8 Replies Latest reply on Jul 12, 2018 12:18 PM by phiet

    Different coordinates for layout and 3D layout?

    milostnik

      Hello Folks,

       

      I have something that I struggle. And it has to do with the coordinates of a layout and a 3D layout.

       

      In this example I designed a board and I put some holes. In this holes I have to put some spacers to attach this board to another.

       

      Now when I place the hole, I use x/y coordinates that start from the lower left corner of the board. I can place a hole e.g. at 31.4/9.4.

      When in 3D I position a spacer the coordinates that the spacer has to be place to is different. In this example it is -141.7/-89.1

       

      So my question is: why are the two coordinates different?

       

      Thanks

        Matija

        • 1. Re: Different coordinates for layout and 3D layout?
          ed_smith

          They do use the same origin.

           

          I think that the data inside your spacer mechanical model is not at 0,0 but offset from that by some considerable distance.

           

          If you enter 0,0 for the x,y values in the mechanical model properties dialog, if the spacer is not over the top of the pink 3D origin symbol then its your spacer that needs modifying.

           

          Regards, Es

          1 of 1 people found this helpful
          • 2. Re: Different coordinates for layout and 3D layout?
            milostnik

            Hi Ed,

            so in your mind the spacer, that I imported as step model, and I have no controll of, is mangled?

            Do you have any idea on how to move the origin of the step model to get alignment.

             

            Thanks

              Matija

            • 3. Re: Different coordinates for layout and 3D layout?
              ed_smith

              I wouldn’t use the word ‘mangled’, that implies somehow that it is corrupted. I would prefer to say that whoever created it decided not to put the center of the spacer at 0,0 (Probably for some very valid reason) but if you want a spacer that can be used multiple times in multiple designs then you probably want the oorigin of the spacer to be in its center.

               

              If you dont have access to an MCAD system then there’s not much you can do about it apart from look for another one on Content Central (or somewhere).

               

              Regards, Ed

              • 4. Re: Different coordinates for layout and 3D layout?
                milostnik

                Hi Ed,

                thanks for the explanation. By requesting a new model, now I got exactly the right coordinates.

                Here the newly imported spacer with coordinate 0/0/0. Exactly at the origin of the board.

                 

                Spacer_at_zero_origin.png

                Now putting the exact coordinates matches the coordinate of the bord mounting holes.

                 

                Thanks

                  Matija

                • 5. Re: Different coordinates for layout and 3D layout?
                  phiet

                  For MCAD/ECAD to work, I realize that the origin of 2 systems have to be perfectly matched.

                  Where do you put your origin so 2D match 3D's ? for a spacer, 0,0 can be at the center of the hole, but for any regular part like BGA or any IC ?

                  Thanks

                  Phiet

                  • 6. Re: Different coordinates for layout and 3D layout?
                    milostnik

                    Hi Phiet,

                    you have to differentiate between a model that is linked to a part and a mechanical part that is added to the design.

                     

                    In my case, the spacer was an added mechanical part that was not part of the board, but I needed to add to then add another board as an added geometry to build a mechanical assembly and check some mating.

                    For this, I found out, that is important to have the 0/0/0 point such that you can place the mechanical part anywhere on your board, by using the same coordinates that the board uses.

                     

                    In the case of a component, like IC, FPGA, resitor, transistor, trafo, and so on, that is placed on the board, and is part of the BOM, every part number can have a geometry model linked to it.

                    For this there is a procedure of mating and putting the surface together that allows to reposition the geometry regardless of the origin of the coordinate system of the model. Once this relationship is established, you use the origin of the cell as it is described in 2D, aka like you place this component in layout.

                     

                    Hope this helps

                      Matija

                    • 7. Re: Different coordinates for layout and 3D layout?
                      ed_smith

                      If I might try to add to Matija’s excellent response:

                       

                      if you use the optional 3D model library, M3DL, then there are a couple of commands in the toolbox that you can use to search for component models and have them automatically aligned to your component footprints.

                       

                      If if you manually import a component model (from somewhere like 3D content central) there are a couple of commands you can use to simplify the job of aligning it to the components footprint.

                       

                      In in either case, once you are happy with the alignment, you can push the mapping of 3D model to part into the central library so that it can be reused in subsequent designs.

                       

                      Regards, Ed

                      • 8. Re: Different coordinates for layout and 3D layout?
                        phiet

                        Thanks Matja and Ed for clarification.