Announcements
Visit Fusion 360 Feedback Hub, the great way to connect to our Product, UX, and Research teams. See you there!
cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

mass properties

mass properties

We need center of mass, moment of inertias and other mass properties via the inspect menu and the option for it to appear in the analysis folder like a section analysis. X, Y, and Z axis need to be displayed (visible) while viewing mass properties (also needed for the measure tool).

The ability to add any one mass property to a bill of materials/cut list column and use as parameters in equation is also useful.

20 Comments

It can't be overstated how essential this is for anoyne doing mechatronics.

 

It'd be really great to have the ability to export center of mass, moment of inertia tensors, and joints for assemblies.. maybe also to have a (good / reliable / numerically stable / physically accurate) rigid body dynamics simulation system built in with a sensor / actuator API that lets it connect to an external controller in the user's favorite language.

Anonymous
Not applicable

for some reason I thought Fusion could do this, but I can't seem to find it anywhere.

I also think center of mass used to be in there in some dialog or another..

 

CM for a body or assembly should be a pivot point oriented with the principal axes of the moment of inertia tensor.

 

The program keeps track of materials and can already do volume integration so the work is basically done and this would be hugely useful.

 

One thing that would be nice is the ability to add an object and specify its center of mass, mass, and moments of inertia (I might want to put in a motor, battery, board, etc, but I either don't know or don't want to bother with modeling the internal details).

GPTech2444
Advocate

I can't find this feature in Fusion, does it not exist?

 

I need to know the weight of an assembly.

 

This idea is old http://forums.autodesk.com/t5/fusion-360-ideastation-request-a/additional-physical-mass-properties/i...

 

I think this really needs to be implemented.

 

Grant.

Wow there I am under my old account (samenor) asking for it too in 2013 😕

 

Total mass is there. If you can do that then (I presume) there is already something quickly integrating over the volume. If there is integration over the volume then finding the center of mass is just a matter of integrating the mass density in each small volume (already being integrated) times the coordinates and then dividing by total integrated mass. 

 

Moments of inertia aren't much harder. Surely somewhere there is an intern who has just taken calc 1/2 who could build this as a summer project.

GPTech2444
Advocate

Yes, I found it. Google bought me here and I couldn't find it in fusion. 

 

Then I tried help in fusion and it it sent me to this thread http://forums.autodesk.com/t5/design-and-documentation/is-there-a-way-to-measure-volume-or-mass-if-g...

 

Always the way. Smiley Happy

 

 

brianrepp
Community Manager
Status changed to: Gathering Support
 
Anonymous
Not applicable

An adjustable gravitation variable would be helpful. 

 

Any mass is going to be acted upon, I think that adding some form of manipulation to represent this effect is benificial. 

 

Center of mass is fine, though you might want to add heating/coolling  as well.

 

I'm sure any quantum variables will be tertiary.

keqingsong
Community Manager
Status changed to: Solution Provided
 
Anonymous
Not applicable

Inertia terms, and inserting custom coordinate systems to reference those inertia terms are necessary for any robotic\mechatronic systems.  I'd love to use Fusion for my real work, but until those features exist it doesn't make sense to use Fusion.  

 

I see mass properties exist, but I don't see where inertia terms can be found? 

Anonymous
Not applicable

This problem hasn't been solved. The status shouldn't be "solution provided". You still can't find center of mass or moments of inertia in Fusion 360. 

Yeah wow that's nuts.

 

Unless I'm missing something, it's absolutely not been provided and mass / higher moments of inertia are really not very hard to calculate (just a bit of integration), so this / http://forums.autodesk.com/t5/ideastation-request-a-feature-or/center-of-mass-and-moments-of-inertia... should be almost trivial to implement (and extremely useful for anyone working with nontrivial mechanical or mechatronic systems)

whunter
Advocate

SOLUTION PROVIDED: That's not true, it's a partial solution. I only see MASS, AREA and VOLUME.

 

CoG position and inertia values still missing, please change the status back to not implemented.

There really should be a way to downvote / remove «solution provided»

cglusky
Participant

I am a bit confused by "Solution Provided"  Still do not see center of mass/gravity in latest Fusion.  Lots of simulations that should require it to be computed.  Am I missing something?  Simpy providing mass for a single body is not good enough for our purposes.  We need center of mass for an assembly.  

 

[Edit]  I guess I am not missing anything.  I posted my comment and more comments appeared in the thread that say the same thing.

Yeah @cglusky @keqingsongsolution absolutely not provided.

 

Capture d’écran 2016-04-07 à 08.56.27.png

 

Mass is there but there is no center of mass let alone higher moments of inertia.

 

The most infuriating thing there is that getting the mass means that F360 has to be doing the integration to get volumes and CM is just weighting coordinates by that and dividing by the total mass (with higher moments being similarly trivial)

cglusky
Participant

@roambotics_scott Thanks for verifying.  We noticed in Simulation if you look under Loads there is a Gravity value listed in the tree.  We played around with one of our assemblies and it does seem to move when we move parts around.  If you right click on Gravity you can get a Property listing.  And... it has nothing useful.  So it all seems to be there, just not properly implemented.  Can you verify on your end?  Thanks!

 

That's just the force of gravity applied in simulations (incidentally AD - might be useful to have a handful of other values in there for places like Mars.. though if you're going there you're probably much more concerned with acceleration / vibrations during launch, reentry, and landing than any static forces on the ground)

cglusky
Participant

Yep.  Just looked like the point where the little yellow vecotr marker was resolving (which does move with parts/masses being moved) could have been center of gravity/mass since we are dealing in (theoretically) rigid bodies.  And we really just want the location of the point where that pretty little yellow vector marker is pointing on the screen.   Thanks for checking!  Yes, let's have AD fix the static properties for Earth G before we start asking for Mars use cases and/or dynamics.

keqingsong
Community Manager
Status changed to: Implemented

Can't find what you're looking for? Ask the community or share your knowledge.

Submit Idea  

Autodesk Design & Make Report