CAD designer needing help with Blender physics simulations

First, some background info:

I work for a thermoforming company who makes packaging, with food packaging being a large portion of our business. Take-out containers, pre-packaged foods, prepared food containers from your local grocery store chain and baked goods containers are the sorts of products that we produce. I create conceptual containers and packaging in CAD with the purpose of creating visual representations of what the final, manufactured product would like like, to help determine exactly what the customer is looking for, before any engineering or production takes place. I create the products in CAD, render them using Keyshot using the appropriate materials and create presentations showing the customer the options.

Showing renderings of the empty containers is a step up from the majority of our competitors, who resort to just CAD drawings. Whenever possible, I like to also show the containers filled with product. When this is a few larger items (cupcakes, brownies or a sandwich, for example) this is easy. I either make, purchase or sometimes using photogrammetry for items like this. If the container is to be filled with a larger number of fairly simple objects (candy, cherry tomatoes, berries, etc.) I’ve used Blender to make simple rigid body simulations to drop the items into the container to fill it, export the resulting simulation and combine that with the CAD files in Keyshot to render it (example image below).

The problem comes when more complex simulations are needed, for example, filling a container with a salad with a variety of different contents, both soft and rigid bodies and very odd shaped items, like lettuce leaves. I haven’t been able to do this in Blender. Once I start trying to introduce something like a lettuce leaf, all sort of problems start, including it just falling through the containers.

One other thing to keep in mind, 90-95% of my time is modeling in CAD, only 5-10% of my time is spent in the visualization. While I’m willing to learn what I need to, I also don’t have the ability to spend hours creating and running simulations to fill containers. While my employer would love to be able to present containers realistically filled, the amount of time dedicated to just that sort of visualization is limited.

My questions; 1) is this something that should be possible with Blender? 2) Is there something better to use for my narrow focused needs? 3) Does anyone know of resources, courses or even individuals who might be potential sources of information to help me work through this? I’m willing to invest my time and (my employers) money to help overcome some of the issues I’m having.

Any help, suggestions or insights would be appreciated.


Or here is a rendering of the Blender animation, render in Keyshot:

I just need to do this with more difficult models, like the elusive salad.

Well, Blender’s physics simulations capabilities are quite limited compared to professional engineering software. If money isn’t an issue, you could try a commercial CAE structural mechanics software (LS-DYNA, Abaqus, …). From my impression the contact algorithms of these are also not perfect but surely better and allow for much more tweaking. Also performance and scalability is much more optimized.

$6000 software seems like hella overkill for simulating a rendering of salad…

@mcramblet, Do you render these containers from a fixed angle? If so, then I would recommend taking a photo of the salad from a similar angle and faking it in there.

Obviously, rendering salad is a complex issue that most people (and global brands) sidestep:
image image

I have “faked” it before, either with a fixed angle or even creating an internal volume object and applying a texture to the object. I’m hoping to come up with something that is more realistic and allows for views from multiple angles, or even animations. Maybe that’s just too tall of an order, and why I haven’t been able to find any good examples of others doing it.

I have looked at these types of programs (and have access to some), but didn’t find anything that looked like it would work. All seem to be geared towards solving specific engineering problems (heat, stress, load, etc.), many only work with CAD input and none are geared towards generating results that can then be rendered.

Well, for simulation you should use a proxy object, resembling the render object only accurately enough to allow the contact algorithm to place (and maybe deform) it correctly.

But thinking about how people are doing meadows or trees, by using particle systems, maybe something could work here, too. There is the matter of getting intersecting objects, though (which don’t really matter in these cases, except if looking very closely). But when fixing the visible ones by hand afterwards, it could be okay. Your example suggests that there aren’t that many objects for this to be impossible.

So the idea for doing it in Blender would be:

  • create simple, unproblematic proxy objects and do rigid body sim on these
  • replace the proxies with the ‘real’ detailed objects
  • fix visible geometry intersections by hand