topic Re: Calculate the transform matrix between two CSYS features in 3D Part & Assembly Design

Calculate the transform matrix between two CSYS features

tbraxton — Fri, 31 Jul 2020 00:20:22 GMT

Is anyone aware of a method to obtain the transform matrix between two CSYS features using built in Creo functions?

The measure transform function generates the transposed matrix of the matrix which transforms coordinates based on the second selected CSYS to that based on the first selected CSYS. I would like to obtain the transform matrix but can not find any internal function available for relations or a direct analysis to generate this matrix.

I would then use the transform matrix values in some relations to drive additional features.

Re: Calculate the transform matrix between two CSYS features

DavidBigelow — Fri, 31 Jul 2020 11:40:47 GMT

native within Creo -- I don't think so. Unless you set up an analysis feature between your references (or something)?

If you need more detailed access - you might look at CREOSON (Open Source Creo Automation)-- there is a function in there called:

file : get_transform

Sample Request:

{ "sessionId": "~sessionId~", "command": "file", "function": "get_transform", "data": { "asm": "plate_assy.asm", "path": [ 54, 23, 45 ], "csys": "CS0" } }

Sample Response:

{ "status": { "error": false }, "data": { "origin": { "x": 380.0000554810615, "y": 120, "z": 1.000000000017174e-20 }, "x_axis": { "x": 0, "y": 1, "z": 0 }, "y_axis": { "x": 1, "y": 0, "z": 0 }, "z_axis": { "x": 0, "y": 0, "z": 1 }, "x_rot": 0, "y_rot": 0, "z_rot": 0 } }

Once you have that... I think it would be pretty easy to compute your transform.

Dave

Re: Calculate the transform matrix between two CSYS features

Tdaugherty — Fri, 31 Jul 2020 12:49:31 GMT

I don't know of any native commands that can calculate the transform. There is a pretty slick workaround that we use to calculate coordinate system offsets/angles that may be useful to you. Very helpful when designing end of arm tools for robots.

Assuming you have coordinate systems A and B, and you need to know the offset dimensions and angles from A to B.

Here's the steps:

Identify coordinate systems A and B
Create a new coordinate system
Select coordinate system B as a reference for the new coordinate system
Select coordinate system A (reroutes constraint of csys so that it's tied back to A with dimensions)
Click OK

See the attached video clip for more details.

Re: Calculate the transform matrix between two CSYS features

tbraxton — Fri, 31 Jul 2020 23:56:49 GMT

I found an older thread that is closely related to what I am trying to implement. I think it is a possible solution although I have not verified the Euler angle calculations work for my test case yet. It is worth looking at for anyone needing to use transform matrix elements in relations.

https://community.ptc.com/t5/Assembly-Design/how-to-retrieve-ALL-csys-parameters/td-p/58618