The retrofit problem: automated inspection of new models in the space you already have

When Volkswagen Slovakia prepared to build the new generation of the VW Passat and Škoda Superb at its Bratislava plant, the quality requirement was as demanding as it was unique: measure 14 different hang-on-parts, with the capacity to clear six complete bodies in a single eight-hour shift. If this was not difficult enough, another constraint loomed overhead: the solution that went in had to fit inside the existing footprint of 17 metres by 7 metres.

That second constraint is where a lot of good quality plans often run into trouble. The measurement requirement is as clear as day, but the available space to physically make it happen is not.

The retrofit squeeze

Introducing a new car model onto an existing site is rarely a blank-sheet exercise. The floor was laid out long before the new programme arrived. Tooling, robots and material flow already occupy the space. So when the new body panels need dimensional inspection, the question is not only how to measure them to the standards required. It is where the inspection is physically going to live, and how much production you are willing to lose while the necessary infrastructure is installed.

One option will always be a CMM, and for good reason. For a line designed from scratch, a fixed coordinate measuring machine in a controlled room is often exactly right. It will maintain accuracy that near-line scanning cannot always match.

However, a retrofit presents two issues this option can struggle with: space and time. A traditional setup needs a dedicated footprint, a stable environment, part handling to load and unload, and often a foundation to sit on. Finding all these requirements on an already occupied floor can be a non-starter. Building it means downtime the plant cannot risk. There is a more subtle cost too. When the part has to travel to an offline lab, every measurement carries a delay, and on a new model still settling in, that feedback lag is where scrap and rework can mount up.

Configured to fit, not forced to fit

This is the gap Hexagon’s PRESTO Quality Stations have been built to shore up. They are turnkey, modular inspection cells for medium-to-large components, designed to be configured around the constraints of a real site rather than to dictate a room of their own.

Volkswagen Slovakia’s solution shows what that looks like in practice. Rather than a single fixed machine, the cell was assembled by bringing together four rotary tables to cover the different part types. These included a Leica Absolute Tracker AT960 on a slider tracking an Absolute Scanner AS1 mounted on the robot, and an operating system running Hexagon Robotic Automation and PC-DMIS. That combination delivered best-in-class accuracy across 14 varied hang-on parts and the throughput of six bodies a shift. It did so inside the 17 by 7 metre space that was available. VW even required the robot arm itself to come from a specified external supplier, and this was easily integrated into the standard cell.

Modularity is what makes the footprint malleable. Built around a modular, scalable design, PRESTO can be configured to suit the available footprint, from space-constrained environments to larger installations. Its flexibility extends to sensor selection. This allows manufacturers to choose the optimal combination of accuracy, speed, and measurement capability for their specific application. You start with what fits the site and the budget you have now. The modular design then lets you scale the capability later rather than committing to a ten-year-fixed install on day one.

There is a skills point worth highlighting as well. A single quality specialist can build, test and deploy an inspection routine in hours, so absorbing a new model does not mean retraining the team on an unfamiliar workflows.

Why hang-on parts are key

The parts in this case explain why the fit had to be this precise. Hang-on parts such as tailgates and doors carry Class A surfaces that the customer sees and touches every day. They have to move, seal and align, and their geometries are awkward to measure. That combination demands both high accuracy and the flexibility to handle a range of very different parts on the same cell. Getting all of that into 17 by 7 metres, without a controlled metrology room to fall back on, is precisely the kind of problem the solution is designed for.

As Lenka Nováková, Head of the Body Shop Team in Segment 3 at Volkswagen Slovakia, put it: “We needed a highly reliable, accurate, and flexible solution to inspect the new models but had quite a stringent set of logistical criteria we had to stick to. We have worked with Hexagon in the past and they have been able to meet our needs this time as well.”

Where this leaves you for automated inspection

Automakers are under real pressure to work more quickly and more flexibly. Model cycles are shortening, capital budgets are tighter, and competition is pushing automakers to reduce development costs and become more agile without sacrificing quality. Ensuring quality processes are as close to production is one of the key ways to achieve this.

The retrofit problem means that while new models need measuring, the traditional way of measuring requires conditions a fast-moving, fully committed operation cannot easily give it.

PRESTO does not require those conditions. It brings automated inspection to the part, close to production and configured to the space that already exists, on a timeline that keeps pace with the programme.

Hexagon has worked with VW Group across many models and many years. This kind of long-term partnership is key when the goal is a repeatable solution rather than a one-off. Because PRESTO is a standardised quality station rather than a bespoke build, a configuration proven at one site can be deployed at the next. For a group like VW, and for Škoda within it, that is the real benefit. Quality solutions that scale globally across the group, with consistent global delivery and service backed by local support. And that means a new model launch does not mean reinventing the approach plant by plant.

Facing a new model with no floor space to spare? Download the PRESTO brochure or speak to a Hexagon expert about the configuration that fits your footprint.