Although not strictly a vane-type engine, a 2000 design
by Saint-Hilaire et al. shows a four bar mechanism
incorporated to position pivoting blades with the bars
acting as an articulating rotor face [46]. The
quasiturbine rotary engine utilizes four carriages that
support the pivots of a variable-shape four-element
rotor. The rotor moves along the inner face of a stator
with an oval shape. The movement has the rotor
components align alternatively in an oval square
arrangement. The four cycle system has a compression
ratio that is a function of the diagonal ratio