Definition: A virtual prototype is a digital model of a product that is not built yet, or not built in this form yet. It comes from the CAD data of the design. You use it to check form, function, assembly and operation before a physical sample is made. Depending on the question, it is a pure visualization model or it is combined with simulations (kinematics, strength, flow).

In B2B mechanical engineering, virtual prototypes are used for: design reviews with engineering, production and service, installation space and collision checks, ergonomics checks at the operator station, alignment with customers before approval, and early sales material for trade shows and quotes.

Advantage: You find errors while they only cost a CAD change, and not on the built sample.

English: Virtual Prototype, Digital Prototype
German: Virtueller Prototyp, digitaler Prototyp, Digital Mock-up (DMU)

How It Works

From the CAD model to the review model

CAD data is made for design, not for presentation. For a review in real-time 3D, the model goes through several steps of the 3D pipeline:

  1. Export: The assembly comes from the CAD system, often through neutral formats such as STEP or JT.
  2. Tessellation: Mathematical surfaces are converted into triangle meshes.
  3. Simplification: Internal parts, standard parts and holes are reduced or removed, depending on the purpose.
  4. Preparation: Materials, the assembly structure and animations (for example doors, axes, lifting units) are added.
  5. Delivery: The model runs in a web viewer, a kiosk application, or an AR or VR environment.

One model, several output channels

Platform Strength in the review Limitation
Web viewer No installation, a link for all participants Limited sense of size
Kiosk, large screen Joint review in the meeting room Fixed location
AR (tablet, headset) Machine at full size in the real hall Tracking and lighting conditions on site
VR Walkable 1:1 scale, test the operation Headset and introduction necessary

You can answer many questions on the screen. AR and VR show their strength when scale, reachability and space requirements are the topic.

B2B Applications

Design review

Engineering, production, service and sales look at the same model. Typical questions: Can the technician reach the filter? Does the machine fit through the hall door? Can the operator reach the emergency stop from the operating position? In VR, you can check this at full size, and in mixed reality also directly at the planned installation site.

Fewer physical prototypes

Physical samples stay necessary for function tests, approval and endurance runs. But a virtual prototype can replace intermediate versions that are only used to align form and layout. This saves material, production time and transport to alignment meetings.

Production and assembly planning

On the virtual prototype, production checks in which order assemblies are installed, whether tools reach all screw connections and how large parts are transported. You can also prepare the installation at the customer site: foundation, connections, maintenance areas and escape routes are checked in the hall layout, for example with scan data from LiDAR recordings.

Sales and trade shows

The virtual prototype is often the first image of a new product line. With it, sales and marketing can prepare quotes, product pages and trade show presence before the first machine is finished. At the trade show, a kiosk or an AR model shows the new machine, even when it is too large for the booth or not available yet.

Customer alignment

For special-purpose machines, the customer checks the layout and variants before approval. Change requests come up in the design phase instead of during commissioning. A link to the web viewer is sufficient, so that purchasing, production and occupational safety at the customer can look at the model at the same time, without installing software. Comments and questions from these rounds go directly into the next design version, and you can track them in the next review.

Service and training

Maintenance instructions and training content come from the same model. Service technicians and operators get to know the machine before it is delivered.

Difference from the Digital Twin

People often mix up the terms, but they describe different phases:

Feature Virtual prototype Digital twin
Phase Development, before construction Operation, after commissioning
Reference A design or a product line A specific, real system
Data CAD, simulation, assumptions Live data from sensors and IoT systems
Goal Check and improve the design Monitor the condition, plan maintenance, optimize operation

Connection: The virtual prototype is often the starting point for the later digital twin. The geometry stays, and the connection to the operating data of the real machine is added.

Challenges

Data preparation

Large systems have many thousands of parts. An unprocessed CAD export is usually too heavy for a browser, tablet or headset. Without targeted simplification, the loading time and frame rate suffer, and with them the acceptance in the review.

Currency

Design versions change all the time. A review on an outdated model leads to wrong decisions. For this reason, clear versions and a repeatable preparation process are more important than a model that is perfect once.

Validity

A virtual prototype shows what was modeled. Cables, hoses, tolerances or deformations are often missing. Participants must know which questions the model can answer and which still need a real sample.

Organization

The benefit only comes when production, service and sales are involved early. For this reason, reviews need fixed dates in the development process, a moderator and documented results.

Frequently Asked Questions (FAQ)

Does a virtual prototype fully replace the physical prototype?

No. For proof of function, endurance tests, safety tests and certification, you still need real samples. The virtual prototype mainly reduces intermediate versions and moves troubleshooting to an earlier phase.

Which data do you need for a virtual prototype?

The basis is the CAD data of the assembly. For a convincing display, you add materials and colors, the assembly structure and, where useful, motion sequences. You can remove confidential details such as internal parts or production information before you share the model.

Is VR necessary for a design review?

Not always. Many alignments work in the web viewer or on a large screen. VR is worth it when you want to assess scale, lines of sight and reachability. AR is suitable to show the machine in the real environment.

How current does the virtual prototype stay?

That depends on the process. When the preparation is automated, you can deliver each new design version again with little effort. With manual preparation, it is a good idea to link reviews to defined milestones.

How is CAD data protected during the review?

Instead of the original CAD data, you share a tessellated, simplified model that cannot easily be converted back into design data. In addition, there are access rights and approvals, see data security.

Industry Standards and Technologies

Basics: - 3D model – geometry and structure - 3D pipeline – from CAD to the real-time model - Real-time rendering – display in real time - Reverse engineering – from the real part to the model - Digital mock-up (DMU) – complete digital model of a product

Platforms: - Virtual reality – review at 1:1 scale - Augmented reality – model in the real hall - Mixed reality – connection of reality and model - Extended reality (XR) – umbrella term - WebGL – 3D in the browser

Operation and data: - Digital twin – digital image of the real system - IoT – connected machines - Data security – protection of design data - Simulation – calculation of function and strength

Applications: - 3D product configurators – show variants early - Immersive experience – presentation at trade shows - Design review – joint check of the design - Virtual commissioning – test the control system on the model