Hand wheel position detection system

• US 9,254,869 B2
• Filed: 07/20/2012
• Issued: 02/09/2016
• Est. Priority Date: 12/23/2011
• Status: Active Grant

• Current Assignee: Steering Solutions IP Holding Corporation (Nexteer Automotive Group Ltd.)
• Original Assignee: Steering Solutions IP Holding Corporation (Nexteer Automotive Group Ltd.)
• Inventors: Ryne, Zaki, Kidder, Keith A., Sebastian, Tomy, Tarum, Carl D., Fisher, Paul M., Blehm, Scott T., Ross, Christian E.
• Primary Examiner(s): Olszewski, John R
• Assistant Examiner(s): CASS, JEAN PAUL
• Application Number:
  US13/554,017
• Publication Number:
  US 20130166141A1
• Time in Patent Office: 1,299 Days
• Field of Search: 701/34, 324/76.77, 324/141, 324/166
• US Class Current: 1/1
• CPC Class Codes: B62D 15/0215 by measuring on the steering column
• CPC Class Codes: B62D 15/0245 Means or methods for determination of the central position of the steering system, e.g. straight ahead position
• CPC Class Codes: G01D 3/0365 the undesired influence being measured using a separate sensor, which produces an influence related signal
• CPC Class Codes: G01D 5/145 influenced by the relative movement between the Hall device and magnetic fields see G01R33/06

Abstract

A steering system for detecting a hand wheel position is provided and includes an input shaft connected to a hand wheel, a main gear disposed around the input shaft, a puck gear meshingly engaged with the main gear, and a control module. The control module receives an angular main position of the main gear and an angular puck position of the puck gear. The control module includes a rotational calculation module for calculating the hand wheel position based on at least the angular main position and the angular puck position.

Claims

1. A steering system for detecting a hand wheel position, comprising:

an input shaft connected to a hand wheel;

a main gear disposed around the input shaft;

a puck gear meshingly engaged with the main gear; and

a control module, implemented in a hardware processor, for;

receiving an angular main position of the main gear and an angular puck position of the puck gear;

setting an empirical value equal to c₁- 1/G c₂, wherein c₁ is the angular main position, c₂ is the angular puck position, an G is the gear ratio;

finding a number of rotations of the input a number of rotations of the puck gear using the empirical value;

calculating a first hand wheel position based on the number of rotations of the input shaft;

calculating a second hand wheel position based on the number of rotations of the puck gear; and

determining that the first hand wheel position is incorrect if a difference between the first hand wheel position and the second wheel position is above a threshold value.

2. The steering system as recited in claim 1, wherein the control module uses equations:

c₁=α

−

360n₁, c₂ =G α

−

360n₂, and α

=c₁+360n₁, wherein α

is the hand wheel position, n₁ is a number of rotations of the input shaft, and n₂ is a number of rotations of the puck gear.

3. The steering system as recited in claim 2, empirical values computed by the term [c₁- 1/G c₂] differ from one another by at least thirty degrees depending on the angular main position c₁, the angular puck position c₂, the hand wheel position α

, the number of rotations of the input shaft n₁, and the number of rotations of the puck gear n₂.

4. The steering system as recited in claim 1, wherein a position of the main gear and a position of the puck gear are aligned generally at zero degrees.

5. The steering system as recited in claim 1, wherein a position of the main gear and a position of the puck gear are offset from zero degrees.

6. The steering system as recited in claim 5, wherein the control module is further configured for executing an alignment algorithm for adjusting the position of the main gear and the position of the puck gear.

7. The steering system as recited in claim 1, wherein the control module is further for finding a number of rotations of the puck gear using the empirical value.

8. The steering system as recited in claim 1, wherein the control module calculates the second hand wheel position using an equation:

α

′

=(c₂ +360n₂)/G, wherein α

′

is the second hand wheel position, and n₂ is a number of rotations of the puck gear.

9. A steering system for detecting a hand wheel position, comprising:

an input shaft connected to a hand wheel;

a main gear disposed around the input shaft;

a puck gear meshingly engaged with the main gear; and

a control module, implemented in a hardware processor, for;

receiving an angular main position of the main gear and an angular puck position of the puck gear;

setting an empirical value equal to c₁- 1/G c₂ wherein c₁ is the angular main position, c₂ is the angular puck position, α

is the hand wheel position, an G is the gear ratio;

finding a number of rotations of the input shaft from a lookup table saved in a memory of the control module using the empirical value; and

calculating the hand wheel position based on the number of rotations of the input shaft,

wherein the hand wheel position is related to the angular main position and the angular puck position by;

c₁ =α

- 360n 1, c₂=G α

- 360n₂, and α

=c₁ +360n₁, wherein α

is the hand wheel position, n₁ is the number of rotations of the input shaft, and n₂ is a number of rotations of the puck gear.

10. The steering system as recited in claim 9, wherein empirical values computed by the result of c₁- 1/G c₂ differ from one another by at least thirty degrees depending on the angular main position c₁, the angular puck position c₂, the hand wheel position α

, the number of rotations of the input shaft n₁, and the number of rotations of the puck gear n₂.

11. The steering system as recited in claim 9, wherein a position of the main gear and a position of the puck gear are aligned generally at zero degrees.

12. The steering system as recited in claim 9, wherein a position of the main gear and a position of the puck gear are offset from zero degrees.

13. The steering system as recited in claim 12, wherein the control module is further configured for executing an alignment algorithm for adjusting the position of the main gear and the position of the puck gear.

14. The steering system as recited in claim 9, wherein the control module is further for finding a number of rotations of the puck gear from the lookup table using the empirical value, and wherein the second hand wheel position is calculated by using an equation:

α

′

=(c₂ +360n₂)/G

wherein α

′

is the second hand wheel position.