The manufacture of automotive disc brakes is a physically demanding and challenging process requiring advanced tracking capabilities. Alber Gussbearbeitungs-GmbH has developed a fully automated brake disc surface flattening and testing process that ensures the highest quality products and reduces the workload for employees. Integrated machine vision provides process vision and reliable alphanumeric character reading (optical character recognition) using modern vision systems.
Today's automotive parts manufacturers are no longer content with simply producing top-of-the-line precision components. Many manufactured components must be traceable throughout the production process to ensure complete reliability; to address this challenge, Alber employs two Cognex In-Sight® intelligent vision systems to read the alphanumeric codes on rotary disc brakes. This not only enhances process safety but also reduces the workload for employees performing strenuous tasks.
Difficult times
Automotive disc brakes weigh approximately 12 to 20 kg (26.5 to 44 lbs). Before Alber adopted Cognex machine vision technology, employees had to repeatedly lift the heavy discs from stainless steel cases and place them on various inspection tables. Performing this strenuous work posed health hazards to workers on the production line. Now, this is no longer a problem, as the turning and cutting processes for downstream surface smoothing operations, as well as inspection work, have been fully automated.
To automate this process, automation experts from CNC Automation Würfel GmbH collaborated with image processing experts from i-mation GmbH to teach the Yaskawa Motoman MH50-35 robot how to view.
Keen vision
An In-Sight vision system is directly mounted on the head of the clamps. With its automated focusing, rapid image acquisition, and built-in illumination, the fully integrated smart camera identifies the position of the disc brakes conveying along the conveyor belt. The camera aligns it with the inner diameter and then transmits the image data to the robot within fractions of a second for control, allowing the high-performance magnets to quickly clamp the disc.
After clamping the disc brake, the first step is to read the alphanumeric characters. To perform this step, the robot places the disc brake on a rotating disk. Another In-Sight system reads the alphanumeric characters, focusing them with its integrated red LED. A high-speed 1K In-Sight line scan imager captures the pixelated embossed characters as the disc brake rotates twice.
Reliably reading different embossed characters is one of the most challenging tasks machine vision experts encounter with i-mation, because the embossing types in product batch numbers vary. i-mation overcomes this challenge using a step-by-step teaching procedure covering all possible variations. Cognex's high-performance OCRMax™ graphics processing tool for OCR applications, along with the user-friendly In-Sight Explorer software, makes it even easier.
Precise positioning
After reading the alphanumeric characters, surface flattening and inspection steps are performed, including balance and sound tests. Finally, the robot creates a stack of trays in six stainless steel boxes and then places wooden lids on top. The robot's in-sight camera uses a simple black crosshair to pinpoint the exact location.
Creating a safe future
The fully automated disc brake handling system and the two Cognex machine vision systems are both firsts for Alber, and they play an extremely important role in automating the product line and reducing the workload of employees.
