Grounding versus Match Coordinate

Pioneer
Pioneer

Hey all,

 

Has anyone played around investigating the performance advantages/disadvantages of using the match coordinate instead of grounding? I pointed out to long term SE users here that ground doesn't actually fix a part in space as it is free to be moved by either dragging or move on select.

 

To me this indicates in the the constraint solver would have to work harder to first identify the grounded components origin in space, and then solve everything relative to it. In small assemblies no big deal, but I am wondering if our large constraints would benefit of using match coordinate as a best practice.

 

Anyone have any insight?

5 REPLIES

Re: Grounding versus Match Coordinate

Phenom
Phenom

Match co-ordinates places 3 planar alignments between the implied planes of the co-ordinate systems, so it is no different to mating faces or base reference planes.

Ground does lock the part in position, unless, as you say, you choose to move it by dragging or by using the steering wheel - but this is true of any part, even with constrains applied.

The advantage of grounding is that you can use occurrence properties to change the position.

 

We use a lot of grounded parts - for reasons I have explained in other threads.

HP Z420 16GB RAM
Quadro K4000
ST7 MP10 on Windows 7 Pro 64.

Re: Grounding versus Match Coordinate

Siemens Phenom Siemens Phenom
Siemens Phenom

As beachcomber stated, Match Coordinate Systems is just a UI shortcut for creating 3 planar relationships between the coordinate system planes, so there are actually more relationships to solve in that case instead of just 1 for a ground relationship. There is an option to prevent moving grounded components in the Drag Component command options so they stay fixed, but with the Steering Wheel there is not.

 

Greg

Re: Grounding versus Match Coordinate

Phenom
Phenom

@GregLuckett - there is also a setting on the 3Dconnexion control panel to prevent parts moving on select.

Don't think it moves grounded or fully constrained parts though because I sometimes use it when I need to check if a part can be manoeuvred into position for fitting - disable a constraint or two and you can rotate and move it.

HP Z420 16GB RAM
Quadro K4000
ST7 MP10 on Windows 7 Pro 64.

Re: Grounding versus Match Coordinate

Honored Contributor
Honored Contributor

I use grounding all the time. But it's a result of my ordered sheet metal modeling process. 

When I create a part using a sketch and plane location to locate a part, mates can sometimes move the part without that intention. I have to ground all my parts to keep them free to re-size yet stay where they are designed.

Re: Grounding versus Match Coordinate

Valued Contributor
Valued Contributor

@Sathersc86

 

We use a mix of relationships, grounding and "matching of co-ordinate systems".

 

What we model and where this model fits into the bigger scheme of things determines what type of spatial positioning is used.

 

Whenever I train someone new to Solid Edge I always show and discuss the following video as part of their training and I ensure they fully understand it, and are able to demonstrate these relationships to me.

 

Hopefully you will gain some benefit from this video.