Most classic engineering joints are based on friction-reducing principles. Several biological joints however are using a different approach. The skeletal structure of the starfish for example allows the organism to maintain a constant body position without the use of external energy. This is achieved by a fascinating combination of small "bone like" structures (ossicles) which are embedded in a unique collagenous matrix.
One of the main goals of the BMBF-funded BIAG project is the analysis, development and construction of such bio-inspired joint structures for aerospace applications.