Method & system for improving the driving behavior of a vehicle

• US 20060273657A1
• Filed: 04/28/2006
• Published: 12/07/2006
• Est. Priority Date: 10/28/2003
• Status: Active Grant

• Current Assignee: Continental Teves AG & Co. OHG (Continental AG)
• Original Assignee: Continental Teves AG & Co. OHG (Continental AG)
• Inventors: Pank, Matthias, Konanz, Jochen, Wickenhofer, Thorsten, Herrmann, Torsten, Roszyk, Mario, Wanke, Peter
• Granted Patent: US 7,681,960 B2
• Time in Patent Office: Days
• US Class Current: 303/146
• CPC Class Codes: B60T 2201/09 Engine drag compensation
• CPC Class Codes: B60T 2250/06 Sensor zero-point adjustment; Offset compensation
• CPC Class Codes: B60T 8/17555 specially adapted for enhancing driver or passenger comfort, e.g. soft intervention or pre-actuation strategies

Abstract

A method for a Sensitive Electronic Stability Program (SESP) presents a general approach for the correction of maneuvers of turning into a bend at low speed. It integrates existing methods as well as subsequent extensions. SESP supplements the standard active yaw control (AYC) function. This allows the SESP to use variables and mechanisms of AYC, on the one hand. On the other hand, AYC continues operating unimpeded in the background and will intervene as usual when SESP cannot stabilize the vehicle appropriately. When the standard AYC intervenes, SESP control operations are forbidden, or running SESP control operations are stopped. This stop can take place either abruptly or (which is more comfortable) by way of a moderate decrease of the correcting variables.

Claims

1. A driving situation detection system for observing and analyzing driving situations of a vehicle, at least including the situations of straight travel and cornering,

wherein the system is capable of observing and analyzing driving situations with almost steady-state courses of the vehicle at a steering angle velocity of lower than, or equal to, 120°

/s, wherein the system is designed as a state machine capable of detecting at least one of the states which are members of the group consisting of straight travel with partial braking, cornering with partial braking, and cornering with a change of load; and

wherein the system is capable of activating a controller depending on the states which reflect a course deviation.

2. The driving situation detection system as claimed in claim 1,

wherein it is connected to a reference signal model in which a YTC reference variable with an offset is corrected by means of an offset value, wherin the driving situation detection system determines the time at which the offset correction is started and terminated, and the offset value is superposed on the reference variable at the starting point.

3. A device for controlling the yaw performance of a two-axle, four-wheel vehicle which is equipped with a hydraulic brake system that includes a brake for each wheel, and with at least one sensor system or calculation models for establishing values which are members of the group consisting of wheel speeds, lateral acceleration, yaw velocity, steering angle, the steering angle velocity;

comprising at least two electronic yaw torque controllers, the first controller realizing an additional yaw torque MG_SESP to improve the track performance of the vehicle depending on a comparison between desired and actual yaw rates below an ESP intervention threshold and the second controller (10) putting this torque into practice to stabilize the driving state of the vehicle above the ESP intervention threshold by a corresponding brake application.

4. A comfort control system for a vehicle with an ESP controller for controlling an additional yaw torque, with a situation detection system in which different driving situations are distinguished and taken into consideration in the control, the control being active or inactive depending on control thresholds,

wherein an additional driving situation detection system is provided in which almost steady-state shapes of the course of the vehicle with a steering angle velocity of lower than, or equal to, 120°

/s are observed and analyzed, and in that depending on expected or actually determined comfort control deviations in the steady-state range indicative of a request by the driver and of the vehicle state, a modification of a reference value representing the desired course of the vehicle is activated when the control by the ESP controller is inactive.

5. The comfort control system as claimed in claim 4,

wherein additionally the desired course of the vehicle is determined in the ESP control and deviations from the desired course are evaluated, and it is determined during a desired course of driving if there is a tendency of a subsequent deviation from course due to a partial braking situation or load change situation.

6. A method of improving the control performance of a control system (ESP) wherein the rotational behavior of the vehicle is measured and evaluated as an input variable of the control system, wherein logical linking of the yaw rate with a desired course of the vehicle as intended by the driver is used to produce control variables for changing the vehicle course, and the control variables are set inactive or active depending on control thresholds in order to change the vehicle course, the method comprising the following steps:

changing the control thresholds depending on driving situations,

observing and analyzing deviations from the desired vehicle course with an almost steady-state shape of the course of the vehicle at a steering angle velocity of lower than, or equal to, 120°

/s,

and modifying a reference value representing the desired course of the vehicle in the event of expected or actually determined deviations in the steady-state range, when the control thresholds are below the control thresholds set higher steering angle velocities.

7. The method as claimed in claim 6,

Comprising the step of calculating a model-based vehicle reference speed from sensor signals of a driving stability control system.

8. Method as claimed in claim 7,

wherein the model-based vehicle reference speed is determined from at least one member of the group of quantities consisting of yaw velocity, steering wheel angle, lateral acceleration, steering wheel angle velocity, yaw acceleration, a quantity representative of any of the foregoing quantities, respectively.