Graco Flex Feeder

matthewd92

Anyone using the Graco flex feeder?  We are looking at using this for one of our customers due to the flexibility of being able to redeploy it easily versus purchasing a hard tooled vibratory bowl feeder but would like to speak to someone that has used them.  Are there other brands that we should be looking at instead?  The current part we are feeding is roughly 3" long and about 1/2" OD but its cam shaped.  We plan to use the vision from the feeder to also locate a feature on the part once we pick it so that we know precisely how to place it onto the fixture the part is being loaded onto.

jhart

@matthewd92

As you can see in the video that @Samuel_Bouchard posted above we have a demo set up to locate and inspect poker chips as they come out of the Graco feeder.  We mounted a Cognex camera to the flex feeder in order to find the location of the parts and to do the inspection.  The inspection was simple enough that we were able to do that and locate the part with the same camera.  When the camera is triggered and doesn't find any parts in the tray it signals the feeder to vibrate and add more chips to the bowl on the front.  The camera sends the information into the Mitsubishi robot that we have picking up the chips.  It sends the location of the parts and where the chips should be placed. 

We've used the same feeder with very few adjustments to feed different parts.  At one point we had thin plastic dividers being fed into the bowl with almost the same exact setup as we have for the poker chips.  The adjustments that we made were to the frequency of the vibration.  This is easily done on the bottom of the feeder.  There are buttons that you can adjust multiple settings on.  

Hope this helps. 

Alexandre_Pare

@matthewd92
That's funny. I was just looking at this system this morning and referred their video to a client. I did work on some vibration feeder in the past were we actually designed the entire system. So basically buying a vibration motor on Mcmaster Carr and designing the whole thing. Turns out that we spent quite a lot of time just figuring out the proper vibration parameters, weight balance and feeder design to make good part separation on the table. I took a look at the Graco G-FLEX manual and you have a lot of parameters to play with. Which is good because you need this to adjust to the different parts that you want to process. I have not worked with this systems but it looks good based on what I am expecting from such a system. It would be a great combination with UR and Robotiq camera! If someone is able to try it out it would be nice to have feedback and videos here!

matthewd92

@Alexandre_Pare  We are trying to get some references out of Graco and its been like pulling teeth. Unfortunately for us, we don't have the process time to use the wrist camera, I need the robot to already know where its going when it goes to pick the part and to know that there are parts there to pick.  We will be running the camera and feeder in a separate thread so that we always know we have parts.  Also, we need a camera for finding a feature on the end of the part, we will hold it up in the camera field of view and take a second picture of the end.  Early in my career I can remember when the maintenance team designed a vibratory transfer line, this was huge, the bed was 8' wide and 20+ feet long, it was used for transferring castings off the end of the mold line to the grinders.  Took quite a while to get the vibration right on that one, like 3 months.  I'm not sure I am brave enough to tackle that again.

Samuel_Bouchard

@jhart I see in the video below that you use the Graco feeders at Proud? Can you share some insights here?

Alexandre_Pare

@jhart,
really nice. thanks for the feedback. Do you have ballpark USD figures for this Graco System? It can take away most of the pain of adjusting such a system if someone tries to build it from scratch!

matthewd92

@Alexandre_Pare we are placing an order for one on monday. Price with vision was in the $24k range so about the same as a vibratory bowl feeder without vision by this is flexible which will fit our business model better. We are currently looking at 5-6 applications with customers that will use this same feeder. One of the robotic workers will actually do two different jobs but use 1 feeder

Sebastien

@matthewd92
I was curious if you ended playing with the Graco system. Any comments, feedback or videos?

matthewd92

@Sebastien we are in the middle of deploying it right now. So far it works pretty well. Feeds parts very quickly, is pretty easy to adjust and then control from the robot. We have the feeder and camera being ran in a thread so that the table can move parts around while the robot is working. 

When we have some some decent video I'll upload some. Initial impressions after playing with it for about a week and a half is it's. nice unit, well built and does the job we need. 

Sebastien

@matthewd92
So camera sitting on top of the feeder, are you using Robotiq's camera?

matthewd92

No we aren't, we need to process images in the background for quick picking.  The target pick to pick cycle time is around 3 seconds.

We are using 2 SICK PIM60 cameras.  One mounted to look at the table for part location on the vibratory table, the second is locating a feature on the part that we have to place onto a pin.  There is a hole in the part but its not down the center, there are 8 possible locations based on part orientation, then throw in there variability from the gripper and there are a lot of different places that the hole can be.  This approach allows us to get offsets for the part to be placed on a "fixed" location pin.

lakshmip001

Can I use Robotiq camera with Asycube Series - Flexible 3-Axis Vibration Feeders? I worked with Robotiq Vision Camera, it can detect only one part  which matches maximum, at a time at snapshot position. Then amount of time it takes will be more as it needs to be detecting each and every time. Can I make the process fast?

matthewd92

@lakshmip001 if you do not have any large demands on a quick cycle time I don't see why you couldn't.  However, you will not be able to control the feeder from the background.  I think you would have to wait until you just can't find anything to pick then turn on the feeder to try to find something.  After so many parts picked you will need to turn on a hopper if you're using one to refill the parts on the table.  

This is how we are doing it currently.  In a background thread we are looping through looking for a part on the table. The loop is check to see if there is an acceptable part, if not, turn on the table for 200 milliseconds, turn it off and wait 500 milliseconds and check again, repeat until we find a part, if we can't find a part after a certain number of cycles we will turn on the hopper and dump more parts.  We then go through the loop process again.  After 15 parts are picked off the table, we turn on the hopper and attempt to dump more parts.  The reason I say attempt is sometimes there is a "log jam" of parts in the hopper. We will be changing the camera code in about two weeks to also return the number of parts it can find in the image.  If the number of parts drops below a threshold then we will turn on the hopper to get more parts.  This should allow us to compensate for the log jams we are seeing.  I cannot imagine trying to run this vibratory feeder with a robot mounted camera and achieve any quick cycle times.  Even currently, we will have times where we are waiting for 10-20 seconds for an acceptable part to be presented to the system which is why we are making some code changes to try to speed up that process.

lakshmip001

matthewd92 So, It means I can use Asrily feeder with the Robotiq Wrist Camera. But Asrily feeder vibration can only be obtained when object is not detected and the other features of Camera cannot be controlled. And as the Robotiq camera takes minimum 10-20 secs to detect an object process is slow. And Robotiq camera can detect only one object per cycle.

 As shown in the video can Robot pick randomly placed screws on the flat surface??
So, UR camera can work this feeder. Am I right with the conclusion.

Thanking you in advance.

matthewd92

@lakshmip001 Theres no reason that the camera wouldn't work.  The camera will find an object on the feeder just like it would on any surface and then send the coordinates to the robot to pick the object.

Tyler_Berryman

@lakshmip001 Yes, you can use the Robotiq Wrist Camera with this type of feeder. The difference between using the wrist camera and a fixed camera is that timing of your program.

If you are using a camera that is externally mounted on a rigid fixture, the camera will be able to locate parts while the robot is moving around. That means that when a part is located, you can send the coordinates of the part to the robot so the robot can then go and pick it up as soon as it is done it's previous task.

If you are using a wrist-mounted camera, the robot will have to go to a snapshot position in order to find a part on the feeder. This will add a bit of processing time since the robot cannot complete a task while the vision system is locating a part. However, there are advantages in using a wrist-mounted camera in this type of application:

1. You will not have to design the external mounting for the camera since the wrist camera is mounted directly onto the robot's wrist. 
2. The wrist-mounted camera is not sensitive to the vibrations of the table, whereas the externally mounted camera could be sensitive to vibrations or movements created by the feeder or someone knocking into it.

Though the Robotiq Wrist Camera may have a longer acquisition time than externally mounted camera, I have never seen the acquisition time go up to 10-20 seconds. I would say that the longest acquisition times that I have seen is 4-5 seconds to locate a part.

mertzga

What is the largest part dimensions the Graco feeder can process?

matthewd92

mertzga said:

What is the largest part dimensions the Graco feeder can process?

From their specifications the largest part is a 3"x3"x1.5" with a maximum of 30 pounds on the table

Asyril

For those looking for Flex Feeders compatible with larger & heavier parts such as those you described Matt: Asyril is preparing to release a new, larger feeder in June 2017 - using the same 3-axis vibration technology known from our smaller vibrating platforms. Feel free to contact me for more info...

The following link shows an integration example showing the Asycube 240 platform featuring a Universal Robot and a wrist-mounted camera similar to Robotiq's:

https://www.youtube.com/watch?v=yetFv3f1wTE