Using Part Consolidation to Optimize Parts for Additive Manufacturing

ALEXANDER JONES: Hi. Welcome to the Autodesk University talk on using part consolidation to optimize parts for additive manufacturing. My name's Alexander Jones, and with me is Luke Ice. And we are both engineers with the Johnson & Johnson 3D printing team. This course will cover many things on part consolidation.

To start, we will do an introduction on additive manufacturing, which will be involving what is additive manufacturing and what unique design capabilities there are with additive or 3D printing. We'll then go into understanding part consolidation, and that will cover the benefits of part consolidation and the motivations of using part consolidation. And then we'll end with Luke giving an example of using part consolidation in the real world.

So to start off, an introduction into additive manufacturing-- so what is additive manufacturing? Additive manufacturing, or AM, is the process of additive building up a part one layer at a time. 3D printing-- 3DP, often called-- and AM are often used interchangeably. 3D printing is the technology and AM is when it is used to manufacture something. Technically, you do not-- all 3D printing is not AM, because often, with R&D-- or parts where it's not being manufactured is not AM.

And AM doesn't necessarily have to be 3D printing. But for this case, we're going to be talking about 3D printing used in additive manufacturing. So there's many different types of 3D printing. There's many different technologies, ranging from extrusion-based-- kind of like a hot glue gun-- to laser-based ones. And in these, there's many different materials that you can print with, including metals, polymers, ceramics, and even biologics.

So if you look at the image in the bottom right, you'll see some icons displaying the various types of 3D printing. So starting on the left is material extrusion. This type of technology is the kind of printer that many people have in their homes, and libraries, and schools. It uses a filament that is fed through a nozzle and melted. It kind of operates like a hot glue gun, except that it's often colored, and then it will do a layer by layer by layer until the part is formed.

The next one is material jetting. This kind of operates like a inkjet printer, except there's multiple layers stacked on top of each other. It ejects out a polymer that gets-- a resin that is-- then has a light that comes over, and cures it, and solidifies it. And it does that layer by layer by layer until the part is formed. The next is vat photopolymerization. This is also referred to as SLA. It's one of the first 3D printing technologies.

This is a vat of a resin that a laser or a light comes through, and selectively cures it into a solid part. You'll see the image at the top right. Those are hearing aids that were made with that photopolymerization technology. And with hearing aids, over 96% of hearing aids today are made with 3D printing. They're used in 3D printing for the personalization. It's costly to have an artisan make custom hearing aids, so 3D printing is used to do it effectively and easily.

The next is binder jetting. Binder jetting uses a sand or a powder type material. And after each layer, a fusing agent, like a glue, is placed over it, and it bonds all of those powder together, and then does that layer by layer until the part's created. The next is powder bed fusion. This is where you also have a bin full of powder-- could be metal or polymer powder-- and a laser is coming through, and it is selectively sintering or melting that to form a solid part.

The last is direct energy deposition. This is often used in manufacturing sites on five-arm tooling. It is unique, because it can build on top of parts. What it does is it sprays a powder-- it's always metal-- and has a laser that hits the powder as it's in midair to fuse it into a solid material. And you can see this image up here is using powder bed fusion. And you can see some of the unique geometries that you can do with that technology.

Next we're going to talk about the unique design capabilities that 3D printing allows. So a lot of times, 3D printing is utilized because of the design advantages that can help enhance the part functionality. Often, cost is not the driving feature, but the design advantages are. So the first one that is a very common used thing is as-printed assemblies. So this is when we are creating an assembly of parts-- either they're moving or maybe they're static-- but they're all printed together in the assembled form.

So when it comes off the printer, it is fully assembled, and often, like this one here, it actually cannot be disassembled. So this is unique and has its own needs. Oftentimes, we'll use this when you don't want to prevent the disassembly or you need just to remove the assembly requirements.

The next is light-weighting. So you'll see this bracket here with a lattice in there. So lattice and generative design methods are used to reduce the weight of the part. Often there's a need to lighten parts for ergonomic reasons, if you're lifting parts and carrying them around, or also if the application just needs it bit lighter. For example, aerospace-- they're always trying to reduce the weight of parts that go on planes to make it more fuel-efficient. So a bracket like this would be made. So it continues to have the same strength capabilities for the stresses that this bracket sees, but it's lighter and more efficient for their use.

The last here is part consolidation, which is what we'll be talking about after this as well. So this is when we'll take a multi-piece design and combine it into a single form. And it makes it lower cost for manufacturing, and can improve the functionality. So for this example here, with the venting, you-- after this is printed, this one is ready to go to be installed. But the one on the left, which is more conventional-- it needs to be fastened and assembled, each single piece here. And with venting, there could be some gaps. There could be some misalignments and a lot of fasteners that are needed. So all those issues can be eliminated by creating one single part.

The next section is understanding part consolidation. So what are the benefits of part consolidation? So some of the benefits are removing the need for the parts to be assembled with welding, pinning, bolts, or other methods. And with welding and some of those, there's a lot of validation efforts that need to go in to make sure that your welds will meet the requirements of the FAA, or the FDA, et cetera. So when you go and have welding or pinning, then you don't have to validate it. So that is a huge benefit for many products.

It also just removes the assembly step fully, and so you can save a lot of manufacturing time by skipping that step. And saving time saves money, so that is often a big savings. And also, reducing the number of parts prevents a lot of tolerance stack or alignment issues. So if you have a large assembly of parts, there's a small chance that, if every single one is slightly askew, by the end the tolerancing is way off. So by combining them all into one single piece, you won't have any misalignment.

And then, overall, it just will create an easier changeover process. If your production line has to do a lot of changeovers of parts, by having less parts, less fasteners will save them time, and you can be creating more products. So the example on the right is an example of using part consolidation. You can see on the left part, there's about 20 parts there. And using part consolidation, they were able to transform this assembly into a single part, like this.

By doing this, they were able to reduce the production time by 75%, and create a better and lighter part. And then, instead of having any errors with assembly, they removed the need to assemble all together, eradicating any errors. And with part consolidation, there's a lot of motivations to do it besides just the benefits. And it's key to ensure that you are doing this for the benefits, and you're not just doing it for the sake of doing it, because often adding extra design time, going through all of this may not be worth it if you're not-- if you don't have benefits that part consolidation can provide.

So some of the big motivations to do it are reducing the number of SKUs. So if you have a lot of different parts, and fasteners, and all sorts of things like that, you can print it all in one piece, and so you have a single part, or a lot less than before. And this can be great for reducing spare parts needed and items like that. In the middle, you'll see maximizing structural integrity. So the picture there shows the first 3D-printed bridge. So with that bridge, it's all one solid piece.

So you would imagine, with a traditional bridge, there's a lot of finite element analysis and a lot of work gone on each fastener, each piece to make sure that-- are they going to break apart where they're connected, or is it all going to be strong enough? But by printing it all in one piece, you don't have to worry about a bolt becoming loose or a weld that's not appropriate. By printing it all in one piece, you can maximize that structural integrity.

And the last is reducing assembly processes. So you can see a man there welding. Removing that weld can save a lot of energy and effort, not only just in the welding, but in making sure the weld is appropriate. A lot of medical devices that have welding have to do a lot of testing of destroying welds to make sure that they are to code. So you can prevent a lot of this extra validation efforts and just the efforts in production. So now I'm going to turn it over to Luke, and he is going to walk through an example of applying part consolidation.

LUKE ICE: Thanks, Alex. So originally, this bracket is used to hold a series of lasers and mirrors used in a robotic arm surgery on the eye. So it's obviously very delicate. This image doesn't do it justice. It's actually a very small part, about 3 and 1/2 inches in height. Originally, it was a series of six pieces of machined aluminum that were then mechanically fasten together. You can see the series of bolt holes in the-- each of those plates.

So the request was to consolidate this part to eliminate having to assemble it, and then also eliminate any of the real small features, as far as the assembly process with the small screws and the fasteners. So we started to look at the part, what we can do to, one, start to eliminate the holes, and two, put this into an orientation where we can print it effectively. So we were able to bring all of the components together, use a Boolean operation to unite them, and we were able to eliminate all of the fasteners.

If you go to the next slide, we were able to add some fillets and blends that made it a little more structurally sound. There was less stack up, when you're positioning the pieces and assembling them. And actually, this step was a pretty successful step for us and for them. We were able to print this, reduce it from six pieces down to one, and eliminate the fasteners.

The caveat to this design right here is that, originally, this was designed using plates, so we had a lot of material that was unnecessary. And in the load case on this is very small. It's just a series of lenses and lasers. So it was way overbuilt for what the needs were. So we ended up taking this step further in Fusion 360. We put the load cases in on this part, put some of the boundaries and some of the limitations to it, chose an orientation that we felt would be appropriate.

We actually used generative design to further consolidate from the six pieces down to one piece, and that one piece into a much lighter, smaller piece that still has the strength needed for the-- to be fully functional-- but was able to reduce the volume by almost 80%. This is the end piece that we ended up launching with. It was cleaned up from this a little bit, but this was the basis for that generative design.

It satisfied all the loads, printed, and it worked really well. And it was a great example on taking the steps of part consolidation-- actually using that to drive the final design. So we used Fusion 360, which-- Autodesk has a lot of resources available to you-- step by step guides and explanation of the workflow to use that. It looks and seems like it'd be a challenging thing to do, but it's really broken down in simple workflow that any competent CAD user can successfully generate alternative designs that are organic and printer-friendly.

There's a lot of parameters you can set inside the workflow that-- to look for the quickest build time, the least amount of material, the least amount of support structure. Any of those factors that may be critical to you can all be factored in when you're setting up the part to run the algorithm. So there's a lot of resources from Autodesk. It's a great opportunity to enhance your ability to design a part that is functional and printer-friendly.

ALEXANDER JONES: And that's the end of our course here. Thank you for participating. And I hope you enjoyed it and can utilize part consolidation in your work. Thanks.