A steering mechanism comprising a first swing bar (1) with a first link (12) designed to allow the swing bar (1) to pivot about an axis of rotation (z). A second link (13) collaborates via a second pivot (23) with a first member (33) collaborating with a first wheel (43), and a third link (14) collaborates via a third pivot (24) with a second member (34) collaborating with a second wheel (44). The second link and the third link are positioned symmetrically. A fourth link (15) is designed to be able to collaborate via a fourth pivot (25) with a linear actuator (4). The fourth link is offset from said central axis so that actuation of the linear actuator (4) causes the swing bar to rotate, and causes a rotation of the wheels (43, 44).
