KR20120106211A - Sensor sensitive steer device electric vehicle and steer control method thereof - Google Patents

Abstract

The electric vehicle of the present invention uses the steering information of the vehicle V detected by the steering angle sensor 61, the accelerator pedal sensor 62, and the brake pedal sensor 63, and the driving ECU 30 drives the left and right front wheels. 1) to control the swing stability, or the braking ECU 40 controls the front / rear wheel braking devices 10 and 20 to maintain the turning stability, thereby driving the driving ECU 30 and the braking ECU 40. Fail-Safe is implemented with the concept of Backup (BackUp), and the cost is reduced by steering that is implemented without the actuators and steering mechanisms required in the steering system such as MDPS or HPS or EHPS. It is possible to easily implement steering functions such as U-turns on narrow roads by widening the steering angle range by restricting the steering mechanism.

Description

Electric vehicle with sensor sensitive steering device and steering control method using the same {Sensor sensitive Steer Device Electric Vehicle and Steer Control Method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vehicle, and more particularly, to an electric vehicle that implements steering without various steering mechanisms connected to a steering wheel and a wheel and a method of controlling an electric vehicle using a sensor-sensitive steering device.

In general, the steering device is a device that can directly respond to the driver's steering intention to control the vehicle in the desired steering direction by bending the wheel in the steering direction with hydraulic pressure or motor power.

6 shows a block diagram of a general steering device applied to a vehicle.

As shown in the figure, the steering wheel 100 which is operated by the driver, the steering ECU 300 which determines the degree of steering intention of the driver from the steering angle sensor 200 which detects the rotation angle of the steering wheel 100, and the wheels It is mechanically connected to the electric steering mechanism 400 for changing the direction of the vehicle in the desired direction by bending the wheel in the steering direction of the steering handle 100 through the control of the steering ECU (300).

The electric steering mechanism 400 is made of MDPS or EPS, HPS or EHPS.

However, such a conventional steering device can not only be limited to the steering angle that the steering range of the vehicle can be implemented in the steering wheel, but in particular, the configuration is complicated by the configuration of the steering mechanism that connects the steering wheel and the wheel. .

In addition, the steering mechanism mounted toward the front wheel should avoid the mutual interference between the steering mechanism components for the steering range during steering, and this restriction on interference avoidance can only reduce the design freedom of the steering apparatus.

Accordingly, the present invention in view of the above point by controlling the steering wheel operation of the driver and the stepped signals of the accelerator pedal and the brake pedal by controlling the driving device of the left and right front wheel and the wheel braking device of the front wheel / rear wheel, It is an object of the present invention to provide an electric vehicle equipped with a sensory steering device capable of realizing steering of a vehicle even without mechanically connecting the wheel and a wheel, and a steering control method using the same.

Electric vehicle equipped with a sensor-sensitive steering device of the present invention for achieving the above object is a drive device consisting of at least one power source to drive the vehicle driving the wheel and controlled by a drive ECU, and is installed on the wheel and braking In the electric vehicle comprising a braking device that restrains the wheel to brake the vehicle and is controlled by a braking ECU,

A steering wheel which the driver turns to and does not have a mechanical connection leading to the wheel to change the vehicle in the desired steering direction,

A steering angle sensor for detecting a rotation angle of the steering wheel handled by an internal algorithm of the driving ECU and the braking ECU, and transmitting the steering angle to the driving ECU and the braking ECU, respectively;

An acceleration pedal sensor which detects the depression stroke of the accelerator pedal of the vehicle processed by the internal algorithm of the driving ECU and the braking ECU and transmits it to the driving ECU and the braking ECU, respectively;

A brake pedal sensor that detects the depression stroke of the brake pedal of the vehicle processed by the internal algorithm of the driving ECU and the braking ECU and transmits it to the driving ECU and the braking ECU, respectively.

Characterized in that configured to include.

The driving ECU and the braking ECU implement cooperative control through communication with each other so as to share information with each other, and have a fail-safe function in which a normal other takes over in case of a failure. Will be implemented.

Communication between the driving ECU and the braking ECU is performed through a network such as CAN communication, MOST communication, or IDB1394 communication.

The driving device includes a left front wheel motor for driving the left wheel of the front wheel and a right front wheel motor for driving the right wheel of the front wheel, and the left front wheel motor and the right front wheel motor are independently controlled by the driving ECU. .

The braking device is an EMB (Electro Mechanical Brake) type installed on the left and right front wheels and the left and right wheels, respectively, and is independently controlled by the braking ECU.

In addition, the steering control method of the electric vehicle using the sensor-sensitive steering device of the present invention for achieving the above object is the driving ECU and the braking ECU received the rotation information of the steering wheel for turning of the vehicle, the depression pedal of the accelerator pedal A turning steering judging step of recognizing information on the depression stroke of the brake pedal;

After receiving the rotation information of the steering wheel and the information about the depression stroke of the accelerator pedal and the brake pedal, the driving ECU and the brake ECU determine the vehicle speed at the time of steering using an internal algorithm, and the wheel inside the turning and turning according to the turning A turning control judging step of calculating and calculating a speed difference generated between the outer wheels;

A turning control step of calculating a required wheel speed for turning stability on the basis of a speed difference calculated between the wheel inside the turning wheel and the wheel outside the turning, and comparing the request wheel speed with the current wheel speed of the turning vehicle;

According to the difference between the required wheel speed and the current wheel speed, the driving ECU controls the left front wheel motor and the right front wheel motor to change the rotational speeds of the wheel inside the turning wheel and the wheel outside the turning wheel, or the braking ECU turns the front wheel. A turning control completion step of changing the rotational speeds of the wheels inside the swing and the wheels outside the swing by controlling braking devices installed on the left rear wheel and the left and right wheels;

It characterized in that it is implemented to include.

The turning control performing step performs the turning control completion step on the basis of the determination that the requested wheel speed is larger than the current wheel speed.

If the required wheel speed is greater than the current wheel speed, the driving ECU controls the left front wheel motor and the right front wheel motor to change the rotational speed of the wheel outside the turning faster than the wheel inside the turning.

If the required wheel speed is not greater than the current wheel speed, it is determined whether the required wheel speed and the current wheel speed are the same before performing the turning control completion step, and according to the determination, whether the turning control completion step is performed or not. To decide.

If the required wheel speed and the current wheel speed are the same, the turning control is completed without performing the turning control completion step, whereas if the requested wheel speed and the current wheel speed are not the same, the braking ECU is installed on the front wheel rear wheel and the rear wheel left and right wheels. Each device is controlled to change the rotational speed of the wheel inside the swing and the wheel outside the swing.

The present invention has a very simple configuration of the steering device is composed of a sensor associated with the ECU for controlling the drive device of the left and right front wheels and the wheel braking device of the front and rear wheels, respectively, in particular steering such as MDPS or HPS or EHPS In the device, the cost can be reduced by eliminating the actuator device and the steering mechanism device related to steering.

In addition, the present invention does not have a steering mechanism device that connects between the steering wheel and the wheel can be widened the range of steering angle during steering, in particular can also easily implement a steering function, such as a U-turn on a narrow road. .

1 is a block diagram of an electric vehicle to which the sensor-sensitive steering device according to the present invention is applied, and FIGS. 2 and 3 are block diagrams of the sensor-sensitive steering device according to the present invention, and FIG. 4 is a sensor-sensitive steering device according to the present invention. FIG. 5 is a steering control diagram of an electric vehicle using a device, and FIG. 5 is a steering control which calculates a speed difference generated between a wheel W inside a swing and a wheel W outside the swing according to the present embodiment when the vehicle moves. 6 is a block diagram of a conventional steering apparatus.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Since the exemplary embodiments of the present invention may be embodied in various different forms, one of ordinary skill in the art to which the present invention pertains may be described herein. It is not limited to the Example to make.

1 is a block diagram of an electric vehicle to which the sensor-sensitive steering apparatus according to the present embodiment is applied.

As shown, the electric vehicle is a drive device (1) consisting of at least one power source for driving the wheel (V) to drive the vehicle (W), and installed on each wheel (W) to brake the wheel (W) when braking A braking device that restrains and brakes the vehicle V, a steering wheel 50 that the driver rotates and does not have a mechanical connection leading to the wheel W to change the vehicle V to the desired steering direction, and the vehicle V A pedal operated by a driver for acceleration and stop of the drive, a drive ECU 30 for controlling the drive device 1, a brake ECU 40 for controlling the brake device, a drive ECU 30, It is composed of a sensor unit 60 for providing a detection signal according to the steering of the vehicle (V) to the braking ECU (40).

The drive device 1 comprises a left front wheel motor 2 for driving a left wheel and a right front wheel motor 3 for driving a right wheel, and the left front wheel motor 2 and the right front wheel motor 3 Each is controlled independently.

The braking device includes a front wheel braking device 10 installed on the left and right front wheels and a rear wheel braking device 20 mounted on the left and right rear wheels to brake the left and right rear wheels, respectively. The brake devices 10 and 20 are applied with EMBs 11, 12, 21, 22, and Electro Mechanical Brake.

In the present embodiment, the EMBs 11, 12, 21, and 22 have been described in the case where they are installed in both the left and right front wheels and the left and right rear wheels.

Typically, EMB (Electro Mechanical Brake) is a type of Brake By Wire System (BBW), a brake-by-wire system that brakes a vehicle without using hydraulic pressure. It is a method using the actuator power.

The driving ECU 30 controls the left front wheel motor 2 and the right front wheel motor 3 independently, and the braking ECU 40 is the front wheel braking device 10 and the EMBs 11 and 12, respectively. The device 20 controls the EMBs 21 and 22, respectively.

In this embodiment, the driving ECU 30 and the braking ECU 40 respectively recognize the information detected by the sensor unit 60 and communicate with each other when controlling the vehicle V according to the determination of the information. Implement cooperative control.

In the cooperative control of the driving ECU 30 and the braking ECU 40 as described above, when one of the driving ECU 30 or the braking ECU 40 fails, the other side replaces the function to fail-safe. -Safe) function can be enhanced.

Communication between the driving ECU 30 and the braking ECU 40 is performed through a network such as CAN communication, MOST communication, or IDB1394 communication.

The sensor unit 60 detects a steering angle of the steering wheel 50 and transmits the steering angle sensor 61 to the driving ECU 30 and the braking ECU 40, respectively, and a stroke according to the stepping of the accelerator pedal. The accelerator pedal sensor 62 transmits to the driving ECU 30 and the braking ECU 40, respectively, and the brake pedal detects a stroke according to the stepping of the brake pedal and transmits the stroke to the driving ECU 30 and the braking ECU 40, respectively. The sensor 63 is comprised.

Communication between the sensors 61, 62, 63 and the driving ECU 30 is indicated by a solid line in FIG. 1, and communication between the sensors 61, 62, 63 and the braking ECU 40 is indicated by a broken line in FIG. do.

2 shows a block diagram in which the vehicle V is driven or braked using the information of the sensor unit 60 according to the present embodiment.

As shown, the information detected by the steering angle sensor 61, the accelerator pedal sensor 62 and the brake pedal sensor 63 is transmitted to the driving ECU 30 and the braking ECU 40, respectively, and determined through an internal algorithm. The speed change or stop of the left / right front wheel motors 2 and 3 is made according to the determination of the driving ECU 30 and the EMBs 11, 12, 21 and 22 are determined according to the determination of the braking ECU 40. The operation of is determined.

In the above determination process, the driving ECU 30 and the braking ECU 40 are implemented with cooperative control with each other through a network such as CAN communication, MOST communication, or IDB1394 communication.

3 shows a cooperative control block diagram implemented in the driving ECU 30 and the braking ECU 40 according to the present embodiment.

As shown in the drawing, the information of the steering angle sensor 61 which detects the steering angle change according to the steering wheel 50 operation of the driver is input to the driving ECU 30 and the braking ECU 40, respectively, and the driver's acceleration The information of the accelerator pedal sensor 62 and the brake pedal sensor 63 which detected the operation of the pedal or brake pedal, respectively, is also input to the driving ECU 30 and the braking ECU 40, respectively.

As described above, the driving ECU 30 and the braking ECU 40 which have received the information of the sensors 61, 62, and 63 determine the control of the vehicle V according to each internal algorithm, and recognize the control of the vehicle V, and then determine According to the result, the driving ECU 30 changes or stops the left / right front wheel motors 2 and 3 and the braking ECU 40 controls the operation of the EMBs 11, 12, 21 and 22. do.

As described above, in the present embodiment, the driving ECU 30 and the braking ECU 40 use the detection information of the sensors 61, 62, and 63, so that in the MDPS, HPS, or EHPS, the actuator device and the mechanical device related to steering can be deleted. Will be.

4 shows a turning steering of the electric vehicle using the sensor-sensitive steering apparatus according to the present embodiment.

As shown in the drawing, when the vehicle V rotates leftward (V-> V ') by the counterclockwise rotation of the steering wheel 50, the left wheel W inside the turning and the right wheel W outside the turning ) Will have a speed difference with respect to the rotation center (Oc) of the vehicle (V).

This is because the rotation radius of the right wheel W located outside the swing is larger than the rotation radius of the left wheel W located at the same rotation center Oc but the inside of the vehicle V. This is due to the occurrence of a speed difference due to the difference in movement distance compared to the same movement time of the left wheel W and the right wheel W.

Therefore, at the time of the turning movement (V-> V ') of the vehicle V, the speed of the turning inner wheel W and the turning outer wheel W are different from each other in consideration of the radius difference with respect to the center of rotation Oc. It is necessary to do this, and through this, even when there is no mechanical connection between the steering wheel 50 and the left and right wheels W, the vehicle V can perform a normal turning movement.

FIG. 5 calculates a speed difference generated between the wheel W inside the swing and the wheel W outside the swing according to the present embodiment during the swing movement (V-> V ′) of the vehicle V as described above. This indicates the order in which steering is controlled.

As shown, in step S10, the rotation of the steering wheel 50 for turning the vehicle V is detected by the steering angle sensor 61 and input to the driving ECU 30 and the braking ECU 40, respectively.

Then, as in step S20, the detection signal of the accelerator pedal sensor 62 or the detection signal of the brake pedal signal 63 is also input to the driving ECU 30 and the braking ECU 40, respectively.

In the present exemplary embodiment, the driving ECU 30 and the braking ECU 40 receiving the detection signal of the accelerator pedal sensor 62 or the brake pedal signal 63 may press the accelerator pedal according to the driving habit of the driver when turning. It is because it can be stepped on the brake pedal.

As described above, when both the steering angle sensor 61 and the accelerator pedal sensor 62 or the detection signals of the brake pedal signal 63 are input to the driving ECU 30 and the braking ECU 40, the driving ECU as in step S30. The 30 and the braking ECU 40 determine the turning direction of the vehicle V using the information of the steering angle sensor 61, and determine the turning direction of the vehicle V using the information of the accelerator pedal sensor 62 or the braking pedal signal 63. Determine the turn speed.

In this case, the turning direction of the vehicle V and the turning speed of the vehicle V calculated as described above are independently performed by the driving ECU 30 and the braking ECU 40, or the driving ECU 30 and the braking ECU ( Only one of 40 may be performed, which means that the driving ECU 30 and the braking ECU 40 may exchange information with each other through communication, and one of the driving ECU 30 and the braking ECU 40 may fail. This is due to the fact that it can be applied as a back up means for fail-safe implementation.

Subsequently, in step S40, the speed difference generated between the wheel W inside the swing and the wheel W outside the swing according to the turning of the vehicle V is calculated. The right front wheel motors 2, 3 are controlled and the braking ECU 40 controls the operation of the EMBs 11, 12, 21, 22.

Step S50 is a procedure for determining the difference between the current wheel speed of the turning vehicle V and the required wheel speed of the wheel inside the turning wheel W and the turning outer wheel W according to the turning degree. 30 and control of the braking ECU 40 are determined.

For example, if it is determined in step S50 that the required wheel speed> the current wheel speed, the braking ECU 40 does not perform the operation control of the EMBs 11, 12, 21, 22, as in step S60, and instead, the driving ECU 30 is driven. The left front wheel motor 2 and the right front wheel motor 3 are respectively controlled.

At this time, the driving ECU 30 is a rotational speed of the right front wheel motor (3) for driving the wheel (W) outside the turning compared to the rotation speed of the left front motor (2) for driving the wheel (W) inside the turning Will raise more.

This is because, as described above, the speed of the right wheel W should be made faster due to the difference in rotation radius between the left wheel W located inside the swing and the right wheel W located outside the swing.

The step S60 is continuously performed until the turning movement of the vehicle V is completed, and the turning completion is normally determined by the driving ECU 30 or the braking ECU 40 by the signal value of the steering angle sensor 61.

Meanwhile, if the required wheel speed> current wheel speed is not satisfied in step S50, it is determined whether the required wheel speed = current wheel speed is satisfied as in step S51.

For example, if the required wheel speed = the current wheel speed is satisfied in the step S51, control through the driving ECU 30 or the braking ECU 40 is not performed, whereas if the required wheel speed = the current wheel speed is not satisfied in the step S51 As in step S70, the control of the left and right front wheel motors 2 and 3 of the driving ECU 30 is not performed, but the braking ECU 40 controls the EMBs 11, 12, 21 and 22, respectively.

The control of the braking ECU 40 for the EMBs 11, 12, 21, and 22 is a relatively fast wheel at the speed difference according to the turning, that is, the left wheel W inside the turning and the right wheel outside the turning ( W) It is realized by lowering the wheel speed by driving and braking the EMB installed on the faster wheel.

The step S70 is continuously performed until the turning movement of the vehicle V is completed, and the turning completion is normally determined by the driving ECU 30 or the braking ECU 40 by the signal value of the steering angle sensor 61.

As described above, in the electric vehicle according to the present embodiment, the driving ECU 30 is left and right using steering information of the vehicle V detected by the steering angle sensor 61, the accelerator pedal sensor 62, and the brake pedal sensor 63. The driving ECU 30 may be maintained by controlling the driving device 1 of the front wheel to maintain turning stability, or the braking ECU 40 may control the front and rear wheel braking devices 10 and 20 to maintain turning stability. And fail-safe (Fail-Safe) as a backup concept of the braking ECU (40), and in particular the steering is implemented without the actuator and steering mechanism required in the steering device, such as MDPS or HPS or EHPS In addition to the cost savings, the steering angle can be greatly increased by restricting the steering mechanism, so that steering functions such as U-turns on narrow roads can be easily implemented.

1: Drive device 2,3: Left and right front wheel motor
10: Front wheel brake device 11, 12, 21, 22: EMB (Electic Mechanical Brake)
20: rear wheel braking device 30: driving ECU
40: braking ECU 50: steering wheel
60: sensor unit 61: steering angle sensor
62: accelerator pedal sensor 63: brake pedal sensor
Oc: center of rotation
V: Vehicle W: Wheel

Claims (10)

A driving device composed of at least one power source for driving a vehicle to drive a wheel and controlled by a driving ECU, and a braking device installed on the wheel to restrain the wheel to brake the vehicle and control the braking ECU when braking. In electric vehicles,
A steering wheel which the driver turns to and does not have a mechanical connection leading to the wheel to change the vehicle in the desired steering direction,
A steering angle sensor for detecting a rotation angle of the steering wheel handled by an internal algorithm of the driving ECU and the braking ECU, and transmitting the steering angle to the driving ECU and the braking ECU, respectively;
An acceleration pedal sensor which detects the depression stroke of the accelerator pedal of the vehicle processed by the internal algorithm of the driving ECU and the braking ECU and transmits it to the driving ECU and the braking ECU, respectively;
A brake pedal sensor that detects the depression stroke of the brake pedal of the vehicle processed by the internal algorithm of the driving ECU and the braking ECU and transmits it to the driving ECU and the braking ECU, respectively.
Electric vehicle with a sensor-sensitive steering device, characterized in that configured to include.
The method of claim 1, wherein the driving ECU and the braking ECU implement cooperative control through communication with each other so as to share information with each other, and when a failure occurs, the other side replaces a function of fail-safe. Electric vehicle with a sensor-sensitive steering device, characterized in that the (Safe) function is implemented.
The electric vehicle with a sensor-induced steering apparatus according to claim 2, wherein the driving ECU and the braking ECU communicate through a network such as CAN communication, MOST communication, or IDB1394 communication.
The driving apparatus of claim 1, wherein the driving device comprises a left front wheel motor for driving a left wheel of a front wheel and a right front wheel motor for driving a right wheel of a front wheel, and the left front wheel motor and the right front wheel motor are respectively driven by the driving ECU. An electric vehicle equipped with a sensory steering device, characterized in that the control independently.
The electric brake with an electric sensor-sensitive steering device according to claim 1, wherein the braking device is of an EMB (Electro Mechanical Brake) type installed on the left and right front wheels and the left and right wheels, respectively, and is independently controlled by the braking ECU. car.
A turning steering judging step of the driving ECU and the braking ECU receiving the rotation information of the steering wheel for turning the vehicle to recognize information about the depression stroke of the accelerator pedal and the depression stroke of the brake pedal;
After receiving the rotation information of the steering wheel and the information about the depression stroke of the accelerator pedal and the brake pedal, the driving ECU and the brake ECU determine the vehicle speed at the time of steering using an internal algorithm, and the wheel inside the turning and turning according to the turning A turning control judging step of calculating and calculating a speed difference generated between the outer wheels;
A turning control step of calculating a required wheel speed for turning stability on the basis of a speed difference calculated between the wheel inside the turning wheel and the wheel outside the turning, and comparing the request wheel speed with the current wheel speed of the turning vehicle;
According to the difference between the required wheel speed and the current wheel speed, the driving ECU controls the left front wheel motor and the right front wheel motor to change the rotational speeds of the wheel inside the turning wheel and the wheel outside the turning wheel, or the braking ECU turns the front wheel. A turning control completion step of changing the rotational speeds of the wheels inside the swing and the wheels outside the swing by controlling braking devices installed on the left rear wheel and the left and right wheels;
Steering control method of an electric vehicle using a sensor-sensitive steering device, characterized in that implemented.
7. The steering control method for an electric vehicle using a sensor-sensitive steering apparatus according to claim 6, wherein the turning control performing step performs the turning control completion step on the basis of determining that the requested wheel speed is greater than the current wheel speed.
8. The method of claim 7, wherein if the required wheel speed is greater than the current wheel speed, the driving ECU controls the left front wheel motor and the right front wheel motor to change the rotational speed of the wheel outside the turning faster than the wheel inside the turning. Steering control method for an electric vehicle using a sensor-sensitive steering device, characterized in that.
8. The method of claim 7, wherein if the request wheel speed is not greater than the current wheel speed, it is determined whether the request wheel speed and the current wheel speed are the same before performing the turning control completion step. Steering control method for an electric vehicle using a sensor-sensitive steering device, characterized in that determining whether to perform the step.
10. The method of claim 9, wherein if the request wheel speed and the current wheel speed is the same, the turning control is completed without performing the turning control completion step, whereas if the request wheel speed and the current wheel speed are not the same, the braking ECU is the front wheel rear wheel and the rear wheel. A steering control method of an electric vehicle using a sensor-sensitive steering device, characterized in that for controlling the braking device installed on the left and right wheels to change the rotational speed of the wheel inside the wheel and the wheel outside the wheel.

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