May 2021 Volume 3

AUTOMATION

Important Considerations When considering robotic billet bin picking systems using vision it is important tomake sure that the lighting in the area remains at the same levels at all time for the system to properly identify the billets in the bin. For example, opening an overhead door near the equipment can result in erratic image capture which will impact the ability of the system to properly identify the billets in the bin. The lighting at the time of adjustment should remain the same during all times of operation. Also, consider the range of billet diameters and overall lengths andmake sure that they are within the capability of themachine.

to be completely emptied. To better empty a tote, generally the tote can be tilted towards the robot.The bottom of the tote, which is now angled, results in the billets rolling or moving down to the lowest area making it possible to completely empty the tote bin. Bear in mind the tote bins must always be placed in a fixed position. Guide angles can be applied to facilitate the placement of a replacement bin into the cell. Mounting the area sensor above the tote bins allows the sensor to be moved over from the first bin to the second via a linear actuator.This saves the expense and integration of a second device. This overhead design allows for the fastest possible cycle time as the area sensor can now take images while the robot continues in motion with no lost time. Mounting a smaller area sensor to the robot arm is also an option, but bear in mind the robot must stop its motion above the bin and capture an image, and this takes time to accomplish. Additional Functions In addition to picking random billets from a tote and placing them onto the in-feed conveyor of the induction heating system, robotic billing loading systems can also have other functions such as checking the size of each billet and/or verification of the material. The robot can pick and place the billet onto a V-shaped holder fitted to a weigh scale at the end of the conveyor. This V-shaped holder also serves the same function as a repick station. The angled side walls and gravity results in the billets dropping into perfect alignment of the billet prior to pushing it onto the infeed conveyor. The billet is weighed while in this fixture prior to being pushed onto the end of the conveyor chain as the robot moves to pick the next billet, with no loss of time to align the billet. If the billet is not within the weight tolerances it can be rejected from the top of the scale, off of the side and down a chute into a smaller tote bin. If time and tolerances permit, the robot can also pass the billet in front of a 2D camera which can determine the diameter and overall length of the billet and check to see if it is within the proper range.

Area Scanner Captured Image

Summary Billet bin picking is not a new technology. Ajax TOCCO has been doing this since 2009 and awarded a patent for this technology, US Patent 2009/011694.0. Today there has been more emphasis on this technology, as the technology has improved dramatically due to the further development of smaller higher speed area scanners that provide a 3D detailed map in less than 1 second. In using a robotic bin picking system, a forge is able to reap the following benefits: 1. Reduce noise to a minimum. 2. Eliminate dust. 3. Reduce floor space to a minimum. 4. Verify weight of billets in-line. 5. Reduce maintenance cost. 6. Eliminate loading labor costs. ■

Joe Stambaugh, Segment Leader Forging Products Group, Ajax TOCCOMagnethermic Corporation, Warren, Ohio. Video of robotic billet picking available upon request. Please contact Joe Stambaugh for more information. Email: jstambaugh@ajaxtocco.com Phone: 614-440-0945 Special acknowledgement to FANUC America and Laura Evans, Sr. District Account Manager FANUC America.

Robotic Billet Picking Using Magnetic End Effector As the billets move onto the fast-moving chain conveyor, they can also be fed through an eddy current testing device to further test the material composition of the billet.

FIA MAGAZINE | MAY 2021 15