JP6245076B2 - Output correction device for vehicle acceleration sensor - Google Patents

Description

  The present invention relates to an output correction technique for an acceleration sensor mounted on a vehicle.

  Conventionally, as a technique for correcting an output value of an acceleration sensor mounted on a vehicle, there is a technique described in Patent Document 1. In this technique, the output value of the acceleration sensor when the vehicle is traveling straight, traveling at a constant speed, and traveling on a flat road is determined as a drift value (offset value). Then, the output value of the acceleration sensor is corrected by gradually or gradually changing the correction value so that the determined offset value is eliminated. In this way, by changing the correction value gently or gradually, a sudden change in the corrected sensor output value is suppressed, so that no inconvenience occurs in the control using the sensor output value.

JP 2006-250947 A

However, in the environment where the control using the output value of the acceleration sensor is constantly operating, the time until the offset correction is completed when the correction value is changed slowly or gradually at a constant rate of change. Becomes longer. As a result, there is a possibility that a problem with control due to a delay in correction occurs.
The present invention has been made paying attention to the above points, and the true value of the sensor output value while suppressing the occurrence of the driver's uncomfortable feeling to the change in the acceleration / deceleration of the vehicle due to the correction of the output value of the acceleration sensor. An object of the present invention is to provide an output correction device for a vehicle acceleration sensor capable of improving the convergence speed.

  In order to solve the above problems, according to one embodiment of the present invention, an offset estimated value that is an estimated value of an offset value of an acceleration sensor mounted on a vehicle is calculated, and the sensor output of the acceleration sensor is canceled so that the offset estimated value is canceled out. Correction is performed by adding a correction value to the value. At that time, based on the operation state of the braking / driving force indicating operator for instructing the braking / driving force of the vehicle, the magnitude of the driver's sensitivity to the acceleration or deceleration of the vehicle caused by the traveling control using the corrected sensor output value When the acceleration or deceleration direction of the vehicle caused by the operation of the braking / driving force indicating operator is the same as the acceleration or deceleration direction of the vehicle caused by the travel control using the corrected sensor output value The driver sensitivity sensitivity value is set to be smaller as the operation state of the braking / driving force instruction operator is an operation state in which the rate of change of the acceleration / deceleration of the vehicle is increased. Then, the correction value is limited so that the change in the sensor output value decreases as the driver sensitivity sensitivity value increases.

According to one aspect of the present invention, the magnitude of the correction value to be added to the sensor output value is limited so that the change in the sensor output value decreases as the driver sensitivity sensitivity value increases.
Here, the sensitivity of the driver to the acceleration / deceleration generated in the vehicle changes in accordance with the operation state of the braking / driving force instruction operator (for example, the operation speed of the accelerator pedal). When the driver's sensitivity to acceleration / deceleration is large, it becomes sensitive to changes in acceleration / deceleration, so vehicle acceleration / deceleration caused by travel control using the sensor output value after correction (hereinafter referred to as “vehicle acceleration / deceleration due to correction”) The sensitivity of the driver to changes in In addition, when the driver's sensitivity to acceleration / deceleration is small, the driver's sensitivity to changes in the vehicle's acceleration / deceleration due to correction is reduced because the driver's sensitivity is insensitive.

That is, according to one aspect of the present invention, the limit value of the correction value is increased so that the change in the sensor output value becomes smaller as the driver sensitivity to the change in the vehicle acceleration / deceleration caused by the correction increases. It is possible to reduce the limit value of the correction value so that the change in the sensor output value increases as the value decreases.
As a result, the driver changes the acceleration / deceleration of the vehicle (hereinafter referred to as “vehicle acceleration / deceleration caused by the operation”) caused by the operation of his / her braking / driving force indicator operator, and the vehicle's acceleration / deceleration caused by the correction. It is possible to make it difficult to distinguish from a change in speed, and it is possible to change the correction amount according to the magnitude of the driver sensitivity sensitivity value. For this reason, it is possible to improve the convergence speed of the sensor output value to the true value while suppressing the occurrence of the driver's uncomfortable feeling with respect to the vehicle acceleration / deceleration change caused by the correction.

It is a block diagram which shows schematic structure of the output correction apparatus of the acceleration sensor for vehicles of 1st Embodiment. It is a block diagram which shows the example of 1 structure of the sensor output correction apparatus of 1st Embodiment. It is a block diagram which shows the structure of the controller 10 of 1st Embodiment. It is a time chart which shows an example of the time change of correction permission coefficient Cp of 1st Embodiment, rate limiter constant RL, and limit correction value CL. It is a flowchart which shows an example of the process sequence of a sensor output correction process. It is a figure which shows an example of the driver sensitivity sensitive term map at the time of acceleration side correction, and the driver sensitivity sensitive term map at the time of deceleration side correction. (A) is a figure which shows an example of a steering angle sensitive term map, (b) is a figure which shows an example of a vehicle speed sensitive term map, (c) is a figure which shows an example of a vehicle acceleration sensitive term map. (D) is a figure which shows an example of an offset estimated value sensitive term map. Time variation of the accelerator operation amount AC, the correction permission coefficient Cp, the estimated offset value Gos, the limit correction value CL, the sensor output value Ga, the corrected sensor output value Gc, and the true value Gt of the sensor output value. It is a time chart which shows an example. It is a figure explaining the effect of a 1st embodiment. It is a block diagram which shows the structure of the controller 10 of 2nd Embodiment. It is a figure which shows an example of the driver sensitivity sensitive term map of 2nd Embodiment. It is a block diagram which shows the structure of the controller 10 of 3rd Embodiment. It is a figure which shows an example of the driver sensitivity sensitive term table of 3rd Embodiment.

(First embodiment)
(Constitution)
As shown in FIGS. 1 and 2, an output correction device 1 for a vehicle acceleration sensor according to a first embodiment includes an acceleration sensor 2, an accelerator sensor 3, a brake sensor 4, a wheel speed sensor 5, a steering mounted on the vehicle. An angle sensor 6, a motor current sensor 7, a shift sensor 8, and a controller 10 are included.

Hereinafter, the output correction device 1 of the vehicle acceleration sensor is referred to as a “sensor output correction device 1”.
The acceleration sensor 2 detects acceleration acting on the vehicle and supplies an acceleration signal (voltage signal) indicating the detected acceleration to the controller 10. The controller 10 determines the acceleration detected by the acceleration sensor 2 from the input acceleration signal.
Here, the acceleration sensor 2 has an offset value in its sensor output. That is, when the acceleration acting on the vehicle body is 0 [G], the output voltage does not become 0 and an offset voltage is output. Since the offset voltage varies depending on the surrounding environment such as temperature, it is preferable to remove the offset voltage from the sensor output.

The acceleration sensor 2 is a sensor that detects at least the acceleration in the vehicle longitudinal direction among the acceleration in the vehicle longitudinal direction, the acceleration in the vehicle horizontal direction, and the acceleration in the vehicle vertical direction.
The accelerator sensor 3 detects an operation amount (hereinafter referred to as “accelerator operation amount AC”) by the driver's operation of the accelerator pedal 30, and inputs the detection result to the controller 10. The accelerator sensor 3 is a potentiometer, for example, and converts the operation position of the accelerator pedal 30 into a voltage signal and inputs the voltage signal to the controller 10. The controller 10 determines the operation position (stroke amount) of the accelerator pedal 30 from the input voltage signal.

The brake sensor 4 detects an operation amount (hereinafter referred to as a brake operation amount BR) by the driver's operation of the brake pedal 32 and outputs the detection result to the controller 10.
Here, the vehicle of the first embodiment includes an electronic control brake system (not shown). Moreover, as shown in FIG. 1, the brake actuator 12 corresponding to each wheel 13FL, 13FR, 13RL, and 13RR is provided.

The brake actuator 12 is interposed between the master cylinder and the wheel cylinder corresponding to each wheel. In the first embodiment, each wheel cylinder is built in a disc brake that generates a braking force by pressing a disc rotor with a brake pad.
The brake actuator 12 of the first embodiment uses a braking fluid pressure control circuit used for anti-skid control, traction control, stability control, and the like. Therefore, it is possible to control the increase / hold / reduction of the hydraulic pressure of each wheel cylinder based on the brake operation amount (stroke amount of the brake pedal 32) BR of the driver.

  The wheel speed sensor 5 detects wheel speeds Vh1, Vh2, Vh3, and Vh4 of the wheels 13FL, 13FR, 13RL, and 13RR, and inputs a wheel speed signal indicating the detection result to the controller 10. The wheel speed sensor 5 detects, for example, the magnetic lines of force of the sensor rotor by a detection circuit, converts a change in the magnetic field accompanying the rotation of the sensor rotor into a current signal, and inputs the current signal to the controller 10. The controller 10 determines the wheel speeds Vh1 to Vh4 from the input current signal.

The steering angle sensor 6 detects a steering angle θ that is a rotation angle of a steering wheel (not shown) provided in the vehicle. Then, a steering angle signal indicating the detected steering angle θ is input to the controller 10.
The motor current sensor 7 detects a motor current Im of a braking / driving motor 22 described later, and inputs a motor current signal indicating the detection result to the controller 10.

The shift sensor 8 detects the shift position of the shift lever 34 that changes the shift position (for example, “P”, “D”, “L”, “R”, etc.) of the transmission mounted on the vehicle. Then, a shift position signal SP indicating the detected shift position is input to the controller 10.
The controller 10 is composed of, for example, a microcomputer, and performs sensor output correction processing, which will be described later, based on detection signals from the sensors, and performs offset correction of the sensor output value of the acceleration sensor 2. Then, the corrected sensor output value is supplied to each component that uses the sensor output value of the acceleration sensor 2 such as the driving support device 20 for control.

Here, the offset correction is to correct the sensor output value of the acceleration sensor 2 so as to cancel an offset estimated value Gos described later.
The driving support device 20 is a device that performs driving support control of the vehicle using the sensor output value after offset correction supplied from the controller 10.
Here, the travel support control includes VDC (Vehicle Dynamics Control), gradient assist, ACC (Adaptive Cruise Control), CACC (Cooperative ACC), and the like.

The motor power supply inverter 21 controls the motor output (the number of revolutions and the motor torque) via the inverter. Specifically, the motor power supply inverter 21 controls the power supplied to the braking / driving motor 22 so that the braking / driving force according to the braking / driving force generation command output from the travel support device 20 or the like is generated.
The braking / driving motor 22 is driven by the drive wheels 13FL and 13FR so that the braking / driving force corresponding to the braking / driving force generation command output from the travel support device 20 or the like is generated by the power supplied from the motor power supply inverter 21. Controls the braking / driving force.

(Controller 10)
Next, based on FIG. 3, the structure of the controller 10 of 1st Embodiment is demonstrated.
As shown in FIG. 3, the controller 10 includes a drive torque estimating unit 100, an acceleration estimated value calculating unit 101, an offset estimated value calculating unit 102, an operation state detecting unit 103, a driver sensitivity sensitive term calculating unit 104, The correction reliability calculation unit 105, the correction permission coefficient calculation unit 106, the correction value restriction unit 107, and the output value correction unit 108 are configured.

  The drive torque estimation unit 100 is configured by a drive torque observer in the first embodiment. Based on the motor current Im from the motor current sensor 7 and the wheel speeds Vh1 and Vh2 of the drive wheels 13FL and 13FR from the wheel speed sensor 5, the drive torque estimation unit 100 uses the drive torque observer to drive torque applied to the vehicle. Is estimated. Then, an estimated torque Te value that is an estimated value of the driving torque is input to the estimated acceleration value calculation unit 101.

  In the first embodiment, since the driving source of the vehicle is the braking / driving motor 22, the driving torque is estimated using a driving torque observer. Therefore, for example, when the drive source is an internal combustion engine (engine), the torque acting on the shaft of the engine may be detected by, for example, a torque sensor, and the drive torque may be estimated from the detection result. For example, it is good also as a structure which measures the torque around an axle shaft with a wheel torque meter, and estimates a drive torque from the measurement result.

The acceleration estimated value calculation unit 101 is an estimated value of the acceleration Ga generated in the vehicle based on the torque estimated value Te input from the drive torque estimating unit 100 and the wheel speeds Vh1 to Vh4 input from the wheel speed sensor 5. A certain acceleration estimated value Ge is calculated.
Specifically, the acceleration estimated value calculation unit 101 first calculates the vehicle speed V of the vehicle from the wheel speeds Vh <b> 1 to Vh <b> 4 input from the wheel speed sensor 5. For example, the average value of the wheel speeds Vh3 to Vh4 of the rear wheels 13RL and 13RR that are driven wheels is calculated as the vehicle speed V.

Next, the acceleration estimated value calculation unit 101 calculates a running resistance R from the calculated vehicle speed V. Here, the running resistance R is an air resistance component and a resistance component proportional to the square value of the vehicle speed V. The acceleration estimated value calculation unit 101 of the first embodiment calculates the running resistance R by multiplying the square value (V ² ) of the input vehicle speed V by a fixed gain K. Then, the estimated acceleration value Ge is calculated from the estimated torque value Te, the running resistance R, and the vehicle weight M stored in advance in a memory (not shown) according to the following equation (1).
Ge = (Te−R) / M (1)

That is, as shown in the above equation (1), the acceleration estimated value calculation unit 101 calculates the acceleration estimated value Ge by dividing the subtraction result obtained by subtracting the running resistance R from the torque estimated value Te by the vehicle weight M. .
The acceleration estimated value calculation unit 101 inputs the calculated acceleration estimated value Ge to the offset estimated value calculation unit 102 and the correction reliability calculation unit 105, respectively. Further, the estimated acceleration value calculation unit 101 inputs the calculated vehicle speed V to the correction reliability calculation unit 105.

The offset estimated value calculation unit 102 is based on the sensor output value Ga input from the acceleration sensor 2 and the acceleration estimated value Ge input from the acceleration estimated value calculation unit 101 according to the following equation (2), and the offset estimated value Gos. Is calculated.
Gos = Ge-Ga (2)
That is, as shown in the above equation (2), the estimated offset value calculation unit 102 calculates the estimated offset value Gos by subtracting the sensor output value Ga from the estimated acceleration value Ge. The offset estimated value calculating unit 102 inputs the calculated offset estimated value Gos to the driver sensitivity sensitive term calculating unit 104, the correction reliability calculating unit 105, and the correction value limiting unit 107, respectively.

  In the first embodiment, the operation state detection unit 103 detects an accelerator operation speed As that is an operation speed of the accelerator pedal 30 based on the accelerator operation amount AC input from the accelerator sensor 3. Specifically, the operation state detection unit 103 calculates the accelerator operation speed As by differentiating the input accelerator operation amount AC. The operation state detection unit 103 inputs the calculated accelerator operation speed As to the driver sensitivity sensitive term calculation unit 104.

The driver sensitivity sensitive term calculation unit 104 calculates a correction permission coefficient Cp described later based on the offset estimated value Gos input from the offset estimated value calculation unit 102 and the accelerator operation speed As input from the operation state detection unit 103. The driver sensitivity sensitive term Ds used in the above is calculated.
Here, the corrected value of the sensor output value Ga that changes according to the operation state of the accelerator pedal 30 (accelerator operation speed As in the first embodiment) is used as the driver sensitivity sensitivity term Ds of the first embodiment. This is an index value of a driver sensitivity sensitivity value that is a value indicating the magnitude of the driver's sensitivity to a change in vehicle acceleration / deceleration caused by travel control.

Hereinafter, the acceleration / deceleration of the vehicle caused by the travel control using the corrected value of the sensor output value Ga may be referred to as “the acceleration / deceleration of the vehicle due to the correction of the sensor output value Ga”.
Further, in the first embodiment, the driver sensitivity sensitivity value is the acceleration or deceleration of the vehicle caused by the operation of the accelerator pedal 30 and the acceleration or deceleration of the vehicle caused by the travel control using the corrected value of the sensor output value Ga. When the deceleration direction is the same direction, the operation state of the accelerator pedal 30 becomes smaller as the operation state increases the rate of change of the acceleration / deceleration of the vehicle.

Hereinafter, the acceleration or deceleration of the vehicle caused by the operation of the accelerator pedal 30 may be referred to as “acceleration or deceleration of the vehicle due to the operation state of the accelerator pedal 30”. Further, the acceleration or deceleration of the vehicle caused by the travel control using the corrected value of the sensor output value Ga may be referred to as “acceleration or deceleration of the vehicle due to the correction of the sensor output value Ga”.
When the operating speed of the accelerator pedal 30 is high, the rate of change in the acceleration / deceleration of the vehicle due to this operating state increases, so the driver's sensitivity to changes in the acceleration / deceleration of the vehicle becomes relatively small. On the other hand, when the operation speed is low, the rate of change in the acceleration / deceleration of the vehicle due to this operation state is small, so the sensitivity of the driver to the change in the acceleration / deceleration of the vehicle is relatively high. That is, the change in the vehicle acceleration / deceleration caused by the correction of the sensor output value Ga (hereinafter sometimes simply referred to as “correction”) that occurs when the driver's sensitivity to the change in the vehicle acceleration / deceleration is small is felt by the driver. Hateful. Therefore, the driver's sensitivity to changes in the vehicle acceleration / deceleration caused by the correction is reduced. On the other hand, a change in the acceleration / deceleration of the vehicle due to the correction of the sensor output value Ga, which occurs when the sensitivity of the driver to the change in the acceleration / deceleration of the vehicle is large, is easily felt by the driver. Therefore, the driver's sensitivity to changes in the vehicle acceleration / deceleration caused by the correction increases.

Based on this, in the first embodiment, for example, from the sensitivity data for the change in the acceleration / deceleration of the vehicle due to the above-described correction of an unspecified number of drivers with respect to the accelerator operation speed, obtained from the experiment, the driver sensitivity sensitivity term A map of Ds is created in advance. The map created in this way is stored in advance in a memory (not shown) provided in the sensor output correction device 1.
Here, the change in the acceleration / deceleration of the vehicle due to the correction means that when the sensor output value Ga is corrected so as to cancel the offset estimated value Gos, control using the corrected sensor output value Gc (for example, This is a change in acceleration / deceleration generated in the vehicle by travel control such as travel support control).

  Further, in the first embodiment, based on the accelerator operation speed As, the direction of acceleration or deceleration of the vehicle due to the operation state of the driver's accelerator pedal 30 is the same as the direction of acceleration or deceleration of the vehicle due to the correction. In this case, correction of the sensor output value Ga is permitted. On the other hand, when the direction of acceleration or deceleration of the vehicle due to the operation state of the accelerator pedal 30 of the driver is different from the direction of acceleration or deceleration of the vehicle due to the correction, the correction of the sensor output value Ga is prohibited.

  For example, when the driver depresses the accelerator pedal 30 with the intention of acceleration, the accelerator operation speed As (the differential value of the accelerator operation amount AC) becomes a positive value and the vehicle accelerates. In this case, when the vehicle is accelerated by the control using the corrected sensor output value Gc, the correction of the sensor output value Ga is permitted. On the other hand, when the vehicle decelerates by the control using the corrected sensor output value Gc, the correction of the sensor output value Ga is prohibited.

  Further, when the driver intends to decelerate and depresses the accelerator pedal 30, the accelerator operation speed As becomes a negative value and the vehicle decelerates. In this case, when the vehicle decelerates by the control using the corrected sensor output value Gc, the correction of the sensor output value Ga is permitted. On the other hand, when the vehicle is accelerated by control using the corrected sensor output value Gc, correction of the sensor output value Ga is prohibited.

In the first embodiment, an acceleration-side correction driver sensitivity sensitivity term map that is a map of driver sensitivity sensitivity terms when offset correction is performed on the vehicle acceleration side, and a driver when offset correction is performed on the vehicle deceleration side A deceleration-side correction driver sensitivity sensitivity term map, which is a sensitivity sensitivity term map, is stored in advance in the memory.
The acceleration-side correction driver sensitivity sensitivity term map of the first embodiment is a value larger than “0” when the accelerator operation speed As is a positive value, and when the accelerator operation speed As is “0” and a negative value. Is a map having a characteristic of “0”.

Further, the deceleration-side correction driver sensitivity sensitivity term map of the first embodiment is larger than “0” when the accelerator operation speed As is a negative value, and the accelerator operation speed As is “0” and a positive value. In this case, the map has a characteristic of “0”.
Then, when the estimated offset value Gos is a negative value, the driver sensitivity sensitive term calculation unit 104 determines to perform offset correction on the vehicle acceleration side.

Here, in the first embodiment, when the offset estimated value Gos is a negative value, the sensor output value Ga is lower than the true value. In addition, it is assumed that the control that causes the vehicle to accelerate due to this correction is performed by performing correction so that the sensor output value Ga in this state approaches a true value.
Accordingly, when the estimated offset value Gos is a negative value, the driver sensitivity sensitive term calculation unit 104 obtains the driver sensitivity sensitive term Ds corresponding to the accelerator operation speed As from the acceleration side correction driver sensitivity sensitive term map.

On the other hand, when the estimated offset value Gos is a positive value, the driver sensitivity sensitive term calculation unit 104 determines to perform offset correction on the vehicle deceleration side.
Here, in the first embodiment, when the offset estimated value Gos is a positive value, the sensor output value Ga is higher than the true value. In addition, it is assumed that control is performed so that the vehicle is decelerated due to this correction by performing correction so that the sensor output value Ga in this state approaches a true value.

Accordingly, when the estimated offset value Gos is a positive value, the driver sensitivity sensitive term calculation unit 104 acquires the driver sensitivity sensitive term Ds corresponding to the accelerator operation speed As from the deceleration-side corrected driver sensitivity sensitive term map.
The driver sensitivity sensitive term calculation unit 104 inputs the acquired driver sensitivity sensitive term Ds to the correction permission coefficient calculation unit 106.

Here, in the first embodiment, the accelerator operation speed As and the driver sensitivity sensitive term Ds have a relationship that the driver sensitivity sensitive term Ds increases as the accelerator operation speed As increases.
In the first embodiment, the driver sensitivity sensitivity term Ds and the driver sensitivity to the change in vehicle acceleration / deceleration caused by the correction are such that the greater the value of the driver sensitivity sensitivity term Ds, the smaller the sensitivity. The sensitivity is increased as the value of the term Ds is decreased.

The driver sensitivity sensitivity term Ds and the driver sensitivity to changes in vehicle acceleration / deceleration due to the correction are not limited to this relationship. The larger the value of the driver sensitivity sensitivity term Ds, the greater the sensitivity. The relationship may be such that the sensitivity decreases as the value of the term Ds decreases. For example, the driver sensitivity sensitivity value itself may be used as the driver sensitivity sensitivity term Ds.
However, in this case, the limit value of the correction value is proportional to the value of the driver sensitivity sensitive term Ds. That is, the correction value when correcting the sensor output value Ga is limited to a magnitude that is inversely proportional to the magnitude of the driver sensitivity sensitive term Ds.

The correction reliability calculation unit 105 calculates the steering angle θ from the steering angle sensor 6, the vehicle speed V and acceleration estimation value Ge from the acceleration estimation value calculation unit 101, and the offset estimation value Gos from the offset estimation value calculation unit 102. Based on this, a correction reliability Cc used for calculation of a correction permission coefficient Cp described later is calculated.
Here, the correction reliability Cc is a coefficient that depends on the accuracy (accuracy) of the estimated offset value Gos.

In the first embodiment, the correction reliability Cc is, for example, an output value of a map of sensitive terms corresponding to the steering angle θ, the vehicle speed V, the acceleration estimated value Ge, and the offset estimated value Gos, which is created in advance based on experimental data or the like. Is calculated as the product of
Specifically, a map of the steering angle sensitivity term Dθ with respect to the steering angle θ, a map of the vehicle speed sensitivity term Dv with respect to the vehicle speed V, a map of the vehicle acceleration sensitivity term Dg with respect to the acceleration estimation value Ge, and an offset estimation value with respect to the offset estimation value Gos. A map of the sensitive term Dos is created in advance. These maps are stored in advance in a memory (not shown) provided in the sensor output correction device 1. In the first embodiment, the steering angle sensitive term Dθ, the vehicle speed sensitive term Dv, the vehicle acceleration sensitive term Dg, and the offset estimated value sensitive term Dos are set to values in the range of “0 to 1”.

Here, the steering angle sensitive term Dθ increases as the accuracy of the offset estimated value Gos with respect to the magnitude of the steering angle θ increases, and the vehicle speed sensitive term Dv has a higher accuracy of the offset estimated value Gos with respect to the magnitude of the vehicle speed V. It is set to be a large value.
Similarly, the vehicle acceleration sensitivity term Dg increases as the accuracy of the offset estimated value Gos with respect to the magnitude of the acceleration estimated value Ge increases, and the offset estimated value sensitive term Dos becomes the offset estimated value with respect to the magnitude of the offset estimated value Gos. The higher the Gos accuracy, the larger the value.

For example, when the steering angle θ is outside the angle range when the vehicle is traveling straight ahead, the vehicle is likely to be in a turning state or a meandering state, and the accuracy of the offset estimated value Gos calculated at that time is relatively low. Become. On the other hand, when the steering angle θ is within the range of the straight traveling, the vehicle is likely to be in a straight traveling state, and the accuracy of the offset estimated value Gos calculated at that time is relatively high.
Therefore, the steering angle sensitive term Dθ is set to a large value (for example, “1”) in a preset angle range during straight traveling, and is set to a small value (for example, “0”) outside the angle range during straight traveling. Set.

Further, whether the vehicle speed V is too slow or too fast, the accuracy of the calculated offset estimated value Gos is relatively low. Therefore, the vehicle speed sensitivity term Dv is set to a large value (for example, “1”) within a predetermined vehicle speed range in which the influence of the vehicle speed V is allowable, and a small value (for example, “0”) outside the vehicle speed range. Set to.
Further, the accuracy of the offset estimated value Gos is affected by the vehicle weight M. Specifically, the accuracy of the estimated offset value Gos decreases as the acceleration estimated value Ge calculated using the vehicle weight M increases in the positive and negative directions. Therefore, the vehicle acceleration sensitivity term Dg is set to a large value (for example, “1”) in a predetermined acceleration range (a range centering on acceleration 0) that can accept the influence of the vehicle weight M. A small value (eg, “0”) is set outside the range.

  Further, when the offset estimated value Gos is larger than when the offset estimated value Gos is small, the error of the offset estimated value Gos becomes relatively small with respect to the offset estimated value Gos. Therefore, when the offset estimated value Gos is large, the accuracy of the offset estimated value Gos is improved compared to when the offset estimated value Gos is small. Therefore, the offset estimated value sensitivity term Dos is set to a small value (for example, “0”) in a preset range of the offset estimated value Gos that cannot allow the relative error (a range centered on the offset estimated value 0). Outside this range, a value that increases toward the outside (0 <Dos ≦ 1) is set.

The correction reliability calculation unit 105 performs steering angle sensitive term Dθ, vehicle speed sensitive term Dv, vehicle acceleration sensitive term Dg, and offset estimated value sensitive to the input steering angle θ, vehicle speed V, acceleration estimated value Ge, and offset estimated value Gos. Based on the term Dos, the correction reliability Cc is calculated according to the following equation (3).
Cc = Dθ × Dv × Dg × Dos (3)

  That is, the correction reliability calculation unit 105 calculates the steering angle sensitivity term Dθ, the steering angle sensitivity term Dθ, the vehicle speed sensitivity term Dv, the vehicle acceleration sensitivity term Dg, and the offset estimated value sensitivity term Dos as shown in the above equation (3). By multiplying, the correction reliability Cc is calculated. Since each of these sensitive terms has a value in the range of “0 to 1”, the correction reliability Cc also has a value in the range of “0 to 1”. The correction reliability Cc increases as the values of the vehicle speed sensitivity term Dv, the vehicle acceleration sensitivity term Dg, and the offset estimated value sensitivity term Dos increase.

The correction reliability calculation unit 105 inputs the calculated correction reliability Cc to the correction permission coefficient calculation unit 106.
Based on the driver sensitivity sensitivity term Ds from the driver sensitivity sensitivity term calculation unit 104 and the correction reliability Cc from the correction reliability calculation unit 105, the correction permission coefficient calculation unit 106 performs a correction permission coefficient according to the following equation (4). Cp is calculated.
Cp = Ds × Cc (4)
That is, the correction permission coefficient calculation unit 106 calculates the correction permission coefficient Cp by multiplying the driver sensitivity sensitivity term Ds by the correction reliability Cc.
Therefore, the greater the correction reliability Cc, the greater the contribution of the driver sensitivity sensitive term Ds to the correction permission coefficient Cp.

The correction permission coefficient calculation unit 106 inputs the calculated correction permission coefficient Cp to the correction value restriction unit 107.
The correction value limiting unit 107 calculates a correction value for correcting the sensor output value Ga based on the correction permission coefficient Cp from the correction permission coefficient calculating unit 106. At that time, the correction value limiting unit 107 of the first embodiment limits the correction value without immediately setting the correction value when correcting the sensor output value Ga to a value that cancels the offset estimated value Gos. ing.

That is, the correction value limiting unit 107 changes the correction value from a preset initial value (for example, “0”) to a value that cancels the estimated offset value Gos that is the upper limit value. At this time, the correction value limiting unit 107 limits the correction value change rate Ci to a value based on the correction permission coefficient Cp.
Specifically, as indicated by the time change L501 of the correction permission coefficient Cp and the time change L502 of the rate limiter constant RL in FIG. 4, the correction value limiting unit 107 is a rate limiter constant proportional to the input correction permission coefficient Cp. RL is calculated.

  Then, the change rate (increase rate) Ci of the correction value is limited based on the calculated rate limiter constant RL. That is, as indicated by the time variation L503 of the limit correction value CL in FIG. 4, the correction rate increase rate Ci increases (the limit amount decreases) as the rate limiter constant RL increases, and the rate limiter constant RL decreases. The increase rate Ci of the correction value is decreased (the limit amount is increased).

In the example of FIG. 4, at the time t1, the rate limiter constant RL before the time t1 is smaller than the rate limiter constant RL before the time t1. Therefore, as shown in FIG. 4, the increase rate Ci1 before time t1 and the increase rate Ci2 before time t1 in the same change time Δt have a relationship of “Ci1> Ci2.”
This is equivalent to increasing the correction value increase rate Ci as the correction permission coefficient Cp is larger, and decreasing the correction value increase rate Ci as the correction permission coefficient Cp is smaller.

Here, as shown in the above equation (4), the correction permission coefficient Cp is a product of the driver sensitivity sensitive term Ds and the correction reliability Cc.
Therefore, when the driver is sensitive to changes in the acceleration / deceleration of the vehicle due to the correction of the sensor output value Ga (the driver sensitivity sensitivity term Ds is small) or the accuracy of the offset estimated value Gos is low. The increase rate Ci becomes smaller. That is, even if the driver sensitivity sensitive term Ds is large, the increase rate Ci is small when the accuracy of the offset estimated value Gos is low.

On the other hand, when the driver is insensitive to changes in the vehicle acceleration / deceleration due to the correction of the sensor output value Ga (the driver sensitivity sensitivity term Ds is large), and the accuracy of the offset estimated value Gos is high, the increase rate Ci is large. Become.
When the correction permission coefficient Cp is “0”, the correction value limiting unit 107 inputs the preset initial value (for example, “0”) of the correction value CL to the output value correction unit 108. When the correction permission coefficient Cp becomes a value larger than “0”, a new value obtained by increasing the initial value or the previous correction value CL by the increase rate Ci calculated by the rate limiter constant RL proportional to the input correction permission coefficient Cp. A correct correction value CL is calculated. The correction value restriction unit 107 inputs the calculated correction value CL (hereinafter referred to as “restriction correction value CL”) to the output value correction unit 108. The correction value limiting unit 107 sets a value (for example, the offset estimated value Gos itself) that cancels the offset estimated value Gos as the upper limit value of the limited correction value CL.

  The output value correction unit 108 includes an adder, and adds the limit correction value CL input from the correction value limit unit 107 to the sensor output value Ga input from the acceleration sensor 2, thereby obtaining a sensor output value. Ga is corrected. The output value correcting unit 108 uses the sensor output value Gc after correction (hereinafter referred to as “corrected sensor output value Gc”) for each control unit that uses the output value of the acceleration sensor 2 such as the driving support device 20 for control. Supply.

(Sensor output value correction processing)
Next, the processing procedure of the sensor output correction process executed in the controller 10 will be described based on FIG. The sensor output correction process is repeatedly executed at a preset period.
When the sensor output correction process is started in the controller 10, first, the process proceeds to step S201.
In step S201, the acceleration estimated value calculation unit 101 calculates the estimated value Ge of the vehicle acceleration, inputs the calculated acceleration estimated value Ge to the offset estimated value calculation unit 102, and proceeds to step S202.

  Specifically, the acceleration estimated value calculation unit 101 calculates the vehicle speed V of the vehicle based on the wheel speeds Vh1 to Vh4 from the wheel speed sensor 5, and multiplies the calculated square value of the vehicle speed V by a fixed gain K set in advance. Thus, the running resistance R is calculated. Then, according to the above equation (1), the running resistance R is subtracted from the vehicle torque estimation value Te from the driving torque estimation unit 100, and the subtraction result is divided by the vehicle weight M to calculate the acceleration estimation value Ge.

  In step S202, the offset estimated value calculation unit 102 subtracts the sensor output value Ga from the acceleration sensor 2 from the acceleration estimated value Ge from the acceleration estimated value calculation unit 101 according to the above equation (2), thereby estimating the offset. The value Gos is calculated. Then, the calculated offset estimated value Gos is input to the driver sensitivity sensitive term calculation unit 104, the correction reliability calculation unit 105, and the correction value restriction unit 107, respectively, and the process proceeds to step S203.

In step S203, the driver sensitivity sensitive term calculation unit 104 calculates the driver sensitivity sensitive term Ds based on the estimated offset value Gos from the driver sensitivity sensitive term calculation unit 104 and the accelerator operation speed As from the operation state detection unit 103. Thereafter, the process proceeds to step S204.
Specifically, the driver sensitivity sensitive term calculation unit 104 selects a map corresponding to the sign of the estimated offset value Gos from the acceleration-side corrected driver sensitivity sensitive term map or the deceleration-side corrected driver sensitivity sensitive term map. Then, the driver sensitivity sensitive term Ds corresponding to the input accelerator operation speed As is acquired from the selected map, and the acquired driver sensitivity sensitive term Ds is input to the correction permission coefficient calculating unit 106.

In step S204, the correction reliability calculation unit 105 calculates the correction reliability Cc, inputs the calculated correction reliability Cc to the correction permission coefficient calculation unit 106, and proceeds to step S205.
Specifically, the correction reliability calculation unit 105 acquires the steering angle sensitive term Dθ corresponding to the steering angle θ input from the steering angle sensor 6 from the steering angle sensitive term map, and estimates the acceleration from the vehicle speed sensitive term map. A vehicle speed sensitive term Dv corresponding to the vehicle speed V input from the value calculation unit 101 is acquired. In addition, the vehicle acceleration sensitive term Dg corresponding to the acceleration estimated value Ge input from the acceleration estimated value calculating unit 101 is obtained from the vehicle acceleration sensitive term map, and the offset estimated value calculating unit 102 is obtained from the offset estimated value sensitive term map. The offset estimated value sensitive term Dos corresponding to the offset estimated value Gos input from is acquired. Then, according to the above equation (3), the obtained steering angle sensitivity term Dθ, vehicle speed sensitivity term Dv, vehicle acceleration sensitivity term Dg and offset estimated value sensitivity term Dos are respectively multiplied to calculate a correction reliability Cc.

In step S <b> 205, in the correction permission coefficient calculation unit 106, the driver sensitivity sensitive term Ds input from the driver sensitivity sensitive term calculation unit 104 and the correction reliability input from the correction reliability calculation unit 105 according to the above equation (4). The correction permission coefficient Cp is calculated by multiplying by Cc. Then, the calculated correction permission coefficient Cp is input to the correction value limiting unit 107, and the process proceeds to step S206.
In step S206, the correction value limiting unit 107 sets the limit correction value CL based on the correction permission coefficient Cp input from the correction permission coefficient calculation unit 106 and the offset estimation value Gos input from the offset estimation value calculation unit 102. calculate. Then, the calculated limit correction value CL is input to the output value correction unit 108, and the process proceeds to step S207.

Here, the correction value limiting unit 107 calculates a rate limiter constant RL that is proportional to the input correction permission coefficient Cp. Then, an increase rate Ci of the correction value CL is calculated based on the calculated rate limiter constant RL, and an addition amount corresponding to the calculated increase rate Ci is added to the initial value or the previous limit correction value CL to obtain a new limit correction value. CL is calculated. The correction value limiting unit 107 calculates the limit correction value CL using a value (for example, the offset estimated value Gos itself) that cancels the offset estimated value Gos as an upper limit value. The correction value restriction unit 107 inputs the calculated restriction correction value CL to the output value correction unit 108.
In step S207, the output value correction unit 108 calculates the corrected sensor output value Gc by adding the limit correction value CL input from the correction value limiting unit 107 to the sensor output value Ga input from the acceleration sensor 2. To do. Then, the calculated sensor output value Gc after correction is supplied to various control units such as the driving support device 20 and the series of processes is completed.

(Operation)
Next, the operation of the sensor output correction device 1 of the first embodiment will be described.
When the ignition switch is turned on and power is supplied to the sensor output correction device 1, detection of various vehicle states is started by various sensors. Various detection results are supplied to the controller 10.
That is, the accelerator operation amount AC from the accelerator sensor 3, the sensor output value Ga from the acceleration sensor 2, the wheel speeds Vh1 to Vh4 from the wheel speed sensor 5, and the motor current Im from the motor current sensor 7 are supplied to the controller 10. . In addition, the steering angle θ from the steering angle sensor 6 is supplied to the controller 10.
In the controller 10, the drive torque estimation unit 100 calculates the estimated torque value Te using the drive torque observer based on the input motor current Im and the wheel speeds Vh1 to Vh2 of the drive wheels 13RR and 13RL. The drive torque estimating unit 100 inputs the calculated torque estimated value Te to the acceleration estimated value calculating unit 101.

  On the other hand, the estimated acceleration calculation unit 101 calculates the vehicle speed V based on the input wheel speeds Vh1 to Vh4. Further, the square value of the vehicle speed V is calculated, and the running resistance R is calculated by multiplying the square value by a fixed gain K. Then, the estimated acceleration value Ge is calculated by dividing the subtraction result obtained by subtracting the running resistance R from the input estimated torque value Te by the vehicle weight M. The acceleration estimated value calculation unit 101 inputs the calculated acceleration estimated value Ge to the offset estimated value calculation unit 102 and the correction reliability calculation unit 105, respectively (step S201).

  The offset estimated value calculation unit 102 subtracts the sensor output value Ga input from the acceleration sensor 2 from the acceleration estimated value Ge input from the acceleration estimated value calculation unit 101 to calculate the offset estimated value Gos. Then, the calculated offset estimated value Gos is input to the driver sensitivity sensitive term calculation unit 104, the correction reliability calculation unit 105, and the correction value restriction unit 107, respectively (step S202).

Further, the operation state detecting unit 103 calculates the accelerator operation speed As by differentiating the accelerator operation amount AC input from the accelerator sensor 3. Then, the calculated accelerator operation speed As is input to the driver sensitivity sensitive term calculation unit 104.
If the input offset estimated value Gos is a negative value, the driver sensitivity sensitive term calculation unit 104 is input from the acceleration-side corrected driver sensitivity sensitive term map having the characteristics indicated by the solid line L301 in FIG. A driver sensitivity sensitive term Ds corresponding to the accelerator operation speed As is acquired. As shown in FIG. 6, the driver sensitivity sensitivity term Ds when correcting the sensor output value Ga to the acceleration side becomes a value that increases linearly as the accelerator operation speed As increases in the positive direction (as the depression speed increases). Is set. On the other hand, “0” is set for a change in the negative direction of the accelerator operation speed As.

  On the other hand, when the input offset estimated value Gos is a positive value, the driver sensitivity sensitive term calculation unit 104 inputs from the deceleration-side corrected driver sensitivity sensitive term map having the characteristics indicated by the broken line L302 in FIG. The driver sensitivity sensitive term Ds corresponding to the accelerator operation speed As thus obtained is acquired. As shown in FIG. 6, the driver sensitivity sensitivity term Ds when correcting the sensor output value Ga to the deceleration side increases as the accelerator operation speed As increases in the negative direction (relaxes the pedal (releases the foot)). ) It is set to a value that increases linearly. On the other hand, “0” is set for the positive change in the accelerator operation speed As.

Then, the driver sensitivity sensitive term calculation unit 104 inputs the acquired driver sensitivity sensitive term Ds to the correction permission coefficient calculation unit 106 (step S203).
Further, the correction reliability calculation unit 105 acquires a steering angle sensitive term Dθ corresponding to the steering angle θ input from the steering angle sensor 6 from the steering angle sensitive term map having the characteristics shown in FIG. As shown in FIG. 7A, the steering angle sensitive term map is set to have a value in a range of “0 <Dθ ≦ 1” in a range of −θd to + θd that is a predetermined steering angle range. Yes. Specifically, the value changes steeply and linearly from “−θd” toward “0” toward the maximum value “1”, and then becomes constant at “1” toward + θd, and is steep and linear from immediately before + θd. Changes toward the minimum value “0”. Further, outside the range of −θd to + θd, the minimum value “0” is constant.

  Subsequently, the correction reliability calculation unit 105 acquires a vehicle speed sensitivity term Dv corresponding to the vehicle speed V input from the acceleration estimated value calculation unit 101 from the vehicle speed sensitivity term map having the characteristics shown in FIG. As shown in FIG. 7B, the vehicle speed sensitive term map is set to have a value in the range of “0 <Dv ≦ 1” in the range of V1 to V2, which is a preset vehicle speed range. Specifically, the vehicle speed changes steeply and linearly toward the maximum value “1” from the vehicle speed V1 to V2, and then becomes constant “1” toward the V2 and is steeply and linearly minimum immediately before V2. It changes toward “0”. Further, outside the range of V1 to V2, it is constant at the minimum value “0”.

  Subsequently, the correction reliability calculation unit 105 calculates the vehicle acceleration sensitivity term Dg corresponding to the acceleration estimated value Ge input from the acceleration estimated value calculation unit 101 from the vehicle acceleration sensitivity term map having the characteristics shown in FIG. get. As shown in FIG. 7C, the vehicle acceleration sensitivity term map is set to a value in the range of “0 <Dg ≦ 1” in the range of −Ged to + Ged which is a range of preset acceleration estimation values. Is set. Specifically, the value changes steeply and linearly from “-Ged” toward “0” toward the maximum value “1”, then becomes constant at “1” toward + Ged, and is steep and linear from immediately before + Ged. Changes toward the minimum value “0”. Further, outside the range of −Ged to + Ged, the minimum value “0” is constant.

  Subsequently, the correction reliability calculation unit 105 calculates the offset estimated value sensitive term corresponding to the offset estimated value Gos input from the offset estimated value calculating unit 102 from the offset estimated value sensitive term map having the characteristics shown in FIG. Get Dos. As shown in FIG. 7D, the offset estimated value sensitive term map has a value in the range of “0 ≦ Dos <1” in the range of −Gosd to + Gosd which is a preset range of the offset estimated value Gos. Is set to Specifically, the value changes steeply and linearly toward the minimum value “0” from −Gosd to “0”, then becomes constant at “0” toward + Gosd, and is steep and linear from immediately before + Gosd. Changes toward the maximum value “1”. Further, outside the range of -Gosd to + Gosd, the maximum value “1” is constant.

Then, the correction reliability calculation unit 105 multiplies the obtained steering angle sensitivity term Dθ, vehicle speed sensitivity term Dv, vehicle acceleration sensitivity term Dg, and offset estimated value sensitivity term Dos according to the above equation (3) to obtain the correction reliability. The degree Cc is calculated. The correction reliability calculation unit 105 inputs the calculated correction reliability Cc to the correction permission coefficient calculation unit 106 (step S204).
The correction permission coefficient calculation unit 106 multiplies the driver sensitivity sensitivity term Ds input from the driver sensitivity sensitivity term calculation unit 104 by the correction reliability Cc input from the correction reliability calculation unit 105, thereby correcting the correction permission coefficient Cp. Is calculated. Then, the correction permission coefficient calculation unit 106 inputs the calculated correction permission coefficient Cp to the correction value restriction unit 107 (step S205).

The correction value limiting unit 107 first calculates a rate limiter constant RL that is proportional to the correction permission coefficient Cp input from the correction permission coefficient calculation unit 106. Next, a limit correction value CL is calculated based on the calculated rate limiter constant RL and the estimated offset value Gos input from the estimated offset value calculation unit 102.
Specifically, a value obtained by adding an addition value corresponding to the rate of change Ci limited by the rate limiter constant RL to the minimum correction value (for example, “0”) or the previous limit correction value CL, Calculated as the limit correction value CL.

Hereinafter, based on FIG. 8, the operation at the time of correcting the sensor output value Ga will be described with reference to a specific example.
As shown by a solid line L601 in FIG. 8, the accelerator operation amount AC is constant and the accelerator operation speed As is “0” until time t1. Therefore, during this period, the driver sensitivity sensitive term Ds is “0”, so that the correction permission coefficient Cp is constant at “0” as indicated by a solid line L602 in FIG.

As a result, as indicated by a solid line L602 in FIG. 8, the limit correction value CL is constant at the minimum value “0”, and the corrected sensor output value Gc output to the driving support device 20 or the like is a solid line in the figure. As indicated by L604 and L605, the value is the same as the sensor output value Ga of the acceleration sensor 2.
Thereafter, as indicated by solid lines L601 and L602 in FIG. 8, the accelerator operation amount AC rapidly increases, and accordingly, the correction permission coefficient Cp rapidly increases until time t2.

When the correction permission coefficient Cp increases rapidly, the increase rate of the correction value also increases rapidly, and the limit correction value CL increases rapidly as indicated by the solid line L603 in FIG.
As a result, as indicated by a solid line L605 in FIG. 8, the corrected sensor output value Gc output to the travel support device 20 or the like rapidly increases.
In other words, during the period from time t1 to t2, the accelerator pedal 30 is depressed at a relatively large accelerator operation speed As, and the driver can change the acceleration / deceleration of the vehicle due to the offset correction and depress the accelerator pedal 30. It becomes difficult to distinguish from the change in acceleration / deceleration of the vehicle. In such a period, by increasing the correction value, the speed of convergence to the true value is ensured while suppressing the driver from feeling uncomfortable with changes in the vehicle acceleration / deceleration caused by the correction.

Subsequently, during the period from time t2 to time t3, as shown by a solid line L601 in FIG. 8, the accelerator operation amount AC increases gently, and the accelerator operation speed As decreases. As a result, as indicated by solid lines L602 and L603 in FIG. 8, the correction permission coefficient Cp decreases rapidly, and the increase rate of the limit correction value CL also decreases rapidly with this.
As a result, as indicated by a solid line L605 in FIG. 8, the corrected sensor output value Gc output to the travel support device 20 or the like is gently increased.

  That is, during the period from time t2 to t3, the accelerator pedal 30 is depressed at a relatively small accelerator operation speed As, and the driver is sensitive to changes in the acceleration / deceleration of the vehicle due to offset correction. In such a period, by reducing the correction amount, the driver's uncomfortable feeling with respect to the change in the acceleration / deceleration of the vehicle due to the correction is suppressed.

Subsequently, in the period from time t3 to t4, as indicated by a solid line L601 in FIG. 8, the accelerator operation amount AC becomes constant, and thereafter, the accelerator operation amount AC decreases. In this period, the accelerator operation speed As is “0” or a negative value.
Here, since the estimated offset value Gos is a negative value, the driver sensitivity sensitive term map at the time of acceleration side correction is used to calculate the driver sensitivity sensitive term Ds. As shown in FIG. 6, in the acceleration-side correction driver sensitivity sensitive term map of the first embodiment, the driver sensitivity sensitive term Ds becomes “0” when the accelerator operation speed As is “0” or a negative value.

Therefore, in the period from time t3 to t4, as indicated by the solid lines L602 and L603 in FIG. 8, the correction permission coefficient Cp is constant at “0”, so the value immediately before the limit correction value CL becomes “0”. (The increase rate Ci becomes “0”).
As a result, as indicated by a solid line L605 in FIG. 8, the corrected sensor output value Gc output to the driving support device 20 or the like becomes constant.

Thereafter, during the period from time t3 to time t4, as indicated by the solid line L601 in FIG. 8, the accelerator operation amount AC increases, so the accelerator operation speed As becomes a positive value. Accordingly, as indicated by solid lines L602 and L603 in FIG. 8, the correction permission coefficient Cp becomes larger than “0”, the limit correction value CL increases, and converges to the offset estimated value Gos.
As a result, as indicated by a solid line L605 in FIG. 8, the corrected sensor output value Gc output to the driving support device 20 or the like approaches the sensor output true value Gt that is the true value of the sensor output value.

After time t4, the limit correction value CL is constant at the offset estimated value Gos as shown by the solid line L603 in FIG. 8, and therefore, output to the driving support device 20 and the like as shown by the solid line L605 in FIG. The corrected sensor output value Gc is constant at the sensor output true value Gt.
Conventionally, as shown in FIG. 9, when the accelerator operation amount AC is constant (when traveling on a straight road at a constant speed), in order to prevent the driver from feeling uncomfortable due to a sudden change in acceleration / deceleration due to correction, Offset correction was performed while gradually increasing the correction value with a relatively small increase value indicated by the middle D701.
On the other hand, in the sensor output correction device 1 according to the first embodiment, as shown by D702 in FIG. 9, the increase value of the correction value is increased as compared with the conventional case according to the accelerator operation speed As of the driver. It becomes possible to enlarge. As a result, the offset correction can be performed relatively quickly while suppressing the occurrence of the driver's uncomfortable feeling due to the sudden change in the acceleration / deceleration due to the correction.

  Here, the acceleration sensor 2 corresponds to an acceleration sensor. The drive torque estimation unit 100 corresponds to the drive torque estimation unit. The acceleration estimated value calculation unit 101 corresponds to the acceleration estimated value calculation unit. The offset estimated value calculation unit 102 corresponds to the offset estimated value calculation unit. The operation state detection unit 103 corresponds to the operation state detection unit. The driver sensitivity sensitive term calculation unit 104 corresponds to a driver sensitivity sensitive value setting unit. The correction reliability calculation unit 105 corresponds to the correction reliability calculation unit. The correction value limiting unit 107 corresponds to the correction value limiting unit. The output value correction unit 108 corresponds to the output value correction unit. The sensitivity of the driver to the change in the acceleration / deceleration of the vehicle due to the correction of the sensor output value Ga, which changes according to the operation state of the accelerator pedal 30, corresponds to the driver sensitivity sensitivity value. The accelerator pedal 30 corresponds to an accelerator operator.

(Effect of 1st Embodiment)
(1) The acceleration sensor 2 detects the acceleration of the vehicle. The offset estimated value calculation unit 102 calculates an offset estimated value Gos that is an estimated value of the offset value of the acceleration sensor 2. The output value correction unit 108 performs correction by adding the correction value to the sensor output value Ga so as to cancel the offset estimated value Gos. The operation state detection unit 103 detects an operation state (for example, an accelerator operation speed As) of a braking / driving force instruction operator (for example, an accelerator pedal 30) that instructs a braking / driving force of the vehicle. Based on the detected operation state, the driver sensitivity sensitive term calculation unit 104 determines the sensitivity of the driver to acceleration or deceleration of the vehicle caused by travel control using the corrected value of the sensor output value Ga (corrected sensor output value Gc). This is a value indicating the magnitude, and the direction of acceleration or deceleration of the vehicle caused by the operation of the braking / driving force indicating operator is the same as the direction of acceleration or deceleration of the vehicle caused by the travel control using the corrected sensor output value Gc. When the direction of the driver is in the direction, the driver's sensitivity sensitivity decreases as the operating state of the braking / driving force indicating operator becomes an operating state in which the rate of change in the acceleration / deceleration of the vehicle increases (for example, the accelerator operating speed As increases). A driver sensitivity sensitive term Ds which is an index value of the value is set. The correction value restriction unit 107 restricts the magnitude of the correction value when the output value correction unit 108 corrects the sensor output value Ga based on the driver sensitivity sensitivity term Ds set based on the operation state. The correction value limiting unit 107 limits the magnitude of the correction value so that the change in the sensor output value Ga decreases as the driver sensitivity sensitivity term Ds changes in the direction in which the sensitivity sensitivity value of the driver increases.

  With this configuration, the driver sensitivity sensitivity term Ds decreases as the driver sensitivity sensitivity value increases, and the driver sensitivity sensitivity term Ds increases as the driver sensitivity sensitivity value decreases. The sensor output value Ga can be corrected with the limit correction value CL. In other words, the limit value of the correction value can be increased in situations where the driver is likely to feel uncomfortable with changes in the vehicle acceleration / deceleration caused by the correction, and the limit value of the correction value can be decreased in situations where the driver is less likely to feel discomfort. It becomes.

  As a result, it is possible to make it difficult for the driver to distinguish between a change in the acceleration / deceleration of the vehicle due to his own operation and a change in the acceleration / deceleration of the vehicle due to the offset correction, and also due to the offset correction. It becomes possible to change the magnitude of the correction value in accordance with the magnitude of the driver's sensitivity to changes in the vehicle acceleration / deceleration. Therefore, it is possible to improve the convergence speed of the sensor output value to the true value while suppressing the driver from feeling uncomfortable with the vehicle acceleration / deceleration change caused by the offset correction.

(2) The drive torque estimating unit 100 calculates an estimated torque Te that is an estimated value of the drive torque of the vehicle. The estimated acceleration value calculation unit 101 calculates an estimated acceleration value Ge, which is an estimated value of acceleration of the vehicle, based on the estimated torque value Te. The estimated offset value calculation unit 102 subtracts the sensor output value Ga of the acceleration sensor 2 from the estimated acceleration value Ge to calculate the estimated offset value Gos.
With this configuration, it is possible to calculate the offset estimated value Gos of the sensor output value Ga regardless of the traveling state of the vehicle (for example, traveling straight on a flat road at a constant speed). As a result, the offset correction based on the driver sensitivity sensitive term Ds can be performed at an appropriate timing.

(3) The correction value limiting unit 107 changes the correction value CL when the output value correction unit 108 corrects the sensor output value Ga from a preset initial value to a value that cancels the offset estimated value Gos. The change rate Ci of the correction value CL is reduced as the driver sensitivity sensitivity term Ds changes in the direction in which the driver sensitivity sensitivity value increases.
With this configuration, the change rate Ci of the correction value of the sensor output value Ga can be limited in accordance with the magnitude of the driver sensitivity sensitive term Ds, so that the driver sensitivity sensitive term Ds acts as a rate limiter. It becomes possible to make it.
As a result, it is possible to appropriately correct various driving situations and driver operations without causing the driver to feel uncomfortable.

(4) When the correction value limiting unit 107 has the same acceleration or deceleration direction of the vehicle due to the operation state of the braking / driving force indicator operator and the acceleration or deceleration direction of the vehicle due to the correction, the sensor output The correction of the value Ga is permitted, and the correction of the sensor output value Ga is prohibited when the direction of acceleration or deceleration of the vehicle due to the operation state of the driver is different from the direction of acceleration or deceleration of the vehicle due to the correction. .
In this configuration, for example, it is assumed that the driver operates the braking / driving force instruction operator so that the vehicle accelerates (for example, the accelerator pedal 30 is depressed). In addition, it is assumed that the sensor output value Ga is corrected by the correction value CL limited by the driver sensitivity sensitive term Ds corresponding to the operation state. In such a situation, the correction can be permitted when the corrected sensor output value Gc changes in the direction of accelerating the vehicle.

On the other hand, for example, it is assumed that the driver operates the braking / driving force instruction operator so that acceleration is generated. In addition, it is assumed that the sensor output value is corrected by the correction value CL limited by the driver sensitivity sensitive term Ds corresponding to the operation state. Under such circumstances, the correction can be prohibited when the corrected sensor output value Gc changes in the direction of decelerating the vehicle.
As a result, it is possible to perform offset correction without violating the acceleration / deceleration response that the driver expects for his own operation.

(5) The operation state detection unit 103 detects the operation speed (for example, the accelerator operation speed As) of the braking / driving force instruction operator (for example, the accelerator pedal 30). The driver sensitivity sensitive term Ds is set to a value that decreases the limit amount as the operating speed of the braking / driving force indicating operator increases.
Here, the sensitivity to the acceleration / deceleration of the driver decreases as the operation speed of the driver increases.
Based on this, the driver sensitivity sensitivity term Ds is set to a value that increases the correction value (decreases the limit amount) as the operation speed of the driver increases. As a result, more corrections can be performed without giving the driver a sense of incongruity, and the convergence speed of the sensor output value to the true value can be further improved.

(6) The correction reliability calculation unit 105 determines whether the estimated offset value Gos is based on at least one of the vehicle state (for example, the steering angle θ, the vehicle speed V, etc.), the estimated acceleration value Ge, and the estimated offset value Gos. A correction reliability Cc, which is a dependent coefficient, is calculated. The correction value limiting unit 107 limits the correction value CL so that the limit amount decreases as the correction reliability Cc increases.
With this configuration, the limit amount of the correction value CL can be controlled by the reliability (accuracy) of the offset estimated value Gos.
As a result, it is possible to improve both the accuracy of offset correction and the speed of offset correction.

(7) The correction reliability calculation unit 105 calculates the correction reliability Cc based on at least the acceleration estimation value Ge, and the correction reliability Cc is a value that increases the limit value of the correction value CL as the acceleration estimation value Ge increases. Was set to.
Here, the accuracy of the offset estimation value is affected by the vehicle weight M, and the influence of the vehicle weight M increases as the value of the offset estimation value increases.
Based on this, the correction reliability Cc is set to a value that decreases as the estimated acceleration value Ge increases.
As a result, it is possible to perform offset correction in consideration of the influence of the vehicle weight M on the offset estimated value Gos, and it is possible to improve both the accuracy of offset correction and the speed of offset correction at a higher level. .

(8) The correction reliability calculation unit 105 calculates the correction reliability Cc based on at least the offset estimated value Gos, and the correction reliability Cc is a value that decreases the limit amount of the correction value CL as the offset estimated value Gos increases. Was set to.
Here, when the offset estimated value Gos is large compared to when the offset estimated value Gos is small, the error of the offset estimated value becomes relatively small with respect to the offset estimated value, so the reliability of the offset estimated value is improved. .
Based on this, the correction reliability Cc is set to a value that increases the correction value CL as the offset estimated value Gos increases (a value that reduces the limit amount).
As a result, it is possible to improve both the accuracy of offset correction and the speed of offset correction at a higher level.

(9) The braking / driving force instruction operator includes the accelerator pedal 30. The driver sensitivity sensitive term Ds is set to a value that changes according to the operation state of the accelerator pedal 30 of the driver.
With this configuration, the sensor output value Ga can be corrected with an appropriate correction value CL according to the operation state of the accelerator pedal 30 of the driver.
As a result, it is possible to make it difficult for the driver to distinguish between a change in the vehicle acceleration / deceleration due to his / her accelerator operation and a change in the vehicle acceleration / deceleration due to the offset correction, and the driver sensitivity sensitivity term. The correction amount can be changed according to the magnitude of Ds. For this reason, it is possible to improve the convergence speed of the sensor output value to the true value while suppressing the occurrence of the driver's uncomfortable feeling with respect to the vehicle acceleration / deceleration change caused by the correction.

(Second Embodiment)
(Constitution)
In the second embodiment, the operation state detection unit 103 calculates the required braking force Gb corresponding to the brake operation amount BR based on the brake operation amount BR from the brake sensor 4, and the change speed (change) of the required braking force Gb. The point of detecting (rate) ΔGb is different from the first embodiment. In addition, the sensor output correction device 1 changes according to the change speed (change rate) ΔGb of the required braking force Gb, and the driver sensitivity index value for the change in the vehicle acceleration / deceleration due to the correction of the sensor output value Ga. This is different from the first embodiment in that a map of the driver sensitivity response term Ds is provided. Further, the driver sensitivity sensitive term calculation unit 104 is different from the first embodiment in that the driver sensitivity sensitive term Ds corresponding to the input change speed ΔGb is acquired from the driver sensitivity sensitive term map.

Hereinafter, the same components as those in the first embodiment are denoted by the same reference numerals, description thereof will be omitted as appropriate, and different portions will be described in detail.
As shown in FIG. 10, in the second embodiment, the brake operation amount BR detected by the brake sensor 4 is supplied to the controller 10.
The operation state detection unit 103 according to the second embodiment first calculates the required braking force Gb based on the brake operation amount BR input from the brake sensor 4. Specifically, the required braking force Gb corresponding to the input brake operation amount BR is acquired from a map of the required braking force Gb with respect to the brake operation amount BR stored in advance in a memory (not shown) provided in the controller 10. Next, the operation state detection unit 103 calculates the change speed ΔGb of the requested braking force Gb by differentiating the acquired requested braking force Gb. The operation state detection unit 103 inputs the calculated change speed ΔGb to the driver sensitivity sensitive term calculation unit 104.

The driver sensitivity response term calculation unit 104 according to the second embodiment is based on the estimated offset value Gos input from the estimated offset value calculation unit 102 and the change speed ΔGb of the required braking force Gb input from the operation state detection unit 103. A driver sensitivity sensitive term Ds is calculated.
Here, the driver sensitivity response term Ds of the second embodiment changes according to the change speed ΔGb of the required braking force Gb due to the operation of the brake pedal 32, and the driver responds to the change in acceleration / deceleration due to the correction of the sensor output value Ga. This is an index value of a driver sensitivity sensitivity value that is a value indicating the magnitude of the sensitivity. In addition, the change speed | rate of request | requirement braking force becomes large, so that the operation speed of the driver's brake pedal 32 is large.

  In the second embodiment, the driver sensitivity sensitivity value is the vehicle acceleration or deceleration direction caused by the change speed of the required braking force Gb due to the operation of the brake pedal 32 and the vehicle acceleration caused by the correction of the sensor output value Ga. Alternatively, when the deceleration direction is the same, the rate of decrease of the vehicle acceleration / deceleration due to the change rate of the required braking force Gb due to the operation of the brake pedal 32 increases. In other words, the driver sensitivity sensitivity value of the second embodiment becomes smaller as the operation state of the brake pedal 32 is the operation state in which the rate of change of the acceleration / deceleration of the vehicle is larger.

  When the change speed (brake operation speed) of the required braking force Gb is large, the sensitivity of the driver to the acceleration / deceleration of the vehicle is relatively small, and when the change speed is small, the sensitivity of the driver to the acceleration / deceleration of the vehicle is relatively large. That is, the driver's acceleration / deceleration speed change due to the correction of the sensor output value Ga, which occurs when the driver's acceleration / deceleration sensitivity is small, is difficult for the driver to feel. The sensitivity of becomes smaller. On the other hand, the change in the vehicle acceleration / deceleration caused by the correction of the sensor output value Ga, which occurs when the driver's vehicle acceleration / deceleration sensitivity is high, is easily felt by the driver. The sensitivity of increases.

  Based on this, in the second embodiment, for example, data of sensitivity to acceleration / deceleration change resulting from the above-described correction of an unspecified number of drivers with respect to the change rate of braking force due to operation of the brake pedal 32, obtained by experiment. From this, a map of the driver sensitivity response term is created in advance. The map created in this way is stored in advance in a memory (not shown) provided in the sensor output correction device 1.

  In the second embodiment, based on the change speed ΔGb, the direction of acceleration or deceleration of the vehicle caused by the change in the braking force caused by the driver's operation of the brake pedal 32 and the direction of acceleration or deceleration of the vehicle caused by the correction Is corrected, the correction of the sensor output value Ga is permitted. On the other hand, when the direction of acceleration or deceleration of the vehicle due to the change state of the braking force due to the operation of the brake pedal 32 by the driver is different from the direction of acceleration or deceleration of the vehicle due to the correction, the correction of the sensor output value Ga is performed. Is prohibited.

  For example, when the driver depresses the brake pedal 32 in order to decelerate, the change speed ΔGb becomes a positive value and the vehicle decelerates. In this case, correction of the sensor output value Ga is permitted when the vehicle decelerates by control using the corrected sensor output value Gc. On the other hand, when the vehicle is accelerated by control using the corrected sensor output value Gc, the correction of the sensor output value Ga is prohibited.

  If the driver intends to accelerate and loosens the brake pedal 32, the change speed ΔGb becomes a negative value and the vehicle accelerates. In this case, correction of the sensor output value Ga is permitted when the vehicle is accelerated by control using the corrected sensor output value Gc. On the other hand, correction of the sensor output value Ga is prohibited when the vehicle decelerates by control using the corrected sensor output value Gc.

In the second embodiment, as in the first embodiment, the acceleration-side correction driver sensitivity sensitivity term map when offset correction is performed on the vehicle acceleration side, and the offset correction is performed on the vehicle deceleration side. A driver sensitivity response term map for deceleration side correction is prepared for each.
However, the acceleration-side correction driver sensitivity sensitivity term map of the second embodiment is “0” when the change speed ΔGb is “0” and a positive value, and is “0” when the change speed ΔGb is a negative value. It is a map having a characteristic that becomes a larger value.

Further, the deceleration-side correction driver sensitivity sensitivity term map of the second embodiment is “0” when the change speed ΔGb is “0” and a negative value, and is “0” when the change speed ΔGb is a positive value. It is a map having a characteristic that becomes a larger value.
Then, when the estimated offset value Gos is a negative value, the driver sensitivity sensitive term calculation unit 104 determines to perform offset correction on the vehicle acceleration side.

Here, in the second embodiment, when the offset estimated value Gos is a negative value, the sensor output value Ga is lower than the true value. In addition, it is assumed that the control that causes the vehicle to accelerate due to this correction is performed by performing correction so that the sensor output value Ga in this state approaches a true value.
Accordingly, the driver sensitivity sensitive term calculation unit 104 acquires the driver sensitivity sensitive term Ds corresponding to the accelerator operation speed As from the acceleration-side corrected driver sensitivity sensitive term map.

On the other hand, when the estimated offset value Gos is a positive value, the driver sensitivity sensitive term calculation unit 104 determines to perform offset correction on the vehicle deceleration side.
Here, in the second embodiment, when the offset estimated value Gos is a positive value, the sensor output value Ga is higher than the true value. It is assumed that control is performed so that the vehicle decelerates due to this correction by performing correction so that the sensor output value Ga in this state approaches the true value.
Therefore, the driver sensitivity sensitive term calculation unit 104 acquires the driver sensitivity sensitive term Ds corresponding to the accelerator operation speed As from the deceleration-side corrected driver sensitivity sensitive term map.
The driver sensitivity sensitive term calculation unit 104 inputs the acquired driver sensitivity sensitive term Ds to the correction permission coefficient calculation unit 106.

(Operation)
Next, the operation of the sensor output correction apparatus 1 according to the second embodiment will be described.
When the ignition switch is turned on, the brake operation amount BR from the brake sensor 4, the sensor output value Ga from the acceleration sensor 2, the wheel speeds Vh1 to Vh4 from the wheel speed sensor 5, and the motor current Im from the motor current sensor 7 are It is supplied to the controller 10. In addition, the steering angle θ from the steering angle sensor 6 is supplied to the controller 10.
When the brake operation amount BR is input from the brake sensor 4, the operation state detection unit 103 acquires the requested braking force Gb corresponding to the input brake operation amount BR from the map of the requested braking force Gb. Further, the operation state detection unit 103 differentiates the acquired required braking force Gb to calculate a change speed ΔGb of the required braking force Gb. The operation state detection unit 103 inputs the calculated change speed ΔGb to the driver sensitivity sensitive term calculation unit 104.

  If the input offset estimated value Gos is a positive value, the driver sensitivity sensitive term calculation unit 104 receives an input from the deceleration-side corrected driver sensitivity sensitive term map having the characteristics indicated by the broken line L802 in FIG. A driver sensitivity sensitive term Ds corresponding to the change rate ΔGb is acquired. As shown in FIG. 11, the driver sensitivity sensitivity term Ds when correcting the sensor output value Ga to the deceleration side increases linearly as the change speed ΔGb increases in the positive direction (the speed at which the brake pedal 32 is depressed). Is set to a value.

On the other hand, if the input offset estimated value Gos is a negative value, the driver sensitivity sensitive term calculation unit 104 calculates the input from the acceleration correction driver sensitivity sensitive term map having the characteristics indicated by the solid line L801 in FIG. The driver sensitivity sensitive term Ds corresponding to the changed change rate ΔGb is acquired. As shown in FIG. 11, the driver sensitivity sensitivity term Ds when the sensor output value Ga is corrected to the acceleration side is linear as the change speed ΔGb is larger in the negative direction (as the speed of depressing (releasing the foot) is larger). Is set to a large value.
Then, the driver sensitivity sensitive term calculation unit 104 inputs the acquired driver sensitivity sensitive term Ds to the correction permission coefficient calculation unit 106 (step S203).
Subsequent operations are the same as those in the first embodiment, and a description thereof will be omitted.

  Here, the acceleration sensor 2 corresponds to an acceleration sensor. The drive torque estimation unit 100 corresponds to the drive torque estimation unit. The acceleration estimated value calculation unit 101 corresponds to the acceleration estimated value calculation unit. The offset estimated value calculation unit 102 corresponds to the offset estimated value calculation unit. The operation state detection unit 103 corresponds to the operation state detection unit. The driver sensitivity sensitive term calculation unit 104 corresponds to a driver sensitivity sensitive value setting unit. The correction reliability calculation unit 105 corresponds to the correction reliability calculation unit. The correction value limiting unit 107 corresponds to the correction value limiting unit. The output value correction unit 108 corresponds to the output value correction unit. The sensitivity of the driver to the change in the acceleration / deceleration of the vehicle due to the correction of the sensor output value Ga, which changes according to the change speed ΔGb of the required braking force Gb due to the operation of the brake pedal 32, corresponds to the driver sensitivity sensitive value. The brake pedal 32 corresponds to a brake operator.

(Effect of 2nd Embodiment)
This embodiment has the following effects in addition to the effects of the first embodiment.
(1) The braking / driving force instruction operator includes the brake pedal 32. The driver sensitivity sensitive term Ds is set to a value that changes in accordance with the change state (change speed ΔGb) of the braking force (required braking force Gb) due to the driver's operation of the brake pedal 32.
With this configuration, it is possible to correct the sensor output value Ga with an appropriate correction value CL corresponding to the change state of the braking force caused by the driver's operation of the brake pedal 32.

  As a result, it is possible to make it difficult for the driver to distinguish between a change in the vehicle acceleration / deceleration due to his / her braking operation and a change in the vehicle acceleration / deceleration due to the offset correction. It is possible to change the correction amount according to the magnitude of the driver sensitivity sensitive term Ds, which is the index value. For this reason, it is possible to improve the convergence speed of the sensor output value to the true value while suppressing the occurrence of the driver's uncomfortable feeling with respect to the vehicle acceleration / deceleration change caused by the correction.

(Third embodiment)
(Constitution)
In the third embodiment, the operation state detection unit 103 detects an operation state of the shift lever 34 (for example, a shift-up operation state, a shift-down operation state, etc.) based on the vehicle shift position SP from the shift sensor 8. Is different from the first and second embodiments. In addition, the sensor output correction device 1 is an index value of the sensitivity of the driver with respect to a change in the acceleration / deceleration of the vehicle caused by the correction of the sensor output value Ga, which changes in accordance with the preset operation state of the shift lever 34 The difference from the first and second embodiments is that a driver sensitivity sensitive term Ds data table is provided. Further, the driver sensitivity sensitive term calculation unit 104 is different from the first and second embodiments in that the driver sensitivity sensitive term calculation unit 104 acquires the driver sensitivity sensitive term Ds corresponding to the input operation state Ss from the data table.

Hereinafter, the same components as those in the first and second embodiments are denoted by the same reference numerals, description thereof will be omitted as appropriate, and different portions will be described in detail.
As shown in FIG. 12, in the third embodiment, the shift position SP detected by the shift sensor 8 is supplied to the controller 10.
The operation state detection unit 103 of the third embodiment first detects the change state of the shift position SP based on the shift position SP input from the shift sensor 8. Specifically, the operation state detection unit 103 detects whether the shift position of the vehicle has been shifted up or down. When the operation state detection unit 103 detects that the upshift has been performed, the operation state detection unit 103 uses the shift operation state information Ss including information indicating that the upshift operation has been performed (hereinafter simply referred to as “shift operation state Ss”) to the driver. Input to the sensitivity-sensitive term calculation unit 104. On the other hand, when the operation state detection unit 103 detects that the downshift has been performed, the operation state detection unit 103 inputs the shift operation state Ss including information indicating that the downshift operation has been performed to the driver sensitivity sensitive term calculation unit 104.

The driver sensitivity sensitive term calculation unit 104 of the third embodiment is based on the offset estimated value Gos input from the offset estimated value calculation unit 102 and the shift operation state Ss input from the operation state detection unit 103. Ds is calculated.
Here, the driver sensitivity sensitivity term Ds of the third embodiment is a value indicating the magnitude of the sensitivity of the driver with respect to the change in acceleration / deceleration caused by the correction of the sensor output value Ga, which changes according to the shift operation state Ss. This is an index value of sensitivity sensitivity value. In the third embodiment, the driver sensitivity sensitivity value is determined by the acceleration or deceleration direction of the vehicle due to the operation state of the shift lever 34 and the acceleration or deceleration direction of the vehicle due to the correction of the sensor output value Ga. At the same time, the operation state of the shift lever 34 becomes smaller as the operation state increases the rate of change of the acceleration / deceleration of the vehicle.

  For example, when the driver performs an upshift operation, the driver's sensitivity to the vehicle acceleration is relatively small, and when the driver performs a downshift operation, the driver's sensitivity to the vehicle deceleration is relatively small. That is, when the sensor output value Ga is corrected when the driver's acceleration / deceleration sensitivity is small, the change in the vehicle acceleration / deceleration caused by this correction is less likely to be felt by the driver. Therefore, the driver's sensitivity to changes in the vehicle acceleration / deceleration caused by the correction is reduced. On the other hand, when the sensor output value Ga is corrected when the driver's vehicle acceleration / deceleration sensitivity is high, changes in the vehicle acceleration / deceleration caused by this correction are easily felt by the driver. Therefore, the driver's sensitivity to changes in the vehicle acceleration / deceleration caused by the correction increases.

  On the basis of this, in the third embodiment, for example, driver sensitivity sensitivity is obtained from data of sensitivity to acceleration / deceleration change caused by the above-described correction of an unspecified number of drivers with respect to the operation state of the shift lever 34 obtained by experiments. Create a table of terms in advance. The table created in this way is stored in advance in a memory (not shown) provided in the sensor output correction device 1.

  In the third embodiment, based on the shift operation state Ss, the acceleration or deceleration direction of the vehicle caused by the operation state of the shift lever 34 of the driver is the same as the acceleration or deceleration direction of the vehicle caused by the correction. In this case, correction of the sensor output value Ga is permitted. On the other hand, when the direction of acceleration or deceleration of the vehicle due to the operating state of the shift lever 34 of the driver is different from the direction of acceleration or deceleration of the vehicle due to the correction, the correction of the sensor output value Ga is prohibited.

  For example, when the driver performs an upshift operation of the shift lever 34 with the intention of acceleration, the gear of a transmission (not shown) mounted on the vehicle is shifted up and the vehicle is accelerated. At this time, the correction of the sensor output value Ga is permitted when the vehicle is accelerated by the control using the corrected sensor output value Gc. On the other hand, correction of the sensor output value Ga is prohibited when the vehicle decelerates by control using the corrected sensor output value Gc.

  Further, when the driver performs a downshift operation of the shift lever 34 with the intention of decelerating, the gear of a transmission (not shown) mounted on the vehicle is shifted down and the vehicle is decelerated. At this time, correction of the sensor output value Ga is permitted when the vehicle decelerates by control using the corrected sensor output value Gc. On the other hand, when the vehicle is accelerated by control using the corrected sensor output value Gc, the correction of the sensor output value Ga is prohibited.

In the third embodiment, an acceleration-side correction driver sensitivity sensitivity term table that is a table of driver sensitivity sensitivity terms when offset correction is performed on the vehicle acceleration side, and a driver when offset correction is performed on the vehicle deceleration side A driver sensitivity sensitive term table at the time of deceleration side correction, which is a sensitivity sensitive term table, is prepared.
The acceleration-side correction driver sensitivity sensitive term table of the third embodiment has a characteristic that becomes a value (positive value) larger than “0” when shifted up and becomes “0” when shifted down. It is.

Further, the deceleration-side correction driver sensitivity sensitivity term table of the third embodiment has a characteristic that becomes “0” when shifted up and becomes a value (positive value) larger than “0” when shifted down. It is a table.
Then, when the estimated offset value Gos is a negative value, the driver sensitivity sensitive term calculation unit 104 determines to perform offset correction on the vehicle acceleration side.

Here, in the third embodiment, when the offset estimated value Gos is a negative value, the sensor output value Ga is lower than the true value. In addition, it is assumed that the control that causes the vehicle to accelerate due to this correction is performed by performing correction so that the sensor output value Ga in this state approaches a true value.
Accordingly, the driver sensitivity sensitive term calculation unit 104 acquires the driver sensitivity sensitive term Ds corresponding to the shift operation state Ss from the acceleration side driver sensitivity sensitive term table.

On the other hand, when the estimated offset value Gos is a positive value, the driver sensitivity sensitive term calculation unit 104 determines to perform offset correction on the vehicle deceleration side.
Here, in the third embodiment, when the offset estimated value Gos is a positive value, the sensor output value Ga is higher than the true value. In addition, it is assumed that control is performed so that the vehicle is decelerated due to this correction by performing correction so that the sensor output value Ga in this state approaches a true value.
Therefore, the driver sensitivity sensitive term calculation unit 104 acquires the driver sensitivity sensitive term Ds corresponding to the shift operation state Ss from the driver sensitivity sensitive term table at the time of deceleration side correction.
The driver sensitivity sensitive term calculation unit 104 inputs the acquired driver sensitivity sensitive term Ds to the correction permission coefficient calculation unit 106.

(Operation)
Next, the operation of the sensor output correction apparatus 1 according to the third embodiment will be described.
When the ignition switch is turned on, the shift position SP from the shift sensor 8, the sensor output value Ga from the acceleration sensor 2, the wheel speeds Vh1 to Vh4 from the wheel speed sensor 5, and the motor current Im from the motor current sensor 7 are controlled. 10 is supplied. In addition, the steering angle θ from the steering angle sensor 6 is supplied to the controller 10.

  When the shift position SP is input from the shift sensor 8, the operation state detector 103 detects the operation state of the shift lever 34 based on the input shift position SP. As a result, when it is detected that the upshift has been performed, the shift operation state Ss including information indicating that the upshift operation has been performed is input to the driver sensitivity sensitive term calculation unit 104. On the other hand, when it is detected that the downshift has been performed, the shift operation state Ss including information indicating that the downshift operation has been performed is input to the driver sensitivity sensitive term calculation unit 104.

Further, the offset estimated value calculation unit 102 inputs the calculated offset estimated value Gos to the driver sensitivity sensitive term calculation unit 104.
When the driver sensitivity sensitive term calculation unit 104 determines that the input offset estimated value Gos is a negative value, the input shift operation state is determined from the acceleration-side corrected driver sensitivity sensitive term table indicated by T901 in FIG. A driver sensitivity sensitive term Ds corresponding to Ss is acquired. As shown in T901 of FIG. 13, the acceleration-side correction driver sensitivity sensitive term table has a positive value as a value at the time of shift-up and “0” as a value at the time of shift-down. The acceleration-side correction driver sensitivity sensitivity term table has different positive values depending on the contents of the upshift, such as 1st to 2nd, 2nd to 3rd, for example.

On the other hand, if the driver sensitivity sensitive term calculation unit 104 determines that the input offset estimated value Gos is a positive value, the input shift shift is input from the deceleration-side corrected driver sensitivity sensitive term table indicated by T902 in FIG. A driver sensitivity sensitive term Ds corresponding to the operation state Ss is acquired. As shown in T902 of FIG. 13, the deceleration-side correction driver sensitivity sensitivity term table has a positive value as a value at the time of downshifting and “0” as a value at the time of upshifting. The driver sensitivity sensitive term table at the time of deceleration side correction has a positive value that varies depending on the contents of the downshift, such as 3rd to 2nd, 2nd to 1st.
The driver sensitivity sensitive term calculation unit 104 inputs the acquired driver sensitivity sensitive term Ds to the correction permission coefficient calculation unit 106 (step S203).
Subsequent operations are the same as those in the first and second embodiments, and a description thereof will be omitted.

  Here, the acceleration sensor 2 corresponds to an acceleration sensor. The drive torque estimation unit 100 corresponds to the drive torque estimation unit. The acceleration estimated value calculation unit 101 corresponds to the acceleration estimated value calculation unit. The offset estimated value calculation unit 102 corresponds to the offset estimated value calculation unit. The operation state detection unit 103 corresponds to the operation state detection unit. The driver sensitivity sensitive term calculation unit 104 corresponds to a driver sensitivity sensitive value setting unit. The correction reliability calculation unit 105 corresponds to the correction reliability calculation unit. The correction value limiting unit 107 corresponds to the correction value limiting unit. The output value correction unit 108 corresponds to the output value correction unit. The sensitivity of the driver to the change in the acceleration / deceleration of the vehicle due to the correction of the sensor output value Ga, which changes according to the shift operation state Ss, corresponds to the driver sensitivity sensitivity value. The shift lever 34 corresponds to a shift operator.

(Effect of the third embodiment)
In addition to the effects of the first and second embodiments, the present embodiment has the following effects.
(1) The braking / driving force instruction operator includes the shift lever 34. The driver sensitivity sensitivity term Ds, which is an index value of the driver sensitivity sensitivity value, is set to a value that changes according to the operation state (shift operation state Ss) of the shift lever 34 of the driver.
With this configuration, the sensor output value Ga can be corrected with an appropriate correction value CL corresponding to the operation state of the driver's shift lever 34.
As a result, it is possible to make it difficult for the driver to distinguish between a change in the acceleration / deceleration of the vehicle due to his / her shift operation and a change in the acceleration / deceleration of the vehicle due to the offset correction, and the driver sensitivity sensitivity term. The correction amount can be changed according to the magnitude of Ds. For this reason, it is possible to improve the convergence speed of the sensor output value to the true value while suppressing the occurrence of the driver's uncomfortable feeling with respect to the vehicle acceleration / deceleration change caused by the correction.

(Modification)
(1) In the first to third embodiments, the acceleration estimated value Ge is calculated based on the estimated torque Te and the running resistance R. However, the present invention is not limited to this configuration. For example, the acceleration estimated value Ge may be calculated in consideration of turning resistance and friction braking force. Further, the dependent variable and map of the correction reliability Cc may be changed according to these factors.
(2) In the first to third embodiments, the acceleration estimated value Ge is calculated based on the estimated torque Te and the running resistance R. However, the present invention is not limited to this configuration. For example, the acceleration estimated value Ge may be calculated in consideration of the effect that the value of the acceleration sensor itself shifts due to the slip angle of the vehicle or the pitching of the vehicle. Further, the dependent variable and map of the correction reliability Cc may be changed according to these factors.

(3) In the first to third embodiments, the driver sensitivity sensitive term Ds is changed by using any one of the accelerator operation, the brake operation, and the shift operation. It is good also as a structure used combining.
(4) In the first to third embodiments, the driver sensitivity sensitive term Ds is changed using any one of the accelerator operation, the brake operation, and the shift operation. However, the present invention is not limited to this configuration. For example, it is good also as a structure changed according to on / off operation of the air conditioner of a driver.

(5) In the first to third embodiments, the offset estimated value Gos is obtained from the difference between the acceleration estimated value Ge and the sensor output value of the acceleration sensor 2. However, the present invention is not limited to this configuration. For example, as the estimated offset value Gos when the correction reliability Cc is outside a predetermined threshold range, the difference between the acceleration estimation value Gos and the sensor output value Ga when the correction reliability Cc is within the predetermined threshold range is held. You may use what you did.

(6) In the first to third embodiments, the driver sensitivity sensitive term Ds corresponding to the operation state is obtained from the driver sensitivity sensitive term map or the driver sensitivity sensitive term table. However, the present invention is not limited to this configuration. For example, the driver sensitivity sensitive term map or the driver sensitivity sensitive term table may be functionalized, and the driver sensitivity sensitive term Ds may be obtained by calculation using this function. This is because, in the first to third embodiments, the map of the steering angle sensitivity term Dθ, the map of the vehicle speed sensitivity term Dv, the map of the vehicle acceleration sensitivity term Dg, and the offset used when the correction reliability Cc is obtained. The estimated value sensitive term Dos map may be similarly functionalized to obtain each value by calculation.

(7) In the first to third embodiments, the output correction device 1 for a vehicle acceleration sensor according to the present invention is applied to a so-called electric vehicle using a braking / driving motor as a power source. However, the present invention is not limited to this, and the present invention can be applied to an automobile using an internal combustion engine as a power source or a hybrid vehicle including an internal combustion engine and a braking / driving motor.
The above embodiments are preferable specific examples of the present invention, and various technically preferable limitations are given. However, the scope of the present invention is described in particular in the above description to limit the present invention. As long as there is no, it is not restricted to these forms. In the drawings used in the above description, for convenience of illustration, the vertical and horizontal scales of members or parts are schematic views different from actual ones. In addition, the present invention is not limited to the above-described embodiments, and modifications, improvements, equivalents, and the like within the scope that can achieve the object of the present invention are included in the present invention.

DESCRIPTION OF SYMBOLS 1 Output correction device of vehicle acceleration sensor 2 Acceleration sensor 3 Acceleration sensor 4 Brake sensor 5 Wheel speed sensor 6 Steering angle sensor 7 Motor current sensor 8 Shift sensor 10 Controller 12 Brake actuator 20 Travel support device 21 Motor current supply inverter 22 Driving motor 30 Accelerator pedal 32 Brake pedal 34 Shift lever 100 Driving torque estimation unit 101 Acceleration estimation value calculation unit 102 Offset estimation value calculation unit 103 Operation state detection unit 104 Driver sensitivity sensitive term calculation unit 105 Correction reliability calculation unit 106 Correction permission Coefficient calculator 107 Correction value limiter 108 Output value corrector

Claims (11)

An acceleration sensor mounted on the vehicle for detecting the acceleration of the vehicle;
An offset estimated value calculation unit that calculates an offset estimated value that is an estimated value of the offset value of the acceleration sensor;
An output value correction unit that performs correction by adding a correction value to the sensor output value of the acceleration sensor so as to cancel the offset estimation value;
An operation state detection unit for detecting an operation state of a braking / driving force instruction operator for instructing the braking / driving force of the vehicle;
A driver that sets a driver sensitivity sensitivity value indicating the magnitude of the driver's sensitivity to acceleration or deceleration of the vehicle caused by travel control using the corrected sensor output value based on the operation state detected by the operation state detection unit Sensitivity sensitivity setting section,
A correction value limiting unit that limits the size of the correction value using the driver sensitivity sensitive value set by the driver sensitivity sensitive value setting unit, and
The driver sensitivity sensitive value includes a direction of acceleration or deceleration of the vehicle caused by operation of the braking / driving force indicator operator and a direction of acceleration or deceleration of the vehicle caused by travel control using the corrected sensor output value. Is the value that becomes smaller as the operation state is an operation state that increases the rate of change of acceleration / deceleration of the vehicle,
The output correction device for an acceleration sensor for a vehicle, wherein the correction value limiting unit limits the magnitude of the correction value so that the change in the sensor output value becomes smaller as the driver sensitivity sensitivity value becomes larger. A drive torque estimating unit for estimating the drive torque of the vehicle;
An acceleration estimated value calculation unit that calculates an acceleration estimated value that is an estimated value of the acceleration of the vehicle based on the driving torque estimated by the driving torque estimating unit;
The output correction of the vehicular acceleration sensor according to claim 1, wherein the offset estimated value calculation unit calculates the offset estimated value by subtracting a sensor output value of the acceleration sensor from the acceleration estimated value. apparatus.   The correction value limiting unit changes the correction value from a preset initial value toward a value that cancels the offset estimated value, and reduces the rate of change of the correction value as the driver sensitivity sensitivity value increases. The output correction device for a vehicle acceleration sensor according to claim 1 or 2.   The correction value limiting unit includes a direction of acceleration or deceleration of the vehicle caused by operation of the braking / driving force instruction operator, and a direction of acceleration or deceleration of the vehicle caused by travel control using the corrected sensor output value. The vehicle is caused by the travel control using the direction of acceleration or deceleration of the vehicle caused by the operation of the braking / driving force indicating operator and the sensor output value after the correction. The output correction device for an acceleration sensor for a vehicle according to any one of claims 1 to 3, wherein the correction is prohibited when the acceleration or deceleration direction of the vehicle is different. The operation state detection unit is configured to detect an operation speed of the braking / driving force instruction operator.
The output correction device for an acceleration sensor for a vehicle according to any one of claims 1 to 4, wherein the driver sensitivity sensitivity value is set to a value that decreases as the operation speed increases. Based on at least one of the vehicle state of the vehicle, an acceleration estimated value that is an estimated value of the vehicle acceleration, and the offset estimated value, a correction reliability that is a coefficient that depends on the probability of the offset estimated value is calculated. A correction reliability calculation unit is provided,
The output correction device for an acceleration sensor for a vehicle according to any one of claims 1 to 5, wherein the correction value restriction unit reduces the restriction amount of the correction value as the correction reliability increases. The correction reliability calculation unit is configured to calculate the correction reliability based on at least the acceleration estimated value,
The output correction device for an acceleration sensor for a vehicle according to claim 6, wherein the correction reliability is set to a value that increases a limit amount of the correction value as the estimated acceleration value increases. The correction reliability calculation unit is configured to calculate the correction reliability based on at least the offset estimated value,
The output correction device for an acceleration sensor for a vehicle according to claim 6 or 7, wherein the correction reliability is set to a value that decreases a limit amount of the correction value as the estimated offset value increases. The braking / driving force instruction operator includes an accelerator operator,
The output correction of the acceleration sensor for a vehicle according to any one of claims 1 to 8, wherein the driver sensitivity sensitivity value is set to a value that changes in accordance with an operation state of the accelerator operator by a driver. apparatus. The braking / driving force instruction operator includes a brake operator,
10. The vehicle according to claim 1, wherein the driver sensitivity sensitivity value is set to a value that changes in accordance with a change state of a braking force caused by an operation of the brake operator by a driver. Output correction device for acceleration sensor. The braking / driving force instruction operator includes a shift operator operated by a driver to indicate a shift position;
The output correction of the vehicle acceleration sensor according to any one of claims 1 to 10, wherein the driver sensitivity sensitivity value is set to a value that changes in accordance with an operation state of the shift operator by a driver. apparatus.

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