kuka krc2 - laser cutting

For laser cutting you need a laser cutter . A robot is not enough.

If you attach a laser cutter to the above mentioned robots, why shouldn't they be able to do laser cutting.

But the precision may be a problem. Depends on your needs.

Quote from hermann

For laser cutting you need a laser cutter . A robot is not enough.

If you attach a laser cutter to the above mentioned robots, why shouldn't they be able to do laser cutting.

But the precision may be a problem. Depends on your needs.

Thanks for reply.

i know .laser cutter attached to our robot.

Does the robot(krc2) respond in terms of accuracy?

Quote from mehrandinio

Does the robot(krc2) respond in terms of accuracy?

You didn't quantify your needs for accuracy.

Same for the next, question about the 5mm hole.

I want to make a lot of holes with a diameter of 5 mm by laser cutting. Is this type of robot(krc2) accurate or not?

Try to answer the questions asked by those trying to help you.

What accuracy are you looking for? Is it +/- 0.01 mm or +/- 2 mm?

When you says: this type of robot(krc2), which one? KRC2 is controller. You mentioned two sizes in the first post, they may have different accuracies.

Did you look into the documentation of the robot you are looking for? They have their accuracy specified for each type/size of robot. The robot also has different path accuracy, depended on the speed.

as everyone already shared - you need to specify what is it exactly that you need... that means put some NUMBERS in your requirements. suppose you are ok with 0.1mm... but what does that mean?

are you cutting material that is paper thin or 30mm thick? is this 0.1mm tolerance only important on top side or at the bottom as well?

how about grouping - do you expect to cut the 5mm hole in one and the same place or bunch of places that are far from each other? standard robot can get you good results in the 5mm holes are grouped in 200x200mm area. but if you want to do the work on product that is 2000x2000mm that is not going to work unless you spend a lot of time manually adjusting location of each hole every time new pattern is introduced...

if you just want to get the KRL program exported from some CAD software and run it immediately with little or no setup and the area you are working with is large, you will need HA or ABS robot.

STD = Standard robot. that is 99% of the robots coming of assembly line. They are ... average... but ok for vast majority of applications. They are all assembled from parts that meet certain acceptable tolerances.

ABS = absolute accuracy robot. like STD but uses additional data set to make corrections. requires robot arm to be specially measured - this increases time and effort to produce robot and of course costs more. can be done in factory but also on-site. commonly done to increase accuracy of standard robot. the correction can be switched off.

HA = High Accuracy. like ABS but also the robot arm is made from handpicked parts with particularly tight tolerances. Only possible in factory and only done upon special order. This is grade above ABS and of course costs even more. After all people on production line inspecting and measuring each produced part need to be aware that there is need for specially good parts. It takes some time and volume of parts to be produced until the perfect ones are encountered and set aside.

every robot i ever saw used for applications with laser or water jet were always HA or ABS variant and... new. robots that have years of service have some wear and tear, increase in backlash etc. and gradually this affects accuracy more and more. i have not seen anyone planning application like laser cutting to select STD robot. and that on top of that also choose one that is 15-20 year old. it sure can work but the whole point of making something accurate is to optimize everything for accuracy.

get your robot measured. you want it to be ABS...

Only when the robot is fitted with the laser cutting system ...

Robot is just a delivery system, cutting is done by laser alone. You can mount laser on a farm animal and it too will be able to laser cut...

Quote from m.dinio

For the general conclusion, can the robot(kr210 with Positioning repeatability* ±0.06 mm or kr200 l140 comp) perform laser cutting (not very accurately) or not?

It depends on how you define "accuracy". Also, is your specified 0.5mm repeatability for the radius or diameter of the circle?

If the circle is hand-programmed, and tweaked properly by running test cuts, then yes, you should achieve your target 0.5mm repeatability, in the robot. Cut kerf could still vary due to differences in the metal, air blast, laser power, etc.

However, if you want to simply mathematically program a 5mm circle (+/-0.5mm), you will get an oval, not a circle. This is because robots, while repeatable, are not accurate -- a robot with 0.6mm repeatability will probably have an accuracy that's roughly 10x that value. And cutting a circle is one of the worst case scenarios -- it forces multiple axes to reverse direction multiple times during the cut, bringing all the "lost motion" (basically, backlash) into the entire cut.

Cutting while changing the TCP orientation (say, a "conical" cut) would be even worse.

ABS tuning can help, to a limited degree, but is not a panacea. For one thing, an ABS tuning of the robot's entire work envelope will average out error over a large volume. And changing the tool payload will also throw the ABS tuning off. Getting maximum benefit from ABS tuning requires doing the tuning in a small volume, while carrying the working payload. And even then, in my experience, it only gains maybe 10-20% accuracy.

It might be worth pricing a SARCA module, and tuning, from New River Kinematics -- it works better than ABS (in my opinion), and might be price-competitive.

Quote from SkyeFire

For one thing, an ABS tuning of the robot's entire work envelope will average out error over a large volume.

Yes but one can choose how to cluster points.... spread them or group them in one area. Then corrections will be good there but not so good elsewhere. This is why knowing the work area before measurement is important.

i have not done any evaluation but reason for ABS is to correct for mismatch between actual robot links and robot model.

one can tell STD robot to move from point A exactly 1000mm in some direction and robot will move but upon arrival it may be couple of mm out. This is not a problem if points are manually taught since programmer brings robot to each point before touching up. But this is a problem if the position data was exported from some CAD file. And that is where ABS and HA robots come in.

so if all of those 5mm holes are on a dinner plate sized object - no problem, stick with STD robot. but if the object is size of house door, that is not going to be good unless you teach the points manually. and you have hundreds of them and they change frequently it is easy to see why this may not be practical.

also contact your laser equipment manufacturer and have a chat. they will know what to recommend.