Volumetric Lattice Tips and Tricks | Product Design Extension |

[@keal.vietnam]

Very nice tutorial , perfect and beautiful design with Lattice, save material when 3d printing. Sir, can you do more joints and mechanical movements in fusion 360, I'm really looking forward to it.

[@LearnEverythingAboutDesign]

Sure thing. I am planning to update my intro to fusion series. I do have several videos specifically on suspension kinematics/joints in fusion. Is there anything specific?

[@janosadelsberger]

Another thing to consider when not using offset and treating the lattice itself as a structural component is that stresses concentrate on the transition from the solid piece to the lattice. That's why I like to use a small offset at the transition. To really get a good result nTop suggests that you do a boolean intersect with the original geometry to get rid of any weird artefacts resulting from the implicit modelling. I've yet to try this in fusion but it really cleans up the outside faces a lot. nTop does this before meshing so I guess you would need to overbuild the mesh lattice and then do a boolean intersect with the meshed original part if that makes sense... btw. as this is an appearance you can use only one lattice per component, you'll need to create a new component if you want more than once lattice part in your design.

[@LearnEverythingAboutDesign]

Yup. at the end i state that having a small offset on all the faces the lattice touches the solid is likely a good idea and show some of the intersection issues between them. It is by no means a perfect solution. In Fusion if you just combine the two and go to slice it for 3d printing it gets confused, so I don't like to use that method (specifically in Fusion). I think nTop is the top tier solution for this kind of thing, but it doesn't come cheap! :) While Vol Lattice is in the extension and does increase the cost of Fusion you would still be 10x cheaper in Fusion. nTop having more simulation based results and a more complex lattice control is certainly the solution if you are doing this sort of thing. For me this in Fusion is "cool", but not quite useful yet, at least I haven't come across the ideal application. I have played around with shape optimization and using the load path result as a core(solid), and the original (pre shape op) shape as the lattice. but again this is speculation as to the impact the lattice has on the design. Only physical testing of various samples would give us those results.

[@mustafax5165]

Hello, I am designing a robotic arm on lattice structure for my school graduation homework, but when I switch to the analysis part, the part I designed with lattice structure does not appear in the analysis program, how can I fix it?

[@LearnEverythingAboutDesign]

you can't sadly. I mentioned somewhere in the video, maybe near the end, that the vol lattices in Fusion is a mesh. You can't use a mesh for FEA because oddly enough it can't mesh it. It needs a solid body. So the method I showed focuses on the outside shape being mechanical and the lattice being a bit of a filler. IF you somehow know the mechanical properties of the lattice then you can have 2 solid bodies that are bonded in the simulation. The inside solid body would need the mechanical properties of the lattice added. The trouble is figuring that out. Generally it would be done with testing as the strength is directional and simulation really wants an isotropic property. About the only thing you could do is go to a software like nTopology. I don't know if they have a student version or not.

[@janosadelsberger]

I don't really agree on the statement that it's mainly for light weighting, this is awesome for ergonomic purposes where you're able to replace foam with lattices which is much more powerful. Variable density and local variation of stress-strain behaviour through change of the unit-cell is a big thing here!

[@LearnEverythingAboutDesign]

Hi Janos, my statement was aimed at Fusion and specifically because we can't simulate the performance of the lattice structure. The closest thing I am aware of is nTopology for being able to generate lattice based on simulation results. Once its a mesh in Fusion we can't re-mesh it to run an FEA study on it, so for the purpose of building a lattice on mechanical parts with Fusion it won't be a performance thing, at least in my mind. I hope one day we can get a solid lattice structure that can be properly evaluated. I don't currently know of a resource that has mechanical properties of lattice structures like you find with say the yield of solid material.

[@janosadelsberger]

@@LearnEverythingAboutDesign I talked with a guy from Fraunhofer after FormNext last year and they actually model the properties for the resulting meta-material and plug the modelled parameters into FEA because simulating complex lattices is super resource intensive.

[@LearnEverythingAboutDesign]

where do they get the properties from for the material though? Manufacture it, test it? I would image the structure is not modeled as Isotropic, maybe orthotropic? Not something Fusion could simulate unless it was broken down into an isotropic "worst case" probably. very interesting.