next phase.

Completion Criteria

After this phase is completed, the following conditions should be met:

  • Static, semi-dynamic, and dynamic repeatability results are all obtained.

  • Repeatability results meet project agreement or acceptance requirements.

  • If results do not meet requirements, the root cause has been identified and corrective actions have been closed.

  • After Repeatability Validation passes, proceed to the Correlation analysis and compensation phase.

Is this page helpful?

You can give a feedback in any of the following ways:

We Value Your Privacy

We use cookies to provide you with the best possible experience on our website. By continuing to use the site, you acknowledge that you agree to the use of cookies. If you decline, a single cookie will be used to ensure you're not tracked or remembered when you visit this website.

  • Preference
  • I accept
  • I don't accept