Machine vision has become an integral part of modern manufacturing.
The major components are
- Machine Vision Software
- Statistical Process Control Software
- Mechanical Fixturing
- Computer Hardware
- Calibration Standards
One of the major advantages in Machine Vision Inspection is that we can undertake 100% percent inspection along with practicing real time process control enabling us to look at see that the process is in control as well as center the process.
Machine Vision in an ideal situation has to be incorporated during the machine design stage.
We have to build in open or closed loop feed back system to center the process as well as see whether the process is in control.
We must have a clear understanding of the parameters to be measured using detailed drawings, documented acceptance criteria and reject mechanism.
The camera and software is fairly easy to choose with the excellent products available from major vendors.
Attention has to be paid to choosing the correct light as well as robust mechanical mountings couple with a very defined calibration strategy using NIST traceable standards.
The next stage is validating the process. Structured validation will reveal flaws in the camera software tools and can be corrected at the beginning.
Real time SPC can help the operators monitor the centering of the process and use the open or closed loop function to control the process. Alarms will indicate if the process is out of control which in turn can trigger preventive and predictive maintenance.
Process improvement and trouble shooting for false rejects or accepts is easy with the facility to log data as well as capture images .
For example the systems can be configured to log data from the measured parameters during a run as well as capture images both for passed or rejected parts. This data can be analyzed with Excel or Minitab to look at abnormal conditions. We can also rerun the captured images frame by frame to see if any of the camera software tools have failed. This will in turn trigger corrective action. Excel & Minitab graphs are excellent presentation aids to present gain made in process improvement initiatives.
In fact with the competitive price structure for machine vision inspection products in the market the is no reason to do any manual inspection for mass produced products.