Digital assembly planning

The project is located in the field of digital assembly planning in vehicle construction. The long-term goal is the automatic generation of an assembly priority graph from which valid assembly sequences for a new vehicle can be derived. The most important basic component for an assembly priority graph is the so-called path planning: For a component in a given assembly situation, the (dis)assembly movement of the component must be calculated. The components of a vehicle are available as triangulated 3D CAD data. For small parts (e.g. screws, nuts or clips) and for rigid components (taking into account their cast-on and partially flexible fastening elements), the automated calculation of disassembly paths from the installed position in the vehicle to an assembly station outside the vehicle is explored and implemented.

The project is divided into two sub-projects. In the path planning for real-world (rigid) components, small parts (e.g. screws or nuts) and cast-on fastening elements (e.g. movable clips) play an important role, since components in their installed position, in the so-called near range, are always unavoidably in collision with their surrounding geometry due to them. In addition, they are often responsible for rotational movements during disassembly. The geometric algorithms we have developed for path planning in the near range take fastening elements into account during disassembly. No other academic or commercial software is currently able to do this. Other solutions simply allow some degree of penetration, which has been shown to lead to incorrect and therefore potentially invalid assembly paths, or ignore the problem completely.

For the path planning in the far range following the planning in the near range, geometric algorithms are developed to find suitable disassembly paths to the assembly stations. Here the focus is on translationally short paths with limited rotation, which guarantee a fast and easy assembly.