Soft Limit issue with 5-Axis Positioning

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Soft Limit issue with 5-Axis Positioning

Post by MattBlight » Fri Nov 20, 2020 11:56 am

G'day Tom,

I am often running into an issue where i'm having to disable my soft limits when attempting machining operations in 5 axes near the limits of my machining envelope. The issue seems to be that the soft limits are being checked based on the TCP position, rather than the actual axis position.
I'm seeing it most when for example i'm using a long'ish tool which would not be able to reach the top of the part if it was straight up and down without running out of Z, but on a 45deg angle, i can easily reach the top of the part, without running out of Z travel. If I leave my Z soft limit on, it will stop the program as it calculates it hitting the z-soft limit.
The opposite issue arises in a similar situation, where I should hit my Y soft limit due to the angle i'm on, but due to the TCP being well within the Y soft limit the program thinks it's fine. So the simulation doesn't tell me that i'm going to hit my soft limits, and I end up hitting my hard limits - which is not ideal.
Is there any way to fix this so that the soft limits use the actual axis position rather than the TCP?



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Re: Soft Limit issue with 5-Axis Positioning

Post by TomKerekes » Sun Nov 22, 2020 8:08 pm

Hi Matt,

Here is a Patch for Version 4.35e that should apply Kinematics when checking Soft Limits. Copy these files:


to the \KMotion\Release folder.

Sources if needed are located here.

Please let us know how this works for you.

Tom Kerekes
Dynomotion, Inc.

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