JP6627261B2 - Automatic steering device - Google Patents

Description

  The present invention relates to an automatic steering device.

  2. Description of the Related Art Conventionally, there is an automatic steering device that enables automatic steering of a vehicle by automatically steering a steering mechanism without requiring a driver to operate a steering wheel. In the automatic steering device, in order to automatically steer the steering mechanism, while performing position control to perform feedback so as to eliminate the deviation between the target steering wheel steering angle and the actual steering wheel steering angle, The current supplied to the motor, which is the source of the torque for steering the steering mechanism, is controlled.

  During the automatic steering of the vehicle by the automatic steering device, unintended vibration may occur in the vehicle, and there is a device capable of suppressing such unintended vibration (for example, Patent Document 1). According to Patent Document 1, when unintended vibration is applied to the vehicle during the automatic steering, the position control is separated, the vibration component is suppressed only by the current control, and then, the control returns to the automatic steering as the position control again. There is a description to do.

Japanese Patent Application No. 2015-007687

  By the way, in Patent Document 1, the vibration component is suppressed only by the current control, and thereafter, the control immediately returns to the automatic steering which is the position control. However, even if the vibration component can be suppressed, for example, the deviation between the target steering wheel steering angle and the actual steering wheel steering angle may be large. At that time, if the vehicle immediately returns to the automatic steering as the position control, the steering wheel is steered suddenly, and an unexpected situation may occur for the driver.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an automatic steering device that can suppress unstable control relating to automatic steering.

To solve the above problems, the invention according to claim 1, based on the command status amount input in every predetermined period, comprising a first control hand stage performs state quantity control of the motor of the steering mechanism, The first control means includes: a first control unit including a position control unit, a speed control unit, and a current control unit of an actuator of a steering mechanism including the motor; a speed control unit of an actuator of the steering mechanism; And a second control unit including a current control unit and a third control unit including a current control unit of an actuator of the steering mechanism. The first control unit includes: The first constituent means, the second constituent means, or the third constituent means as the state quantity control in accordance with a change in the state of the vehicle whether or not the vehicle is in a straight traveling state and the presence or absence of vehicle vibration. And select In an automatic steering device that generates a command state quantity input for each cycle, it is determined whether an absolute value of a difference between the automatic steering command steering angle, which is the command state quantity, and an actual steering angle is equal to or greater than a predetermined steering angle. further comprising a determination hand stage, said first control means, in response to a change in state of the vehicle, after selecting the third configuration means from said first configuration means, by a change of state of the vehicle In the case where the first constituent means is selected again, while the determining means determines that the absolute value of the difference between the automatic steering command steering angle and the actual steering angle is equal to or larger than the predetermined steering angle, The gist is to select the second constituent means.

In automatic operation device of the present claims, and an automatic steering command steering angle is commanded state quantity, the absolute value of the difference between the actual steering angle is further provided with a judging hand stage whether or not a predetermined steering angle or more, the first The control means selects the third constituent means from the first constituent means according to the change in the state of the vehicle , and then selects the first constituent means again according to the change in the state of the vehicle. The second configuration means is selected while the determination means determines that the absolute value of the difference between the automatic steering command steering angle and the actual steering angle is equal to or greater than the predetermined steering angle.

  That is, when the abnormality of the vehicle is determined based on the determination condition of the vehicle, the first constituent means (position control unit + speed control unit + current control unit: automatic steering control) having a slow control cycle outputs a third control cycle having a fast control cycle. (Current control unit: vehicle vibration suppression control) is selected to cancel the abnormal state early. However, when the abnormal state is canceled and the operation is immediately returned to the first component, if the positional deviation is excessively large, sudden steering is turned off, which is dangerous. Therefore, when the determining means determines that the absolute value of the difference between the automatic steering command steering angle and the actual steering angle is equal to or larger than the predetermined steering angle, the second component means is not immediately returned to the first component means. By selecting (speed control unit + current control unit: steering deviation suppression control) and controlling the motor speed, that is, the amount of change in the motor position, a sudden change in the position deviation is suppressed. As a result, sudden steering can be prevented, and a safe steering system can be configured.

The invention according to claim 2 further includes a vehicle speed detection unit that detects a vehicle speed, wherein the first control unit determines that an absolute value of a difference between the automatic steering command steering angle and the actual steering angle is determined by the determination unit. As a result of the determination that the steering angle is equal to or larger than the predetermined steering angle, when the second component is selected, the speed of the speed control unit is limited to suppress a rapid change in the amount of change in the state variable control of the motor. The gist of the present invention is to determine a speed limit value to be performed based on a map that defines a relationship between the speed limit value and the vehicle speed.

  That is, as described above, when the abnormal state is canceled and the user immediately tries to return to the original first configuration means, and if the positional deviation is excessive, the sharp steering is turned off and there is a danger. is there. Therefore, if the determining means determines that the absolute value of the difference between the automatic steering command steering angle and the actual steering angle is equal to or greater than the predetermined steering angle, the second control means may immediately return to the first constituent means. Instead, by selecting the second component and controlling the motor speed, that is, the amount of change in the motor position, a sudden change in the position deviation is suppressed.

  Further, when the vehicle speed is high, it is more dangerous to quickly reduce the excessive positional deviation by the second component. Therefore, when the vehicle speed is high, the speed limit value of the speed control system is reduced to avoid reducing an excessive positional deviation at a high speed. By doing so, a safer steering system can be configured.

  Advantageous Effects of Invention According to the present invention, it is possible to provide an automatic steering device capable of suppressing the control related to automatic steering from becoming unstable.

FIG. 1 is a schematic configuration diagram of an automatic steering device according to an embodiment. FIG. 2 is a control block diagram of an EPS ECU of the automatic steering device according to the embodiment. 5 is a flowchart showing a processing procedure of the EPS microcomputer according to the embodiment. 4 is a speed limit value / vehicle speed map according to the embodiment.

Hereinafter, an embodiment of the present invention embodied in an automatic steering device 1 including a column-type electric power steering device (hereinafter, referred to as EPS) will be described with reference to the drawings.
As shown in FIG. 1, the automatic steering device 1 according to the present embodiment, which performs a steering angle control of a steering mechanism based on a command steering angle (command state quantity) input every predetermined cycle, is input every predetermined cycle. An automatic steering ECU 29 that is a higher-level controller that transmits an automatic steering command steering angle θs * to the EPS ECU 28 via the in-vehicle network 90 (CAN) is provided.

  Next, the EPS of the present embodiment will be described. As shown in FIG. 1, in the EPS of the present embodiment, a steering shaft 3 to which a steering 2 is fixed is connected to a rack shaft 5 via a rack and pinion mechanism 4. The rotation of the steering shaft 3 accompanying the steering operation is converted into a reciprocating linear motion of the rack shaft 5 by the rack and pinion mechanism 4.

  The steering shaft 3 of the present embodiment is formed by connecting a column shaft 8, an intermediate shaft 9, and a pinion shaft 10. The reciprocating linear motion of the rack shaft 5 associated with the rotation of the steering shaft 3 is transmitted to a knuckle (not shown) via tie rods 11 connected to both ends of the rack shaft 5, and thereby the steering angle of the steered wheels 12. Has been changed.

  The EPS includes an actuator 20 as a steering force assisting device that applies an assist force for assisting a steering operation to a steering system by using the motor 21 as a drive source, and an EPS ECU 28 that controls the operation of the actuator 20.

  The actuator 20 of the present embodiment is a column-type actuator, and a motor 21 as a driving source thereof is drivingly connected to the column shaft 8 via a speed reduction mechanism 23. The rotation of the motor 21 is reduced by the reduction mechanism 23 and transmitted to the column shaft 8, so that the motor torque is applied to the steering system as an assist force.

  The automatic steering ECU 29 is connected to a GPS 24 such as a car navigation system, a vehicle speed sensor 25 serving as vehicle speed detecting means, a steering angle sensor 26, and a yaw rate sensor 27. On the other hand, the motor rotation angle sensor 22 is connected to the EPS ECU 28.

Next, an electrical configuration of the automatic steering device 1 according to the present embodiment will be described.
FIG. 2 shows an automatic steering ECU 29 and an EPS ECU 28 of the automatic steering device 1 according to the present embodiment.
It is a control block diagram of. First, the electrical configuration of the automatic steering ECU 29 will be described.
As shown in the figure, the automatic steering ECU 29 includes upper position information θcon transferred from the GPS 24, a vehicle speed SP detected from the vehicle speed sensor 25, an actual steering angle θs detected from the steering angle sensor 26, and a yaw rate sensor 27. Is input.

Further, the automatic steering ECU 29 includes an automatic steering mode switching flag FLG1 (automatic speed control) output from a speed control execution determination unit 65 (described later), which is a determination unit of the EPS ECU 28, and a current control execution determination unit 67 (described below). The automatic steering mode switching flag FLG2 (automatic current control) output from the control unit is input via the in-vehicle network 90 (CAN).

The automatic steering microcomputer 30 includes a command steering angle generation unit 31 that generates an optimum automatic steering command steering angle θs * based on the vehicle speed SP and the upper position information θcon. Then, the automatic steering ECU 29 calculates the automatic steering command steering angle θs * generated by the command steering angle generator 31, the actual steering angle θs detected by the steering angle sensor 26, and the vehicle speed S detected by the vehicle speed sensor 25.
P and the yaw rate γ detected from the yaw rate sensor 27 are transmitted to the in-vehicle network 9.
0 (CAN) to the EPSECU 28.

Next, an electrical configuration of the EPS ECU 28 of the present embodiment will be described.
As shown in the figure, the EPS ECU 28 includes an EPS microcomputer 50 that constructs a control system at the time of automatic steering, and a drive circuit that supplies drive power to the motor 21 that is the drive source of the actuator 20 based on the motor control signal. A section 57 and a current sensor 61 for detecting the actual motor current Ir supplied to the motor 21 are provided.

The drive circuit section 57 is a known PWM inverter (not shown) formed by connecting two arms corresponding to each phase in parallel with a pair of switching elements connected in series as a basic unit (arm). The motor control signal output from the EPS microcomputer 50 defines the on-duty ratio of each switching element included in the drive circuit unit 57. A motor control signal is applied to the gate terminal of each switching element, and each switching element is turned on / off in response to the motor control signal.
Is generated based on the power supply voltage of the motor and output to the motor 21.

  Each control block described below is realized by a computer program executed by the EPS microcomputer 50. The EPS microcomputer 50 detects each of the above-mentioned state quantities at a predetermined sampling period, and executes a calculation process shown in each control block below at each predetermined period to generate a motor control signal.

  Next, each function of the EPS ECU 28 will be described in detail. The EPS microcomputer 50, which is a first control unit, converts the automatic steering command steering angle θs * transmitted at a predetermined cycle into an automatic steering command steering angle / automatic steering command motor rotation angle data converter 59. This is converted into an automatic steering command motor rotation angle θr *.

  Then, the EPS microcomputer 50 subtracts the actual motor rotation angle θr from the automatic steering command motor rotation angle θr * by the position subtractor 70 to generate a motor rotation angle deviation value Δθr. Next, the EPS microcomputer 50 inputs the motor rotation angle deviation value Δθr to the position control unit 51 that performs state quantity control in the subsequent stage, executes proportional control (P control), and issues a command generated by the position control unit 51. The motor rotation speed data ωr0 * is output.

  The automatic steering mode switching unit 52 (speed control) has an automatic steering mode switching unit a contact 52a, an automatic steering mode switching unit b contact 52b, and an automatic steering mode switching unit c contact 52c for output. are doing. Then, the command motor rotation speed data ωr0 * generated by the position control unit 51 is input to the automatic steering mode switching unit a contact 52a of the subsequent automatic steering mode switching unit 52 (speed control).

  On the other hand, the automatic steering command steering angle θs * and the actual steering angle θs are transmitted from the automatic steering ECU 29 to the speed control execution determination unit 65 in the EPS microcomputer 50 via the in-vehicle network 90 (CAN). When the absolute value of the difference between the automatic steering command steering angle θs * and the actual steering angle θs is larger than a predetermined steering angle 1 (θs0), the speed control execution determination unit 65 determines whether the automatic steering mode switching flag FLG1 (automatic speed Control) is turned ON.

  The ON signal of the automatic steering mode switching flag FLG1 (automatic speed control) is transmitted to the automatic steering ECU 29 via the in-vehicle network 90 (CAN). Further, the ON signal of the automatic steering mode switching flag FLG1 (automatic speed control) is also input to the automatic steering mode switching unit 52 (speed control), and the automatic steering mode switching unit 52 (speed control) automatically switches the effective contact. The mode switching part a contact 52a is switched to the automatic steering mode switching part b contact 52b.

  Next, the speed command generation unit 66 generates optimal automatic steering command motor rotation speed data ωr1 * to execute speed control. More specifically, the speed command generation unit 66 generates the automatic steering command motor rotation speed data ωr1 * based on the automatic steering command steering angle θs * input from the automatic steering ECU 29. Here, the automatic steering command motor rotation speed data ωr1 * is generated in consideration of a speed limit value based on the vehicle speed SP calculated from a speed limit value / vehicle speed map (not shown).

  That is, when the vehicle speed SP is high, the speed limit value of the speed control system is reduced to avoid suddenly reducing excessive position deviation. By doing so, a safer steering system can be configured. Then, the automatic steering command motor rotation speed data ωr1 * is input to the automatic steering mode switching unit b contact 52b, passes through the automatic steering mode switching unit c contact 52c, and becomes the final command motor rotation speed data ωr *.

  Then, the EPS microcomputer 50 subtracts the actual motor rotation speed ωr from the final command motor rotation speed data ωr * by the speed subtractor 71 to generate a motor rotation speed deviation value Δωr. The actual motor rotation speed ωr is generated by differentiating the actual motor rotation angle θr detected by the motor rotation angle sensor 22 with the differentiator 58.

  Next, the EPS microcomputer 50 inputs the motor rotation speed deviation value Δωr to the speed control unit 53 that performs state quantity control in the subsequent stage, executes proportional control + integral control + differential control (PID control), and executes the speed control unit. 53 to output the command motor current data Ir0 *.

  The automatic steering mode switching unit 54 (current control) has an automatic steering mode switching unit a contact 54a, an automatic steering mode switching unit b contact 54b, and an automatic steering mode switching unit c contact 54c for output. are doing. The command motor current data Ir0 * generated by the speed control unit 53 is input to the automatic steering mode switching unit a contact 54a at the subsequent stage.

  On the other hand, an automatic steering command steering angle θs *, an actual steering angle θs, and a yaw rate γ are transmitted from the automatic steering ECU 29 to the current control execution determination unit 67 in the EPS microcomputer 50 via the in-vehicle network 90 (CAN). The current control execution determination unit 67 determines that the absolute value of the difference Δθs * between the previous value and the current value of the automatic steering command steering angle is smaller than a predetermined command steering angle deviation 1 (Δθs * 0), and that the yaw rate γ signal has a vibration. If they are superimposed, the automatic steering mode switching flag FLG2 (automatic current control) is turned on.

  The ON signal of the automatic steering mode switching flag FLG2 (automatic current control) is transmitted to the automatic steering ECU 29 via the in-vehicle network 90 (CAN). Further, the ON signal of the automatic steering mode switching flag FLG2 (automatic current control) is also input to the automatic steering mode switching unit 54 (current control), and the automatic steering mode switching unit 54 (current control) automatically switches the effective contact. The mode switching part a contact 54a is switched to the automatic steering mode switching part b contact 54b.

  Next, the current command generation unit 68 generates optimal automatic steering command motor current data Ir1 * to execute current control. Then, the automatic steering command motor current data Ir1 * is input to the automatic steering mode switching unit b contact 54b, passes through the automatic steering mode switching unit c contact 54c, and becomes the final command motor current data Ir *.

  Next, the EPS microcomputer 50 subtracts the final command motor current data Ir * input from the automatic steering mode switching unit 54 and the actual motor current Ir detected from the current sensor 61 by the current subtractor 72, and A deviation value ΔIr is generated.

  Then, the microcomputer 50 for EPS inputs the motor current deviation value ΔIr to the current control unit 55 which performs state quantity control at the subsequent stage, executes proportional control + integral control + differential control (PID control), and executes the motor voltage command V *. Generate The motor voltage command V * generated by the current control unit 55 is input to a PWM output unit 56 at the subsequent stage. The PWM output unit 56 generates a motor control signal for driving the drive circuit unit 57 at the subsequent stage, and outputs the generated signal to the motor 21.

Next, a processing procedure of the EPS microcomputer 50 in the present embodiment will be described with reference to FIG.
First, the EPS microcomputer 50 determines whether or not the vehicle is in a straight traveling state (step S101). Then, when the EPS microcomputer 50 determines that the vehicle is in the straight traveling state (step S101: YES), the microcomputer 50 determines whether or not there is vehicle vibration (step S102). If the EPS microcomputer 50 determines that there is vehicle vibration (step S102: YES), the microcomputer 50 executes current control (third component: vehicle vibration suppression control) (step S103).

  Subsequently, the EPS microcomputer 50 determines whether the vehicle vibration is continuing (Step S104). When the EPS microcomputer 50 determines that the vehicle vibration is not continued (step S104: NO), the absolute value of the difference between the automatic steering command steering angle θs * and the actual steering angle θs is equal to the predetermined steering angle. It is determined whether the angle is equal to or larger than the angle 1 (θs0) (step S105).

  When the absolute value of the difference between the automatic steering command steering angle θs * and the actual steering angle θs is equal to or greater than the predetermined steering angle 1 (θs0) (step S105: YES), the EPS microcomputer 50 determines the speed. The control (second configuration means: steering deviation suppression control) is executed (step S106). Next, the EPS microcomputer 50 determines whether the absolute value of the difference between the automatic steering command steering angle θs * and the actual steering angle θs is equal to or smaller than a predetermined steering angle 2 (θs1) (Step S107).

  When the absolute value of the difference between the automatic steering command steering angle θs * and the actual steering angle θs is equal to or smaller than the predetermined steering angle 2 (θs1) (step S107: YES), the EPS microcomputer 50 performs the position control (step S107: YES). First constituent means: automatic steering control) is executed (step S108), and the process ends. On the other hand, when the absolute value of the difference between the automatic steering command steering angle θs * and the actual steering angle θs is larger than the predetermined steering angle 2 (θs1) (step S107: NO), the EPS microcomputer 50 performs the speed control ( Second component means: steering deviation suppression control) is executed (step S106). If it is determined that the vehicle vibration is continuing (step S104: YES), the EPS microcomputer 50 executes current control (third component: vehicle vibration suppression control) (step S103).

  On the other hand, the EPS microcomputer 50 determines that the vehicle is not in the straight traveling state (step S101: NO), determines that there is no vehicle vibration (step S102: NO), or sets the automatic steering command steering angle θs *. If the absolute value of the difference between the actual steering angle θs and the actual steering angle θs is smaller than the predetermined steering angle 1 (θs0) (step S105: NO), the position control (first configuration means: automatic steering control) is executed. (Step S108), and the process ends.

Next, a speed limit value / vehicle speed map according to the present embodiment will be described with reference to FIG.
The vertical axis in FIG. 4 is the speed limit value (%), and the horizontal axis is the vehicle speed (m / s). As the speed limit value is smaller, the speed of the speed control system is limited to a smaller value. In this embodiment, the speed limit value is gradually reduced as the vehicle speed SP increases (increases).

  In this embodiment, the vehicle vibration is suppressed by switching to the current control system. However, even if the vehicle vibration is suppressed, before returning to the position control system that is the automatic steering, the speed control execution determination unit 65 determines that the absolute value of the difference between the automatic steering command steering angle θs * and the actual steering angle θs is a predetermined value. Is determined to be greater than or equal to the steering angle 1 (θs0).

  Then, when the speed control execution determination unit 65 determines that the absolute value of the difference between the automatic steering command steering angle θs * and the actual steering angle θs is equal to or larger than the predetermined steering angle 1 (θs0), the speed control execution determination unit 65 immediately determines the position control system. Rather than returning, by controlling the motor speed, that is, the amount of change in the motor position, by selecting a speed control system, a sudden change in the position deviation is suppressed.

  Further, when the vehicle speed is high, it is more dangerous to quickly reduce the excessive positional deviation in the speed control system. Therefore, when the vehicle speed is high, the speed limit value of the speed control system is reduced to avoid reducing an excessive positional deviation at a high speed. By doing so, a safer steering system can be configured.

Next, the operation and effects of the automatic steering device 1 according to the present embodiment configured as described above will be described.
Normally, the automatic steering microcomputer 30 executes the automatic steering control using the position control unit 51, the speed control unit 53, and the current control unit 55, which are the first constituent means, when the condition for determining the state of the vehicle is normal. However, when a disturbance such as vibration acts on the vehicle and the condition for determining the state of the vehicle becomes abnormal, the microcomputer 30 for automatic steering changes the current control unit 55, which is the third component, from the first component to the vehicle. Switch to vibration suppression control. Then, when the vehicle vibration and the like are removed by the third constituent means and the condition for determining the state of the vehicle becomes normal, the process returns to the first constituent means in order to execute the automatic steering control.

  However, at this time, if the absolute value of the difference between the automatic steering command steering angle θs *, which is the command state quantity, and the actual steering angle θs is equal to or greater than the predetermined steering angle 1 (θs0), the rapid rotation of the steering wheel is stopped. This is dangerous because it may occur. Therefore, before returning to the first constituent means for executing the automatic steering control, the EPS microcomputer 50 determines in the speed control execution determining section 65 the automatic steering command steering angle θs *, which is the command state quantity, and the actual steering angle θs. It is determined whether or not the absolute value of the difference is equal to or greater than a predetermined steering angle 1 (θs0).

  When the absolute value of the difference between the automatic steering command steering angle θs *, which is the command state quantity, and the actual steering angle θs is smaller than the predetermined steering angle 1 (θs0), the EPS microcomputer 50 performs the automatic steering control. The process returns to the first component to be executed, and the automatic steering control is continued. On the other hand, when it is determined that the absolute value of the difference between the automatic steering command steering angle θs * and the actual steering angle θs is equal to or greater than the predetermined steering angle 1 (θs0), the speed control unit 53 as the second component means; The current control unit 55 is configured to execute the steering deviation suppression control.

  That is, when the vehicle state quantity is normal, the position control unit 51, the speed control unit 53, and the position control unit 51 that use the automatic steering command steering angle θs * of the actuator 20 of the steering mechanism as the original automatic steering device 1 as the command state quantity The automatic steering control is executed by the first constituent means including the current control unit 55. When the yaw rate γ, which is the vehicle state quantity, detects an abnormal vibration state of the vehicle, the position control unit 51 and the speed control unit 53 are disconnected from the first constituent means, and the automatic steering command steering angle θs * , The vehicle vibration suppression control is executed by a third component comprising a current control unit 55 that uses the automatic steering command motor current data Ir1 * as the command state quantity.

  Further, when the yaw rate γ, which is the vehicle state quantity, becomes normal after the vehicle vibration suppression control is executed by the third constituent means, the automatic steering command steering angle θs *, which is the command state quantity, becomes It is determined whether or not the absolute value of the difference between the steering angles θs is equal to or greater than a predetermined steering angle 1 (θs0).

  If the absolute value of the difference between the automatic steering command steering angle θs * and the actual steering angle θs is equal to or larger than the predetermined steering angle 1 (θs0), the steering wheel may suddenly rotate. The control is not performed by the first component that sets the command steering angle θs * as the command state quantity. That is, by selecting the speed control unit 53 and the current control unit 55, which are the second components, the motor speed, that is, the amount of change in the motor position is controlled, thereby suppressing a rapid change in the position deviation. This suppresses sudden rotation of the steering wheel caused by the difference between the automatic steering command steering angle θs * and the actual steering angle θs.

  In the automatic steering command motor rotation speed data ωr1 *, the speed limit value is selected according to the vehicle speed SP. For example, when the vehicle speed SP is high, the speed limit value is made smaller. Further, sudden rotation of the steering wheel can be suppressed.

In addition, this embodiment may be changed as follows.
In the present embodiment, when the yaw rate γ is in an abnormal state, the automatic steering device 1 switches the control system from the first configuration unit to the control system controlled by the third configuration unit. The control system may be switched by a detector capable of detecting a change in behavior.

In the present embodiment, the control system is switched immediately when the yaw rate γ becomes abnormal, but the control system is switched after a predetermined time has elapsed from the time when the yaw rate γ becomes abnormal. Is also good.

In this embodiment, it is assumed that the automatic steering command motor rotation speed data ωr1 * is generated by adding a speed limit value based on the vehicle speed SP calculated from the speed limit value / vehicle speed map (not shown). However, the configuration is not limited to this, and a configuration may be adopted in which the speed control unit 53 has a speed limit value based on the vehicle speed SP calculated from a speed limit value / vehicle speed map (not shown) at a subsequent stage.

In the present embodiment, the present invention is embodied using two microcomputers, the microcomputer 50 for the EPS as the first control means and the microcomputer 30 for the automatic steering as the second control means. The control means and the second control means may be embodied by one microcomputer.

-In this embodiment, although the present invention was embodied in column assist EPS, the present invention may be applied to rack assist EPS and pinion assist EPS.

In the present embodiment, the present invention is embodied as a DC motor as the motor 21 that is the drive source of the EPS actuator 20, but the present invention may be a three-phase brushless DC motor, an induction motor, and a stepping motor.

1: automatic steering device, 2: steering, 3: steering shaft,
4: Rack and pinion mechanism, 5: Rack shaft, 8: Column shaft,
9: intermediate shaft, 10: pinion shaft, 11: tie rod, 12: steered wheel, 20: actuator (steering force assist device),
21: motor, 22: motor rotation angle sensor, 23: reduction mechanism,
24: GPS, 25: vehicle speed sensor (vehicle speed detecting means), 26: steering angle sensor,
27: yaw rate sensor, 28: EPS ECU, 29: automatic steering ECU,
30: microcomputer for automatic steering (second control means),
31: command steering angle generator, 50: EPS microcomputer (first control means),
51: position control unit (P control), 52: automatic steering mode switching unit (speed control),
52a: automatic steering mode switching unit a contact, 52b: automatic steering mode switching unit b contact,
52c: automatic steering mode switching section c contact,
53: speed control unit (PID control), 54: automatic steering mode switching unit (current control),
54a: automatic steering mode switching unit a contact, 54b: automatic steering mode switching unit b contact,
54c: automatic steering mode switching section c contact,
55: current control unit (PID control), 56: PWM output unit, 57: drive circuit unit
58: Differentiator,
59: automatic steering command steering angle / auto steering command motor rotation angle data converter,
60: battery, 61: current sensor,
65: speed control execution determination unit (determination means), 66: speed command generation unit,
67: current control execution determination unit, 68: current command generation unit, 70: position subtractor,
71: speed subtractor, 72: current subtractor, 90: in-vehicle network (CAN),
SP: vehicle speed, θs *: automatic steering command steering angle, θs: actual steering angle,
Δθs *: The difference between the previous value and the current value of the automatic steering command steering angle,
Δθs * 0: predetermined command steering angle deviation 1,
θs0: predetermined steering angle 1, θs1: predetermined steering angle 2,
θcon: upper position information (GPS, car navigation, etc.), γ: yaw rate,
θr *: automatic steering command motor rotation angle, θr: actual motor rotation angle,
Δθr: motor rotation angle deviation value,
ωr1 *: Automatic steering command motor rotation speed data,
ωr0 *: command motor rotation speed data generated by the position control unit,
ωr *: final command motor rotation speed data, ωr: actual motor rotation speed,
Δωr: motor rotation speed deviation value,
Ir1 *: Automatic steering command motor current data,
Ir0 *: command motor current data generated by the speed control unit,
Ir *: last command motor current data, Ir: actual motor current,
ΔIr: motor current deviation value,
V *: Motor voltage command,
FLG1: automatic steering mode switching flag (automatic speed control),
FLG2: Automatic steering mode switching flag (automatic current control)

Claims (2)

Based on the command status amount input in every predetermined period, comprising a first control hand stage performs state quantity control of the motor of the steering mechanism,
The first control means includes:
A first configuration unit including a position control unit, a speed control unit, and a current control unit of an actuator of a steering mechanism including the motor;
A second component comprising a speed controller and a current controller of an actuator of the steering mechanism;
A third control unit configured by a current control unit of an actuator of the steering mechanism;
The first control means is configured to perform the first control means and the second control means as the state quantity control in accordance with whether the vehicle is in a straight traveling state and a change in the state of the vehicle in the presence or absence of vehicle vibration. Or selecting the third constituent means,
In the automatic steering device that generates a command state quantity that is input every predetermined cycle,
An automatic steering command steering angle is the command state quantity, the absolute value of the difference between the actual steering angle is further provided with a determination hand stage determines whether or not a predetermined steering angle or more,
The first control means selects the third constituent means from the first constituent means in accordance with a change in the state of the vehicle , and then changes the first structure in response to a change in the state of the vehicle. When selecting the means, while the determination means determines that the absolute value of the difference between the automatic steering command steering angle and the actual steering angle is equal to or greater than the predetermined steering angle, the second configuration means To choose,
An automatic steering device characterized by the following. Further provided is a vehicle speed detecting means for detecting a vehicle speed,
The first control unit determines that the absolute value of the difference between the automatic steering command steering angle and the actual steering angle is equal to or greater than the predetermined steering angle, and as a result, the second configuration unit is selected. In this case, a speed limit value for limiting the speed of the speed control unit in order to suppress an abrupt change in the amount of change in the state quantity control of the motor is determined, and a relationship between the speed limit value and the vehicle speed is determined. The automatic steering device according to claim 1, wherein the automatic steering device is determined based on the map.

Images