Underbody panels (UBPs) are often installed in overhead positions or while workers maintain strenuous postures underneath the vehicle, placing significant strain on the shoulders, neck, and back. Large, flexible components with complex geometries also require considerable physical effort to position correctly. Fastening typically involves clips or screws that must first be picked up and carried, rather than being readily available. Particularly large components may require a second worker during screw fastening, and the available workspace is not always generous. At first glance, these factors seem to make a strong case for automation. Unfortunately, the situation is not quite that simple.

Underbody Panels: A Unique Challenge for Automation

Humans possess capabilities that technology still cannot easily replicate. Workers can position components accurately without relying on sensors or stopping the production line. They can also adapt flexibly to timing variations and do not need a rigidly assigned time slot within a cycle for a specific task. Soft, highly flexible components (technically referred to as limp or non-rigid parts) can be handled and transported with ease. Variations between parts rarely present significant challenges for workers when gripping, positioning, or fastening them.

For automated systems, however, the combination of positioning, fixing, and fastening often consumes considerable time. If a clip fails to engage correctly on the first attempt, rework is typically required – yet production cycle times leave little room for such corrections. Another challenge lies in the bulky, cumbersome, and sometimes difficult-to-stack components, whose substantial space requirements further limit options for automated handling. Moreover, product updates during a vehicle’s lifecycle generally increase the number of variants, meaning that a growing variety of parts must be accommodated within a single assembly cycle over the product’s lifetime. Specialized tooling for these variants would have to be manufactured in large quantities and potentially modified or replaced after relatively short periods.

A Practical Starting Point: One Vehicle Model, One Component, One Flexible Assembly Solution

At an early stage, the project team selected a specific component from the Volkswagen ID.3. Out of the 13 underbody panel components, a shielding component designed to improve vehicle aerodynamics emerged as the preferred candidate. Such components are often modified during a model’s lifecycle, making it useful to incorporate the challenge of sequential product variation into the research. The experimental setup employs handling robots and screw-driving robots as a flexible automation solution. Vacuum grippers pick up the component at three defined points to minimize deformation of the polypropylene part, which measures 110 cm in length, 88 cm in width, and only 2 mm in thickness, resulting in very low inherent stiffness. A screw-driving robot identifies the correct hole through which each screw must be inserted, guides the screws into position, and tightens them automatically. This automated subprocess could be integrated into an otherwise manual assembly process, creating a hybrid autonomous assembly solution.

The insights gained from installing this component are being used to improve the automation readiness of future generations of components and manufacturing processes.