Patent US6. 85. 16. Simplifed adaptive suspension. BACKGROUND OF THE INVENTIONThis invention relates to an adaptive suspension system including a variable suspension member variable in response to steering input. Typically, an adaptive suspension system varies the dampening rate of a motor vehicle suspension system to provide optimal handling and comfort of passengers. A suspension system optimizes ride by transferring minimum disturbance to the vehicle body and thereby the occupants. To optimize vehicle handling during a cornering maneuver the suspension system must provide forces to compensate for the roll of the motor vehicle toward the outside of the turn. Air suspension is a type of vehicle suspension powered by an electric or engine-driven air pump or compressor. This compressor pumps the air into a flexible bellows. Design and Manufacture of an Adaptive Suspension System A Major Qualifying Project Report submitted to the faculty of WORCESTER POLYTECHNIC INSTITUTE. CLASS or Compressible Liquid Adaptive Suspension System provides a Luxury Ride with Sports Car Handling for large trucks, buses, ambulances and military applications. In an adaptive suspension system, the air suspension maintains the vehicle at a constant level on both axles independently of its load state. 3 Responses to “1984 – OSU ASV (Adaptive Suspension Vehicle) – Waldron & McGhee (American)” David Says: June 2nd, 2010 at 8:34 am. The OSU Adaptive Suspension Vehicle 1984. Machines That Walk The Adaptive Suspension VehicleMachines That Walk The Adaptive Suspension Vehicle PdfHowever, during straight line driving the same suspension system does not need to compensate for roll. In one known adaptable suspension system a strut that rotates with the steering mechanism changes dampening levels relative to the steering angle of the motor vehicle. This known system is impractical and limited in the range of dampening levels available due to the small steering angels experienced for most cornering maneuvers. Typically, in other adaptive suspension system the different dampening or roll rates required to optimize vehicle handling are attained by triggering a variable dampening member based on sensor input. Typically, a sensor or switch is triggered to change suspension characteristics. Such conventional systems vary the dampening or roll rate of the suspension dependent on inputs from sensors positioned throughout the motor vehicle. The sensors measure dynamic movements of the motor vehicle such as yaw, pitch, and roll. Typically, data gathered from the sensors is forwarded to an electronic control unit that in turn signals the suspension system such that appropriate changes can be made to optimize vehicle performance and handling. Typically, the sensors used to measure vehicle dynamics are costly, require delicate calibration, and are not feasible in production. Further, the use of sensors to measure vehicle dynamics introduces a lag time between movement of the vehicle, sensed movement and actual adjustment of the suspension system. A known adaptive suspension system includes a sensor placed on a steering column to sense steering position along with other sensors that measure lateral body acceleration in order to activate a variable stabilizer bar. Such a system still includes the complexities of costly lateral acceleration sensors that are not feasible in production. For these reasons, it is desirable to develop a suspension system that can vary the dampening rate depending on vehicle dynamics in a simple efficient and non- expensive manner. SUMMARY OF THE INVENTIONThe invention is an adaptive suspension system for a motor vehicle that varies to optimize vehicle handling in response to input from the steering system. This invention triggers an adaptive suspension system based on direct steering input by the operator. Sensing changes in the steering system directly discerns driver intent without the time delay encountered from the use of roll, yaw and pitch sensors. Further, the suspension system is optimized before the vehicle begins to roll or build up cornering forces. This is accomplished by sensing changes in hydraulic pressure within the steering systems hydraulic circuit. Detection of the steering column input is accomplished by sensors disposed within the hydraulic circuit of the steering system to measure pressure changes that indicating turning of the vehicle. Data from the sensors is forwarded to an electronic control unit (ECU) such that the ECU may make needed adjustments to the suspension system. The suspension system includes a wheel assembly suspended from the frame of the motor vehicle and at least one variable member. In one embodiment of the subject invention the variable member is a stabilizer bar having a variable length drop link. Actuation of the drop link changes the stiffness of the stabilizer bar to change the roll rate of the motor vehicle. In another embodiment of the invention, the variable member is a shock absorber having a variable dampening rate. In another embodiment of the invention, the variable member is hydraulically connected to the hydraulic system of the steering system such that sensors are not required. In this embodiment the stabilizer bar drop link or the variable dampening shock absorber are hydraulically connected to the hydraulic circuit of the steering system. The hydraulic connection may be direct such that hydraulic fluid flows from the steering system to the variable member, or indirect such that hydraulic fluid from the hydraulic circuit of the steering system triggers activation in a second hydraulic circuit to actuate the variable member. The suspension system of the subject invention provides the variable dampening characteristics required to optimize vehicle handling while eliminating the expense and lag time associated with the use of a plurality of external sensors. BRIEF DESCRIPTION OF THE DRAWINGSThe various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows: FIG. FIG. 1. A is a cross- sectional view of a hydraulic cylinder used to vary the stiffness of the stabilizer bar; FIG. FIG. 3 is a schematic drawing showing the variable stiffness stabilizer bar hydraulically connected to the hydraulic circuit of the power assist steering mechanism; FIG. A is a cross- section of the hydraulic cylinder including ports from the hydraulic system; FIG. FIG. 5 is a schematic drawing illustrating another embodiment of the variable stiffness stabilizer bar including a second hydraulic circuit; and. FIG. 6 is a schematic drawing illustrating another embodiment of the variable shock absorber including a second hydraulic circuit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTReferring to the Figures, wherein like numerals indicate like or corresponding parts throughout the several views or embodiments, the subject invention is an adaptive suspension system for a motor vehicle 1. FIG. The suspension system 1. Preferably the wheel assembly 1. A spindle arm 2. 2 is pivotally attached to each control arm 1. As appreciated, the specific configuration of the wheel assembly 1. A power steering system 2. The steering system 2. The steering system 2. The steering column 3. The valve 3. 4 includes input and output lines 3. The valve 3. 4 also includes left and right hydraulic lines 4. The power steering system 2. The operation of the power steering system 2. Further any type of power steering system 2. A sensor measures the steering position to determine if the motor vehicle 1. Preferably, a pressure sensor 4. The pressure sensor 4. Preferably, a pressure sensor 4. A worker knowledgeable in the art would understand that the position of the pressure sensor 4. Alternatively, a position sensor 5. A position sensor 5. A worker knowledgeable in the art will recognize that there are various locations on the steering system to locate a position sensor 5. The suspension system includes a variable dampening member. It should be understood that any variable dampening member that changes dampening as is known by a worker skilled in the art is within the contemplation of this invention. The variable dampening member shown in FIG. The stabilizer bar 5. Two arm sections 5. The drop links 5. In operation, as the motor vehicle 1. Varying the length of the drop link 5. Varying the roll rate of the motor vehicle 1. The stabilizer bar 5. The hydraulic cylinder 6. A, preferably, the hydraulic cylinder 6. In operation when the motor vehicle 1. Turning the steering column 3. The ECU 4. 6 will then signal activation of the hydraulic cylinder 6. Actuation of the hydraulic cylinder 6. It should be understood that the various known means of varying the dampening rate of a hydraulic cylinder are within the contemplation of this invention. Referring to FIG. The shock absorber 6. Further, the shock absorber 6. ECU 4. 6. In this embodiment the dampening rate of the shock absorber 6. The response is preferably measured by pressure sensors 4. In operation, the sensors 4. The input from the pressure sensors 4. ECU 4. 6. The ECU 4. Referring to FIG. Hydraulic communication between the steering system 2. Referring to FIG. In this embodiment the valve 3. The valve 3. 5 would communicate hydraulically with the hydraulic cylinders 7. It should be understood that any means of hydraulically communicating pressure from the steering system to the dampening member would be within the contemplation of this invention. Referring to FIGS. A, preferably the dampening member is a hydraulic cylinder 7. Preferably the hydraulic cylinder 7. Hydraulic pressure is ported to the upper and lower sections 7. In operation, during straight line driving, hydraulic pressure is substantially equal in the left and right hydraulic lines 4. Rotation of the steering column 3. Referring to FIG. As appreciated, the shock absorber 8. Alternatively, the shock absorber 8. The specific type of variable dampening rate shock absorber 8. Further, the term shock absorber as used in this application referrers to all struts, and shock absorber configurations as known in the art. Each shock absorber 8. Hydraulic communication between the hydraulic circuit 3. Referring to FIG. The valve 3. 5 in turn actuates the shock absorbers 8. It should be understood that any means of hydraulically communicating pressure from the steering system to the shock absorber 8. Referring to FIG. During straight line driving of the motor vehicle 1. Input into the steering system to initiate a turn creates a difference in pressure between the left and right hydraulic lines 4. The differential pressure triggers a change of dampening rate in the shock absorbers 8. The foregoing description is exemplary and not just a material specification.
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