topic Re: Simulate: assigning a Point Mass (Manual) at a pre-determined Point in Fusion Design, Validate & Document Forum

Simulate: assigning a Point Mass (Manual) at a pre-determined Point

iakovUmrikhin — Thu, 14 Apr 2022 17:47:11 GMT

In Simulate, I want to use a Point Mass to represent an attached item. It's easy if I just want to use Absolute Position relative to the Origin- already used that method before. However, I'd like to be able to model a Point in Design workspace that represents the CG of this attached item, then pick this point for a Point Mass in Simulate.

However, when I try to do this, there seems no straightforward way. Am I missing something? I'd hope to use either of these methods:

a) Click a Point to use as Point Mass location

b) Click a reference (some arbitrary origin), then enter offsets. This is how I established the Point in a) in the Design workspace. From the Autodesk Help I've found, this seems to be somewhat similar to the intent of the "Reference" option in Point Mass (Manual). However, I'm struggling to get this usable- it doesn't seem to work very well.

Any advice would be much appreciated!

Re: Simulate: assigning a Point Mass (Manual) at a pre-determined Point

hamid.sh. — Fri, 15 Apr 2022 02:17:24 GMT

As far as I know, unfortunately Point Mass (Manual)'s reference can only be a body vertex, edge or face. But you can do this: in Design workspace make a Surface body that has a vertex at your point of interest. Its shape doesn't matter, you only need a vertex at that point. For example here I used Surface Loft to a point in my sketch. Now in Simulation workspace you can use this vertex for the reference of point mass:

I should also note that Pre-check reports this surface body as free, but it is not included in the simulation.

There is also one other thing that might be helpful; if you have designed the loading body as well you can use Point Mass (Auto) and select this body. Fusion will replace this body with its calculated mass (which can be overridden) at its calculated CM, and remove its geometry from simulation:

Both example files are attached.

Re: Simulate: assigning a Point Mass (Manual) at a pre-determined Point

iakovUmrikhin — Wed, 20 Apr 2022 20:25:56 GMT

Thanks Hamid- using the Surface vertex approach will do the job (shame it spits out errors in Pre-Check but seems to be the current way to do it). Hopefully F360 will get to the point of allowing a "Point" as reference!

Re: Simulate: assigning a Point Mass (Manual) at a pre-determined Point

aleksei_ovsienko — Tue, 19 May 2026 07:49:01 GMT

Jesus Christ Almighty... This this a thread from over 4 years ago. And the problem is still not solved. I still have to use weird workarounds to create mass points.