Study of Surface Porosity Using Reconfigurable Inspection Machine (RIM)

The University of Michigan, Ann Arbor

NSF Engineering Research Center for

Reconfigurable Manufacturing Systems

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

Surface Porosity Inspection – Research Objectives

• Establish a methodology necessary for non-contact inspection of porosity defects.

• Determine if the above methodology can reliably detect porosity defects according to GM/DCX specifications.

• Determine if the above methodology can be implemented in-line (i.e. at line rates).

• Validate the method with production cylinder headsand blocks.

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

• Areas on the deck face of an engine cylinder head are isolated one from the other to prevent the mix of water, oil and combustion

gasses.

Fire ring

Sealing Bead

Gasket body

Background: Why Inspect Engine Cylinder Heads ?

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

Porosity Inspection is Currently Performed by Human Inspectors

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

Vision Sub System for Porosity Inspection

Reconfigurable Inspection Machine (RIM)

U.S. Patent #6,567,162 B2 Yoram Koren, Reuven Katz

Vision Sub System for Porosity Inspection

Illumination System

CCD Line Scan Camera

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

Controller Module Inspection Module

System Operation

Vision System

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

Easy to use User interface and Automatic Analyze and Decision

Zoom Window for Pore Analysis

Defects Highlighted

in Red

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

Surface Porosity Inspection Study Achievements (1 of 2)

• Developed a Reconfigurable Inspection Machine (RIM) for porosity inspection on cylinder heads.

• Developed algorithms, software for detecting and classifying surface porosity. (Able to classify pores by diameter, x-y location, and specification region.)

• Conceptualized a method for depth validation of detected pores using side lightning.

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

Surface Porosity Inspection Study Achievements (2 of 2)

• Able to detect pores with diameter > 300 micrometer.

• Able to detect isolated and edge-connected pores on aluminum and cast-iron parts.

• Created a user-friendly software interface for reporting and analyzing defects.

• Created a software tool for assessing the repeatability of the porosity inspection system.

• As a result of this research GM built an inspection machine and DCX is testing it in a plant.

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

System Evaluation at GEMAOver 600 engine blocks were inspected by the RIM. 85% of bad parts were correctly rejected. (15% missed detections due to defects other than pores and template misalignment)90% of good parts were correctly accepted. (10% false alarms mainly due to template misalignment)

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

Future work

Inspection of porosity on pistons and cylindrical parts

Defect inspection on auto-body panels

Combustion chamber volume measurements

Improvements of RIM performance reliability

NSF Engineering Research Center for Reconfigurable Manufacturing SystemsCollege of Engineering, University of Michigan

04/21/23

The End

Questions are welcomed