KR20230115683A - Steering control apparatus and controlling method for autonomous vehicle - Google Patents

Abstract

The present invention relates to a steering control device for autonomous driving and a control method thereof, and in case a failure occurs in either a steering angle sensor or a torque sensor during autonomous driving, a torque value is estimated from a weight sensor and a steering angle is estimated using a camera. Thus, autonomous driving is maintained by controlling the steering motor based on the control history, and redundancy for the steering angle sensor and the torque sensor is secured to prevent accidents and improve vehicle safety.

Description

Steering control device and control method for autonomous driving {STEERING CONTROL APPARATUS AND CONTROLLING METHOD FOR AUTONOMOUS VEHICLE}

The present invention relates to a steering control device for autonomous driving and a control method thereof for maintaining autonomous driving by estimating data for controlling a steering motor and controlling a driving direction even if a failure occurs in a sensor.

An autonomous vehicle is a vehicle that drives to a given destination by itself by recognizing the surrounding environment, determining the driving situation, and controlling the vehicle without driver intervention.

Since there are not only straight roads but also curved roads and round roads, and there are downhill or uphill roads, the vehicle needs to check the state of the road and change the driving direction while driving.

In addition, since a car does not travel alone on the road, it is necessary to determine the location of surrounding vehicles and to control driving while preventing collisions between vehicles according to changes in the location of surrounding vehicles.

The vehicle performs autonomous driving by controlling the driving direction by controlling the steering angle based on acquired information.

The vehicle controls the steering system by outputting a command steering angle according to the driving direction to be changed during autonomous driving. In controlling the steering system, the vehicle calculates the actual movement angle based on the detected values of the steering angle sensor and the torque sensor, and controls the steering system to adjust the angle of the wheel considering the current driving direction and the target driving direction. .

Meanwhile, when a failure occurs in one of the steering angle sensor and the torque sensor, the vehicle cannot control the steering device, and thus releases the autonomous driving mode and switches to the manual driving mode.

However, there is a problem in that it is difficult to immediately start driving even if a warning about the release of the autonomous driving mode is output while the driver is seated in the driver's seat. A driver needs time to adapt as he has to drive instantaneously, and an accident may occur because a situation in which he cannot drive may occur.

Vehicles are provided with various means to maintain autonomous driving in preparation for failure of these parts, but there is no means to prepare for failure of the steering angle sensor and torque sensor in steering control, so it is necessary to secure redundancy.

Korean Patent Registration No. 10-2286847, “Steering torque estimation apparatus and method” calculates the value of steering torque applied to a steering wheel by a driver using another sensor when a torque sensor fails, estimates the steering torque, and controls the steering motor .

However, this technology can be applied to a driving mode in which the driver manually operates the steering wheel or assists the driver in driving control, but cannot be applied to autonomous driving in which the driver does not operate the steering wheel.

Republic of Korea Patent No. 10-2286847

The present invention was created by the above necessity, and even if one of the steering angle sensor and the torque sensor fails during autonomous driving, the steering angle is estimated and the torque value is estimated to control the steering motor so as to maintain autonomous driving. An object of the present invention is to provide a steering control device for autonomous driving that secures redundancy according to control and a control method thereof.

In order to achieve the above object, a steering control device for autonomous driving according to the present invention includes a weight sensor for measuring a weight of a vehicle; A steering angle sensor and a torque sensor installed on the steering shaft of the steering wheel; A camera for taking an image of the front; a steering motor connected to the steering shaft to change the driving direction of the vehicle; and when a failure occurs in at least one of the steering angle sensor and the torque sensor, estimating a steering angle from the camera and images and estimating a rack thrust based on the weight of the vehicle measured from the weight sensor, thereby estimating the estimated steering angle. and a controller which retrieves matching data from pre-stored control history data based on the rack thrust and autonomously drives by driving the steering motor according to the matching data; includes

When a failure occurs in the torque sensor, the controller may generate assist torque by calculating the rack thrust corresponding to the weight and matching the steering angle of the steering angle sensor.

The controller classifies the state of the vehicle into a flat surface and a lower slope, and calculates the rack thrust to generate a steering force based on the weight.

The controller may recalculate the rack thrust force in response to a change in the weight of the vehicle.

An image processor for detecting a lane by analyzing a plurality of images captured by the camera, and calculating a rotation angle of the vehicle by comparing an image captured at a first time with an image captured at a second time based on the lane ; more includes

The controller may calculate the steering angle by determining the movement of the vehicle based on the rotation angle input from the image processor.

When a failure occurs in the steering angle sensor, the controller controls the steering motor by calculating the steering angle corresponding to the rotation angle calculated from the image processor and matching it with a measurement value of the torque sensor.

a memory for storing the control history data; The controller may further include, during normal driving, accumulating and storing data on the steering angle and torque measured from the steering angle sensor and the torque sensor in the memory as the control history data.

The controller may determine that a failure has occurred and generate a warning when the measured values of the steering angle sensor and the torque sensor are out of a set range or when the measured values are not input within a predetermined time.

In the control method of a steering control device for autonomous driving according to the present invention, when a failure occurs in at least one of a steering angle sensor and a torque sensor installed on a steering shaft of a steering wheel during autonomous driving, the controller generates and outputs a warning. doing; estimating a steering angle based on an image captured by a camera; estimating rack thrust based on the weight of the vehicle measured by the weight sensor; Searching for matching data from pre-stored control history data based on the estimated steering angle or the rack thrust; and controlling a driving direction of the vehicle by driving a steering motor according to the matching data. includes

The estimating of the steering angle may include, when a failure occurs in the steering angle sensor, detecting a lane by analyzing a plurality of images captured by the camera by an image processor; calculating a rotation angle of the vehicle by comparing an image captured at a first time with an image captured at a second time based on the lane; and determining, by the controller, movement of the vehicle based on the rotation angle and calculating the steering angle. includes

When a failure occurs in the steering angle sensor, the steering motor may be controlled by searching for data matching the measured value of the torque sensor and the steering angle calculated corresponding to the rotation angle.

The estimating of the rack thrust may include generating assist torque by calculating the rack thrust corresponding to the weight of the vehicle and matching it with a steering angle of the steering angle sensor when a failure occurs in the torque sensor.

The estimating of the rack thrust may include measuring, by the weight sensor, the weight of the vehicle; and calculating the rack thrust for generating a steering force based on the weight according to the state of the vehicle by classifying the state of the vehicle into a flat surface and a lower slope. includes

Accumulating and storing the control history data for the steering angle and torque measured from the steering angle sensor and the torque sensor in a memory during normal driving; Further, it is characterized in that it is determined that a failure has occurred when the measured values of the steering angle sensor and the torque sensor are out of a set range or when the measured values are not input within a predetermined time.

According to one aspect, the steering control apparatus and control method for autonomous driving of the present invention estimate the steering angle and torque values using a weight sensor and a camera when a failure occurs in either a steering angle sensor or a torque sensor during autonomous driving. It is possible to maintain autonomous driving by controlling the steering motor.

According to one aspect of the present invention, there is an effect of securing redundancy for a steering angle sensor and a torque sensor and improving safety by preventing an accident of a vehicle.

1 is a block diagram showing the configuration of an electric power steering device for autonomous driving according to an embodiment of the present invention.
2 is a diagram showing a control configuration of a steering control device for autonomous driving according to an embodiment of the present invention.
3 is a diagram illustrating a data flow of a steering control device for autonomous driving according to an embodiment of the present invention.
4 is a diagram referenced to explain a control method of a steering control device for autonomous driving according to an embodiment of the present invention.
5 is an exemplary diagram illustrating an example of a weight of a vehicle according to an embodiment of the present invention.
6 is a diagram referenced to explain steering force for each weight of a steering control device for autonomous driving according to an embodiment of the present invention.

Hereinafter, the present invention will be described with reference to the accompanying drawings.

In this process, the thickness of lines or the size of components shown in the drawings may be exaggerated for clarity and convenience of description. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of a user or operator. Therefore, definitions of these terms will have to be made based on the content throughout this specification.

1 is a block diagram showing the configuration of an electric power steering device for autonomous driving according to an embodiment of the present invention.

As shown in FIG. 1, the steering control device 100 includes a memory 180, a weight sensor 161, a steering angle sensor 162, a torque sensor 163, a camera 130, an image processor ( 140), a display 181, a speaker 192, a steering motor 120, and a controller (Electric Control Unit) (ECU) 110.

The controller (ECU) 110 and the image processor 140 include at least one microprocessor.

The steering control device 100 communicates with an external database (DB) (not shown) or an external server that provides road information through a communication module (not shown), and autonomous driving based on data stored in the memory 180. control to do The communication module performs CAN communication for transmitting and receiving data inside the vehicle, short-distance communication such as Bluetooth, and wireless communication for connection with an external server.

In addition, the steering control device 100 may operate in connection with a main processor (not shown) in which the controller (ECU) 110 controls overall operation of the vehicle.

The memory 180 stores control data for vehicle control, data detected through a plurality of sensors, and data transmitted and received through a communication module. Also, the memory 180 accumulates and stores command steering angles generated for autonomous driving.

A plurality of sensors detect vehicle speed and location information, measure information about the state of the vehicle, detect objects around the vehicle, and collect road information.

For example, the plurality of sensors include at least one of a Lidar, a radar, an ultrasonic sensor, an infrared sensor, a vehicle speed sensor, a distance sensor, and a temperature sensor to measure state information about the vehicle and to measure the surroundings of the vehicle. detects an object and measures the distance to the object.

Also, the plurality of sensors include a steering angle sensor 162 , a torque sensor 163 , and a weight sensor 161 .

The weight sensor 161 detects the weight of the vehicle. The weight sensor 161 may measure the weight when there is no occupant, and may detect the total weight including the weight of luggage stored in the trunk and the occupant. The weight sensor 161 may be installed at the center of gravity of the vehicle or at the center of the vehicle.

The steering angle sensor 162 is installed on a steering wheel (not shown) or a steering shaft connected to the steering wheel to measure a steering angle according to rotational manipulation of the steering wheel. The installation position of the steering angle sensor 162 may be changed according to the type of MDPS.

The torque sensor 163 detects torque applied between the steering shaft and the rack bar or between the steering shaft and the rack and pinion gear.

The camera 130 captures an image of the driving direction of the vehicle. A plurality of cameras 130 may be provided to capture images of the front, rear, and side of the vehicle, and in some cases may create a surround view by capturing 360-degree images centered on the vehicle. The camera 130 may include an image camera and an infrared camera.

The image processor 140 converts the image captured by the camera 130 into a specific format to generate image data. Also, the image processor 140 analyzes an image captured by the camera 130 to obtain information.

In addition, the image processor 140 detects objects around the vehicle, recognizes road signs to obtain road information, recognizes license plates of other vehicles located in the front and rear, and obtains information on the road being driven. .

The image processor 140 recognizes lanes or road boundaries from images and determines the driving direction of the vehicle. The image processor 140 calculates an angle between the lane and the driving direction of the vehicle.

The display 191 outputs vehicle information and driving information on a screen. Also, the display 191 displays an image captured by the camera 130 on the screen.

The speaker 192 outputs audio, and outputs sound effects, warning sounds, and voice guidance corresponding to the state of the vehicle.

The steering motor 120 transmits steering force to the rack bar or rack and pinion gear 123 so that the wheels move in response to the received steering angle. In addition, the steering motor 120 assists in rotation of the steering wheel. As the rack bar at the lower end of the steering motor 120 moves in response to the rotational direction of the steering wheel, the angle of the wheel (wheel) is changed and the driving direction is changed.

The controller (ECU) 110 determines the state of the vehicle in response to signals input from a plurality of sensors and controls the autonomous driving to the destination by controlling the steering motor 120 in response to the steering angle and torque value.

The controller (ECU) 110 determines abnormalities or failures of the sensors in response to signals input from a plurality of sensors.

The controller (ECU) 110 controls driving based on the camera 130 and the weight sensor 161 when a failure occurs in at least one of the steering angle sensor and the torque sensor.

The controller (ECU) 110 estimates rack thrust when data is input from the weight sensor 161 . The controller (ECU) 110 may estimate the rack thrust as a value obtained by subtracting the weight of the vehicle from the steering torque before the failure occurs.

When the sensor is normal, the controller (ECU) 110 calculates assist torque by matching the collected and stored data with the rack thrust, and applies the assist torque to the steering motor 120 to control driving.

In addition, the controller (ECU) 110 estimates the steering angle based on the calculated angle when the angle of the vehicle based on the lane is input from the image processor 140 based on the image of the camera 130 .

If the controller (ECU) 110 determines that the sensor is out of order, it generates a warning and transmits it to at least one of the display 191 and the speaker 192 . Accordingly, the display 191 outputs at least one of a message, an emoticon, an icon, and an image corresponding to the received warning. The speaker 192 outputs a warning sound or sound effect in response to the warning.

The controller (ECU) 110 outputs information about the failure of the sensor through the display 191 .

2 is a diagram showing a control configuration of a steering control device for autonomous driving according to an embodiment of the present invention.

As shown in FIG. 2 , the steering control device 100 changes the driving direction of the vehicle by controlling the electric steering device. The electric power steering device 10 is MDPS (Motor-Driven Power Steering) and is described by taking an R type as an example, but various forms may be applied depending on its operation method.

The electric steering device includes a steering wheel 121, a steering angle sensor 162 and a torque sensor 163 installed on a steering shaft that transmits rotational force of the steering wheel 121, a steering gear 122, a steering motor 120, a steering It includes a rack bar or a rack and pinion gear 123 that changes the direction of the wheel according to the driving of the motor 120 .

The electric power steering device 10 assists the operation of the steering wheel 121 when the driver manually operates the steering wheel 121, and responds to the command steering angle applied from the controller (ECU) 110 when the autonomous driving mode is set. The driving direction of the vehicle is controlled by driving the steering motor 120.

The steering motor 120 is mounted on the steering gear 122 and transmits driving force to the rack and pinion gear 123 . The steering motor 120 recognizes a steering value when steering by the steering wheel 11 to drive the rack and pinion gear 123 and operates without delay in response to the steering force.

The rack and pinion gear 123 is driven by the steering motor 120 to move a wheel connected to the shaft according to a steering value.

The controller (ECU) 110 is operated by the applied controller (ECU) voltage S5, and applies the sensor voltage S2 to the steering angle sensor 162 and the torque sensor 163 so that the steering angle sensor 162 and the torque This causes the sensor 163 to operate.

The controller (ECU) 110 controls the sensor signal S1 input from the steering angle sensor 162 and the torque sensor 163, the vehicle speed S6 input from the vehicle speed sensor, and the vehicle state signal S7 input from a plurality of sensors. ), a driving direction is set so that the vehicle travels to the set destination, and a corresponding steering angle is set to apply a motor voltage (S3) of a certain magnitude to the steering motor 120.

The controller (ECU) 110 detects the motor position when the steering motor 120 is driven (S4), determines the current steering angle, sets the steering angle based on this, and applies motor voltage to the steering motor 120, thereby driving the vehicle. change the driving direction

3 is a diagram illustrating a data flow of a steering control device for autonomous driving according to an embodiment of the present invention.

3, the controller (ECU) 110 controls the steering angle sensor 162 or torque sensor 163 based on the sensor signal S1 applied from the steering angle sensor 162 or torque sensor 163. detect a fault

When a failure occurs in the sensor, the controller (ECU) 110 uses data matched to the current situation from the control history data in a normal state based on the video signal, the weight value of the weight sensor 161, and the control history data. to calculate the assist torque for controlling the driving direction, and apply the motor voltage to the steering motor 120 accordingly.

The controller (ECU) 110 controls the steering motor 120 by estimating the rack thrust from the measurement value of the weight sensor 161 when a failure occurs in the steering angle sensor 162 or the torque sensor 163.

In addition, the controller (ECU) 110 controls the steering motor 120 based on an angle input from the image processor 140 based on an image captured by the camera 130 .

During steering control, the controller (ECU) 110 accumulates control history data for the measured values of the steering angle and the torque sensor, stores them in the memory 180, and calculates assist torque based on the previously stored control history data when the sensor fails. do.

The controller (ECU) 110 compares the weight value measured by the weight sensor 161 with the weight value measured before the sensor fails to search for matching data. The controller (ECU) 110 calculates the torque required when the steering angle is moved by 1 degree or the rack thrust required to move the rack and pinion gear based on the data stored in the riding weight measured by the weight sensor 161.

In addition, the controller (ECU) 110 analyzes the image of the camera 130 through the image processor 140 to detect the lane, and determines whether the driving direction of the vehicle has moved by the set amount based on the lane or the degree of rotation.

Since the controller (ECU) 110 cannot check the actual amount of movement through the steering angle sensor 162, it determines the actual degree of rotation through the changed angle using the camera 130. In some cases, the controller (ECU) 110 may use a sensor installed in the front of the vehicle.

The controller (ECU) 110 controls the steering motor 120 by calculating assist torque by searching for data that matches the control history data based on the rack thrust and the angle confirmed through the camera.

4 is a diagram referenced to explain a control method of a steering control device for autonomous driving according to an embodiment of the present invention.

As shown in FIG. 4 , the controller (ECU) 110 receives sensor signals during autonomous driving and controls the driving direction (S310).

The controller (ECU) 110 receives sensor signals from the steering angle sensor 162 and the torque sensor 163, checks whether the vehicle is driving according to the terrain steering angle, calculates the next command steering angle, and operates the steering motor 120 A voltage of a certain magnitude is applied to

When the input sensor signal is out of the normal range, the controller (ECU) 110 determines that the sensor is out of order (S320). In addition, the controller (ECU) 110 may determine that a sensor is out of order when a sensor signal is not input for a predetermined period of time or longer.

If the controller (ECU) 110 determines that the sensor is faulty, it generates a warning about the sensor fault and applies it to the display 191 and the speaker 192 . Accordingly, the display 191 outputs a warning message or warning image for sensor failure on the screen, and the speaker 192 outputs a warning sound or warning voice guide for sensor failure.

The controller (ECU) 110 requests the rotation angle of the vehicle from the image processor 140 and applies a voltage to the weight sensor 161 .

The image processor 140 analyzes the image captured by the camera 130 according to the request of the controller (ECU) 110, compares the image of the first time and the image of the second time, and calculates the rotation angle according to the movement of the vehicle. yields

The image processor 140 detects a lane from the image, calculates an angle between the lane and the vehicle, and then compares a plurality of images and calculates a difference between the calculated angles as a rotation angle of the vehicle. The image processor 140 calculates the degree of movement of the vehicle to the left or the right with respect to the lane as a rotation angle and applies it to the controller (ECU) 110.

The controller (ECU) 110 estimates the steering angle, which is the angle at which the vehicle turns left or right when the vehicle controls the steering motor according to the command steering angle, based on the rotation angle input from the image processor 140. Do (S330).

The weight sensor 161 is driven by the applied voltage, detects vehicle weight and ride weight of the vehicle, and inputs them to the controller (ECU) 110 (S340).

The controller (ECU) 110 searches for control history data corresponding to the weight of the vehicle measured by the centering sensor (S350), and calculates rack thrust, which is the force required to move the steering angle by 1 degree, from matching data with matching weight values. do.

The controller (ECU) 110 recalculates the rack thrust in response to a change in the weight of the vehicle or a change in the state of the vehicle relative to the ground.

In addition, the controller (ECU) 110 searches for previously stored control history data and calculates a command steering angle and torque value based on the matching data (S360).

The controller (ECU) 110 generates assist torque in response to the command steering angle and torque value (S370), and controls the steering motor 120 by applying a certain amount of current based on the assist torque (S380).

As the steering motor 120 operates, the rack and pinion gear 123 operates, and the wheels move accordingly, thereby changing the driving direction of the vehicle.

Accordingly, the steering control device does not switch to manual driving even if a steering angle sensor or a torque sensor fails, and maintains autonomous driving based on the image of the camera and the weight value.

5 is an exemplary diagram illustrating an example of a weight of a vehicle according to an embodiment of the present invention.

The controller (ECU) 110 calculates rack thrust based on the weight value received from the weight sensor 161.

As shown in FIG. 5 , the controller (ECU) 110 determines the weight value received from the weight sensor 161, which is a weight change when the vehicle is located on a flat surface or on a 20% lower slope. Weight is measured differently depending on the vehicle model.

For example, when the complete vehicle kerb weight (CVW) of the vehicle is 1842 kg in total, it is measured as 502 kg for the front wheels and 451.5 kg for the rear wheels on a flat surface, and 454.5 kg for the front wheels and 434 kg for the rear wheels on a 20% slope.

In addition, when the Gross Vehicle Weight (GVW) of the vehicle is a total of 2471 kg, the front wheels are 626.5 kg and the rear wheels are 609.5 kg in the case of flat terrain, and the front wheels are 618 kg and the rear wheels are 617.5434 kg in the case of a 20% slope.

In the case of an electric vehicle model, the total vehicle weight is 2858, which is higher than that of a general vehicle.

The controller (ECU) 110 varies according to the condition of the ground on which the vehicle is located, the weight of the occupant, and the like, and also varies the magnitude of torque for generating steering force.

When the torque sensor 163 fails, the controller (ECU) 110 detects the empty vehicle weight and the gross vehicle weight of the vehicle through the weight sensor 161 and calculates rack thrust in response thereto.

6 is a diagram referenced to explain steering force for each weight of a steering control device for autonomous driving according to an embodiment of the present invention.

As shown in FIG. 6, in response to the rack thrust and steering force, the left and right sides at 90% of the steering force are If it is 4.5NM and the steering force is 4.8NM and 4.8NM at the 100% point, respectively, the rack thrust becomes 1589 and 1479. In addition, when the steering force is 4.4 and 4.4 on the left and right at the 90% point and 4.8 and 4.8NM at the 100% steering force point, the rack thrust is 1550 and 1523 on the left and right, respectively.

In addition, when the steering force is 4.0 and 3.9 at the 90% point and 4.3 and 4.1NM at the 100% point, the rack thrust is 1258 and 1143 on the left and right, respectively. The end steering angle for an angular velocity of 90 is 447 degrees and 439 degrees for the left and right, respectively.

In addition, the controller (ECU) 110 may calculate the rack thrust based on the weight of the vehicle, particularly the empty vehicle weight, for stop catch-up to maintain the stopped state when the vehicle is stopped on a slope.

As such, the controller (ECU) 110 calculates the rack thrust based on the weight of the vehicle measured through the weight sensor 161 when a failure occurs in at least one of the steering angle sensor and the torque sensor of the vehicle, and the camera By calculating the actual rotation angle of the vehicle through 130 and the image processor 140, the steering motor 120 is driven to control the driving direction.

Accordingly, the present invention can control the driving direction of the vehicle while maintaining the autonomous driving mode without releasing it even if a failure occurs in at least one of the steering angle sensor and the torque sensor of the vehicle.

Although the present invention has been described with reference to the embodiments shown in the drawings, it should be noted that this is only exemplary and various modifications and equivalent other embodiments are possible from those skilled in the art to which the technology pertains. will understand Therefore, the true technical protection scope of the present invention should be defined by the claims below.

110: controller (ECU) 120: steering motor
121: steering wheel 122: steering gear
130: camera 140: image processor
161: weight sensor 162: steering angle sensor
163: torque sensor 180: memory

Claims (15)

A weight sensor for measuring the weight of the vehicle;
A steering angle sensor and a torque sensor installed on the steering shaft of the steering wheel;
A camera for taking an image of the front;
a steering motor connected to the steering shaft to change the driving direction of the vehicle; and
When a failure occurs in at least one of the steering angle sensor and the torque sensor, the steering angle is estimated from the camera and the image and the rack thrust is estimated based on the weight of the vehicle measured from the weight sensor, and the estimated steering angle or a controller that searches for matching data from pre-stored control history data based on the rack thrust and autonomously drives by driving the steering motor according to the matching data; Steering control device comprising a. According to claim 1,
Wherein the controller generates assist torque by calculating the rack thrust corresponding to the weight and matching the steering angle of the steering angle sensor when a failure occurs in the torque sensor. According to claim 1,
The steering control device according to claim 1 , wherein the controller classifies the state of the vehicle into flat terrain and a lower slope and calculates the rack thrust to generate steering force based on the weight. According to claim 1,
Wherein the controller recalculates the rack thrust in response to a change in the weight of the vehicle. According to claim 1,
An image processor for detecting a lane by analyzing a plurality of images captured by the camera, and calculating a rotation angle of the vehicle by comparing an image captured at a first time with an image captured at a second time based on the lane ; Steering control device further comprising a. According to claim 5,
The steering control device, characterized in that the controller calculates the steering angle by determining the movement of the vehicle based on the rotation angle input from the image processor. According to claim 5,
When a failure occurs in the steering angle sensor, the controller controls the steering motor by calculating the steering angle corresponding to the rotation angle calculated from the image processor and matching it with the measured value of the torque sensor. Device. According to claim 1,
a memory for storing the control history data; Including more,
The steering control device according to claim 1 , wherein the controller accumulates and stores data on the steering angle and torque measured from the steering angle sensor and the torque sensor in the memory as the control history data during normal driving. According to claim 1,
Wherein the controller determines that a failure has occurred and generates a warning when the measured values of the steering angle sensor and the torque sensor are out of a set range or when the measured values are not input within a predetermined time. generating and outputting, by a controller, a warning when a failure occurs in at least one of a steering angle sensor and a torque sensor installed on a steering shaft of a steering wheel during autonomous driving;
estimating a steering angle based on an image captured by a camera;
estimating rack thrust based on the weight of the vehicle measured by the weight sensor;
Searching for matching data from pre-stored control history data based on the estimated steering angle or the rack thrust; and
controlling a driving direction of the vehicle by driving a steering motor according to the matching data; Control method of a steering control device comprising a. According to claim 10,
The step of estimating the steering angle,
detecting a lane by analyzing a plurality of images captured by the camera by an image processor when a failure occurs in the steering angle sensor;
calculating a rotation angle of the vehicle by comparing an image captured at a first time with an image captured at a second time based on the lane; and
determining, by the controller, movement of the vehicle based on the rotation angle and calculating the steering angle; Control method of a steering control device comprising a. According to claim 11,
When a failure occurs in the steering angle sensor, the steering motor is controlled by searching for data matching the measured values of the steering angle and the torque sensor calculated in correspondence with the rotation angle to control the steering control device. According to claim 10,
In the step of estimating the rack thrust,
and generating assist torque by calculating the rack thrust corresponding to the weight of the vehicle and matching it with a steering angle of the steering angle sensor when a failure occurs in the torque sensor. According to claim 13,
In the step of estimating the rack thrust,
measuring the weight of the vehicle by the weight sensor; and
calculating the rack thrust for generating a steering force based on the weight according to the state of the vehicle by classifying the state of the vehicle into a flat surface and a lower slope; Control method of a steering control device comprising a. According to claim 10,
Accumulating and storing the control history data for the steering angle and torque measured from the steering angle sensor and the torque sensor in a memory during normal driving; Including more,
A control method of a steering control device, characterized in that it is determined that a failure has occurred when the measured value of the steering angle sensor or the torque sensor is out of a set range or when the measured value is not input within a predetermined time.

Images