Method and apparatus for determining the center position of a vehicular steering system
First Claim
Patent Images
1. An apparatus for determining the center position of a vehicular steering system, comprising:
- steering sensor means for sensing the position of said steering system with reference to a predetermined, but adjustable, center position and for defining two windows of operation of said steering system, said windows comprising a first relatively movable window which generally tracks the instantaneous position of said steering system and a second relatively fixed window having a location which is resettable only after at least one time dependent condition has been satisfied;
first timer means for determining the amount of time said steering system has been operated within said movable window, with said first timer means including means for nulling the time accumulated by said first timer means whenever said steering system is operated outside of said movable window;
second timer means for determining the amount of time said steering system has been operated within said fixed window, with said second timer means including means for suspending the accumulation of time by said second timer means whenever said steering system is operated outside of said fixed window; and
processor means for directing the placement of said predetermined center according to the accumulation of time by either of said timer means, with said processor means comprising positioning means for relocating the position of said predetermined center in the event that either of said timer means has accumulated time equal to a threshold period.
2 Assignments
0 Petitions
Accused Products
Abstract
A method and apparatus for determining a center position of the vehicular steering system includes a steering sensor and a control unit. A variable threshold time strategy is employed with a fixed window of operation and a movable window of operation to determine a precise center for the steering system. As an option, the control algorithm may employ both a variable theshold time and a variable size for the movable window of operation.
32 Citations
29 Claims
-
1. An apparatus for determining the center position of a vehicular steering system, comprising:
-
steering sensor means for sensing the position of said steering system with reference to a predetermined, but adjustable, center position and for defining two windows of operation of said steering system, said windows comprising a first relatively movable window which generally tracks the instantaneous position of said steering system and a second relatively fixed window having a location which is resettable only after at least one time dependent condition has been satisfied; first timer means for determining the amount of time said steering system has been operated within said movable window, with said first timer means including means for nulling the time accumulated by said first timer means whenever said steering system is operated outside of said movable window; second timer means for determining the amount of time said steering system has been operated within said fixed window, with said second timer means including means for suspending the accumulation of time by said second timer means whenever said steering system is operated outside of said fixed window; and processor means for directing the placement of said predetermined center according to the accumulation of time by either of said timer means, with said processor means comprising positioning means for relocating the position of said predetermined center in the event that either of said timer means has accumulated time equal to a threshold period. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. An apparatus for determining the center position of a vehicular steering system, comprising:
-
steering sensor means for sensing the position of said steering system with reference to a predetermined, but adjustable, center position and for defining two windows of operation of said steering system, said windows comprising a first relatively movable window which generally tracks the instantaneous position of said steering system and a second relatively fixed window having a location which is resettable only after at least one time dependent condition has been satisfied; first timer means for determining the amount of time said steering system has been operated within said first movable window, with said first timer means including means for nulling the time accumulated by said first timer means whenever said steering system is operated outside of said movable window; second timer means for determining the amount of time said steering system has been operated within said fixed window, said second timer means including means for suspending the accumulation of time by said second timer means whenever said steering system is operated outside of said fixed window; third timer means for determining the amount of time said steering system has been operated outside of said fixed window, with said third timer means including means for incrementing the accumulation of time by said third timer means whenever said steering system is operated to one side of said fixed window and for decrementing the accumulation of time by said third timer means whenever said steering system is operated to the other side of said fixed window; and processor means for directing the placement of said predetermined center and said windows according to the accumulation of time by each of said timer means, with said processor means comprising; positioning means for relocating the position of said predetermined center in the event that either said first or second timer means has accumulated time equal to a first threshold period or said third timer means has accumulated time equal to a second threshold period; means for changing the value of said first threshold period whenever the location of said predetermined center is adjusted; means for relocating said moving window about the instantaneous location of said steering system whenever said first timer means is nulled; and means for relocating said fixed window whenever the time accumulated by either of said first or second timer means is equal to said first threshold period. - View Dependent Claims (18, 19, 20)
-
-
21. A method for adjusting the center position of a vehicular steering system from a predetermined position to a new position, comprising the steps of:
-
defining two windows of operation of said steering system, said windows comprising a first relatively movable window having a location which generally tracks the instantaneous position of said steering system and a second relatively fixed window having a location which is resettable only after at least one time dependent condition has been satisfied; recording the amount of time said steering system is operated within said movable window, but nulling the accumulated time whenever said steering system is operated outside of said movable window; recording the amount of time said steering system is operated within said fixed window, but suspending the accumulation of time whenever said steering system is operated outside of said fixed window; and adjusting the position of said predetermined center to a new position whenever either of the recorded time values is equal to a first threshold period. - View Dependent Claims (22, 23, 24, 25, 26, 27, 28)
-
-
29. In a vehicle including a multistable suspension unit having a plurality of predetermined operating states and a power assisted steering mechanism, a system for determining the center position of a vehicular steering system, comprising:
-
steering sensor means for sensing the position of said steering system with reference to a predetermined, but adjustable, center position and for defining two windows of operation of said steering system, said windows comprising a first relatively movable window which generally tracks the instantaneous position of said steering system and a second relatively fixed window having a location which is resettable only after at least one time dependent condition has been satisfied; first timer means for determining the amount of time said steering system has been operated within said first movable window, with said first timer means including means for nulling the time accumulated by said first timer means whenever said steering system is operated outside of said movable window; second timer means for determining the amount of time said steering system has been operated within said fixed window, said second timer means including means for suspending the accumulation of time by said second timer means whenever said steering system is operated outside of said fixed window; third timer means for determining the amount of time said steering system has been operated outside of said fixed window, with said third timer means including means for incrementing the accumulation of time by said third timer means whenever said steering system is operated to one side of said fixed window and for decrementing the accumulation of time by said third timer means whenever said steering system is operated to the other side of said fixed window; and processor means for directing the placement of said predetermined center and said windows according to the accumulation of time by each of said timer means, with said processor means comprising; positioning means for relocating the position of said predetermined center in the event that either said first or second timer means has accumulated time equal to a first threshold period or said third timer means has accumulated time equal to a second threshold period; means for changing the value of said first threshold period whenever the location of said predetermined center is adjusted; means for relocating said moving window about the instantaneous location of said steering system whenever said first timer means is nulled; and means for relocating said fixed window whenever the time accumulated by either of said first or second timer means is equal to said first threshold period.
-
Specification