Inspection at the Speed of Sound
Manufacturing in the era of nanotechnology requires processes that provide accurate information instantly. In the world of nanoseconds and nanometres, precision is essential.
A typical car assembly plant produces 300,000 cars a year. Three to four thousand resistance spot weld joints are made to ensure the integrity of the future car body at the assembly line. For an average inspector, it would take about seventy years to inspect all of welds made during just one day (three shifts). Could anyone or anything ever inspect all these billions of weld joints? The answer is yes—if the welds are inspected as they are being produced, in real time.
The Institute for Diagnostic Imaging Research, together with its industrial partners, (among them Chrysler, Centerline, and Magna), has developed a unique ultrasonic system capable of inspecting the weld at the moment it is produced. A special “acoustical eye” uses certain radar principles to look inside of the metal plates and observe the process of weld nugget growth and solidification in real time. The unique signal processing software and pattern recognition algorithms used for this process were developed to interpret the ultrasonic signals and to convert them into format readable by human. As the weld is produced, the robot knows whether it did a good job or not, and corrects itself.
This is technology which literally works at the speed of sound.