Vehicle drive control apparatus

• US 8,498,802 B2
• Filed: 12/14/2010
• Issued: 07/30/2013
• Est. Priority Date: 05/08/2009
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Yamamoto, Shinsuke
• Primary Examiner(s): Tran, Khoi
• Assistant Examiner(s): LIN, ABBY YEE
• Application Number:
  US12/967,258
• Publication Number:
  US 20110082624A1
• Time in Patent Office: 959 Days
• Field of Search: 701/41, 701 70- 76, 701/78, 701/79, 701/81, 701/82, 701/90, 701/91, 701/93, 701/96, 701/110, 701/112, 701/113, 701/117, 701/124, 701/86, 475/2, 475 18- 30, 477/10, 477/19, 477/99, 477175-179, 180/6.2, 180/6.54, 180116-119, 180/234, 180408-410, 180443-446, 188/350, 280 55- 5513
• US Class Current: 701/112
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 2510/202 Steering torque
• CPC Class Codes: B60W 2520/125 Lateral acceleration
• CPC Class Codes: B60W 2520/14 Yaw
• CPC Class Codes: B60W 30/18018 Start-stop drive, e.g. in a traffic jam
• CPC Class Codes: F02D 29/02 peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• CPC Class Codes: F02N 11/0825 related to prevention of engine restart failure, e.g. disabling automatic stop at low battery state
• CPC Class Codes: F02N 11/0833 Vehicle conditions F02N11/0822, F02N11/0825 take precedence
• CPC Class Codes: F02N 11/084 State of vehicle accessories, e.g. air condition or power steering
• CPC Class Codes: F02N 11/10 Safety devices F02N11/08 takes precedence
• CPC Class Codes: F02N 2200/0805 Detection of vehicle emergency state, e.g. from ABS, ESP, external sensors
• CPC Class Codes: F02N 2200/0808 Steering state, e.g. state of power assisted steering
• CPC Class Codes: F02N 2200/104 Driver's intention to turn, e.g. by evaluating direction indicators
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

In a vehicle drive control apparatus, a behavior determination unit determines whether a vehicle behavior is in a stable state or an unstable state based on a vehicle turning behavior. An engine stop control unit avoids stopping the engine as automatic stop conditions are not satisfied when the vehicle behavior is determined to be in an unstable state during operation of the engine. When the vehicle behavior is in a stable state and other automatic stop conditions are satisfied during operation of the engine, the engine stop control unit stops the engine. During stability control performed by a stability ECU, the engine stop control unit avoids stopping the engine as the automatic stop conditions are not satisfied.

Claims

1. A vehicle drive control apparatus comprising:

an electronic control unit including

an engine stop control unit which stops an engine when an automatic stop condition for automatically stopping the engine is satisfied during operation of the engine, and

a behavior determination unit which determines whether a behavior of a vehicle is in a stable state or an unstable state based on a difference between a current yaw rate measurement and a previous yaw rate measurement, wherein

the engine stop control unit avoids stopping the engine when the behavior of the vehicle is determined to be in the unstable state, the automatic stop condition not being satisfied when the behavior of the vehicle is determined to be in an unstable state during operation of the engine,

the behavior determination unit determines whether the behavior of the vehicle is in a stable state or an unstable state based on a turning behavior of the vehicle,

the vehicle includes a lateral acceleration sensor and a yaw rate sensor to determine the turning behavior of the vehicle, and

stability of the vehicle is determined when a yaw rate variation amount compared to a previous detection value detected by the yaw rate sensor is smaller than a predetermined threshold.

2. The vehicle control apparatus according to claim 1, wherein stability of the vehicle is determined when a lateral acceleration variation amount compared to a previous detection value detected by the lateral acceleration sensor is smaller than a predetermined threshold.

3. The vehicle control apparatus according to claim 2, wherein the vehicle is determined to be in an unstable state when a current lateral acceleration is above a predetermined lateral acceleration threshold, the current yaw rate measurement is above a predetermined yaw threshold, or a difference between the current lateral acceleration and a previous lateral acceleration is above a second predetermined threshold.

4. A vehicle drive control apparatus comprising:

an electronic control unit including

an engine stop control unit which stops an engine when an automatic stop condition for automatically stopping the engine is satisfied during operation of the engine, and

a behavior determination unit which determines whether a behavior of a vehicle is in a stable state or an unstable state based on a difference between a current yaw rate measurement and a previous yaw rate measurement, wherein

the engine stop control unit avoids stopping the engine when the behavior of the vehicle is determined to be in the unstable state, the automatic stop condition not being satisfied when the behavior of the vehicle is determined to be in an unstable state during operation of the engine,

the behavior determination unit determines whether the behavior of the vehicle is in a stable state or an unstable state based on a turning behavior of the vehicle,

the vehicle includes a lateral acceleration sensor and a yaw rate sensor to determine the turning behavior of the vehicle, and

wherein stability of the vehicle is determined when a yaw rate variation amount compared to a previous detection value detected by the yaw rate sensor is smaller than a predetermined threshold, the vehicle is determined to be in an unstable state when a current lateral acceleration is above a predetermined lateral acceleration threshold, the current yaw rate measurement is above a predetermined yaw threshold, and a difference between the current lateral acceleration and a previous lateral acceleration is above a second predetermined threshold.