Working from CAD: what device companies should know before commissioning animation

Yes, a device animation should be built from your CAD — and no, the CAD will not be used directly. Engineering models are built to manufacture from, which means they carry tolerances, internal geometry, fasteners and assembly detail that is invisible on screen and expensive to render. A model with millions of polygons describing threads nobody will ever see slows every stage of production without improving a single frame. So the CAD is used as the source of truth for geometry and proportion, then rebuilt at a density suited to animation. That rebuild is normal, expected, and is what makes the device on screen genuinely your device rather than an approximation — while keeping the project renderable. What you send, and in what format, has a direct effect on how long this takes.

What to send

STEP is the most useful general format for animation work, and most CAD packages export it. Native formats are also fine if the studio can open them. Meshes such as STL work but lose the clean surfaces that make a device look manufactured rather than melted.

Alongside the geometry, the genuinely useful extras are:

• An assembly, not just parts — how the components relate matters more than any single one
• Materials and finishes, even informally. “Anodised aluminium, matte” saves a round of guessing
• Anything that moves, and its range. This is what the animation is for, and it is rarely obvious from the model
• Anatomical context if placement matters — which vessel, which approach, what size relative to what

The two things that cause delays

Model revisions mid-project. Devices under development change. If a design change lands after animation has begun, the affected shots are rebuilt. Not catastrophic if flagged early, expensive if discovered at render. Tell the studio if a revision is expected, and when.

Confidentiality logistics. Most device animation involves unreleased product, so an NDA is routine and worth sorting before the first file transfer rather than after. Ask how the studio stores and transmits your files; a serious answer exists.

What the animation should show that a render cannot

A photograph or a static render shows what the device is. Animation shows what it does: deployment, actuation, seating, how it interacts with tissue, and what the clinician sees at each moment. If a still could carry the message, the animation is being asked to do decoration rather than work.

The other thing worth deciding early is who reviews it. Device animation typically passes marketing, regulatory, clinical and sometimes a surgeon advisory board. That breadth is why these projects run longer than their runtime suggests, and why consolidating comments per stage matters more here than anywhere else.

More on how these are built on the medical device animation page.