Abstract: A system uses multiple tilt sensors mounted to the vehicle frame and the vehicle suspension system to detect lateral acceleration and lateral load transfer. The system uses these measurements to determine a lateral load transfer ratio indicative of an actual roll moment compared to a maximum roll moment. The measurements from the tilt sensors are also used to calculate an effective center of gravity height. A display coupled to the system provides the vehicle operator with a read out of the load transfer ratio and effective center of gravity height. The display enables the vehicle operator to more completely understand the nature of the vehicle load and thereby allow the vehicle operator to avoid conditions likely to lead to a vehicle rollover accident.

Abstract: A digitally controlled valve system is composed of the main fluid control valve with a displaceable flow control portion (spool) that is controllably displaced by a digital pressure generator that generates digitally incremented pressure changes which operate against a biassing pressure or spring to displace the spool in a direct relationship to the pressure provided by the pressure generator. In one version, a main valve directs flow to either a high or a low pressure-control valve each of which is biassed toward a closed position by a pressure substantially equivalent to the pressure drop of flow of fluid through the main valve which pressure closes the valve stop flow when the pressure drop is too high (i.e. flow through the main valve is throttled). The flows through the valves are selectively adjusted via the digitally-generated pressure from the digital pressure generator.

Abstract: A modular digital actuator is formed by interconnecting a plurality of modules. Each of the modules includes a housing having a pair of different sized axially extending cylinder sections in which is received a T-shaped piston with the top of the T mating with the larger cylinder and the leg of the T forming a piston in the smaller cylinder. The leg of the T is hollow and forms a cylinder to receive an axially extending piston forming shaft to thereby provide three preferably different sized cooperating piston and cylinder areas, one formed in the cavity or hollows of the leg of the T, a second formed between the top of the T surrounding the leg of the T and the junction between the larger cylinder section and smaller cylinder section and the third formed in the smaller cylinder section between a closed free end of the smaller cylinder section and the leg of the T surrounding the piston forming shaft. The top of the T forms a piston wall in a fourth hydraulic cavity.

Abstract: A hydraulic actuator is formed by a first element incorporating a plurality of different sized piston cavities by a first set of piston elements which cooperate with a second set of piston elements and piston cavities respectively formed on a second element. Each of the cavities is selectively connected to a source of high pressure fluid or a source of low pressure fluid. The second element forms a driven piston in a cylinder formed by an extension of the first element. A second cylinder of a cross sectional area different from the first cylinder is hydrulically connected to the first cylinder and incorporates a second piston at its end remote from the first piston. The force or distance travelled by the second piston is correlated with that of the first or driven piston in a ratio equal to the ratio of the cross sectional areas of the two pistons. Preferably the second piston will be a double acting piston so that pressure may be applied to force the driven piston and first element together.

Abstract: A hydraulic actuator is formed by an assembly including a first element, a cylinder, a body section and a chamber. The first element is provided with a first set of a plurality of different sized piston cavities and piston elements which cooperate with a second set of piston elements and piston cavities respectively formed on a second element. The second element forms a piston in cylinder. The body sides incorporates, preferably in symmetrical relationship around the axis, of the assembly a plurality of valves, one valve for each of the pairs of cooperating pistons and cavities. A piston divides the chamber into a high pressure reservoir and a low pressure reservoir with the piston being urged toward the high pressure reservoir to maintain a difference in pressure between the high and low pressure reservoirs.

Abstract: A digital suspension for a wheeled vehicle incorporates digital hydraulic actuators at each wheel and includes a system for sensing lateral and longitudinal accelerations of a body portion of the vehicle and the position of each wheel relative to the body provides this information to a computer. The computer computes the forces required at each wheel and controls the digital hydraulic actuator at each wheel by adjusting in increments the force applied at each actuator between the wheel and the body to maintain the body portion of the vehicle in a substantially stable position.