To design the robot this year, I am using Autodesk Inventor 2011 Pro Student Edition. I am trying to enter a manual density for a sheet of aluminum honeycomb material (6 kg per cubic meter) and I can’t seem to figure it out.
All of the forums tell me that I should be able to go into iProperties and, under the “Physical” tab, manually override the density value, but this never seems to work. Nothing happens when I click on the dialog box and try to enter a new value.
I am using the FIRST Robotics student edition of Autodesk, available for download here.
First, you may find it easier to find your density in g/cm^3 (or lb/in^3, whatever you’re working in).
Second, the easiest way I’ve found of doing this, though jank, is to edit the mass until the density is adjusted to where you want it to be. It sounds like you’re in the right menu, just edit the mass instead of the density, because density is probably in a gray box.
If you have time, make the honeycomb material using a pattern. It takes a little practice, but its a good exercise and its not that difficult. It also makes for a really cool looking drawing.
But if you wanted to just go to the iproperties and change the material properties, its been awhile since I have done it (I have been using Solidworks lately) but I remember just typing in the density to get the correct weight. but its been a long time since I have done anything like that.
Thanks guys. I’ve noticed all of these fixes, but I was hoping for a direct method of manipulating the density, but it seems that there is no way to do it without spending around $5,000 for the full version…
Creator Mat, thats pretty much what I have it as right now, but a solid block of aluminum that size weighs a LOT more than the honeycomb material (I actually have a sheet of the stuff at school, but that’s an hour’s drive away).
If I have the time, I will probably just end up making a hexagonal pattern and sandwich it between two sheets of aluminum. If not, I’ll just manually override the weight to something close.
I don’t think there are any restrictions on the software. I’m currently running 5 Autodesk “student” programs and the only difference I’ve noticed is the plot banner…nothing seems restricted. But I’m going to check on my Inventor 2011 tomorrow. I know I’ve manually overridden density values in the past on earlier versions of Inventor.
A quick solution to changing the material density if it seems “greyed out” or uneditable, is to simply make a new material and enter the properties you want. We ended up doing this for some rather complex designs on our machine, and as long as the hand calcs are done correctly, you will get a weight within 5% of the actual.
Note: There is not supposed to be any limitations between the “student” and “regular” versions other than the plotting banner (watermark), and that you can’t import a student version into a regular version (or the other way around can’t remember). If this doesn’t work please let me know.
You can in fact do both, as I do almost daily with files from AutoCAD, Revit Architecture and 3ds Max. Most of the time a warning prompt it displayed when you go from student to full stating that the plot banner will remain.