The beating of the eukaryotic flagellum, e.g. of the sperm cell, is powered by around 10,000 molecular motors (dyneins) acting on a parallel array of cytoskeletal filaments (microtubules). Regular bending waves traveling along the flagellum arise from a coordinated modulation, in space and time, of motor activity. We have developed a minimal molecular system in which polymerizing actin filaments in the presence of myosin motors self-assemble into beating filament bundles. The beating waveforms in this artificial system mimic those of eukaryotic flagella, despite the different identity of the filaments and motors at work. Wave-like beating thus appears to be a robust emergent property of motor-filament assemblies. Our system provides an avenue (i) to investigate the fundamental feedback mechanisms between filament bending and motor activity and (ii) for the bioengineering of novel motile systems. Originally, beating bundles were constrained to a thin 2D layer at the surface of a coverslip. Recently, we have established that bundles can also be grown from micro-beads, revealing helical 3D beating with chiral rotations. Here, we propose to further develop the 3D beating bundle assay, in particular to analyze how chirality at the single-filament scale is propagated to the mesoscopic scale of a whole bundle depending on motor type and on the organization of actin-filament network, and to find conditions where bundle beating may lead to persistent sperm-like swimming motion.