We are trying to use KUKA with pellets extruder, so we took the Universal Pellets Extruder of RichRap ( https://www.youmagine.com/designs/universal-pellet-extruder-reprap-3d-printing ) and created a holder to attach to KUKA flange. There are two differences from the original Richard's model: the placement "wings" are of no need, and the M4 bolts should be longer.