Exploring DfAM Alternatives - An Introduction to Grasshopper for Rhino

For many engineers, the choice of CAD system barely feels like a choice at all. Aerospace has its established platforms, as does automotive, medical device manufacturing, precision engineering and major OEMs. These environments are supported by decades of workflows, standards, training, and institutional knowledge. This is entirely understandable, but additive manufacturing raises an uncomfortable question. What happens when the geometry we want to engineer no longer fits comfortably inside the tools we traditionally use to engineer it?

That question is becoming more relevant as Design for Additive Manufacturing (DfAM) moves beyond familiar exercises in lightweighting and part consolidation. Engineers are increasingly exploring highly branched manifolds, spatially graded structures, conformal lattices, complex internal flow paths, and geometries the form of which responds directly to structural, thermal ,or fluid-flow data.

The manufacturing process may be capable of producing these forms, but increasingly, creating and iterating them is where the difficulty begins.

WHAT MAKES A CAD SYSTEM “GOOD”?

Traditional CAD is extraordinarily capable of creating precisely controlled mechanical components. Extrusions, revolves, holes, pockets, fillets, assemblies, and carefully dimensioned surfaces remain fundamental to engineering. DfAM does not invalidate any of this, but it does, however, introduce a different class of problem.

Consider a structure containing thousands of interconnected members, a manifold in which twenty channels must merge smoothly, or a component the wall thickness of which needs to vary continuously according to stress or temperature. These are not simply more complicated conventional parts, they are geometries whose form may need to be generated from engineering rules rather than constructed feature by feature.

At that point engineers do not need to know whether a CAD package is sufficiently powerful, but whether the design environment allows them to express the engineering problem they are actually trying to solve.

FROM DRAWING GEOMETRY TO GENERATING IT

Grasshopper, the visual programming environment built around Rhino, offers a different way of thinking. Instead of directly constructing every piece of geometry, designers create relationships between parameters, data, and form. Numbers can drive curves, curves can generate surfaces, simulation results can influence dimensions, and change an input and an entire model can respond. Geometry therefore becomes more than an object, it becomes the output of a definition.

For DfAM, this is a profound shift. Imagine hundreds of lattice members the dimensions of which need to respond to their position within a component. Managing that variation manually quickly becomes impractical. In a computational workflow, the rule governing the variation can instead become part of the model, change the requirement and the geometry follows.

The same principle can apply to internal channels, cellular structures, heat-transfer surfaces, repeated features, and almost any geometry that can be described through relationships. The engineering intelligence sits not only in the final CAD file, but in the logic that produced it, and that makes it possible to move from creating individual design variants towards exploring entire design spaces.

WHEN THE WORKFLOW RUNS OUT OF ROAD

But this exposes a further challenge. Generating sophisticated geometry computationally is one thing, turning increasingly complex definitions into robust, editable solids can be another. Highly interconnected lattices, thousands of blended junctions, graded forms, and intricate manifolds can place significant demands on conventional modelling methods. Imported meshes and scan data introduce another layer of complexity.

Implicit and voxel-based modelling provide powerful alternatives. Implicit geometry represents form mathematically rather than building it from huge numbers of individual surfaces. Voxel methods allow complex forms, meshes, and measured geometry to be smoothed, repaired, and reshaped in different ways.

These methods are already well established, but the more interesting issue is where they sit in the workflow. If a computational designer generates a promising geometry in Grasshopper but must export it into another specialist environment to complete it, something important can be broken. The geometry survives, but the parametric relationship that created it may not.

That makes iteration harder. Engineering intent and final geometry can begin to separate, and a significant design change may require stepping backwards through the workflow, regenerating the model, exporting again, and repeating downstream processing.

That is one of the problems we have been exploring at Metamorphic, and it is also the reason we developed Morphé.

KEEPING ADVANCED GEOMETRY COMPUTATIONAL

Morphé is a new Grasshopper plugin developed by Metamorphic to bring implicit modelling, voxel processing, and vector-field capability directly into the environment where computational geometry is already being generated. The important point is not simply what Morphé does, it is where it does it.

By working inside Grasshopper, advanced geometry can remain connected to the rules, parameters, optimisation processes, simulation data, and engineering intent that created it.

A designer can generate a complex manifold parametrically, smooth selected regions using voxel methods, allow simulation data to influence its form, and continue developing the geometry without turning the process into a disconnected sequence of software hand-offs.

Likewise, the aim with lattices is not simply to provide another catalogue of predetermined cells. A library gives engineers answers, whereas a genuinely computational environment should give them the means to formulate their own.

Morphé allows structures to be generated from curves, surfaces, or mathematical definitions, varied spatially and connected to the wider Grasshopper definition. Not every useful engineering form begins with a clean mathematical description either. Scan data, meshes, and experimentally derived geometry also need to participate in advanced design workflows. Voxel methods create another route for manipulating these inputs without forcing them into an inappropriate modelling paradigm.

The opportunity is therefore not implicit versus voxel modelling, it’s allowing different representations to do what they do best without each transition becoming a dead end.

WHY THIS MATTERS

There is a broader engineering argument behind all this. As design becomes more computational, the goal should not be complexity for its own sake, it should be geometry that earns its complexity through function.

Stress, temperature, pressure, flow, measured data, or optimisation results should be able to influence geometry where doing so creates a better engineering outcome, and the faster an engineer can see the consequence of a decision, the more alternatives can realistically be explored before resources are committed to manufacture.

This is where advanced modelling becomes commercially significant. The benefit is not simply saving modelling time, it’s increasing the probability that the geometry arriving at manufacture is the right geometry in the first place. Morphé grew from precisely these kinds of challenges through Metamorphic’s work in demanding areas including quantum technologies, bioprocessing, and optomechanical systems.

It was an engineering tool before it became a product, so the capability was developed because real projects demanded geometry that existing workflows made unnecessarily difficult to create, manipulate, or refine.

ACCESSIBILITY WITHOUT SIMPLIFICATION

Another part of the opportunity is accessibility. Advanced computational design has often required specialist platforms, deep programming expertise, or expensive enterprise software. Grasshopper already lowers part of that barrier through visual programming, and Morphé aims to extend this idea by bringing more advanced solid-modelling capability into an environment that many computational designers already understand.

That does not make sophisticated engineering trivial, and nor should it. Democratising advanced design should not mean simplifying the engineering, but instead mean removing unnecessary barriers between engineers and the problems they want to explore.

NOT REPLACING CONVENTIONAL CAD

None of this suggests established CAD platforms are becoming obsolete. Traditional CAD will remain indispensable for assemblies, interfaces, engineering drawings, dimensioning, and huge amounts of everyday mechanical design. The opportunity is to stop treating the choice as binary. The future of DfAM is likely to involve increasingly connected toolchains in which conventional CAD, computational design, simulation, optimisation, implicit modelling, and manufacturing software each perform the tasks they are best suited to.

For some geometries, conventional modelling will remain the obvious answer. for others, continuing to force an unfamiliar engineering problem through a familiar workflow may simply constrain what engineers are able to discover. Grasshopper encourages a subtle but important shift in thinking, moving from how do I model this shape to what rules, data and engineering requirements should generate this shape?”

Morphé takes that argument one step further. What happens when the advanced modelling capability required to realise that geometry no longer sits downstream from the computational process, but inside it? This is the question we have been working on, and very shortly, we will be showing the engineering community our answer.

Watch this space. Morphé is coming. Soon!