Students: Emre Gözcü, Donizetta Daffa Aqilla Harley, Lauri Tuomaala & Aurelia Adventa Ayuprashinta
Introduction
SILICON is a metal fabrication company, designing and manufacturing a wide range of specialist heat-resistant anchors for use in the petrochemical, cement, incineration, steel, and power industries. The company is in Wateringen, the Netherlands.
Current situation
To make one complete heat resistant anchor, two different kinds of pieces are assembled and finally assembled together. Anchors and pins come in separate cardboard boxes and a person must pick them from the boxes and place them into a assembling machine in a certain order. This process is done by one person.
The Problem
The main problem was to find an efficient way to assemble heat resistant anchors continuously with automated solution. Rising labor costs and difficulties to find a person for this kind of repetitive job is not always an easy task. Also, when working with machines with moving parts the risk of injuries is also present and wanted to be minimized as much as possible.
When handling anchors, it was common that they get tangled together with another anchors. Only pins did not have this issue due to its simple design.
Solution
When finding a solution for picking and placing objects, automation and robotics might come first into mind, and this is what the project group aimed. Our solution involved singulation for the anchors so they can be picked up in a certain position and removing the issue with tangling. A cobot (collaborative robot) arm for picking and placing pins and anchors, and finally a assembling machine to make a full product.
For the anchors, we modified the existing bowl feeding machine from the company to meet our requirements. We added metal wire on the sides of the bowl so anchors can only move in a certain position trough the line of bowl.
For the orientation of anchors, we welded pieces of steel together and made the slope so anchors can only fall on a certain side.
We also used a linear feeding machine at the end of ramp connected to the bowl. The reason behind this was to minimize the vibration, but still have it so anchors can still move to the end of the ramp. The ramp had to be separated from the original situation where the ramp was solid with the bowl feeder. This was just because the vibration was too high at the end of the ramp. We also painted the ramp black and added a small amount of non-reflecting fabric, so the contrast between anchor and the ramp would be high as possible because anchors reflect light very well.
As a cobot, we used Doosan A0509S for our project. We designed our pneumatic end-of-arm-tool (EoAT) gripper for picking and placing anchors and pins into a rotary tray of the assembly machine. Anchors are picked up from the end of the ramp.
During the final days of the project, we had to re-design EoAT and modify the ramp because anchor must be taken out in three different ways depending on orientation of flat side of the middle point of anchor. Parts for the EoAT were 3D-printed from PLA plastic.
Modification for the assembly machine had also been done to reach rotary tray. We removed its light curtains, so the rotary tray is reachable by the cobot. This safety device is not needed in a cell where are no people working. We also connected tray rotation signal wire to robot controller I/O-ports so it can be operated from the robot program.
Project Result
Building a robot cell was not the most challenging phase of this project. We used a lot of existing materials from the company, for example tables, platforms, machines and so on. Integrating vision and a robot code took a big slice of our time in this project, not forgetting testing which also drained the time a lot.
After all we were able to pick a pin from the tray and put it to the assembly machine, and after that detect orientation of anchor and put it on a pin in assembly machine and finally make a complete product.
Epilogue
With the time we had we managed to make a working robot cell with a working solution we managed to do it. Of course, we did not do this all alone. We received a lot of help from the company, for example finding the right tools, parts for our project and welding parts together.
We want to thank our steering group from SILICON B.V., Koen Van Mil and Danielle Garot for coordinating and helping us when it was necessary. Big warm thanks for an awesome group of SILICON B.V. employees who helped us during the journey.
We also want to thank our teachers, Thijs Brilleman, Mathijs van der Vegt and Guus Paris for helping us to push forward during the project.