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Pembuk

Specific cam instruction - Kinetix6000

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Hi all, I would like to ask you for some ideas how can I solve my problem. I need to build the system, which will switch on digital output when my moter will be in specific positions. I drew a simply chart for better explenation. At this moment to do that I use compare block to watch motor command position and then set the output. But for some reasons it's not working correctly. The output is not set allways at the same position. Is there any other option to make it better? I know cam profile blocks but they can only be use to synchronize two drives not to set outputs.

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I would try using the motor's actual position. There could be timing differences between the motion planner and the real-world position. If you use the motor actual position and your compare statements, then you should see much better results.

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Yes absolutely, use the motor feedback position, not the command position. Also, your compare instruction might need to be in a scheduled task with very short period (< 5mS possibly?), depending on how fast your motor turns. Otherwise the motor position could just jump past your setpoints between scans and the compare instruction won't be triggered. Ideally, you could use a limit instruction, so that whenever the motor is within a specific "zone" the output turns on, instead of at specific "points" as per your diagram. This would help prevent missed scans. Also make sure that the actual physical output tag (or alias) is in the same high speed task. If the output goes to a mapping tag, and then gets mapped to the actual output in a seperate routine (common practice), this could also cause timing problems for high speed applications. Edited by MrAutomation

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@pembuk The instruction you're looking for is MAOC (motion axis output cam). It will compensate for axis speed and reaction time of whatever you're operating with the cam output.

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Thanks for this tips. At the beginning I used axis actual position (it's logical to use this variable), but because of many shifted output points signal I tried to use command position with better results. I've seen this tip on other machine. But unfortunately I still see moved output signal. To be honest to trigger output I use one compare block to set an output and reset after specified time (100ms). This application is used to generate trigger signal for inkjet printer, which printing head is moving on traverse, perpendicularly and above the product rows. The printing moves about 1m/s. I need to print a code which has about 25mm on 30mm lenght area. So when my trigger will be generated just little late I loose a part of code because it's printed outside the product. As you said MrAutomation I need to put this logic to high speed task. How do you think, will MAOC instruction be useful in that task? I've never used it before.

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Sorry Gerry, I started my post before I recieved your reply. I'll try MAOC

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