hi friends, i have a problem in offline programming as i am downloading the robotstudio program into teach pendant the robot is not going at perfect position, can we calibrate this offset? if yes what is procedure for calibration that total program will take the shift
offline programming
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Tushar_Patil -
October 13, 2014 at 5:10 AM -
Thread is marked as Resolved.
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I am unsure of abb, but IGM and motoman's you pull the robots parameter files and put those into the offline programs,,, that usually gets us most of the way there (did you do that?) How far off are the points and positions?
Which programs are you using? (and version)? -
probably your base frame information is not correct in robotstudio. Right click on your system controller and then click edit system and come to robot base frame. There is a options on the page which name is "use current station values" then click ok and restart the system
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what will happened after doing that, can you please let me know.
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Robots are not precise. The have a good repeatability.
I mean that the best you will get in terms of precision is 0.3mm after a big effort in calibrating the robot.
If you look at the absolute accuracy information sheets you will see the manufacturer usually says that the precision will be of +-1mm.
Once this has been said and knowing that you won't get a better result, you should java a well parameterized tool and base.
Hope this helps.
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probably your base frame information is not correct in robotstudio. Right click on your system controller and then click edit system and come to robot base frame. There is a options on the page which name is "use current station values" then click ok and restart the systemcareful, you probably don't want to be changing the robot base frame if just the program is off as potentially it is just the work object that is not calibrated correctly.
If you change values in your work object you can use the data to shift your whole program - but what Joan Murt said is correct in that you may not ever achieve the offline to online accuracy you want without touching up programs
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Everything is possible, it all depends on where you want to spend your time... touchup or calibration.
If you don't have ABSACC, the installation is bad, fixtures are horrible, you don't care to use work objects or a good TCP (yes, I've had customers tell me they don't need a good TCP as they have smartac / search and weldguide) - then yes, I'd be surprised if you see better accuracy than 25mm / 1".
But if you address all those issues you should be much, much closer than that.
As far as AbsAcc goes - keep in mind that it doesn't change repeatability, it does what it says... it improves the absolute accuracy, so if you tell it to go 1000mm it'll go 1000mm v.s. a non absacc unit that might go 999mm.
This is obviously important for offline since a 3D model in RobotStudio is mechanically 100% perfect, no tolerances, no play, no backlash in gears, no mechanical deflection due to payload, etc... Perfect !
Reality - not so much.... Still frekkin awesome considering the complexity of a robot - just not perfect.So - you have to calibrate the cell...
Depending on the layout you'd have to do a "general" calibration of the robot, positioner, tables, etc. to adjust the position of all the equipment / baseframes etc. next step is to utilize work objects wherever you can - benefit of Rapid is that you can have as many as you like, so you can calibrate each "area" you operate in.To Joan Morts point, 0.3 is "good" and should be acceptable for most applications - if it isn't, then odds are you have just as much or more variances in your parts and need vision / seam trackers or something to help the robot guide itself.