VEHICLE

• US 20110118948A1
• Filed: 05/27/2009
• Published: 05/19/2011
• Est. Priority Date: 05/27/2009
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Naito, Masayuki, Ohbayashi, Motonari, Nishimura, Ayako
• Granted Patent: US 8,700,281 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60T 2250/04 Vehicle reference speed; Vehicle body speed
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence

Abstract

Disclosed is a vehicle capable of improving the accuracy of wheel stopping determination. A stopping determination time which is calculated by multiplying the pulse width of a wheel speed pulse immediately before a non-output time, for which no wheel speed pulse is output from a wheel speed sensor 3, by 2^1/2+1, or a corrected time which is corrected on the basis of the stopping determination time is set as a threshold value for determining stopping of wheels. The wheel speed pulse which is output immediately before the non-output time is output when the wheels are substantially in the stopping state. Thus, the time corresponding to the pulse width of the wheel speed pulse is multiplied by 2^1/2+1 which is a constant taking into consideration the deceleration and traveling distance of the vehicle, thereby obtaining an optimum threshold value for determining the stopping of the wheels. For this reason, the stopping of the wheels is determined on the basis of the stopping determination time or the corrected time, such that the stopping of the wheels can be determined rapidly and accurately. Therefore, it becomes possible to improve the accuracy of wheel stopping determination.

Claims

1. A vehicle comprising:

a wheel speed sensor which outputs a wheel speed pulse in accordance with the rotation of wheels; and

a wheel stopping determination unit which determines whether the rotation of the wheels is stopped or not on the basis of the wheel speed pulse output from the wheel speed sensor,

wherein, when a non-output time for which no wheel speed pulse is output from the wheel speed sensor is equal to or longer than a stopping determination time which is calculated by multiplying a time corresponding to the pulse width of a wheel speed pulse output from the wheel speed sensor before the non-output time by 2^1/2+1 or a corrected time which is corrected on the basis of the stopping determination time, the wheel stopping determination unit determines that the rotation of the wheels is stopped.

3. The vehicle according to claim 1 or 2, further comprising:

a vehicle stopping determination unit which, when the wheel stopping determination unit determines that at least one wheel is stopped, determines whether the vehicle is stopped or not on the basis of whether or not the behavior of the vehicle is stable.

4. The vehicle according to any one of claims 1 to 3, wherein the corrected time is a time which is obtained by adding a change rate of the driving force or braking force of the vehicle to the stopping determination time.

5. The vehicle according to any one of claims 1 to 3, wherein the corrected time is a time which is obtained by adding a change rate of force applied to tires calculated on the basis of the driving force and braking force of the vehicle to the stopping determination time.

6. The vehicle according to any one of claims 1 to 5, wherein the time corresponding to the pulse width is a time from the rising edge to the falling edge in the wheel speed pulse or a time from the falling edge to the rising edge in the wheel speed pulse.

2. A vehicle comprising:

a wheel speed sensor which outputs a wheel speed pulse in accordance with the rotation of wheels;

a wheel stopping determination unit which determines whether the rotation of the wheels is stopped or not on the basis of the wheel speed pulse output from the wheel speed sensor; and

a vehicle control unit which performs vehicle control after the wheel stopping determination unit has determined that the rotation of the wheels is stopped,

wherein, when a non-output time for which no wheel speed pulse is output from the wheel speed sensor is equal to or longer than a stopping determination time which is calculated by multiplying a time corresponding to the pulse width of a wheel speed pulse output from the wheel speed sensor before the non-output time by 2^1/2+1 or a corrected time which is corrected on the basis of the stopping determination time, the wheel stopping determination unit determines that the rotation of the wheels is stopped.