Bambu Lab receives patent for algorithm for automatic material allocation in multi-material 3D printers

The Chinese company Bambu Lab has been granted a new patent for a process that is designed to make filament changes in multi-material 3D printers significantly more efficient. Published under the number WO-2025218693-A1, the patent describes a method that relies not on new hardware, but on intelligent software logic for material allocation.

In conventional FFF 3D printing with only one extruder, material management is simple—one filament, one print head. It becomes more complex when multiple extruders and automatic material changers (AMS) are combined. In such cases, the system must decide which material is assigned to which print head in order to minimize the number of changeovers and material loss due to cleaning processes.

Bambu Lab’s patent describes an algorithmic solution for this. A so-called co-occurrence matrix analyzes how often certain colors or materials occur in the same layers of a model. Based on this data, an algorithm groups the materials so that filaments that are rarely used together are assigned to the same print head. This reduces the need for filament changes while also minimizing material loss during nozzle flushing.

The technology is likely to be particularly relevant for upcoming Bambu Lab systems such as the “Vortek” model, which, according to earlier announcements, will be equipped with up to seven hot ends and two print heads. Without automated assignment, manual planning of such a multi-material setup would be hardly practical.

For competitors such as Prusa Research or Snapmaker, the patent could mean strategic restrictions. Both companies are developing their own multicolor systems, some of which are based on fixed extruders or modular tool heads. If they want to use similar material changers in the future, they would have to resort to alternative methods or enter into licensing agreements with Bambu Lab.