The rotatable machine (1) of the invention comprises a chamber (2) and a shaft (3), wherein the shaft (3) is mounted in the chamber (2) such that, upon rotation of the shaft (3) and the chamber (2), the shaft (3) and the chamber (2) each rotate about the same axis (4), and a first motor (20) for driving the chamber (2) and a second motor (30) for driving the shaft (3), each motor (20, 30) having an axis, wherein the axes of the first and second motors (20, 30) and the axis (4) of rotation of the chamber (2) and of the shaft (3) are coincident.