# Inspection Concept

On assembly lines, inspection is frequently used after part processing (such as dispensing, gluing, assembly, etc) to check the quality of the processed parts and exclude disqualified parts from flowing to the next station. The specific inspection items can very from presence check, to measurement, to gauging, etc. To meet different kind of inspection requirements, AlignPlus inspection function allows users to customize their own inspection items, and output each item's result status and value.

The figure below shows the measurement points needed for inspection after a film were assembled on to a panel part.

## Inspection Procedure

To execute inspection successfully and accurately, three steps needs to be taken care of: 1)Calibration, 2)Setup, 3)Run time. Calibration establishes a shared space for all cameras. Setup allows users to configure the AOI (Automated optical inspection) features finder and inspection items. Run time runs AOI feature extraction and their inspections on run time parts, and output the inspection results.

### Calibration

Inspection does not require motion, therefore it has no need to run hand-eye calibration, but just checkerboard calibration to calibrate all cameras into a shared space so that measurements among cameras can be conducted. However, if these cameras have already been hand-eye calibrated or cross calibrated using checkerboard plate, the AOI feature finder can also directly use these calibration results without extra checkerboard calibration, because checkerboard calibration result is already contained in these calibration results.

### Setup

There are two steps to setup an inspection vision task: feature extraction and inspection.

#### Feature Extraction

Feature extraction extracts AOI features such as points, line segments from images of a part. These features then will be forwarded to inspection task to check whether their result values or distances between meet specific requirements.

#### Inspection

AlignPlus inspection applications will generate a HMI for users to set up the following functions:

- Measurement

  Allows users to configure measurement types (such as PointToPoint, PointToLineSegment, LineSegmentToLineSegment) and their inputs, to measure distances between paired features. Users can also customize their own measurement tools with different inputs and outputs by implementing VisionPro toolblocks following requirements as described in Customize Measurement Types.

- Tolerance Setting

  Allows users to set the upper limits, lower limits, and offsets for every measurement results, and output OK/NG judgments for their tolerance check results.

After the setup, save the alignment recipe to save the feature extraction and inspection configurations.

### Run time

During run time, an external device can send inspection commands to the vision system to request images acquisition, feature extraction, and inspection to be done, and return the corresponding inspection results.