Automated in-line object inspection
A system and method for performing real-time quality inspection of objects is disclosed. The system and method include a transport to move objects being inspected, allowing the inspection to be performed in-line. At least one optical acquisition unit is provided that captured optical images of the objects being inspected. The captured optical images are matched to CAD models of objects, and the matched CAD model is extracted. A laser with an illumination light beam has a wavelength in the violet or ultraviolet range then conducts scans of the objects, which are formed into three-dimensional point clouds. The point clouds are compared to the extracted CAD models for each object, where CTF are compared to user input or CAD model information and the object is determined to be acceptable or defective based on the extent of deviation between the point cloud and the CAD model.
1. A system for automated, in-line inspection of objects comprising:
a transport belt configured to move an object being inspected along a transport path;
an optical acquisition unit configured to capture an image of the object being inspected and to transmit object image data;
at least one laser module comprising a laser driver and at least one laser sensor configured to capture laser scans of the object being inspected by the at least one laser sensor and to generate point cloud data representing the object being inspected;
a system memory including a computer-assisted design (CAD) model database containing CAD models; and
a system processing unit configured to:
analyze the object image data and select a CAD model from the CAD model database corresponding to the object being inspected;
align the CAD model with the point cloud data; and
compare the point cloud data to the CAD model by determining whether respective deviations between one or more point cloud dimensions of the point cloud data and one or more CAD dimensions of the CAD model exceed one or more thresholds.
2. The system of claim 1 , wherein the system processing unit is further configured to determine whether the object being inspected is defective based on the comparison.
3. The system of claim 1 , wherein the at least one laser module is a laser profilometer having a wavelength in a violet or ultraviolet range.
4. The system of claim 1 , further comprising laser module guides restricting movement of the at least one laser module to predetermined directions with respect to the transport path.
5. The system of claim 1 , wherein the at least one laser module includes a first laser module and a second laser module, the first laser module and the second laser module each including a respective laser driver, at least one respective laser sensor, and a microprocessor.
6. The system of claim 1 , wherein the system processing unit is further configured to determine an angular relationship between a field of view of the at least one laser module and the transport path, and to perform a calibration based on determined differences in height between end points of the field of view due to the angular relationship.
7. A method for performing in-line inspection of objects comprising:
positioning an object to be inspected on a transport belt;
moving the object along a transport path using the transport belt;
capturing an optical image of the object with an optical acquisition unit;
capturing point cloud data representing the object with a laser module comprising a laser driver and at least one laser sensor;
selecting a computer-assisted design (CAD) model matching the object being inspected based on the captured optical image in comparison to a database containing CAD models; and
comparing the CAD model to the captured point cloud data by determining whether respective deviations between one or more point cloud dimensions of the captured point cloud data and one or more CAD dimensions of the CAD model exceed one or more thresholds.