automated weld integrity analysis using 3d point data
DESCRIPTION
AUTOMATED WELD INTEGRITY ANALYSIS USING 3D POINT DATA. Matt Swanson, Eric Johnson, Alexander Stoytchev Iowa State University John Deere. Motivation. Bad welds are expensive Warranty claims Down time Current quality assurance methods are time consuming Hand measuring weld parameters - PowerPoint PPT PresentationTRANSCRIPT
AUTOMATED WELD INTEGRITY ANALYSIS USING 3D POINT DATA
Matt Swanson, Eric Johnson, Alexander StoytchevIowa State University
John Deere
Motivation Bad welds are expensive
Warranty claims Down time
Current quality assurance methods are time consuming Hand measuring weld parameters Procedure can take 1-2 hours for a single
weld
Results of Bad Welds
Some Weld Types
This Work Focuses on T-fillet Welds
Bad vs Good Welds
Previous Approach
Previous Approach
Previous Approach
Previous Approach
Dental Molding is applied Molding is cross sectioned
Previous Approach
Previous Approach
Previous Approach
R
Theta
Previous Approach The bending and the membrane
stress concentration factors of the weld are given by:
469.572. )(512.1 rtK b
t
469.37. )(388.1 rtK m
t
Our Approach (1) Scan the Weld
Powder weld with reflective
material
Aramis Camera Extract high
resolution 3D point clouds 50 micron resolution
Our Approach (2) Determine Geometry
Cluster Normals For every 3 neighboring points
(p,q,r)calculate vectors u and vu = q - p v = r - p K-means cluster on the plane
created fromthe cross product of u and v Fit Planes to Plate
Clusterscalculate plane from histogram of
green andblue clusters
Our Approach (3) Extract Weld Parameters
Slice Weld ClusterSlice weld along contour of the
interesection between the weld and plane
Fit Circle to Weld Toe Fit R1 and R2 Extract interior
points Circle fit
Results(Compare the two
Approaches)
Results (Slice #7 on Weld #1)
Results (Weld #1)
Results (Weld #1)
2.2% difference
Results (Weld #2)
1.9% difference
Video
ART Tracker
ART Tracker
Future Work Build a handheld device to scan
welds Couple a pico-projector with a web cam
Extend our software to scan entire assemblies and identify the welds on them automatically
Test under factory conditions
Summary and Conclusions
Questions?
