Posts by Affaltar

I don't know answer to your exact question, but you should be able to see all changes in logbook.ls file from the backup, with timestamp

I got another problem, I can't compare this with IF because when I try to enter this code manualy to register or as constant it changes it, probably because of some rounding. All 3 SRVO alarms become 906690560, and INTP_254 changes to 101449982.

If I leave it like that IF function returns false. I tried to calculate mod 1000 and compare with just last 3 numbers and that works, but I don't know all codes, I don't know if I'll get false alarms with using just last few digits

So while this "hack" will work and output a last alarm, with probably significnt enough number of digits, I don't know the mapping of it to any real alarms and I'll have to write it manually every time new alarm occurs, so if anyone has a better solution please save me from this

I found in appendix A of Handling tool manual the explanation how error codes should be assembled, but I can't read it from $ALM_IF

Alarms I could get easily and the codes in $LAST_ERCODE

SRVO_001 - 906690561
SRVO_002 - 906690562
SRVO_003 - 906690563

INTP_254 - 101449982

Is there a list with this encoding of the alarms? So if I know some alarm code I can know the number without reading it there?

Hi, I need to send alarms from robot to plc via modbus. I can't buy more options.
I got to read $ALM_IF.$LAST_ERCODE and I get unique codes for each alarm in my register. Is there a table to know which error it is? I would like to map some expected errors to simple variables and send anything else as "other error" so our monitoring from PLC can know what's happening.

If there's a better option to use over modbus I'd love to hear that too. I don't have karel or error code output (or probably any other paid option)

Hi everyone!

Is there a way to measure and dinamically set forces used in Touch Skip?

I would like to have a very light touch with my robot so I'd need to measure the forces in last part of free movement and press untill it's about 5-10% more.

Depending on the position on the table the forces vary a lot and I can't set it up precise enough manually, it either stops sometimes without touching anything or pushes too hard.

If it can be done without paying extra that would be the best

Thank you all so much for the answers.

Quote from mortoch

As far as polishing/grinding wheel wear we shoot a laser across the leading edge of the wheel and computer in the PLC how much to adjust based on that feedback. Adjustment is done with a gearmotor and worm drive typically. Wheel is also mounted on a cushion to allow for part abnormalities with a sensor to determine that cushion has not stuck causing over adjustment.

How often do you adjust the edge? Is it more practical than just measuring force?

Quote from Devendra.r.jain

i will recommend to use pneumatic float for your grinder as maintaining force. Rest things depends on you requirement of final finish.

Pneumatic float that I get from google doesn't seem like something I could use for that, it's either a level sensor or a water vehicle, do you have some links or better keywords to find what you're talking about

Quote from SkyeFire

PushCorp is a company I've worked with before, that has a variety of robot tools in this category.

This unit: https://pushcorp.com/product/stc1503-bt30/ has a tool-change that can be automated.

This unit: https://pushcorp.com/product/afd310/ can be used as a mounting for the spindle unit, and can be commanded to apply a constant force.

Not cheap, but I've had good luck with their gear in the past.

I'll compare the mounting with the fanuc option for price and simplicity of use, but the spindle looks exactly like what I need. Only problem might be distance, there are no suppliers in my part of Europe, but probably someone will ship it to me.

Hello everyone,

I got a new project to grind and polish large stainless steel pieces with a robot, few different models, and I have no idea where to start with the gear and options I need so I could use your recomendations

There are three types of pieces, flat circle with a weld that has to be removed, cone with the tip missing and dome. Cone and dome have to be polished on the inside

I need to go over the whole part with 5 different grits of the wheel, what is a recommended way to do that? Is it possible to just change wheels automatically with robot or should I get also 5 grinders? Recommendations for tool changing systems for that purpose?

Force has to be regulated, path will be the same for each piece in series, but offset will depend on the wear of the grinding wheel, is just an option for Fanuc enough or should I get some compliance device?

Ideally each piece would be placed on their table and then moved to the robot for the work, but they need to rotate, so I'd need at least two rotational units, one for the dome and one for the cone. Dome can be on a simple rotational positioner and I can probably change directions between passes, or just move it back, but the cone is a bit trickier since it should sit on wheels and I don't know how to exactly regulate the position.

Can I just switch the rotators on the go and have each one on it's table that will be wheeled to the cell?

Any recommendations for vacuums to mount on the robot?

Sorry for the huge amount of questions but I'm new at this and when I try to search for anything I just get adds from supliers. Thank you for reading

Quote from the leg

The lose of mastering on power down will be the RDW has come to the end of its like for storing data . Replace the board and the problem is solved. Else just drive to the zero position before powering off. Then on power up dial master

I know what needs to be replaced, but that's 1500+ € part to replace, and it's on the bigger robot. I'm more curious about switching all the other parts from the big one to the small one. I have very little experience with kuka and with old robots in general, I just want a toy to play with, and I'm getting it for the price of iron of that weight.

If that will be the only thing needed in the end to make the robot completely operational I could maybe fix it if I find a buyer, but I don't even know what would be an ok price for that kind of robot?

And thank you very much for the dial master tip, I could do that if I end up using robot as it is.

I am buying a very old KR6/2 (somewhere around 2003?) that should go to scrap metal, I'll find some space in garage and place it there, try to turn it on eventually. It hasn't been used in years, but I'm told it was giving some power errors/warnings before it was decomissioned and put in the storage. It has about 9000 working hours.

I would like to turn it on and use it as a kuka robot, but if that doesn't work I'd be happy with just using the mechanical unit and make some sort of my own controller. Does anyone have any experience doing that? What hardware problem might make it completely unusable?

I might also be able to get a KR16 from about the same time, which generally works, but doesn't keep the motor data and needs to be mastered every time. Would it be useful to get it for spare parts for the smaller one? Smaller one seems much more practical to keep in a small garage, I would consider selling the rest of the big one after I get the small one to work.

What would be ok price to sell that kind of robot for?

Thanks all for the answers, they're very useful in general, but mainly missing the point, most likely because I didn't ask the question well enough.

I understand the principles and ways of getting the times, the analysis was the problem

I quoted just parts to reduce the length of the post, but reply is to more than

Quote from massula

With this data, I go to spreadsheets and make my basic number crunching.

This part, how to do this, I can do it just by laying out parts and their times and then manualy putting them in different orders, trying to calculate what the end time will be. I was hoping there's a nicer streamlined way to do it.

The robot is Fanuc, I can measure time with it. And that last part is what I want to learn to do, find what is worth optimizing, where I can add new actions without affecting time and getting the best solution. Without doing it again at the machine and seeing how long it takes

Quote from HawkME

I have always used excel for things like that (cycle time analysis).

This helps a lot, I now know the exact term to search for and I see I can get some useful papers about it

Quote from panic mode

once you have all the values, throw them into Excel and summ them up in different ways to see what you get. this is all about finding efficiency and maximizing output (time is money) and everyone likes options and comparisons over being cornered with one and only possible setup.

As I mentioned, this is what I don't know how to do well

About unloading, I do it in same step as loading, I have two grippers and just swap the parts while inside the machine, that's why I didn't mention it seperately. But for example in one process that swap lasts 6sec because the machine has to unclamp the part while robot holds it, and on other one it is 0.3 sec because there are two positions ready and the grippers are positioned in a way to hold both at the same time.

And I know clearly that I could get some time from reducing those 6sec, but if I reduce it to less than 2 it won't matter anymore since the robot will have to wait for the other machine. And I don't know a good process to do all those calculations properly

Quote from SkyeFire

If the CNC machines' cycle times were deterministic, you might be able to stagger them such that there is never a time when any CNC is waiting for the robot, assuming that the robot cycle time for any CNC machine is less than the serialized cycle times of the other two CNCs. But that kind of setup is delicate and usually unnecessarily complex and failure prone. And if your CNC cycle times aren't deterministic (say, when you change over from a 5min part to a 6min part), well... at the end, it's almost certain to be more work than it's worth.

I don't really understand this

Yeah, I know the solution, that's not the problem (But still thank you very much for the answer)

I would just like to know a way to design/test it, there will be more complex problems where orders will matter, way to find out if a second on one process will change anything and things like that. And of course to have a nice way to show my boss both versions and calculated times.

Hello everyone.

How to do timing analysis? I have no idea where to start so I'd love to get some useful material recomendations to study about it, or the way you do it.

I currently have a robot tending 3 milling machines and robot goes from the loading station to each machine one at a time. At one point all the machines are full, robot waits a bit and then fills all three machines in a row with no pause in between. My boss asked how would it affect time if I forced a robot to wait for each machine a bit, stagger them in a way that robot splits his bigger wait into 3 smaller ones.

I could make a table in excel and try to set up some timing diagram and try to move stuff manually around to see what would happen in theory, but I'm sure there's a better way, I just don't know it yet.

Doesn't 3d vision have an option to limit that angle automatically? So you don't do calculations yourself? 2d vision from fanuc does.

There's an option MROT which should do what you want, it should be free, but needs to be activated, at least that's what Fanuc told me, in the mean time I solved the problem otherwise

From my experience Fanuc doesn't lose any data from full shutdown, why is that a problem?

Quote from Runis86

But that would still require one register for each program. If I have 100 programs that would require 100 R[n] to store the timer value.

I imagine it like this.

Start of program would have

TIMER[1]=START

End of program would have

TIMER[1]=STOP

R[n]=TIMER[1]

TIMER[1]=RESET

Display More

Oh, sorry, I missunderstood you then.
In general way local varables wouldn't work as they would dissapear after the program ends. You can extend your registers to have 999 of them, then you would have enough

You're missunderstanding me, I didn't explain it well enough

"n" is always the same
for example in every progam have R[5] = something

First program would have R[5] = 123.456
in second you have R[5] = 543.345

You wouldn't have unique registers, just one register and hardcoded local "variables". They'd actually be constants, but if I understand you correctly that's what you need?

You of course have to be careful not to start a program from middle without setting those variables.

Hardcode them in the beginning of the program?

Make some numeric register that you'll use for that variable, and make one of the first lines in your program.

R[n] = 123.456

This is what I do for a table of variables, I have 10 programs, but about 20 variables that need to be changed depending on which it is

So you have no knowledge of how to do something and you want to sell a claim that you know how to do it?

Your budget is approximate price of 3d vision system for Fanuc (I don't have quote, just a Fanuc representative mentioned it in passing, it might be off), which is made to pick one kind of part from a box. Not including the robot, or anything else.

My suggestion would be use some kind of shaker feeder to get one from the box, use a conveyor belt to move it to checking area, process it by camera and make some simple pneumatic sorting station with 2-3 lanes that you could make the sort easy. That should be well within budget. For final solution you need a very good scaning station that can recognize hundreds of different types and if they're in good condition, and you can either make a sorter yourself or just use a robot to drop it in a box, but I would avoid bin picking and just use some feeding mechanism to get to the station

You have total of 4000 items? In the lifetime of project? Get some cheap labour to do it, but it would probably be faster to just do it yourself instead of teaching someone distinction between each type and definition of good and bad.

Otherwise, you need to know how often do you get a batch of 4000 items, should you sort 4000 a day, a month, a minute? Depending on that you can see what to do. If there's no time limit you can just feed one by one item in some scaning station, make a scan, 3d laser scan or pictures or whatever you like, and dump it out to propper place. But you need much more details of limits, budget etc...

What are you doing this for? Are you willing to hire someone to solve the problem for you? Or are you just having fun?

At least you didn't drop a 290M $ satelite