May 2022 Volume 4

AUTOMATION

This automated robotic spacer line worked very well with the general scheme of FRISA’s fully automated production line. The key was creating a more sophisticated program to accommodate the high variability of parts being handled on the line. It was a great success and a model for other applications since then. Another advantage of using robot XYZ coordinates calculated off of a single fixed point is the ability to make on the fly adjustments. For instance, we have used the HMI outside of the safety cell to allow the operator to adjust the drop position of parts in a press on the fly. Of course, as dies wear, there can be a need for this. There are many other advantages to this type of robot programming technique, such as robot recovery from non-standard stoppages and manual control from outside the safety cell via an HMI. Creating a more sophisticated robotic control program with mathematical referenced based off of a single point can be a significant advantage for your line automation. Using one or a few key points to teach the robot and basing other positions off of these key points can make life easy for those who work with the automation on a regular basis. Often times, there are one or two key people that are trained and able to effectively use the teach pendant for the robot. If one of these key people are unavailable, production is delayed. Our goal is to make a simple robust line that makes job changes easy and on the fly adjustments possible. In short, productivity is maximized when the automated line is simple to use and optimized for the specific work environment and available talent.

FRISA is a world class producer of rolled rings for industry and aerospace that has been a leader in the installation of fully automated production lines. One of the challenges for automation of the ring production industry compared with automotive applications is that typically, there are not high volumes of identical parts. This means that in a given shift, the automationmust be able to adapt to a variety of different part geometries. Almost all robots are suppliedwithwhat is known as a teachpendant. Using this pendant, the maintenance and operator team can adjust the points where the robot picks up and drops off the parts. In this way, the program is a relatively simple path of points that can be touched up by the teach pendant. While it is convenient to adjust point positions by the teach pendant, there are some disadvantages. Adjusting points by a teach pendant is a manual operation, but there are six co-ordinates associated with each point. There are the XYZ spatial coordinates and the roll, pitch, yaw orientation coordinates. These coordinates are difficult, if not impossible to exactly duplicate when manually adjusting these points. There are advantages to this simplicity, but taking the time to adjust or touch up points between jobs is not always practical. FRISA presented our engineers with a challenge to be able to place spacers on a hot ring before being stacked by an automated crane for heat treating. The challenge was that almost every ring coming down the line required a different placement of spacers. Some required six spacers, others required 12 spacers. The rings were different diameters. Some rings had axial profiles on the OD, some on the ID, and others hadmiddle diameter axial profiles that needed two spacers. The spacer placing robot needed to communicate with the ring turntable and the stacker crane as well. FRISA had the goal of making this line 100% automated. It just wouldn’t do to have a person grab the teach pendent and enter the cell between jobs. The secret to this job was to pick a fixed point of reference and make all pickup and placement points a mathematical function of the fixed point. The center of the ring turntable was the logical choice for a fixed point of reference. The turntable had centering arms to make sure the ring was in place. Then, all the robot spacer drop positions could be calculated based on the center of the ring, the diameter, and the position of axial profile. There was ONLY one point to teach, the center of the turntable! Robot Placing spacers on hot ring with outer diameter profile after installation of aluminized kevlar suit. Source: Courtesy of FRISA

Robot Placing spacers on hot ring with outer diameter profile. Source: Courtesy of FRISA

Michael O’Toole Vice President Forging Equipment Solutions Phone: 216-272-4891 Email: mikeo@forgingusa.com

FIA MAGAZINE | MAY 2022 33