Enhanced computer optimized adaptive suspension system and method

• US 6,502,837 B1
• Filed: 11/11/1999
• Issued: 01/07/2003
• Est. Priority Date: 11/11/1998
• Status: Expired due to Fees

• Current Assignee: Great Northern Technologies LLC, The Kenmar Company Trust
• Original Assignee: The Kenmar Company Trust
• Inventors: Hamilton, James M., Woods, Lonnie K.
• Primary Examiner(s): Culbreth, Eric
• Assistant Examiner(s): Dunn, David R.
• Application Number:
  US09/439,109
• Time in Patent Office: 1,153 Days
• Field of Search: 280/5.515, 280/5.503, 280/5.504, 280/5.505, 280/5.508, 280/5.51, 280/5.512, 280/5.5, 280/124.158, 280/124.159, 280/124.16, 280/124.161, 701/37, 701/38
• US Class Current: 280/5.515
• CPC Class Codes: B60G 17/0152 characterised by the action on a particular type of suspension unit B60G17/01941 takes precedence
• CPC Class Codes: B60G 17/018 characterised by the use of a specific signal treatment or control method
• CPC Class Codes: B60G 17/019 characterised by the type of sensor or the arrangement thereof B60G17/01941 takes precedence
• CPC Class Codes: B60G 17/0408 details, e.g. antifreeze for suspension fluid, pumps, retarding means per se
• CPC Class Codes: B60G 17/08 Characteristics of fluid dampers adjusting fluid dampers in general F16F9/44 - F16F9/53
• CPC Class Codes: B60G 2202/413 Hydraulic actuator
• CPC Class Codes: B60G 2202/416 using a pump, e.g. in the line connecting the lower chamber to the upper chamber of the actuator
• CPC Class Codes: B60G 2204/111 on pneumatic springs
• CPC Class Codes: B60G 2204/112 on dampers, e.g. fluid dampers
• CPC Class Codes: B60G 2206/41 Dampers
• CPC Class Codes: B60G 2400/102 vertical
• CPC Class Codes: B60G 2400/25 Stroke; Height; Displacement
• CPC Class Codes: B60G 2400/252 vertical
• CPC Class Codes: B60G 2401/26 Resistance type, e.g. as level indicator
• CPC Class Codes: B60G 2500/10 Damping action or damper
• CPC Class Codes: B60G 2600/184 Semi-Active control means
• CPC Class Codes: B60G 2800/012 Rolling condition
• CPC Class Codes: F15B 11/028 for controlling the actuating force F15B11/024 takes precedence
• CPC Class Codes: F15B 2211/40515 with variable throttles or orifices
• CPC Class Codes: F15B 2211/41536 being connected to multiple ports of an output member
• CPC Class Codes: F15B 2211/426 : electrically or electronically
• CPC Class Codes: F15B 2211/50572 : using a pressure compensating valve for controlling the pressure difference across a flow control valve
• CPC Class Codes: F15B 2211/526 : electrically or electronically
• CPC Class Codes: F15B 2211/6313 : the pressure being a load pressure
• CPC Class Codes: F15B 2211/6336 : representing a state of the output member, e.g. position, speed or acceleration
• CPC Class Codes: F15B 2211/6653 : Pressure control
• CPC Class Codes: F15B 2211/7053 : Double-acting output members
• CPC Class Codes: F16F 9/466 : Throttling control, i.e. regulation of flow passage geometry F16F9/464, F16F9/465 take precedence

Abstract

A system and method for controlling a damping system. The system has at least two dampers for damping between sprung and unsprung masses in the compression and rebound directions. Sensors generate signals based on position and other parameters of motion representative of the displacement between the sprung and unsprung masses. The process determines the appropriate compression and rebound forces to be applied at the wheels. A regulator responds to at least one of the independent compression and rebound control signals for adjusting, respectively, at least one of compression and rebound resisting forces of the dampers between the masses. Compliance for the dampers is emulated with software to produce the desired compliance forces. The distributed controller includes a processor that is responsive to signals representative of the position signals for forming the compression and rebound control signals for the regulator as a function of motion between the masses or a motion of a vehicle in which the dampers are located. The system has the capability of locking the suspension when parked.

Claims

1. A method of controlling one or more suspension control units, each suspension control unit comprising a body coupled to a damper shaft for damping between a sprung mass and an unsprung mass in compression and rebound directions, and at least one of a sensor for generating damper shaft position measurements, a sensor for generating steering angle measurements, a sensor for generating brake pressure measurements, a sensor for generating speed measurements and pressure regulators responsive to independent compression and rebound signals for adjusting, respectively, the compression and rebound forces imposed to the damper shaft through the suspension control unit, the method comprising:

receiving the measurement signals;

preconditioning the measurement signals to generate a plurality of preconditioning signals;

processing the preconditioning signals to determine one or more independent parameters for each of distinct states of motion;

determining, responsive to each independent parameter, for application to each suspension control unit, a desired independent response for each distinct state of motion;

generating compression and rebound control signals for each of the suspension control units from the desired independent response for each of the regulators; and

modifying the compression and rebound signals to account for an emulated compliance;

whereby application of each modified compression and rebound control signals to each wheel'"'"'s pressure regulator causes the forces imposed on each damper shaft to be modified.

2. A method of controlling one or more suspension control units, each suspension control unit comprising a body coupled to a damper shaft coupled to a wheel, and at least one sensor generating signals, the at least one sensor selected from the group of sensors consisting of sensors sensing damper shaft position, sensors sensing the degree of wheel turning, and sensors sensing brake application and sensing speed, the method comprising:

preconditioning the signals provided by the at least one sensor to generate a plurality of preconditioned signals;

processing the preconditioned signals to determine at least one independent parameter for each suspension control unit;

determining, in response to the at least one independent parameter, a desired independent response for each of a plurality of states of motion for each of the control units;

generating compression and rebound control signals for each of the suspension control units based on the desired independent response corresponding to each control unit;

modifying the compression and rebound control signals to account for vehicle loading conditions; and

providing the modified control signals to their corresponding control units, for causing the damper shaft of each control unit to apply damping force to its coupled wheel.

3. A method of controlling one or more suspension control units, each suspension control unit comprising a body coupled to a damper shaft coupled to a wheel, and at least one sensor generating signals, the at least one sensor selected from the group of sensors consisting of sensors sensing damper shaft position, sensors sensing the degree of wheel turning, and sensors sensing brake application and sensing speed, the method comprising:

preconditioning the signals provided by the at least one sensor to generate a plurality of preconditioned signals;

processing the preconditioned signals to determine at least one independent parameter for each suspension control unit;

determining, in response to the at least one independent parameter, a desired independent response for each of a plurality of states of motion for each of the control units;

generating compression and rebound control signals for each of the suspension control units based on the desired independent response corresponding to each control unit; and

modifying the compression and rebound signals, with a signal emulating compliance of an accumulator, wherein application of each modified compression and rebound control signal to each suspension control unit causes a force to be imposed on each damper shaft and to a wheel coupled to each damper shaft.

4. The method of controlling one or more suspension control units of claim 3 further comprising,

determining a wheel position; and

determining a force applied to a hydraulic actuator by multiplying the wheel position by a simulated spring constant.

5. A method for controlling one or more suspension control units of a vehicle, each suspension control unit comprising a body and an extensible member for damping between a sprung mass and an unsprung mass in compression and rebound directions, and a sensor for generating signals representative of the degree of the extension of the extensible member, the method comprising the step of:

receiving the signals;

processing the received signals to determine at least one independent parameter;

determining a filtered amplitude of a sprung natural frequency of the vehicle by filtering the received signals;

determining at least one of a plurality of parameters of motion in response to the at least one independent parameter, wherein one of the parameters of motion is a square root of a product of a displacement and the filtered amplitude at one or more selected frequencies;

determining, in response to each of said at least one independent parameter for each suspension control unit, a desired independent response for each of a plurality of states of motion; and

generating compression and rebound control signals for controlling each of the suspension control units in response to the desired independent response.

6. A method for controlling one or more suspension control units of a vehicle, each suspension control unit comprising a body and an extensible member for damping between a sprung mass and an unsprung mass in compression and rebound directions, and a sensor for generating signals representative of the degree of the extension of the extensible member, the method comprising the step of:

receiving the signals;

processing the received signals to determine at least one independent parameter;

determining a filtered amplitude of an unsprung natural frequency of the vehicle by filtering the received signals;

determining at least one of a plurality of parameters of motion in response to the at least one independent parameter, wherein one of the parameters of motion is a square root of a product of a velocity and the filtered amplitude at one or more selected frequencies;

determining, in response to each of said at least one independent parameter for each suspension control unit, a desired independent response for each of a plurality of states of motion; and

generating compression and rebound control signals for controlling each of the suspension control units in response to the desired independent response.