Why TouchSense doesn't work correctly?

  • Hi, guys!!!
    These day I faced an issue of bad work KUKA.TouchSense technology package. May be something wrong with my programminge skills or maybe something wrong with the KUKA add-on technology package, I don't know. But it works not quite correctly. When I make workpiece offset TouchSense software corrects originally programmed path, but it does it not so good. What I mean? You can see result on a video.


    1. No workpiece offset, originally programmed path, touchsense is off:



    https://youtu.be/_odsvqn_GYk


    2. No workpiece offset, touchsens is off:



    https://youtu.be/n39uYbiUvVk


    3. 2D offset, touchsens is on:



    https://youtu.be/xseWp6GtDEo


    4. 3D offset, touchsens is on:



    https://youtu.be/EgXq1_-fgMI


    Can somebody explain, what's wrong with performing of TouchSense?

    Edited once, last by lomaxe ().

  • AD
  • - Is it tool, base and robot calibration correct?
    - Which sensor do you using for touch sense?
    - Is it sensor directly connected fast measurement input?
    - Is it robot base parallel to ground or do you correctly teach a base frame?



    Normally laser sensor is not recommended for touch sense. Because sensor signal is delayed. You can use torch body and ground short circuit for touch sense. Please review touch sense manual for circuit.



  • Quote

    - Is it tool, base and robot calibration correct?


    Yes


    Quote

    - Which sensor do you using for touch sense?


    Keyence IL300


    Quote

    - Is it sensor directly connected fast measurement input?


    No


    Quote

    - Is it robot base parallel to ground or do you correctly teach a base frame?


    Yes


    About fast input and usual input. We tried an experiment to understand weather there is a big difference between fast inputs and usual inputs when robot gets a point using keyence. Here are results:


    Fast input:
    DECL E6POS t1={X 1698.52307,Y -46.8219719,Z 1389.56323,A -176.999680,B 53.7516441,C 177.722382,S 'B0110',T 'B00110010'}
    DECL E6POS t2={X 1655.48047,Y -61.4947128,Z 1389.61084,A -176.997833,B 53.7562141,C 177.724472,S 'B0110',T 'B00110010'}
    DECL E6POS t3={X 1654.00989,Y -32.6900673,Z 1389.60657,A -176.996384,B 53.7575188,C 177.727478,S 'B0110',T 'B00110010'}
    DECL E6POS t4={X 1698.52429,Y -46.8197403,Z 1389.56519,A -176.999496,B 53.7520447,C 177.721832,S 'B0110',T 'B00110010'}
    DECL E6POS t5={X 1655.48,Y -61.4957809,Z 1389.61023,A -176.996460,B 53.7561,C 177.725815,S 'B0110',T 'B00110010'}
    DECL E6POS t6={X 1654.01,Y -32.6890373,Z 1389.60645,A -176.996964,B 53.7575226,C 177.726883,S 'B0110',T 'B00110010'}



    Beckoff input:
    DECL E6POS t1={X 1699.04883,Y -46.8205185,Z 1389.55249,A -176.999008,B 53.7515793,C 177.722427,S 'B0110',T 'B00110010'}
    DECL E6POS t2={X 1655.38684,Y -61.7026863,Z 1389.60645,A -176.997467,B 53.7558327,C 177.725281,S 'B0110',T 'B00110010'}
    DECL E6POS t3={X 1653.91150,Y -32.4768715,Z 1389.60303,A -176.994675,B 53.7572632,C 177.729309,S 'B0110',T 'B00110010'}
    DECL E6POS t4={X 1699.03796,Y -46.8201408,Z 1389.55737,A -177.001190,B 53.7522545,C 177.720795,S 'B0110',T 'B00110010'}
    DECL E6POS t5={X 1655.37769,Y -61.7229195,Z 1389.60596,A -176.996490,B 53.7557716,C 177.726166,S 'B0110',T 'B00110010'}
    DECL E6POS t6={X 1653.91809,Y -32.4911270,Z 1389.60278,A -176.994751,B 53.7572098,C 177.729187,S 'B0110',T 'B00110010'}


    So we decided to connect a sensor to usual inputs...

  • Touch sense does not use or change to position data. It's work based "function generator". This mean if you want to effective cycle you must be connect touch sense input to fast measurement input. Position data not effective. Touch sense calculated value for function generator, not for position. Beckhoff KL or EL input modules have 3ms reaction time but KUKA controller have 12ms for interpolation cycle. This mean sensor signal delayed minimum 12 ms or 12+3ms. We use fast measurement inputs for it. And also laser sensor have internal delay for produce output signal. It should be mechanic touch just like torch body and ground connection.

    Edited once, last by M.Ozkan ().

  • Today I used fast measurment inputs for TouchSense. The result is the same, even a bit worse. :help:


    I used such a type of welding power source like that's on video. It's connected to the conroller through deviceNet or profinet or ethernet... The signal about touch by the wire tip is being transmited through the power source to controller, so, it doesn't use fast measurment inputs(((

  • Quote

    I used such a type of welding power source like that's on video. It's connected to the conroller through deviceNet or profinet or ethernet... The signal about touch by the wire tip is being transmited through the power source to controller, so, it doesn't use fast measurment inputs(((


    Yes Fronius can be send with field bus and also have optional touch sense interface. With touch sense interface, Signal activated directly from torch and going to Fast measurement input on RDW. There is no delay. We are already use it with touch sense.


    Based on my experience:


    - You should connect fast input.
    - You should use mechanic touch.


    After then you can check touch sense, tool and base settings, and do not forget calibrate (Set New Reference) touch sense. You can read manual for calibration procedure.

    Edited once, last by M.Ozkan ().

  • fast measure input is ... fast (125us=0.125ms).



    that is on the order of some 100x faster than standard input.



    so to get comparable result using standard input, you would need to slow down touch sensing motions 100x.

    1) read pinned topic: READ FIRST...

    2) if you have an issue with robot, post question in the correct forum section... do NOT contact me directly

    3) read 1 and 2

  • I'm sorry, i fit.
    But the speed of measuring the sensor 0.05 m/min, or 0.83 mm/s. When the response from the fastest input is 125 microseconds and the sensor's response 0.33 milliseconds, the robot will go little, but with a response of 100 times more (12ms), he will pass as little as 10 microns, and a mistake touchsens up to 10 millimeters in one of the planes, and in others it may not even be.

  • I don't have an oportunity to use fast measrment inputs and a mechanical unit for measuring but these days I performed some experiments with searching and positioning of the workpiece (I used usual inputs and laser sensor) and I noticed, that correction is good when position offset of the workpiece is small. I had good performence when position offset was along the length, width or height. Bad performence when the workpiece was tilted along the length and width. The more the workpiece was tilted, the worse correction performence was. At small tilting along the length or width the correction was very good. But when tilting was big enough, there was a correction (it was seen) but TCP (wire tip) wandered from path (as it seen on the videos).

  • I don't have experience with TouchSence it self, but i know something about search and stuff.
    It look like on the video with 3D search you didn't tilted the part but you twisted it. And as i say I don't know a TouchSense, however I think it won't work in that case. it's basic adjusting the base not the path it self so you can tilt it in two or more directions but it must be in the same plane as before . Graphic way to show what i say: From "_ " you can do" \ "or" / "but not" ~ " And second of all i think that you should have a tool defined on the point where the laser sensor is turning on ,this is why other guys told you to use the tip of the wire, or try to keep perfectly the same orientation (A,B,C) in all measurement points.

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