Motor vehicle control

A vehicle having a chassis portion, a first suspension arrangement towards a first end of the vehicle and a second suspension arrangement towards an opposite end of the vehicle;

• the first suspension arrangement including a first left wheel laterally spaced from a first right wheel, each first wheel being connected to the chassis portion by at least one member such that the chassis portion can tilt;
• a tilt control arrangement including at least a tilt controller, a tilt motor and a tilt brake, the tilt motor and tilt brake each being operable to selectively apply a force or torque between the chassis portion and the at least one member of the first suspension arrangement;
• wherein
• the tilt controller has in use at least a first mode and a second mode,
• in the first mode of the tilt controller, the tilt control arrangement controls a tilt angle of the chassis portion using the tilt motor and/or the tilt brake,
• in the second mode of the tilt controller, the vehicle has a positive forward velocity or speed and the tilt controller does not control the tilt angle of the chassis portion for at least fifty percent of time the vehicle is operating with the tilt controller in the second mode;
• the tilt controller operating in the first mode when the vehicle is stationary or before the vehicle accelerates above a first minimum speed;
• when the tilt controller is operating in the first mode and the tilt motor is in use, the tilt motor adjusts the tilt angle of the chassis towards an unstable equilibrium position;
• the tilt controller selectively permitting a transition between the first mode and the second mode in dependence on at least one operating parameter of the vehicle;
• when the transition is from the first mode to the second mode, the at least one operating parameter includes vehicle speed and a signal indicative of an equilibrium state of the chassis portion, the controller selectively transitioning into the second mode when:
• the vehicle speed is greater than the first minimum speed;
• and/or
• the signal indicative of an equilibrium state of the chassis portion indicates unstable equilibrium.