Lane departure warning and change assist system utilizing active materials

• US 8,111,147 B2
• Filed: 05/13/2008
• Issued: 02/07/2012
• Est. Priority Date: 05/13/2008
• Status: Expired due to Fees

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Litkouhi, Bakhtiar Brian
• Primary Examiner(s): Lau, Hoi
• Application Number:
  US12/119,505
• Publication Number:
  US 20090284360A1
• Time in Patent Office: 1,365 Days
• Field of Search: 340/439, 340/426.31, 340/435, 340/438, 340/463, 340/465, 340/471, 340/903, 701/301, 701/96, 701/70, 701/23, 701/26, 701/41, 180/170, 180/443
• US Class Current: 340/439
• CPC Class Codes: B60Q 9/00 Arrangement or adaptation of signal devices not provided for in one of main groups B60Q1/00 - B60Q7/00 , e.g. haptic signalling
• CPC Class Codes: B60T 2201/082 using alarm actuation
• CPC Class Codes: B62D 15/025 Active steering aids, e.g. helping the driver by actively influencing the steering system after environment evaluation B62D1/28 takes precedence
• CPC Class Codes: B62D 15/029 Steering assistants using warnings or proposing actions to the driver without influencing the steering system

Abstract

A lane change assist and/or lane departure warning system adapted for use with a vehicle having a module engaged by an operator, wherein the vehicle travels within a lane, and the system includes a steering wheel sensor, at least one sensor operable to detect a lane-marking or an approaching object in adjacent lanes in the direction of host vehicle travel, a warning device including an active material element engaged with the module, and a controller communicatively coupled to the sensor and device and configured to determine a spatial relationship between the vehicle and the lane-marking or approaching object in the direction of host vehicle travel, compare the relationship to a threshold, transmit an activation signal to the element when the relationship exceeds the threshold or when an object is detected and the wheel sensor indicates a turn towards the object, and generate an alert by activating the element.

Claims

1. An active material based lane-departure warning system adapted for use by an operator and with a vehicle traveling within a lane delineated by at least one lane-marking, said system comprising:

at least one sensor operable to detect the location of the lane-marking relative to the vehicle;

a controller communicatively coupled to the sensor, and configured to execute a warning algorithm, wherein a spatial relationship between the vehicle and lane-marking is determined, the relationship is compared to a predetermined threshold, and an activation signal is caused by the controller to be generated when the threshold is exceeded; and

a warning device including an active material element operable to undergo a reversible change in property when exposed to or occluded from the activation signal, and communicatively coupled to the controller,

said device and controller being cooperatively configured to generate an alert as a result of the element being activated by the signal;

wherein the device includes an Magneto-Rheological Hydraulic Power Steering system, the element is Magneto-Rheological fluid housed and circulated within the MR-HPS system, and the device is configured to change the viscosity of the fluid when the signal is generated.

2. The system as claimed in claim 1, wherein the warning device and the change causes a haptic alert when the element is activated.

3. The system as claimed in claim 1, wherein the signal is an electric current and presents a profile having a modifiable amplitude and frequency, the device further includes a low current coil operable to generate a magnetic field when an electric current is passed therethrough, the controller is configured to cause the signal to pass through the coil when the threshold is exceeded, so as to generate the field, and the fluid engages and undergoes a reversible change caused by the field.

4. The system as claimed in claim 3, wherein the signal presents a trapezoidal profile having ramp up and down sections.

5. The system as claimed in claim 3, wherein the signal presents a periodic spike profile.

6. The system as claimed in claim 3, wherein the signal presents an initial dead-zone.

7. The system as claimed in claim 3, wherein the signal presents a stair stepped profile having an increasing amplitude.

8. The system as claimed in claim 1, further comprising:

an input device communicatively coupled and configured to transmit an input to the controller,

said controller being further configured to terminate the warning algorithm upon receipt of the input.

9. The system as claimed in claim 8, wherein the vehicle includes a braking module, and the input is the application of the braking module.

10. The system as claimed in claim 8, further comprising:

a timer communicatively coupled to the controller and configured to measure the passage of a period upon the generation of the alert,

said timer and controller being cooperatively configured to terminate the alert upon the passage of the period.

11. The system as claimed in claim 1, wherein said at least one sensor is a vision sensor including a camera and image processing unit.

12. The system as claimed in claim 1,

said spatial relationship being the time-to-lane-crossing (TTLC), as measured between the vehicle and lane-marking.

13. The system as claimed in claim 1, further comprising:

at least one condition sensor configured to determine a current vehicle or lane condition,

said controller being communicatively coupled to said at least one vehicle condition sensor, and further configured to modify the threshold based upon the condition.

14. The system as claimed in claim 13, further comprising:

a plurality of condition sensors including a steering angle sensor, an accelerometer, a GPS and map, and a wheel speed sensor.

15. An active material based lane change assist system adapted for use with a vehicle traveling within a lane and having a steering wheel, said system comprising:

at least one active or passive sensor operable to detect an object;

a first warning device including an active material element operable to undergo a reversible change in property when exposed to or occluded from an activation signal, wherein the change causes a haptic alert to be produced;

a steering wheel angle sensor operable to detect the direction of rotation of the wheel; and

a controller communicatively coupled to the active material element and steering wheel angle sensors and device, and configured to produce the activation signal, when the object is detected and the steering wheel sensor indicates rotation of the wheel towards the object, so as to cause the haptic alert to be produced;

wherein the device includes an Magneto-Rheological Hydraulic Power Steering system, the element is Magneto-Rheological fluid housed and circulated within the MR-HPS system, and the device is configured to change the viscosity of the fluid when the signal is generated.

16. The system as claimed in claim 15, further comprising:

a second warning device including a human-vehicle interface monitor and configured to selectively display a visible alert.

17. The system as claimed in claim 15, wherein said at least one active sensor is a lidar or radar device including a signal processing unit.

18. A method of alerting an operator of a vehicle to an impending improper lane change, wherein said vehicle includes a module engaged by the operator, said method comprising:

a. securing an active material element, operable to undergo a reversible change in property when exposed to or occluded from an activation signal, so as to be activated and deactivated respectively, relative to the module, such that a reversible characteristic of the element causes a module condition detectable by the operator;

b. determining the position of an approaching object in the direction of host vehicle travel in an adjacent lanes, or of a lane-marking, relative to the host vehicle, so as to determine a spatial relationship between the approaching object in the direction of host vehicle travel in adjacent lane, or the lane marking, and the host vehicle;

c. comparing the relationship to a threshold, generating an activation signal when the relationship exceeds the threshold, and transmitting the signal, so as to activate the element;

d. changing the characteristic by activating the element, and modifying the module condition by changing the characteristic; and

e. alerting the operator through the change in module condition; and

f. wherein the module includes an Magneto-Rheological Hydraulic Power Steering system, the element is Magneto-Rheological fluid housed and circulated within the MR-HPS system, and the module is configured to change the viscosity of the fluid when the signal is generated.