JP2010012945A - Stop determination device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stop determination device capable of determining whether one's own vehicle is in a stopping state or not with a high degree of accuracy. <P>SOLUTION: The stop determination device is provided with a calculation part 11 calculating a stop-required time that the own vehicle C requires to stop based on the braking force and driving force of the own vehicle C when the own vehicle C is in a deceleration state, an elapse determination part 13 determining whether the stop-required time calculated by the calculation part 11 elapses or not, a wheel speed determination part 14 determining whether the number of wheels of the own vehicle C whose wheel speed is detected to be zero by the wheel speed sensor 5 becomes at least a predetermined number or not, and a stop determination part 15 determining the own vehicle C is in a stopping state when the elapse determination part 13 determines the elapse of the stop-required time, and the wheel speed determination part 14 determines that the number of wheels whose wheel speed is zero becomes the predetermined number or more. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a stop determination device that determines whether or not a host vehicle is stopped.

  Control of the maintenance function of the stop state provided in a vehicle such as an automobile is started immediately after the stop state. For this reason, it is necessary to accurately determine whether or not the vehicle has stopped in a short time of about 1 second immediately after the stop control is completed. This stop determination is usually performed by determining whether or not the vehicle speed obtained using the wheel speed is zero.

In obtaining vehicle speed using the wheel speeds of four wheels, for example, Patent Document 1 describes a technique for obtaining vehicle speed by eliminating noise to a wheel speed sensor at an extremely low vehicle speed of about 15 km / h. ing. In Patent Document 1, in order to detect the wheel speed, the number of falling edges and the required time of the wheel speed rectangular wave signal in a predetermined control cycle are detected, and the number of pulses of the rectangular wave therebetween is divided by the required time. Then, further calculation is performed by multiplying the conversion coefficient into speed, and the calculation result is used as the wheel speed.
JP 2000-19188 A

  The wheel speed sensor is affected by noise due to the influence of a magnetic field such as a road heater, vibrations due to brakes, and minute behaviors of many vehicle parts such as tire torsion. In particular, since the wheel speed sensor is easily affected by these noises at extremely low vehicle speeds, the technology described in Patent Document 1 has a vehicle speed with a high accuracy that can sufficiently ensure the accuracy of the stop determination described above. May not be calculated.

  Then, an object of this invention is to provide the stop determination apparatus which can determine accurately whether the own vehicle was in the stop state.

  That is, the stop determination device according to the present invention is a stop determination device that determines whether or not the host vehicle is in a stopped state, and when the host vehicle is in a deceleration state, the braking force and the driving force of the host vehicle. Based on the calculation means for calculating the required stop time required until the host vehicle stops, the progress determination means for determining whether the required stop time calculated by the calculation means has elapsed, and the wheel speed sensor It is determined by the wheel speed determination means that determines whether or not the number of wheels of the host vehicle detected that the wheel speed is zero has reached a predetermined number or more, and the time required for stopping has elapsed by the progress determination means, and And a stop determination unit that determines that the host vehicle has stopped when it is determined by the wheel speed determination unit that the number of wheels having zero wheel speed has reached a predetermined number or more.

  In the present invention, first, when the host vehicle is decelerated, the calculating means calculates the required stop time based on the braking force and driving force of the host vehicle, and whether or not the required stop time has elapsed. The determination means determines. Further, the wheel speed determining means determines whether or not the number of wheels detected as having a wheel speed of zero has reached a predetermined number or more. Here, when it is determined by the progress determining means that the required stop time has elapsed and the wheel speed determining means determines that the number of wheels whose wheel speed is zero has reached a predetermined number or more, the host vehicle stops. The stop determination means determines that the state has been reached.

  With this configuration, the condition that the host vehicle is in a decelerating state, the condition that it is determined that the required stop time has elapsed based on the braking force and driving force of the host vehicle, and the wheel speed is detected to be zero. When the condition that it is determined that the number of wheels has reached a predetermined number or more is satisfied, it is determined that the host vehicle has stopped. Here, instead of determining whether or not the vehicle has stopped using only the wheel speed sensor that is susceptible to noise, if all of the above conditions are satisfied, the host vehicle has been stopped. Therefore, it is possible to accurately determine whether or not the host vehicle has stopped.

  Further, it is preferable that the calculating means calculates the required stop time when the braking force is larger than the driving force. Thus, by calculating the required stop time when the braking force is greater than the driving force, it is possible to calculate the required stop time required until the host vehicle is decelerated until it stops.

  Further, it is preferable that the calculating means recalculates the required stop time when at least one of the braking force and the driving force changes. As described above, when at least one of the braking force and the driving force is changed, the required stop time is recalculated. Therefore, even if at least one of the braking force and the driving force is changed, the host vehicle is stopped. It can be determined with higher accuracy.

  ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide the stop determination apparatus which can determine accurately whether the own vehicle became the stop state.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings. In order to facilitate understanding of the description, the same components in the drawings are denoted by the same reference numerals as much as possible, and redundant description will be omitted.

  First, the structure of the stop determination device according to the embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic configuration diagram of a stoppage determination device 10 according to the present embodiment.

  The stop determination device 10 is a device that is attached to the host vehicle C (for example, a passenger car) and determines whether the host vehicle C is in a stopped state based on measurement values obtained by various sensors provided in the host vehicle C. is there. More specifically, the stop determination device 10 determines that the braking force of the host vehicle C (hereinafter referred to as deceleration force as a kind of braking force) is in a deceleration state greater than the driving force, and the deceleration force and driving force. When the condition that it is determined that the required stop time has passed and the condition that the number of wheels (ie, tires) detected that the wheel speed is zero is determined to be equal to or greater than the predetermined number is satisfied In addition, it is determined that the host vehicle C has stopped.

  The stop determination device 10 includes an ECU 1 (abbreviation of Electronic Control Unit, that is, an electronic control device) and various sensors 2 to 6 connected to the ECU 1. The various sensors 2 to 6 are the rotation speed sensor 2, the brake pressure sensor 3, the rudder angle sensor 4, the wheel speed sensor 5, and the G sensor 6. The brake pressure sensor 3 is connected to the brake 31.

  Here, the ECU 1 includes a calculation unit 11 (calculation unit), a timer 12 (time measurement unit), a progress determination unit 13 (progress determination unit), a wheel speed determination unit 14 (wheel speed determination unit), and a stop determination unit 15 (stop). Determination means). Functions of the calculation unit 11, the timer 12, the progress determination unit 13, the wheel speed determination unit 14, and the stop determination unit 15 are realized by the ECU 1. The ECU 1 is a unit whose main component is a microcomputer including a CPU, a ROM, a RAM, and the like.

  When the deceleration force of the host vehicle C enters a deceleration state larger than the driving force, the calculating unit 11 is based on the deceleration force and the driving force, the wheel speed detected by the wheel speed sensor 5, and the wheel speed. Based on the calculated vehicle speed, the stop required time Tstop is calculated and stored in the ECU 1. The stop required time Tstop is a time required from the start of time measurement by the timer 12 until the own vehicle C stops. The driving force of the host vehicle C is calculated by the rotation speed sensor 2 that measures the rotation speed of the motor of the host vehicle C. The deceleration force of the host vehicle C is calculated by the brake pressure sensor 3 that detects the pressure when the brake 31 is depressed (that is, the brake pressure). Further, the deceleration force of the host vehicle C is calculated by a steering angle value that is a value indicating the steering angle of the host vehicle C, that is, a steering angle sensor 4 that detects the direction of a wheel (for example, a front wheel).

  Note that the calculation unit 11 recalculates the required stop time Tstop and stores it in the ECU 1 when at least one of the deceleration force and the driving force of the host vehicle C changes. Further, the calculation unit 11 corrects the required stop time Tstop based on the steering angle value detected by the steering angle sensor 4 and causes the ECU 1 to store it. Moreover, the calculation part 11 may correct | amend the stop required time Tstop based on the acceleration added to the own vehicle C (for example, the gravity center of the own vehicle C). The acceleration applied to the host vehicle C is detected by the G sensor 6.

  The timer 12 is a part that counts (i.e., counts) elapsed time. In addition to this, the timer 12 can reset the counted measurement time.

  The progress determination unit 13 determines whether or not the required stop time Tstop calculated by the calculation unit 11 has elapsed after the timer 12 starts counting elapsed time (that is, timekeeping), and stores it in the ECU 1. It is.

  The wheel speed determination unit 14 is a part that determines whether or not the number of wheels detected as having a wheel speed of zero has reached a predetermined number or more and stores it in the ECU 1. This predetermined number is 3 (wheels) when the host vehicle C is a four-wheeled vehicle, and is one more than the number of drive wheels when the host vehicle C is other than a four-wheeled vehicle. The wheel speed of the host vehicle C, that is, the rotational speed of the wheel (for example, the front wheel) is preferably detected by a wheel speed sensor 5 having a dead band range. The range of the dead zone is a range in which the response detection of the wheel speed is not performed on the signal input to the wheel speed sensor 5. When noise exists within the dead zone, the noise is not included in the output value of the wheel speed sensor 5. The range of the dead zone is unique to the wheel and is set according to characteristics such as the wheel diameter.

  When the stop determination unit 15 determines that the required stop time Tstop has elapsed by the progress determination unit 13 and the wheel speed determination unit 14 determines that the number of wheels whose wheel speed is zero has reached a predetermined number or more. In addition, the vehicle C is a part that determines that the vehicle C has stopped and stores the determination result in the ECU 1.

  Next, a series of flows of a first example of processing executed by the stop determination device 10 will be described with reference to FIG. FIG. 2 is a flowchart for explaining a series of flows of a first example of processing executed by the stop determination device 10. The process shown in the flowchart of FIG. 2 is mainly performed by the ECU 1 and the various sensors 2 to 6, and is repeatedly executed at a predetermined timing from when the stop determination device 10 is turned on until it is turned off. The

  First, when the power of the stop determination device 10 is turned on, the timer 12 resets the measured time if it is already stored (step S01). And it transfers to below-mentioned step S02.

  In step S02, the rotational speed sensor 2 calculates the driving force of the host vehicle C, while the brake pressure sensor 3 and the rudder angle sensor 4 calculate the deceleration force, and the ECU 1 stores values relating to the driving force and the deceleration force. . And it transfers to below-mentioned step S11.

  In step S11, the calculation unit 11 determines whether or not the deceleration force calculated in step S02 is greater than the driving force, and causes the ECU 1 to store the determination result. When it is determined that the deceleration force is equal to or less than the driving force, the process returns to step S01 described above. On the other hand, when it is determined that the deceleration force is greater than the driving force, the process proceeds to step S12 described later.

  In step S12, the calculation unit 11 needs to stop based on the deceleration force and driving force calculated in step S02, the wheel speed detected by the wheel speed sensor 5, and the vehicle speed calculated based on the wheel speed. The time Tstop is calculated and stored in the ECU 1. And it transfers to below-mentioned step S21.

  In step S21, the calculation unit 11 corrects the required stop time Tstop based on the steering angle value, which is a value indicating the steering angle of the host vehicle C, and stores it in the ECU 1. And it transfers to below-mentioned step S22.

  In step S22, the timer 12 starts counting elapsed time. And it transfers to step S23 mentioned later.

  In step S23, it is determined whether or not the brake pressure sensor 3 has detected a change in brake pressure, and the determination result is stored in the ECU 1, while whether or not the steering angle sensor 4 has detected a change in steering angle. Determination is made and the determination result is stored in the ECU 1. If at least one of the brake pressure and the steering angle changes, the process returns to step S02 described above. On the other hand, if neither the brake pressure nor the steering angle has changed, the process proceeds to step S24 described later.

  In step S24, the progress determination unit 13 determines whether or not the required stop time Tstop has elapsed since the elapsed time started in step S22, and the determination result is stored in the ECU 1. When it is determined that the required stop time Tstop has not yet elapsed, the process returns to step S23 described above. On the other hand, when it is determined that the required stop time Tstop has already elapsed, the process proceeds to step S31 described later.

  In step S31, in the wheel speed sensor 5, the range of the dead zone is set by the ECU 1 and stored. The range of the dead zone is a range in which the response detection of the wheel speed is not performed on the signal input to the wheel speed sensor 5. The range of the dead zone is unique to the wheel and is set according to characteristics such as the wheel diameter. And it transfers to below-mentioned step S41.

  In step S41, the wheel speed determination unit 14 determines whether or not the number of wheels detected by the wheel speed sensor 5 in which the range of the dead zone is set as zero is equal to or greater than a predetermined number, The determination result is stored in the ECU 1. If it is determined that the number of wheels detected as having zero wheel speed is not equal to or greater than the predetermined number, step S41 is performed again. On the other hand, when it is determined that the number of wheels detected as having a wheel speed of zero has reached a predetermined number or more, the process proceeds to step S51 described below.

  In step S51, the stop determination unit 15 determines that the host vehicle C is in a stop state, and stores the determination result in the ECU 1. As a result, the process executed by the stop determination device 10 ends, and the process proceeds to step S01 again at a predetermined timing.

  Next, a series of flows of a second example of processing executed by the stop determination device 10 will be described with reference to FIG. FIG. 3 is a flowchart for explaining a series of flows of a second example of processing executed by the stop determination device 10. The process shown in the flowchart of FIG. 3 is mainly performed by the ECU 1 and the various sensors 2 to 6 as in the first example, and from when the stop determination device 10 is turned on until it is turned off. It is repeatedly executed at a predetermined timing.

  First, when the power of the stop determination device 10 is turned on, the timer 12 resets the measured time if it is already stored (step S01). And it transfers to below-mentioned step T02.

  In step T02, the rotation speed sensor 2 calculates the driving force of the host vehicle C, and stores a value related to the driving force in the ECU 1. And it transfers to below-mentioned step T03.

  In step T03, the brake pressure sensor 3 that detects the brake pressure and the rudder angle sensor 4 that detects the rudder angle communicate with each other via the ECU 1 to calculate a deceleration force. Remember. And it transfers to below-mentioned step T11.

  In step T11, the calculation unit 11 determines whether or not the deceleration force calculated in step T02 is greater than the driving force, and causes the ECU 1 to store the determination result. When it is determined that the deceleration force is equal to or less than the driving force, the process returns to step T01 described above. On the other hand, when it is determined that the deceleration force is greater than the driving force, the process proceeds to Step T12 described later.

  In step T12, the calculation unit 11 calculates the driving force calculated in step T02, the deceleration force calculated in step T03, the wheel speed detected by the wheel speed sensor 5, and the vehicle speed calculated based on the wheel speed. Based on the above, the required stop time Tstop is calculated and stored in the ECU 1. And it transfers to below-mentioned step T13.

  In step T13, the brake pressure of the host vehicle C detected by the brake pressure sensor 3 is stored in the ECU 1, while the steering angle of the host vehicle C detected by the steering angle sensor 4 is stored in the ECU 1. And it transfers to below-mentioned step T21.

  In step T21, the calculation unit 11 corrects the required stop time Tstop based on the steering angle value, which is a value indicating the steering angle of the host vehicle C, and stores it in the ECU 1. And it transfers to below-mentioned step T22.

  In step T22, the timer 12 starts counting elapsed time. And it transfers to step T23 mentioned later.

  In step T23, it is determined whether or not the brake pressure sensor 3 has detected a change in brake pressure, and the determination result is stored in the ECU 1, while whether or not the steering angle sensor 4 has detected a change in steering angle. Determination is made and the determination result is stored in the ECU 1. The ECU 1 determines whether or not the brake pressure and the steering angle have changed, based on the values stored in step T13. When at least one of the brake pressure and the steering angle changes, the process returns to step T02 described above. On the other hand, if neither the brake pressure nor the steering angle has changed, the process proceeds to step T24 described later.

  In step T24, the progress determination unit 13 determines whether or not the required stop time Tstop has elapsed since the elapsed time was started in step T22, and the determination result is stored in the ECU 1. When it is determined that the required stop time Tstop has not yet elapsed, the process returns to step T23 described above. On the other hand, when it is determined that the required stop time Tstop has already elapsed, the process proceeds to step T31 described later.

  In step T31, in the wheel speed sensor 5, the dead zone range is set by the ECU 1 and stored. And it transfers to below-mentioned step T32.

  In step T32, the wheel speed sensor 5 detects the wheel speed for all the wheels, calculates and sets the maximum wheel speed of all the wheel speeds as the current vehicle speed of the host vehicle C, and stores it in the ECU 1. . And it transfers to below-mentioned step T41.

  In step T41, the wheel speed determination unit 14 determines whether or not the number of wheels detected by the wheel speed sensor 5 in which the range of the dead zone is set as zero is equal to or greater than a predetermined number, The determination result is stored in the ECU 1. If it is determined that the number of wheels detected as having zero wheel speed is not equal to or greater than the predetermined number, step T41 is performed again. On the other hand, when it is determined that the number of wheels detected as having a wheel speed of zero has reached a predetermined number or more, the process proceeds to step T51 described below.

  In step T51, the stop determination unit 15 determines that the host vehicle C is in a stop state, and stores the determination result in the ECU 1. As a result, the process executed by the stop determination device 10 ends, and the process proceeds to step T01 again at a predetermined timing.

  Continuously, the effect of this embodiment is demonstrated. According to the present embodiment, first, when the host vehicle C is in a deceleration state, the calculation unit 11 calculates the required stop time Tstop based on the braking force and the driving force of the host vehicle C, and this required stop time Tstop. The progress determination unit 13 determines whether or not elapses. Moreover, the wheel speed determination part 14 determines whether the number of the wheels detected that the wheel speed was zero became more than predetermined number. Here, when it is determined by the progress determination unit 13 that the required stop time Tstop has elapsed, and the wheel speed determination unit 14 determines that the number of wheels whose wheel speed is zero has reached a predetermined number or more, The stop determination unit 15 determines that the vehicle C has stopped.

  With this configuration, the condition that the host vehicle C is in a decelerating state, the condition that it is determined that the required stop time Tstop based on the braking force and the driving force of the host vehicle C has elapsed, and the wheel speed is zero. When the condition that it is determined that the number of detected wheels is equal to or greater than the predetermined number is satisfied, it is determined that the host vehicle C has stopped. Here, instead of determining whether or not the vehicle is stopped using only the wheel speed sensor that is easily affected by noise, the host vehicle C enters the stopped state when all the above three conditions are satisfied. Therefore, it can be accurately determined whether or not the vehicle is stopped.

  Further, by calculating the required stop time Tstop when the deceleration force is larger than the driving force, it is possible to calculate the required stop time Tstop required until the host vehicle C stops after the vehicle C is decelerated.

  In addition, when at least one of the deceleration force and the driving force is changed, the required stop time Tstop is recalculated. Therefore, even if at least one of the deceleration force and the driving force is changed, the host vehicle C is stopped. It can be determined with higher accuracy.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments. For example, in the above-described embodiment, the ECU 1 includes the calculation unit 11, the timer 12, the progress determination unit 13, the wheel speed determination unit 14, and the stop determination unit 15, but these are separately separated and independent. It is good.

It is a composition schematic diagram of the stop judging device concerning this embodiment. It is a flowchart for demonstrating a series of flows of the 1st example of the process performed with a stop determination apparatus. It is a flowchart for demonstrating a series of flows of the 2nd example of the process performed with a stop determination apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... ECU, 2 ... Rotation speed sensor, 3 ... Brake pressure sensor, 4 ... Rudder angle sensor, 5 ... Wheel speed sensor, 6 ... G sensor, 10 ... Stop determination apparatus, 11 ... Calculation part, 12 ... Timer, 13 ... Progress determination unit, 14 ... wheel speed determination unit, 15 ... stop determination unit, 31 ... brake, C ... own vehicle.

Claims (3)

A stop determination device for determining whether or not the host vehicle is stopped,
A calculating means for calculating a required stop time required for the host vehicle to stop based on a braking force and a driving force of the host vehicle when the host vehicle is in a deceleration state;
Progress determining means for determining whether or not the required stop time calculated by the calculating means has elapsed;
Wheel speed determination means for determining whether or not the number of wheels of the host vehicle detected by the wheel speed sensor as being zero is greater than or equal to a predetermined number;
When it is determined by the progress determining means that the required stop time has elapsed, and the wheel speed determining means determines that the number of wheels whose wheel speed is zero has reached the predetermined number or more, the host vehicle Is a stop determination means for determining that the vehicle is stopped;
A stop determination device comprising:   The stop determination device according to claim 1, wherein the calculation means calculates the required stop time when the braking force is greater than the driving force. The stop determination device according to claim 1 or 2, wherein the calculation means recalculates the required stop time when at least one of the braking force and the driving force changes.

Images