Method and system for improved active damping of steering systems

• US 7,523,806 B2
• Filed: 09/20/2005
• Issued: 04/28/2009
• Est. Priority Date: 09/20/2005
• Status: Active Grant

• Current Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust), Steering Solutions IP Holding Corporation (Nexteer Automotive Group Ltd.)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Moeller, Bertram, Krieger, Geoff P., Pattok, Kathryn L., Kleinau, Julie A.
• Primary Examiner(s): Dickson; Paul N
• Assistant Examiner(s): ARCE, MARLON ALEXANDER
• Application Number:
  US11/230,889
• Publication Number:
  US 20070062755A1
• Time in Patent Office: 1,316 Days
• Field of Search: 701/41, 701/42, 180/446, 180/444, 180/443, 318/433, 318/434
• US Class Current: 180/446
• CPC Class Codes: B62D 5/0472 for damping vibrations

Abstract

A method for generating an active damping torque signal for a vehicle steering system includes receiving a vehicle speed input, receiving a handwheel velocity input, receiving a handwheel torque input, and generating an active damping torque output from each of the inputs, wherein the active damping torque output is non-linear with respect to the handwheel velocity input.

Claims

1. A method for generating an active damping torque signal for a vehicle steering system, the method comprising:

receiving a vehicle speed input;

receiving a handwheel velocity input;

receiving a handwheel torque input; and

generating an active damping torque output from each of said inputs, wherein said active damping torque output is non-linear with respect to said handwheel velocity input, and wherein said generating an active damping torque output further comprises;

generating a vehicle speed dependent damping value from said vehicle speed input;

generating a scaled handwheel velocity value using said handwheel velocity input and a nonlinear handwheel velocity dependent scale factor;

multiplying said vehicle speed dependent damping value with said scaled handwheel velocity value to produce an intermediate damping torque signal;

generating a handwheel dependent scaling factor from said handwheel torque input; and

multiplying said intermediate damping torque signal with said handwheel dependent scaling factor to result in said active damping torque output.

2. The method of claim 1, wherein said handwheel velocity dependent scale factor is zero below a first handwheel velocity value and unity above a second handwheel velocity value.

3. A method for generating an active damping torque signal for a vehicle steering system, the method comprising:

receiving a vehicle speed input;

receiving a handwheel velocity input;

receiving a handwheel torque input; and

generating an active damping torque output from each of said inputs, wherein said active damping torque output is non-linear with respect to said handwheel velocity input, and wherein said generating an active damping torque output further comprises;

generating at least a first damping torque value from said handwheel velocity value, based on a first vehicle speed;

generating at least a second damping torque value from said handwheel velocity value, based on a second vehicle speed;

blending said first and said second damping torque values, based on said vehicle speed input, to produce an intermediate damping torque signal;

generating a handwheel dependent scaling factor from said handwheel torque input; and

multiplying said intermediate damping torque signal with said handwheel dependent scaling factor to result in said active damping torque output.

4. The method of claim 3, wherein:

said first damping torque value is determined from a first curve, said first curve comprising a nonlinear, damping torque versus handwheel velocity curve that is configured for said first vehicle speed; and

said second damping torque value is determined from a second curve, said second curve comprising a nonlinear, damping torque versus handwheel velocity curve that is configured for said second vehicle speed.

5. A method for generating an active damping torque signal for a vehicle steering system, the method comprising:

receiving a vehicle speed input;

receiving a handwheel velocity input;

receiving a handwheel torque input; and

generating an active damping torque output from each of said inputs, wherein said active damping torque output is non-linear with respect to said handwheel velocity input, and wherein said generating an active damping torque output further comprises;

generating a plurality of damping torque values from said handwheel velocity value, based on a corresponding plurality of vehicle speeds;

linearly interpolating said plurality of damping torque values, based on said vehicle speed input, to produce an intermediate damping torque signal;

generating a handwheel dependent scaling factor from said handwheel torque input; and

multiplying said intermediate damping torque signal with said handwheel dependent scaling factor to result in said active damping torque output.

6. The method of claim 5, wherein said plurality of damping torque values is determined from a corresponding plurality of curves, each of which comprise a nonlinear, damping torque versus handwheel velocity curve that is specifically configured for a given one of said corresponding plurality of vehicle speeds.

7. A controller for generating an active damping torque signal for a vehicle steering system, comprising:

an algorithm configured for receiving a vehicle speed input, a handwheel velocity input, and a handwheel torque input;

said algorithm configured to generate an active damping torque output from each of said inputs, wherein said active damping torque output is non-linear with respect to said handwheel velocity input, and wherein said generating an active damping torque output flirt her comprises;

generating a vehicle speed dependent damping value from said vehicle speed input;

generating a scaled handwheel velocity value using said handwheel velocity input and a nonlinear handwheel velocity dependent scale factor;

multiplying said vehicle speed dependent damping value with said scaled handwheel velocity value to produce an intermediate damping torque signal;

generating a handwheel dependent scaling factor from said handwheel torque input; and

multiplying said intermediate damping torque signal with said handwheel dependent scaling factor to result in said active damping torque output.

8. The controller of claim 7, wherein said handwheel velocity dependent scale factor is zero below a first handwheel velocity value and unity above a second handwheel velocity value.

9. A controller for generating an active damping torque signal for a vehicle steering system, comprising:

an algorithm configured for receiving a vehicle speed input, a handwheel velocity input, and a handwheel torque input;

said algorithm configured to generate an active damping torque output from each of said inputs, wherein said active damping torque output is non-linear with respect to said handwheel velocity input, and wherein said generating an active damping torque output further comprises;

generating a first damping torque value from said handwheel velocity value, based on a first vehicle speed;

generating a second damping torque value from said handwheel velocity value, based on a second vehicle speed;

blending said first and said second damping torque values, based on said vehicle speed input, to produce an intermediate damping torque signal;

generating a handwheel dependent scaling factor from said handwheel torque input; and

multiplying said intermediate damping torque signal with said handwheel dependent scaling factor to result in said active damping torque output.

10. The controller of claim 9, wherein:

said first damping torque value is determined from a first curve, said first curve comprising a nonlinear, damping torque versus handwheel velocity curve that is configured for said first vehicle speed; and

said second damping torque value is determined from a second curve, said second curve comprising a nonlinear, damping torque versus handwheel velocity curve that is configured for said second vehicle speed.

11. A controller for generating an active damping torque signal for a vehicle steering system, comprising:

an algorithm configured for receiving a vehicle speed input, a handwheel velocity input, and a handwheel torque input;

said algorithm configured to generate an active damping torque output from each of said inputs, wherein said active damping torque output is non-linear with respect to said handwheel velocity input, and wherein said generating an active damping torque output flirt her comprises;

generating a plurality of damping torque values from said handwheel velocity value, based on a corresponding plurality of vehicle speeds;

linearly interpolating said plurality of damping torque values, based on said vehicle speed input, to produce an intermediate damping torque signal;

generating a handwheel dependent scaling factor from said handwheel torque input; and

multiplying said intermediate damping torque signal with said handwheel dependent scaling factor to result in said active damping torque output.

12. The controller of claim 11, wherein said plurality of damping torque values is determined from a corresponding plurality of curves, each of which comprise a nonlinear, damping torque versus handwheel velocity curve that is specifically configured for a given one of said corresponding plurality of vehicle speeds.