Bushing Machining Inspection Application

Because bushings minimize friction and absorb vibrations, they are fundamental to automobile performance, safety, and comfort. This application focuses on bushing inspection after the machining process.

What manufacturing defects occur?

Factors such as tool wear and damage, improper machine settings, debris in the machining environment, and human error can cause defects during the machining process, such as:

Defect Description Consequence
Cracks Cracks in bushing material Compromised structural integrity; Reduced fatigue life; Increased wear; Potential failure of system using bushing
Scratches Linear grooves on bushing surface Compromised structural integrity; Increased wear; Reduced performance
Pits Shallow cavities or dents on bushing surface Reduced fatigue life; Increased wear; Reduced performance
Burrs Raised edges or slivers of material left behind Increased wear and tear
Heat Damage Warping, discoloration, or burn marks caused by excessive heating Reduced fatigue life; Compromised structural integrity
Dimensional Inaccuracies Does not meet specified size requirements Misalignment with mating components; Increased wear; Potential failure of system using bushing
Contamination / Inclusions Foreign materials embedded in bushing material during manufacturing Weak points; Possible bearing failure

These defects affect bushing performance, durability, and safety in their applications and manufacturers should implement quality control measures to prevent them.

However, these defects can be difficult to detect– bushing metal surfaces may reflect light in a way that masks defects. And many machining defects are subtle and hard to image, especially if the defect’s contrast to the background is low. Traditional machine vision systems struggle to capture clear images and distinguish between actual defects, reflective surfaces, and the background, ultimately missing defects or causing false rejections.

And in high-volume manufacturing environments, bushings must be inspected quickly to keep up with production rates. Traditional machine vision products may fail to keep up with required cycle times.

The Solution

UnitX’s AI-powered inspection effectively inspects bushing machining defects where other solutions fail.

First, the OptiX imaging system illuminates and images the bushings. Then, the CorteX Central AI platform is trained on machining defects. Lastly, those AI models are deployed to the CorteX Edge inference system to detect and classify defects in-line.

Alternatively, manufacturers can use just CorteX AI if they have existing imaging systems. For example, if a manufacturer wants to detect internal bushing defects such as inclusions embedded in the bushing material, they can deploy just CorteX AI and integrate it with existing X-Ray and CT Scanners for fast deployment of improved defect detection.

Why UnitX for bushing machining inspection?

OptiX provides superior images that minimize reflectivity while maximizing defect visibility. It has 32 independently controllable lighting sources that can be optimized for metal bushing surfaces and various defects via software. Its computational imaging capability can be used to take multiple shots and eliminate hotspots caused by highly reflective bushing surfaces. And its lighting dome design supports a very acute incidence angle of projected light, causing even very tiny defects to cast shadows which increase their visibility.

CorteX accurately detects random, complex defects. It automatically normalizes for variability in positions and orientations and recognizes defects down to the pixel-level. It reduces false positives that lead to scrap and wasted product.

CorteX supports fast AI model development, deployment, and iteration. CorteX AI models are sample efficient– they only require a few images to train on new defect types.

UnitX optimizes yield. In CorteX, can tune quality criteria and visualize the impact on yield before rolling those changes to production.  All inspection data is referenceable in one central platform for manufacturers to analyze and identify areas for process improvements.

UnitX provides rapid, 100% inline inspection. OptiX has bright LEDs and fast fly capture speeds of 1m/s for high speed imaging. And CorteX Edge supports high inference speeds (up to 100 MP) to quickly output an OK/NG decision, seamlessly communicating that decision via integration to all major PLC, MES, and FTP systems.

Manufacturers who use UnitX to automate bushing machining inspection are able to:

  • Prevent quality escapes that impact automobile reliability, performance, and safety
  • Reduce scrap by minimizing false rejection rates common with traditional machine vision and identifying defects early in the manufacturing process
  • Improve yield by analyzing production and quality data for process improvement opportunities
  • Automate inspection at the speed of their production to increase bushing manufacturing throughput

UnitX Inspection Example Deep Dive

In this example, we inspected metal bushings for surface defects resulting from the machining process. By inspecting bushings before the finishing process, we can catch defects early and minimize waste.

Imaging

First, we used OptiX to capture images of the bushings post machining, making sure we captured both defective and OK parts. We used OptiX’s software-defined lighting to configure various lighting patterns and incident angles that best captured the subtle defects.

Training

Next, we used CorteX Central to train our models. We created labels for the four bushing surface defects we wanted to detect: crack, scratch, dent, and abrasion. 

We then labeled those defects in the images we captured from OptiX, using just a few images for each defect.

Because of CorteX’s user-friendly interface and the low number of images it requires to train its AI models, it only took us a few minutes to complete the labeling for the four defects.

Detection

We then deployed those AI models to CorteX Edge to detect defects on new bushings, resulting in the accurate detection and classification of our four defects.

To learn more about how UnitX can automate inspection for you, please contact us here