Three Trends Reshaping Mechanical Design

Let’s talk about the fundamentals of mechanical design. There was a big change back when computer design software came out. It was a big state change for the approach of mechanical design because those capabilities were very powerful. They could allow engineers to do things they could never do before. We’re now on the verge of the same type of state change in mechanical design. There are emerging technologies that are going to make a huge impact and open up a lot of new possibilities in terms of design.

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The Challenges of Traditional Mechanical Design

First, it’s important to understand what are the primary levers that mechanical engineers can pull today in terms of really making a difference with their designs. When it comes to developing a mechanical design, there’s three things that mechanical engineers can do to affect performance, capability and requirements fulfillment.

One is developing the shape. I call this macro geometry. Macro-geometry determines the outer shape of the component and maybe of the assembly. There’s lots of capabilities that we’ve had here for a while and some new capabilities. Parametric modeling and direct modeling have been around for a while. Parametric model allows you to work through features and parametrics. Direct modeling allows you to push and pull geometry directly. Subdivision modeling is a new one. It has become more widespread recently. You can progressively add controls. It’s similar to direct modeling, but with a little bit more organic control.

Another one is micro-geometry. Now to date, there hasn’t been a whole lot of control for mechanical engineers here. This has been a lot of solid components or solid geometry. You could get down to micro-geometry if you really wanted to model very small details. But that could get very taxing on the computer-aided design software and computer hardware. You can get into lots of performance issues, but today it’s mainly just solid geometry that you work with.

The last one is material properties. To date, you have materials selection that is basically homogenous. You have the same material properties in any spatial direction. You could select one. There’s been lots of advancements with composites and things like that. But in general, there hasn’t been a whole lot of control with material properties in micro-geometry.

The big lever that mechanical engineers have been pulling today to control their designs for components has been macro-geometry. They are changing and shifting the geometry and controlling what that outer shape really looks like. The primary mechanism for mechanical engineers to fulfill requirements, hit performance targets and fulfill costs have been geometric shape. That’s been limiting. It’s interesting because not only is it just geometric shape, but that geometric shape has been very constrained by how you can manufacture it.

If you’re using a casted components and then machining out of a block to control costs, you really are even more constrained. Three axis machining are only applicable to certain scenarios, right? You can’t necessarily get in really deep holes. If you want to avoid five access machining for costs that further constraints you. This has been the reality for a really long time. This is part of the context that’s changing for mechanical designers in all three of these areas.

Trend 1: Macro-Geometry Modeling

The first big change reshaping mechanical design has to deal with this macro-level or macro-geometry modeling. If you’ve been following the industry, some of this is going to be familiar. People are calling it generative design or topology optimization.

Macro-geometry is what we’re focusing on right now and really generative design is the big change here. An engineer will provide a lot of constraints and objectives to any artificial intelligence. Basically, this component of computer-aided design software applications will produce many different design alternatives. It will vary a lot of stuff. Sometimes this is just removing material like with topology optimization. In other cases, it’s using biomimicry algorithms to explore and develop organic shapes. This produces a lot of alternatives. It explores the design space for the engineer, but the engineer does have to define a functional design. What are the constraints? What are the things that govern the outcomes or the output of this effort?

Let’s talk about macro-geometry modeling for a moment or generative design. It’s really interesting technology. It’s very innovative and sometimes creates wildly organic shapes that people would never have thought of before. We’re seeing more capabilities emerge around taking cost into account, as well as manufacturing constraints. For example. if it’s going to be casted or machined. Or use additive functionality, which can enable a lot of these wild shapes that we’re looking at.

This bodes for a really interesting future for mechanical engineers. I could almost see eventually at some point the mechanical engineer being a manager of a series of agents that are going off and exploring different design alternatives. If you pair that with a voice assistant, it gets pretty interesting. You also pair that with augmented reality and now you have a completely different interface for what traditionally is being computer-aided software applications.

There’s a ton of potential there, but that’s actually the most mature of these three areas that we’re going to be talking about in this series. Micro-geometry modeling and material properties are just coming online or becoming more available now.

Trend 2: Micro-Geometry Modeling

Let’s shift gears and talk about micro-geometry modeling. We talked about macro-geometry modeling, which is enabled by generative design and topology optimization as well as other existing modeling methods today. To date, micro-geometry modeling has been focused on solid geometry. The idea here is you can leverage or define lattices from different shapes. You can define mathematical types of definitions for the geometry. Based on that, you can actually define different volumes or different geometric pieces that will be filled by these lattices. There’s all sorts of controls that are coming with this type of technology. It’s not just fill this volume uniformly with some type of geometry shape. You can define how that varies in different directions, X, Y or Z. You can have it be random. There’s all sorts of mathematical definitions that you can use to power this.

So what are the implications of this concept of micro-geometry modeling? Well this is a lever mechanical engineers haven’t had before. In earlier discussions, I talked about macro-geometry modeling was really the only real lever mechanical engineers could pull. Micro-geometry modeling opens up a whole new avenue.

You could have the same outer shape, but model it 10 different ways on the micro level with different lattices. They could have wildly different performance and still have the outer same look, shape, feel and aesthetics. This really opens up a brand new avenue of control for mechanical engineers to affect performance and fulfill requirements while maintaining all sorts of other things like outer fit. This is a big deal. This is one of the areas where there’s a big game changer in terms of technology that is emerging that can really affect how mechanical design looks going forward.

Trend 3: Material Properties

Next up, we’re going to talk about material properties. This is a front that’s seen some real innovative progress in the last five years. It’s an area where combined with additive manufacturing and some other manufacturing methods can really be leveraged to tailor material properties to fit instead of affecting macro-geometry.

An engineer can actually specify how material properties change according to a function or equation, and use that in combination with additive manufacturing. The idea here is you can have the material properties change according to a certain axis within your part. You could change it with multiple axes or perhaps even variant with respect to different equations or formula. For example, within certain constraints or within a certain geometric area, like a sphere, the material properties could be different than an outer one.

This is manifesting in a lot of different ways. You see 3D printers now with multi-material printing, where you have multiple materials within one component. We are quickly approaching the time when you could mix different powders that have different material properties. When you mix them, you get new composite material properties. Additive manufacturing is opening up a whole new world of capability there.

What does this mean for mechanical design? Well, alongside micro-geometry modeling, this is now another lever that mechanical engineers can pull to affect requirement satisfaction and performance issues. You have this same exact shape. You can vary the material properties along its length and its center. You can make it harder or softer. And dramatically affect how the exact same geometric shape has different performance properties, stiffness, deflection, and natural frequency. All these outcomes that you really care about when it comes to mechanical performance.

The Three Trends Impact on Mechanical Design

We have covered macro-geometry modeling, micro-geometry modeling, and material properties. Let’s talk about the implications of all these new advances. These three new capabilities really can have a drastic effect on mechanical design. With macro-geometry modeling, we talked about a new capability in generative design that will automatically produce new design suggestions and alternatives. If paired up with a voice assistant in augmented reality, then mechanical engineers could basically be leading a whole team of software agents. They’re doing a lot of the design exploration for the mechanical engineers.

Another lever that they can pull now is micro-geometry modeling. You could have the same exact shape, but you can have lattices and other types of mathematically defined geometry deliver dramatically different performance and requirement satisfaction. That is also true with the advances in material properties. Being able to specify how material properties vary spatially and geometrically can also let the mechanical engineer define how the same exact shape can have dramatically different performance, but with different materials. Big advances on all fronts and are positioned to dramatically affect how mechanical design looks like going forward.