Mechanical system

The mechanical implementation of the Creuat Suspension System requires the linkages from each wheel to a central device. This layout requires a few chassis changes to accommodate the new connections, but it can provide the same advantages regarding the spring rate control on every body movements and freeing the axle crossing.

As in the general diagram, wheels are connected to resilient elements that transmit forces and movements to the central device. Such central device contains other spring elements that easily allow pitch movements to be stiffer than vertical movements. It also allows specific damping of pitch movements by incorporating extra dampers. This layout is specially suited for vehicles with a low roll inertia that have more demands on damping to pitch than to roll, which apply to most street cars.

CREUAT has developed a mechanical prototype that fits in a Nissan Terrano chassis.The system implements a central device that is connected to each wheel by means of torsion bars. The former suspension arrangement used similar torsion bars for the front suspension. Now, these four torsion bars (white) are responsible of the roll stiffness.

The central device (orange) provides the pitch and vertical softer resiliencies, and at the same time frees the axle crossing within a reasonable wheel travel. In this implementation, the pitch movement can be made stiffer than the vertical movement to increase handling properties without impairing comfort associated to the softer vertical movement.

This design has also the ability to incorporate two dampers in the central device (not seen in this prototype), so the pitch movement can be conveniently damped more than the vertical movement.

Mechanical solution key Benefits

Mechanical system layout

The mechanical solution can employ two different ways to connect the wheels movements to the central device:

Torsion bars
As in the prototype above, it would use wheel suspension arms that usually rotate along a longitudinal axis. Like in the prototype chassis many cars have longitudinally arranged torsion bars instead of other resilient elements such as coil springs or leaf springs . Like in the images above, these configurations can be rearranged to connect the wheel movements to the central device.
Connecting links
An alternative configuration uses connecting rods that transmit vertical wheel movements once have been transformed into longitudinal movements by means of angled levers. The central device is then similar to the above configuration, with some design variations to accommodate the transmission elements.