KR20180065834A - Apparatus and method for controlling deceleration on heterogeneous road surface using acceleration sensor - Google Patents

Abstract

The present invention relates to an apparatus and method for controlling deceleration on a heterogeneous road surface using an acceleration sensor, in which braking and steering on wheels on a relatively non-slippery road surface are automatically controlled by the acceleration sensor to secure a deceleration amount, in view of phenomenon of which braking amount is decreased by an ABS, when a vehicle is driving on the heterogeneous road of which any one road surface is slippery. When the driving vehicle is decelerated or braked on the heterogeneous road of which any one road surface is slippery, the braking force is compensated by the acceleration sensor so that the braking amount is not decreased by operation of the ABS, thereby securing the deceleration amount. Therefore, it is possible to reduce a braking distance and decreasing a collision risk against a front obstacle or oncoming or following vehicles.

Description

Apparatus and method for deceleration control on heterogeneous road surface using acceleration sensor. {Apparatus and method for controlling deceleration on heterogeneous road surface using acceleration sensor}

The present invention relates to an apparatus and method for deceleration control on a heterogeneous road surface using an acceleration sensor provided inside a ground plane of each tire. More particularly, the present invention relates to a deceleration control apparatus and method for controlling deceleration on a heterogeneous road surface The braking amount is reduced by the operation of the ABS (Anti-lock Brake System) when the braking is carried out by using the acceleration sensor provided inside the ground surface of each of the tires, And more particularly, to an apparatus and method for deceleration control on a heterogeneous road surface using an acceleration sensor capable of ensuring a deceleration amount by automatically controlling the steering and the steering.

When the vehicle performs braking on a slippery road surface or sudden sudden braking, some of the wheels are locked due to the same weight being not applied to the four wheels, that is, a lock-up phenomenon occurs.

This means that the wheels are completely stopped when the vehicle is still running, but the vehicle slides or sideways, making it impossible for the driver to properly control the direction of the car.

To avoid this problem, you must pump the brake pedal so that the wheel does not lock.

This pumping operation corresponds to the ABS technology in which braking is performed by repeating at least ten times per second using an electronic control device or a mechanical device.

On the other hand, if only one of the four wheels of the running vehicle performs the deceleration or braking on the slippery different-type road surface, the ABS is operated on the road-side wheel with low frictional force, (Low-μ) that reduces the brake pressure is executed in the same way as the road surface with low frictional force, and as a result, the total braking amount is lowered so that the obstacle ahead or the risk of collision with the preceding or following vehicle .

That is, if the braking force of 30 bar is applied to both wheels on the normal road surface and the brake pressure of 60 bar acts on both wheels, the slippery road surface becomes the reference on the different road surface, and the braking force of 15 bar is applied to the braking force on the normal road surface as a whole Resulting in a brake pressure of 30 bar, which is half of that.

Therefore, if the braking is performed under the above-described conditions, there is a risk that an accident that collides with a preceding obstacle, a preceding vehicle, or a following vehicle may occur.

JP 1998-351175

SUMMARY OF THE INVENTION The present invention is conceived in view of the above circumstances, and it is an object of the present invention to provide a braking system capable of reducing a braking amount by the operation of an ABS (Anti-lock Brake System) when decelerating or braking on only one of the wheels of a running vehicle on a slippery different- A method of ABS deceleration control on a heterogeneous road surface in which a deceleration amount can be ensured by automatically controlling braking and steering on wheels on a normal road surface using an acceleration sensor provided inside the ground plane of each of the tires, The system has a purpose to provide.

According to an embodiment of the present invention, there is provided a deceleration control apparatus for an automobile, which includes an acceleration sensor mounted inside a tire provided in a vehicle, An ABS (Anti-lock Brake System) for preventing the occurrence of a lock-up phenomenon in which the wheels are locked through the control of the bidirectional braking device, an electronic power steering device for controlling the steering of the wheels in accordance with a predetermined control signal, And a control unit for controlling the electronic power steering apparatus to generate an inverse moment by increasing a torque in a direction opposite to a direction in which the vehicle is expected to turn, wherein the control unit controls the deceleration The braking amount and the turning moment are calculated, and based on the calculation result, an acceleration for controlling the ABS and the electronic power steering device It is possible for the deceleration control apparatus using the road surface sensor in a heterogeneous provided.

The acceleration sensor is disposed in the ground plane of each of the four tires provided in the vehicle. The acceleration sensor is disposed on the center line bisecting the width of the tire and is disposed in the x and y axis directions parallel to the ground surface and in the z axis direction It is desirable to measure the acceleration of the component.

The control unit senses a heterogeneous road surface based on information applied from the acceleration sensor, and when the braking is performed on the different road surface, the braking force reduction amount for the slip road surface side wheel caused by the operation of the ABS It is possible to generate the reverse moment by controlling the electronic power steering device in addition to increasing the braking force on the road surface of the road surface relatively slippery correspondingly and by controlling the brake pedal operation signal of the driver and the output value of the acceleration sensor And the inter-vehicle distance information between the preceding vehicle and the preceding vehicle outputted from the inter-vehicle distance controller, to calculate the deceleration braking amount and the turning moment.

In addition, the control unit may be implemented in an ECU (Electronic Control Unit).

According to another aspect of the present invention, there is provided a method of controlling deceleration in a vehicle to which an anti-lock brake system (ABS) is applied, A brake signal discrimination step for discriminating whether or not the brake is actuated by the driver during driving, a road surface state judging step for judging whether or not the road surface is a heterogeneous road surface while the vehicle is traveling, a distance from the preceding vehicle The braking force increase amount for the wheel on the normal road surface is calculated in accordance with the braking force reduction amount for the slippery road surface side wheel by the operation of the ABS, and the vehicle turning moment is compensated for A compensating braking force calculating step of calculating an inverse moment for calculating a compensating braking force based on a result calculated in the compensating braking force calculating step Wherein the compensating braking force calculating step calculates the compensating braking force based on the inter-vehicle distance information measured in the inter-vehicle distance sensing step, the brake pedal operation signal of the driver, and the output value of the acceleration sensor, It is possible to provide a deceleration control method on a heterogeneous road surface using an acceleration sensor, characterized in that the same amount and turning moment are calculated.

The step of determining the road surface state may include an acceleration variation amount detection step of detecting an acceleration variation amount using an acceleration sensor provided on a center line bisecting the width of the tire provided inside the ground plane of each of the four tires provided in the vehicle, And a road surface difference discrimination step of discriminating whether or not the road surface is a different kind of road surface with the detected acceleration variation amount through the acceleration variation amount detection step.

The wheel braking step may include a wheel brake pressure control step of increasing a braking force on a relatively slippery road surface in accordance with the braking force reduction amount of the slip road surface side wheel caused by the operation of the braking device including the ABS, It is possible to include a steering control step for compensating for the vehicle turning moment generated by the brake pressure control step.

In addition, during ABS operation, the pressure of the wheel brake 1 (brake pressure) is maintained at a value equal to or lower than the pressure of the master cylinder 2, and the moment the wheel locks or the wheel slip occurs, 3 and the inlet valve 5 are opened, if the wheel locking or the wheel slip is continued, the outlet valve 4 is opened and the return pump 5 is operated so that the wheel brake pressure It is possible to further include performing the decompression.

In this case, it is preferable that the steering control step controls the steering to the slippery road surface side so that the axis value is returned, and a notification step of notifying the driver and the surrounding driver of the situation through the warning lamp and emergency light displayed on the notification device including the center fascia It is possible to include more.

According to the present invention provided by the above-described apparatus configuration and method, when an acceleration sensor is used to perform deceleration or braking on only one of the wheels of a running vehicle on a slippery hybrid road surface, an ABS (Anti-lock Brake System) The braking amount can be secured by compensating the corresponding braking force so that the braking amount is not reduced by the operation of the braking force reducing means, thereby reducing the braking distance and reducing the risk of collision with the preceding obstacle, the preceding vehicle or the following vehicle .

1 is a flowchart of a deceleration control method on a heterogeneous road surface using an acceleration sensor according to an embodiment of the present invention.
2 is a flowchart of a deceleration control method on a heterogeneous road surface using an acceleration sensor according to an embodiment of the present invention.
3 is a schematic diagram of a tire grounding length change and an acceleration change with respect to a traveling direction of a vehicle showing an embodiment of the present invention.
4 is a schematic diagram of a hydraulic modulator illustrating an embodiment of the present invention.
5 is a cross-sectional view showing a configuration in which an acceleration sensor according to an embodiment of the present invention is provided.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. It is to be understood that the terms "comprises", "having", and the like in the specification are intended to specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, or combinations thereof.

Also, the terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

In addition, the terms " part, "" unit," " module, "and the like, which are described in the specification, refer to a unit for processing at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software .

In the following description with reference to the accompanying drawings, the same reference numerals are given to the same constituent elements, and a duplicate description thereof will be omitted. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Hereinafter, terms used in describing the present invention will be simply defined as follows.

1 is a flowchart of a deceleration control method on a heterogeneous road surface using an acceleration sensor according to an embodiment of the present invention.

Referring to FIG. 1, it is possible to confirm a flowchart of a deceleration control method on a heterogeneous road surface using an acceleration sensor, which is divided into an input unit, a control unit, and an operation unit.

Specifically, a tire sensor (acceleration sensor) signal and a brake pedal operation signal are transmitted to an ECU (electronic control unit) or a BCM (body control module) provided in the control unit, and the ECU receives and stores the signals, It is possible to process and transmit the signal to a control device (alarm device including braking, emergency, and notification device).

In this case, the MDPS (Motor Driven Power Steering) preferably controls the steering.

In this case, referring to FIG. 5, the acceleration sensor is an acceleration sensor that is provided inside the tire and measures a plurality of elements, which is different from a sensor that measures a conventional simple tire pressure.

More specifically, a variable including the acceleration is provided at one point on the center line bisecting the width of the tire, and the wireless acceleration data value is transmitted to the microcontroller or the like.

It is preferable that the acceleration sensor measures the acceleration in the x and y axis directions parallel to the ground and the z axis component perpendicular to the ground surface. It is possible to provide a sensor provided on one inner surface of the ground plane of each of the tires so that analysis can be performed.

There is a characteristic that control and a method of a deceleration control device on a heterogeneous road surface using the acceleration sensor can be performed through a series of procedures described above.

2 is a flowchart of a deceleration control method on a heterogeneous road surface using an acceleration sensor according to an embodiment of the present invention.

Specifically, in a vehicle deceleration control apparatus, an acceleration sensor mounted inside a tire provided in a vehicle, and a lock-up (lock-up) system in which the wheel is locked through the control of the braking device during braking of the vehicle an ABS (Anti-lock Brake System) that prevents the occurrence of a lock-up phenomenon, an electronic power steering device that controls the steering of the wheel in accordance with a predetermined control signal, an inter-vehicle distance control device that controls the distance to the preceding vehicle during traveling, And a control unit for controlling the electronic power steering apparatus to generate an inverse moment by increasing a torque in a direction opposite to a direction in which the vehicle is expected to turn, wherein the control unit calculates a deceleration braking amount and a turning moment, There is provided a deceleration control device on a heterogeneous road surface using an acceleration sensor for controlling the ABS and the electronic power steering device .

In this case, the acceleration sensor is provided on an inner surface of each of the four tires provided in the vehicle, and is provided on the center line bisecting the width of the tire, and is disposed in the x and y axis directions (longitudinal and transverse directions ) And the acceleration of the z-axis component perpendicular to the ground.

In addition, the control unit senses a heterogeneous road surface based on information applied from the acceleration sensor and determines whether the vehicle is in danger. When braking on the heterogeneous road surface, a slippery road surface side It is possible to increase the braking force for the wheel on the road surface relatively slippery according to the braking force reduction amount for the wheel at a predetermined ratio and to control the electronic power steering device MDPS to generate an inverse moment, A pedal operation signal, an output value of the acceleration sensor, and an inter-vehicle distance information between the preceding vehicle and the preceding vehicle outputted from the inter-vehicle distance control device, calculates a deceleration braking amount and a turning moment, blinks the emergency light, It is possible to provide.

The control unit may be implemented in an ECU (Electronic Control Unit).

Specifically, when the vehicle performs braking on a slippery road surface or sudden sudden braking, the same braking force is not applied to the four wheels, and some of the wheels are locked, that is, a lock-up phenomenon occurs.

This means that the wheels are completely stopped when the vehicle is still running, but the vehicle slides or sideways so that the driver can not control the direction of the car.

To avoid this problem, you must pumping the brakes so that the wheels do not lock.

This pumping operation was repeated 10 times per second using an electronic control device or a mechanical device so that braking was performed.

On the other hand, when only one of the four wheels of the running vehicle performs the deceleration or braking on the slippery different road surface, the ABS is operated on the road surface wheel with low frictional force, In this high road surface side wheel, a pumping operation (Low-mu) for lowering the brake pressure is executed in the same way as the road surface with low frictional force, and as a result, the braking amount is lowered so that the obstacle ahead or the preceding or following vehicle The risk of doing so increases.

In other words, if a braking force of 30 bar is applied to both wheels on a normal road surface and a brake pressure of 60 bar is applied to both wheels, a slippery road surface is a reference on a different road surface, and a braking force of 15 bar is applied to the road surface on a relatively non- The braking force of 30bar, which is half of the braking force, is applied.

Therefore, if the braking is performed under the above-described conditions, there is a risk that an accident that collides with a preceding obstacle, a preceding vehicle, or a following vehicle may occur.

The Intelligent Tire System used here is a next-generation high value-added system that monitors the condition of a tire by mounting a chip or an acceleration sensor inside the tire and transmits the tire condition to the driver in real time to ensure the safety of the vehicle.

This intelligent tire monitoring system communicates with various safety devices for the safety of the driver and passengers and provides tire monitoring data with various safety devices.

The x, y, and z-axis acceleration sensors in each tire for each wheel detect an acceleration change amount. When the vehicle approaches the different road surface, the direction of the vehicle in the intelligent tire system, The acceleration variation of the tire and the wheel with respect to the longitudinal direction balanced with each other is detected and compared with each wheel of the vehicle.

3 is a schematic diagram of a tire grounding length change and an acceleration change with respect to a traveling direction of a vehicle showing an embodiment of the present invention.

In this case, referring to FIG. 3, there is a difference in the grounding angles (theta) corresponding to the tires because the road surface state grounded to the left and right wheels of the vehicle is different and the longitudinal acceleration variations in the direction parallel to the road surface are different Can be confirmed.

The acceleration A = (a_FL, a_FR, a_RL, a_RR), and the left / right wheel surface state comparison is as follows: || a_FL + a_RL || / || a_FR + a_RR || > = alpha0, || a_FL / a_FR || > = alpha1, || a_RL / a_RR || > = alpha2.

Also, the X-axis direction grounding time Tx = (Tx_FL, Tx_FR, Tx_RL, Tx_RR), and the left / right wheel road surface state comparison is || Tx_FL + Tx_RL || / || Tx_FR + Tx_RR || > = beta0, || Tx_FL / Tx_FR || > = beta1, || Tx_RL / Tx_RR || > = beta2.

Further, the X-axis direction ground angle Angle_x = (Angle_x_FL, Angle_x_FR, Angle_x_RL, Angle_x_RR), and the left / right wheel surface state comparison is || Angle_x_FL + Angle_x_RL || / || Angle_x_FR + Angle_x_RR || > = gamma0, || Angle_x_FL / Angle_x_FR || > = gamma1, || Angle_x_RL / Angle_x_RR || > = gamma 2 is possible.

To summarize, if alpha0 ~ 2, beta0 ~ 2, gamma0 ~ 2 = 1, left / right road surface condition is the same.

If Alpha0 ~ 2, Beta0 ~ 2, gamma0 ~ 2> 1, the left road surface is slippery than the right road surface.

If Alpha0 ~ 2, Beta0 ~ 2, gamma0 ~ 2 < 1, the right road surface corresponds to a slippery road surface than the left road surface.

In this case, when the value is larger or smaller than a predetermined value of Alpha 0 to 2, Beta 0 to 2, and gamma 0 to 2, control is performed to detect the left and right road surface difference to ensure the running and braking stability of the vehicle .

To this end, the present invention provides a method for controlling deceleration in a vehicle to which an anti-lock brake system (ABS) is applied, comprising the steps of: detecting a driving state of the vehicle; A brake signal discrimination step of discriminating whether or not the brake is operated by the driver, a road surface condition judging step of judging whether or not the road surface is a heterogeneous road surface of the vehicle while the vehicle is traveling, Calculating a braking force increase amount for the wheel on the normal road surface in accordance with the braking force reduction amount for the slip road surface side wheel caused by the operation of the ABS when braking on the different road surface, Based on a result calculated in the compensating braking force calculating step and a braking-force calculating step of calculating a braking- Wherein the compensating braking force calculating step calculates a compensating braking force based on the deceleration braking amount and the turning moment using the inter-vehicle distance information measured in the inter-vehicle distance sensing step, the brake pedal operation signal of the driver, and the output value of the acceleration sensor It is possible to provide a deceleration control method on a heterogeneous road surface using an acceleration sensor.

Specifically, the road surface state determining step may include an acceleration variation detecting step of detecting an acceleration variation using an acceleration sensor provided on a center line dividing the width of the tire, the acceleration variation detecting step being provided on an inner surface of each of four tires provided in the vehicle, And a road surface difference discriminating step of discriminating whether or not the road surface is a different kind of road surface with the detected acceleration variation amount through the acceleration variation detecting step.

In this case, the process of detecting an acceleration variation using the acceleration sensor and the process of determining whether or not the vehicle is a different kind of road with the detected acceleration variation amount can detect the acceleration variation using the above-described method.

The wheel braking step may include a wheel brake pressure control step of increasing a braking force on a relatively slippery road surface in accordance with the braking force reduction amount of the slip road surface side wheel caused by the operation of the braking device including the ABS, It is possible to include a steering control step for compensating for the vehicle turning moment generated by the brake pressure control step.

4 is a schematic diagram of a hydraulic modulator illustrating an embodiment of the present invention.

More specifically, when the ABS is operated, the pressure of the wheel brake 1 (brake pressure) is maintained at a value equal to or lower than the pressure of the master cylinder 2, and a wheel locking phenomenon or a wheel slip occurs The inlet valve 3 is opened but the locking of the wheel or the slip of the wheel is continued so that the outlet valve 4 is opened and the return pump 5 is operated Thereby performing the wheel brake pressure control step by performing depressurization of the wheel brake pressure.

It is possible to provide the brake pedal 7 and the brake booster 6 configuration for instantly maximizing the brake braking and it is possible to provide a configuration including the damping chamber 8 and the brake fluid accumulating device 9 .

In addition, it is preferable that the steering control for compensating the vehicle turning moment generated by the wheel brake pressure control step controls the steering to the slippery road surface side at a predetermined angle so that the shaft value is turned on.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention.

Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

1: Brake
2: Master cylinder
3: Inflow valve
4: Outflow valve
5: Return pump
6: Brake booster
7: Brake pedal
8: Damping chamber
9: Brake fluid accumulator

Claims (11)

A deceleration control apparatus for an automobile,
An acceleration sensor mounted on an inner side of a tire provided in a vehicle;
An ABS (Anti-lock Brake System) for preventing a lock-up phenomenon in which a wheel is locked through control of a braking device when braking the vehicle based on a detection signal of the acceleration sensor;
An electronic power steering device for controlling the steering of the wheel in accordance with a predetermined control signal;
An inter-vehicle distance control device for controlling the distance to the preceding vehicle during driving; And
A control unit for controlling the electronic power steering apparatus to generate an inverse moment by increasing a steering torque in a direction opposite to a direction in which the vehicle is expected to turn;
, &Lt; / RTI &
Wherein the control unit calculates an amount of deceleration braking and a turning moment, and controls the ABS and the electronic power steering apparatus based on the calculation result.
The method according to claim 1,
The acceleration sensor includes:
The acceleration is measured in the x-axis direction and the z-axis direction component perpendicular to the ground, which are provided on the inner surface of each of the four tires provided in the vehicle and are provided on the center line bisecting the width of the tire and parallel to the ground. Wherein the deceleration control unit is configured to control the deceleration of the vehicle.
The method according to claim 1,
Wherein,
Wherein the control unit senses a heterogeneous road surface based on information applied from the acceleration sensor, and when the braking is performed on the different road surface, the braking force is relatively slippery corresponding to the braking- Wherein the braking force for a wheel on a road surface is increased at a predetermined ratio and the electronic power steering device is controlled to generate an inverse moment.
The method according to claim 1,
Wherein,
And calculates a deceleration braking amount and a turning moment using the brake pedal operation signal of the driver, the output value of the acceleration sensor, and the inter-vehicle distance information from the preceding vehicle outputted from the inter-vehicle distance control device. Deceleration control device on road surface.
The method according to claim 1,
Wherein,
Wherein the acceleration sensor is implemented in an ECU (Electronic Control Unit).
A method of controlling deceleration in a vehicle to which an anti-lock brake system (ABS) is applied,
A traveling state detecting step of detecting whether the vehicle is driven;
A brake signal discrimination step of discriminating whether a brake is actuated by a driver during driving of the vehicle;
A road surface state judging step of judging whether a road surface on which the vehicle is traveling is a heterogeneous road surface;
An inter-vehicle distance sensing step of measuring a distance to the preceding vehicle while driving the vehicle;
When braking on a different road surface, the braking force increase amount for the wheel on the steady road surface is calculated in accordance with the braking force reduction amount for the slip road surface side wheel caused by the operation of the ABS, and the reverse moment for compensating the vehicle turning moment is calculated A compensating braking force calculating step And
And a wheel braking step of steering and braking the wheel based on the result calculated in the compensating braking force calculating step,
Wherein the compensating braking force calculating step calculates the decelerating braking amount and the turning moment using the inter-vehicle distance information measured in the inter-vehicle distance sensing step, the driver's brake pedal operation signal, and the output value of the acceleration sensor. Deceleration control method on heterogeneous road surface.
The method according to claim 6,
The road surface condition determination step may include:
An acceleration change amount detecting step of detecting an acceleration change amount using an acceleration sensor provided on an inner surface of each of four tires provided on a vehicle, the acceleration sensor being provided on a center line bisecting the width of the tire; And
A road surface difference discrimination step of discriminating whether or not a different kind of road surface is present with the detected acceleration variation amount through the acceleration variation amount detecting step;
Wherein the deceleration control is performed by using the acceleration sensor.
The method according to claim 6,
The wheel braking step includes:
A wheel brake pressure control step of increasing a braking force on a relatively slippery road surface in accordance with a braking force reduction amount for a slippery road surface side wheel by operation of a braking device including ABS; And
A steering control step of compensating a vehicle turning moment generated by the wheel brake pressure control step;
Wherein the deceleration control is performed by using the acceleration sensor.
9. The method of claim 8,
During ABS operation, the pressure of the wheel brake 1 (brake pressure) is maintained at a value equal to or lower than the pressure of the master cylinder 2, and when the wheel locking or wheel slip occurs, the inlet valves 3, Inlet Valve is opened but when the wheel locking or slip is continued, the Outlet Valve 4 is opened and the return pump 5 is operated to depressurize the wheel brake pressure. Wherein the deceleration control is performed by using an acceleration sensor.
9. The method of claim 8,
Wherein the steering control step includes:
And the steering is controlled to the slippery road surface side so that the shaft value is turned on.
The method according to claim 6,
A notification step of notifying the driver and the surrounding driver of the situation through a warning lamp and an emergency light displayed on the notification device including the center fascia;
Further comprising the steps of: determining a deceleration rate on the different road surface using the acceleration sensor.

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