Some Axes0 values for AnySeg may not work

Hi,

I modeled the two-link assembly in SolidWorks CAD system and tried to its AnyBody version model.

I attached its SolidWorks capture file and its AnyBody capture file.

Also I attached the zip compressed file for the AnyBody project.

But I could not reproduce the AnyBody model that has the same initial kinematic configuration of the SolidWorks CAD assembly.

I could find the reason that Axes0 values for ‘RTIB_1’ AnySeg in my example may not work. Its values are as follows:

Axes0={ {-1, 0, 0}, {0, 0, 1}, {0, 1, 0} };

Even if I commented out this line, it does not effect on the result.

I’d like to ask of you whether there are some special values for ‘Axes0’ that I should avoid to use.

Best regards,
Moonki

Hi Moonki,

I am not sure i understand the question.

I have tried to add these joints to the model



  AnyStdJoint fix={
  AnyFixedRefFrame &ref2=Main.EnvironmentModel.GlobalRef;
   AnyRefFrame &RefNode0=..Segs.RTHI_1.Joint0_RTHI_1_RefNode;
 };
   AnyKinEqSimpleDriver drv={
    AnyRevoluteJoint &ref1=.Joint0;
DriverPos={pi};
DriverVel={0};   
   };


and then it runs, but complains about gimbal lock …

Please if you can add more details on what is the issue.

Best regards

Hi Søren,

The intention of my question is that the initial position and orientation of AnySeg are determined by its ‘r0’ and ‘Axes0’ properties.

Besides drivers and constraints, I should think that the initial position and orientation of all AnySeg objects should represent their ‘r0’ and ‘Axes0’ values.

As I told in my first post, some Axes0 values like this may not work properly:
“Axes0={ {-1, 0, 0}, {0, 0, 1}, {0, 1, 0} };”

This means that initially the local x-axis of this AnySeg should be represented as (-1, 0, 0) with respect to the global coordinate system. And the local y-axis should be (0,0,1) and the local z-axis should be (0, 1, 0). But this may not work.

Thanks for your reply and I hope to get your additional help. :slight_smile:

Best regards,
Moonki

Hi Moonki,

Thanks for the extra explanation, this looks like a bug.
We will try to debug it and find the explanation.

Thanks for making us aware of it.

Best regards
Søren