JP2016016735A - Automatic steering system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constitute an automatic steering system, safely transferrable to manual steering from automatic steering even when required state data is not acquired for executing the automatic steering.SOLUTION: A microcomputer 30 comprises an expected command steering angle correction arithmetic operation part 56 for executing automatic steering based on a command steering angle θp* of first sampling when an abnormality determination part 40 determines that the command steering angle θp* sampled with every predetermined period and an actual vehicle speed V are normal and correcting an expected command steering angle θp*(k) on and after a second sample stored by an expected command steering angle storage part 54 based on an expected vehicle speed V(k) stored in an expected vehicle speed storage part 42 and the sampled actual vehicle speed V when the abnormality determination part 40 determines that the command steering angle θp* sampled with every predetermined period is abnormal and the sampled actual vehicle speed V is normal, and is constituted for executing the automatic steering based on an expected command steering angle corrected by the expected command steering angle correction arithmetic operation part 56.SELECTED DRAWING: Figure 6

Description

  The present invention relates to an automatic steering apparatus.

  2. Description of the Related Art Conventionally, in an automatic steering apparatus that performs steering by controlling rotation of a steering motor, when a driver performs manual steering during automatic steering, the automatic steering mode is generally switched to the manual steering mode. .

  For example, in the automatic steering device described in Patent Document 1, when switching from automatic driving to manual driving by the driver, the operation sharing ratio at the time of transition is smoothed with a time margin according to the external environment. Transition control is performed.

Japanese Patent Laid-Open No. 10-309961

  However, in the above method, there is no description of how to deal with the case where the situation data necessary for performing the automatic steering is not obtained, that is, when the automatic driving is stopped at a timing not predicted by the driver. There was a problem.

  An object of the present invention is to provide an automatic steering apparatus that can safely shift from automatic steering to manual steering even when situation data necessary for performing automatic steering is not obtained.

  In order to solve the above-described problems, the invention according to claim 1 is directed to an actual vehicle speed for detecting an actual vehicle speed in an automatic steering device that performs a steering angle control of a steering mechanism based on a command steering angle input every predetermined period. Detecting means; scheduled command steering angle detecting means for detecting at least two samples of a scheduled command steering angle that is a steering angle after the second sampling ring sampled simultaneously with the predetermined period of the command steering angle; and the scheduled command steering A schedule command steering angle storage means for storing the schedule command steering angle detected by the angle detection means; and a schedule vehicle speed which is a vehicle speed after the second sampling sampled simultaneously with the predetermined cycle of the actual vehicle speed. Planned vehicle speed detecting means for detecting the same number of samples as the steering angle; planned vehicle speed storing means for storing the planned vehicle speed detected by the planned vehicle speed detecting means; An abnormality determination unit that determines whether the command steering angle and the actual vehicle speed are normal or abnormal, and a control unit that performs a steering angle control of the steering mechanism based on the command steering angle, the control unit includes: When the abnormality determination means determines that the command steering angle and the actual vehicle speed sampled every predetermined cycle are normal, automatic steering is executed based on the command steering angle at the first sampling, while the abnormality When the determination means determines that the command steering angle sampled every predetermined period is abnormal and the sampled actual vehicle speed is normal, the planned vehicle speed and the sampling stored in the planned vehicle speed storage means A scheduled command steering angle correction unit that corrects the scheduled command steering angle of the second and subsequent samples stored in the scheduled command steering angle storage unit based on the actual vehicle speed, Serial schedule instructed by the steering angle correction means performing the automatic steering based on the scheduled command steering angle is corrected, and the gist.

  In the automatic steering device according to the present invention, the actual vehicle speed detecting means for detecting the actual vehicle speed and the scheduled command steering angle, which is the steering angle after the second sampling ring sampled simultaneously with the predetermined cycle of the command steering angle, are at least two samples or more. Schedule command steering angle detection means for detecting, schedule command steering angle storage means for storing the schedule command steering angle detected by the schedule command steering angle detection means, and the second and subsequent samplings sampled simultaneously with a predetermined cycle of the actual vehicle speed The planned vehicle speed detection means for detecting the same number of samples as the planned command steering angle, the planned vehicle speed storage means for storing the planned vehicle speed detected by the planned vehicle speed detection means, the command steering angle and the actual vehicle speed are normal An abnormality determination unit that determines whether the vehicle is abnormal or a control unit that performs steering angle control of the steering mechanism based on the command steering angle. When the means determines that the command steering angle and the actual vehicle speed sampled at a predetermined cycle are normal, automatic steering is executed based on the command steering angle at the first sampling, while the abnormality determination means samples at a predetermined cycle. If it is determined that the commanded steering angle is abnormal and the sampled actual vehicle speed is normal, the scheduled command steering angle storage means is based on the planned vehicle speed stored in the planned vehicle speed storage means and the sampled actual vehicle speed. And a scheduled command steering angle correction unit that corrects the scheduled command steering angle for the second and subsequent samples stored in the step, and performs automatic steering based on the scheduled command steering angle corrected by the scheduled command steering angle correction unit; did.

  That is, the scheduled command steering angle detection means for detecting at least two samples or more of the scheduled command steering angle, which is the steering angle after the second sample ring sampled simultaneously with the predetermined cycle of the command steering angle, and the scheduled command steering angle detection means. The scheduled command steering angle storage means for storing the scheduled command steering angle, and the scheduled vehicle speed, which is the vehicle speed after the second sampling that is sampled simultaneously with the predetermined cycle of the actual vehicle speed, to detect the same number of samples as the scheduled command steering angle When the abnormality determination means that includes vehicle speed detection means and determines whether the command steering angle and the actual vehicle speed are normal or abnormal determines that the command steering angle and the actual vehicle speed sampled every predetermined cycle is normal, the first sampling The automatic steering is executed based on the command steering angle. As a result, since automatic steering can be executed with the latest command steering angle, a safe and accurate automatic steering device is obtained.

  On the other hand, when the command determining angle sampled at every predetermined cycle is abnormal and the sampled actual vehicle speed is determined to be normal by the abnormality determining unit, the planned vehicle speed and the sampled actual vehicle stored in the planned vehicle speed storage unit are determined. The scheduled command steering angle correction means for correcting the scheduled command steering angle after the second sample stored in the scheduled command steering angle storage means based on the speed, and the scheduled command steering corrected by the scheduled command steering angle correction means. Performs automatic steering based on the angle. As a result, since automatic steering can be executed with a reliable scheduled command steering angle, a safe automatic steering device can be constructed.

  According to the present invention, it is possible to provide an automatic steering device that can safely shift from automatic steering to manual steering even when situation data necessary for performing automatic steering is not obtained.

The schematic block diagram of the automatic steering apparatus in this embodiment. The control block diagram of the automatic steering device in this embodiment. The control block diagram of the command steering angle process part of the automatic steering in this embodiment. The control block diagram of the command steering angle correction | amendment part of the automatic steering in this embodiment. The flowchart figure which shows the process sequence of the command steering angle process part of the automatic steering in this embodiment. The flowchart figure which shows the process sequence of the instruction | command steering angle correction | amendment part of the automatic steering in this embodiment. The flowchart figure which shows the process sequence of the plan travel distance calculating part in this embodiment. Explanatory drawing of command steering angle (theta) p *, actual vehicle speed V, planned command steering angle (theta) p * (k), and planned vehicle speed V (k) in this embodiment.

Hereinafter, an embodiment of the present invention embodied in an automatic steering apparatus 1 having a column-type electric power steering apparatus (hereinafter referred to as EPS) will be described with reference to the drawings.
As shown in FIG. 1, the automatic steering device 1 of this embodiment that performs steering angle control of a steering mechanism based on a command steering angle θp * input at every predetermined cycle is configured so that the command steering angle input at every predetermined cycle. An automatic steering ECU 28, which is a host controller, transmits θp * and the actual vehicle speed V detected from the vehicle speed sensor 25, which is an actual vehicle speed detection means, to the EPS ECU 29 via the in-vehicle network 70 (CAN).

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

  The EPS also includes an EPS actuator 24 as a steering force assisting device that applies an assist force for assisting a steering operation to the steering system using the motor 21 as a drive source, and an EPS ECU 29 that controls the operation of the EPS actuator 24. Yes.

  The EPS actuator 24 of the present embodiment is a column type EPS actuator, and the motor 21 that is a drive source thereof is drivingly connected to the column shaft 8 via a speed reduction mechanism 23. The rotation of the motor 21 is decelerated by the speed 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.

  On the other hand, a torque sensor 26 and a steering angle sensor 27 are connected to the EPS ECU 29, and the EPS ECU 29 detects the steering torque τ and the actual steering angle θp based on the output signals of these sensors.

  The torque sensor 26 is a twin resolver type torque sensor. The EPS ECU 29 calculates a steering torque τ based on output signals of a pair of resolvers provided at both ends of a torsion bar (not shown). Further, the EPS ECU 29 calculates a target assist force based on each detected state quantity, and assists the operation of the EPS actuator 24, that is, an assist given to the steering system through the supply of drive power to the motor 21 that is the drive source. Control the power.

Next, the electrical configuration of the automatic steering apparatus 1 according to this embodiment will be described.
FIG. 2 is a control block diagram of the automatic steering device 1 of the present embodiment. As shown in the figure
The EPS ECU 29 supplies drive power to the microcomputer 30 that is a control unit that performs steering angle control of the steering mechanism based on the command steering angle θp * and to the motor 21 that is the drive source of the EPS actuator 24 based on the motor control signal. A drive circuit unit 31 to be supplied and a current sensor 32 for detecting a motor actual current Im supplied to the motor 21 are provided.

  The drive circuit unit 31 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 microcomputer 30 defines the on-duty ratio of each switching element that constitutes the drive circuit unit 31. 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, thereby generating motor driving power based on the power supply voltage of the battery 20, and the motor 21. It is configured to output to.

  The microcomputer 30 outputs a motor control signal to the drive circuit unit 31 based on the motor actual current Im, the steering torque τ, the actual vehicle speed V, and the actual steering angle θp detected based on the output signal of each sensor. .

  Each control block shown below is realized by a computer program executed by the microcomputer 30. The microcomputer 30 detects each state quantity at a predetermined sampling period, and generates a motor control signal by executing each arithmetic processing shown in the following control blocks at every predetermined period.

  As shown in FIG. 2, the microcomputer 30 includes an automatic steering command steering angle processing unit 33, an automatic steering switching unit 34, and a motor control signal generation unit 35 that generates a motor control signal for controlling the drive circuit unit 31. ing.

The automatic steering command steering angle processing unit 33 will be described with reference to the control block diagram of the automatic steering command steering angle processing unit 33 in this embodiment shown in FIG.
The automatic steering command steering angle processing unit 33 determines whether the signals (command steering angle θp * and actual vehicle speed V) transmitted from the automatic steering ECU 28 via the in-vehicle network 70 (CAN) are normal or abnormal. An abnormality determination unit 40 that is a means, a planned vehicle speed V (2) to V (n0) processing unit 41 that is a planned vehicle speed detection unit that detects the planned vehicle speed V (k) transmitted from the automatic steering ECU 28, and a planned vehicle speed. Has a planned vehicle speed storage unit 42 which is a planned vehicle speed storage means.

  Further, the command steering angle processing unit 33 for automatic steering subtracts the command steering angle correction unit 43 for correcting the command steering angle, the command steering angle θp * output from the command steering angle correction unit 43, and the actual steering angle θp. A subtractor 45 is provided. Then, the subtracter 45 subtracts the actual steering angle θp from the command steering angle θp * to generate a steering angle deviation Δθp. Based on the generated steering angle deviation Δθp, the position control unit (PID control) 44 generates a motor current command Im1 * during automatic steering.

Here, the command steering angle θp *, the actual vehicle speed V, the planned command steering angle θp * (k), and the planned vehicle speed V (k) will be described with reference to FIG.
When the communication from the automatic steering ECU 28 is normal, the EPS ECU 29 captures the command steering angle θp * and the actual vehicle speed V at a predetermined cycle at the point P1. In the present embodiment, the EPS ECU 29 further includes the planned command steering angle θp * (2) and the planned vehicle speed V (2) at the point P2 calculated by the automatic steering ECU 28, the planned command steering angle θp * (3) at the point P3, and The planned vehicle speed V (3), the planned command steering angle θp * (n0) and the planned vehicle speed V (n0) at the point Pn0 are fetched and stored in the respective storage units.

  The EPS ECU 29 performs automatic steering at the command steering angle θp * and the actual vehicle speed V that are fetched at a predetermined cycle when the automatic steering ECU 28 is normal. On the other hand, when the automatic steering ECU 28 is abnormal (in this embodiment, an abnormality occurs at a point between the points P1 and P2), the EPS ECU 29 determines the planned command steering angle θp * (k) stored in the storage unit and the planned value. The planned command steering angle θp * (k) is corrected using the vehicle speed V (k), and automatic steering is executed.

  Next, the abnormality determination unit 40 inputs the command steering angle θp * and the actual vehicle speed V, and when the command steering angle θp * is abnormal, sets the command steering angle abnormality flag FLGpa (FLGpa ← “1”). . When the actual vehicle speed V is abnormal, the actual vehicle speed abnormality flag FLGva is set (FLGva ← “1”).

  The planned vehicle speed V (2) to V (n0) processing unit 41 detects at least two samples of the planned vehicle speed V (k) that is the vehicle speed after the second sampling that is sampled simultaneously with the predetermined cycle of the actual vehicle speed V. The planned vehicle speed V (k) detected at least two samples or more is stored in the planned vehicle speed storage unit 42 which is a planned vehicle speed storage means.

  When the abnormality determination unit 40 determines that the command steering angle θp * is normal, the command steering angle correction unit 43 outputs the command steering angle θp * sampled at a predetermined period to the subtractor 45 and also performs an abnormality. When the determination unit 40 determines that the command steering angle θp * is abnormal, the scheduled command steering angle θp * (k for two or more samples after the second sampling that is sampled simultaneously with the predetermined period of the command steering angle. ) Is output to the subtracter 45 as the command steering angle θp *. The details of the command steering angle correction unit 43 will be described later.

The command steering angle correction unit 43 will be described with reference to a control block diagram of the command steering angle correction unit 43 for automatic steering in the present embodiment in FIG.
The command steering angle correction unit 43 includes a command steering angle θp *, a planned command steering angle θp * (k), an actual vehicle speed V, a planned vehicle speed V (k), a command steering angle abnormality flag FLGpa, and an actual vehicle speed abnormality flag FLGva. Entered.

  The command steering angle correction unit 43 has a planned travel distance calculation unit 50 that calculates the planned travel distance from the planned vehicle speed V (k) and the actual vehicle speed abnormality flag FLGva, and a planned travel distance storage that stores the planned travel distance xa (m). Part 51. Further, the command steering angle correction unit 43 calculates the sampling time point from the actual vehicle speed V, the estimated travel distance xb after the command steering angle abnormality, and the planned travel distance xa (m) stored in the planned travel distance storage unit 51. A mileage estimation and sampling time point calculation unit 52 after command steering angle abnormality is included.

  Further, the command steering angle correction unit 43 processes the planned command steering angle θp * (n0) from the planned command steering angle θp * (2), which is a planned command steering angle detection means for detecting the planned command steering angle θp * (k). And a scheduled command steering angle storage unit 54 that is a scheduled command steering angle storage unit that stores the scheduled command steering angle θp * (k).

Further, the command steering angle correction unit 43 is scheduled to be interpolated by the formula (1) from the planned travel distance xa (m), the estimated travel distance xb after the command steering angle abnormality and the planned command steering angle θp * (k). A command steering angle interpolation calculation unit 55 is provided.
θp * (k) = θp * (k−1) + (θp * (k) −θp * (k−1)) * (xb−xa (k−1)) / (xa (k) −xa (k -1)) ... (1) Formula

Further, the command steering angle correcting unit 43 is a scheduled command steering angle correcting unit that corrects the scheduled command steering angle θp * (k) interpolated by the scheduled command steering angle interpolation calculating unit 55 using the equation (2). An angle correction calculation unit 56 is provided.
θp * (k) = θp * (k) × (f (V) / f (V (k))) (2)

  The command steering angle correction unit 43 includes a command steering angle switching unit 58 that switches the command steering angle θp * or the scheduled command steering angle θp * (k) with the command steering angle abnormality flag FLGpa. That is, when the command steering angle abnormality flag FLGpa is in the reset state, the command steering angle switching unit 58 connects the command steering angle switching unit contacts 58a and 58c and outputs the command steering angle θp *. On the other hand, when the command steering angle abnormality flag FLGpa is in the set state, the command steering angle switching unit 58 connects the command steering angle switching unit contacts 58b and 58c and outputs the planned command steering angle θp * (k).

  Next, the automatic steering switching unit 34 includes a torque / motor current command value map 60, a motor command current switching unit 61, and a manual steering intervention determination unit 62. The torque / motor current command value map 60 receives the steering torque τ and the actual vehicle speed V as inputs, and generates a manual steering intervention motor current command Im2 *. The torque / motor current command value map 60 is configured to determine a larger manual steering intervention motor current command Im2 * as the actual vehicle speed V is smaller for the same steering torque τ.

  The manual steering intervention determination unit 62 determines whether or not the driver has performed manual steering intervention during automatic steering. That is, when a steering torque τ greater than a predetermined value is detected for a predetermined time or more, it is determined that the driver has made a manual steering intervention during automatic steering, a manual steering intervention flag FLGma is set, and a motor command current switching unit is set. To 61.

The motor command current switching unit 61 switches between the automatic steering motor current command Im1 * and the manual steering intervention motor current command Im2 * based on the determination of the manual steering intervention determination unit 62.
That is, when the manual steering intervention determination unit 62 determines that manual steering intervention is not performed, the manual steering intervention flag FLGma is reset, and the motor command current switching unit contacts 61a and 61c are connected. Then, the motor current command Im1 * during automatic steering is output as the motor current command Im *.

On the other hand, when the manual steering intervention determination unit 62 determines that manual steering intervention is performed, the manual steering intervention flag FLGma is set, and the motor command current switching unit contacts 61b and 61c are connected.
Then, the motor current command Im2 * at the time of manual steering intervention is output as the motor current command Im *.

  The motor control signal generation unit 35 includes a subtractor 65 that subtracts the motor actual current Im from the motor current command Im *, a motor current control unit 63 that performs PID control on the motor current deviation ΔIm that is the output of the subtractor 65, and a motor current. The motor voltage command V * that is the output of the control unit 63 is converted into a motor control signal, and the PWM output unit 64 is output to the drive circuit unit 31.

Next, the processing procedure of the command steering angle processing unit 33 for automatic steering by the microcomputer 30 in this embodiment will be described with reference to FIG.
First, the microcomputer 30 determines whether various signals (command steering angle θp *, actual vehicle speed V) from the automatic steering ECU 28 are normal (step S101). When the microcomputer 30 determines that various signals (command steering angle θp *, actual vehicle speed V) from the automatic steering ECU 28 are normal (step S101: YES), the microcomputer 30 stores the planned command steering angle and the planned vehicle speed data. “1” is set to the counter k (step S102).

  Then, the microcomputer 30 reads the command steering angle θp * (step S103). Next, the microcomputer 30 reads (n0-1) planned command steering angles θp * (k) and (n0-1) planned vehicle speeds V (k) from the automatic steering ECU 28, and stores the planned command steering angles. Is stored in the unit 54 and the planned vehicle speed storage unit 42 (step S104). Then, the microcomputer 30 performs automatic steering based on the command steering angle θp * (step S105).

  Next, the microcomputer 30 determines whether manual steering has intervened (step S106). When the microcomputer 30 determines that manual steering is not intervening (step S106: NO), the microcomputer 30 proceeds to step S101. On the other hand, when the microcomputer 30 determines that manual steering is intervening (step S106: YES), the microcomputer 30 stops automatic steering (step S107).

  Then, the microcomputer 30 switches the motor command current switching unit 61, connects the motor command current switching unit contacts 61b and 61c (step S108), executes manual steering (step S109), and ends the process. Here, the method for determining whether or not manual steering has intervened can be processed, for example, when the steering torque τ becomes equal to or greater than a predetermined steering torque τ0.

  On the other hand, when the microcomputer 30 determines that various signals (command steering angle θp *, actual vehicle speed V) from the automatic steering ECU 28 are not normal (step S101: NO), the microcomputer 30 switches the command steering angle switching unit 58, Command steering angle switching unit contacts 58b and 58c are connected (step S110).

  Next, the microcomputer 30 calculates the planned travel distance xa (m) by integrating the planned vehicle speed V (m) (step S111). The planned travel distance calculation method will be described later. Next, the microcomputer 30 determines whether or not the actual vehicle speed V is normal (step S112). If the microcomputer 30 determines that the actual vehicle speed V is not normal (step S112: NO), the microcomputer 30 increments the scheduled command steering angle and the counter k of the scheduled vehicle speed data (step S113).

  Next, the microcomputer 30 reads the scheduled command steering angle θp * (k) from the scheduled command steering angle storage unit 54 (step S114). Then, the microcomputer 30 performs automatic steering based on the scheduled command steering angle θp * (k) read from the scheduled command steering angle storage unit 54 (step S115).

Next, the microcomputer 30 determines whether manual steering has intervened (step S116).
When the microcomputer 30 determines that manual steering is not intervening (step S116: NO), the microcomputer 30 has normal signals (command steering angle θp *, actual vehicle speed V) from the automatic steering ECU 28. It is determined whether or not (step S117). On the other hand, if the microcomputer 30 determines that manual steering is intervening (step S116: YES), the microcomputer 30 proceeds to step S107.

  Next, if the microcomputer 30 determines that various signals (command steering angle θp *, actual vehicle speed V) from the automatic steering ECU 28 are not normal (step S117: NO), the microcomputer 30 stores the planned command steering angle and the planned vehicle speed data. It is determined whether or not the counter k is larger than a predetermined scheduled command steering angle and a planned vehicle speed data number n0 transferred from the automatic steering ECU (step S118).

  On the other hand, when the microcomputer 30 determines that various signals (command steering angle θp *, actual vehicle speed V) from the automatic steering ECU 28 are normal (step S117: YES), the command steering angle switching unit 58 is switched. The command steering angle switching unit contacts 58a and 58c are connected (step S119), and the process proceeds to step S102.

  If the counter k of the planned command steering angle and the planned vehicle speed data is larger than the predetermined planned command steering angle and the planned vehicle speed data number n0 transferred from the automatic steering ECU (step S118: YES), the microcomputer 30 performs step The process proceeds to S107.

  On the other hand, if the counter k of the planned command steering angle and the planned vehicle speed data is less than the predetermined planned command steering angle and planned vehicle speed data number n0 transferred from the automatic steering ECU (step S118: NO), The process proceeds to S112.

  Next, when the microcomputer 30 determines that the actual vehicle speed V is normal (step S112: YES), the microcomputer 30 reads the actual vehicle speed V (step S120). Then, the microcomputer 30 estimates the estimated travel distance xb after the command steering angle abnormality (step S121).

  Next, the microcomputer 30 estimates the estimated travel distance xb after the command steering angle abnormality from the planned travel distance xa (m), and selects the sampling time “j” (step S122). A method for calculating the planned travel distance xa (k) will be described later.

Next, the microcomputer 30 reads data of the scheduled command steering angle θp * (j−1) and the scheduled command steering angle θp * (j) from the scheduled command steering angle storage unit 54 (step S123).
Then, the microcomputer 30 sets j to the counter k of the planned command steering angle and the planned vehicle speed data (step S124).

  Next, the microcomputer 30 performs an interpolation calculation of the scheduled command steering angle θp * based on the equation (1) (step S125). Further, the microcomputer 30 corrects the planned command steering angle θp * based on the function of the actual vehicle speed and the planned vehicle speed described in the equation (2) (step S126). Then, the microcomputer 30 performs automatic steering based on the corrected scheduled command steering angle θp * (step S127).

  Next, the microcomputer 30 determines whether manual steering has intervened (step S128). If the microcomputer 30 determines that manual steering is not intervening (step S128: NO), the microcomputer 30 has normal signals (command steering angle θp *, actual vehicle speed V) from the automatic steering ECU 28. It is determined whether or not (step S129). On the other hand, if the microcomputer 30 determines that manual steering is intervening (step S128: YES), the microcomputer 30 proceeds to step S107.

  Next, when the microcomputer 30 determines that the various signals (command steering angle θp *, actual vehicle speed V) from the automatic steering ECU 28 are not normal (step S129: NO), the planned command steering angle and planned vehicle speed data are displayed. It is determined whether or not the counter k is larger than a predetermined scheduled command steering angle and a planned vehicle speed data number n0 transferred from the automatic steering ECU (step S130).

  On the other hand, when the microcomputer 30 determines that the various signals (command steering angle θp *, actual vehicle speed V) from the automatic steering ECU 28 are normal (step S129: YES), the microcomputer 30 switches the command steering angle switching unit 58. The command steering angle switching unit contacts 58a and 58c are connected (step S131), and the process proceeds to step S102.

  If the counter k of the planned command steering angle and the planned vehicle speed data is larger than the predetermined planned command steering angle and the planned vehicle speed data number n0 transferred from the automatic steering ECU (step S130: YES), the microcomputer 30 performs step The process proceeds to S107.

  On the other hand, when the counter k of the planned command steering angle and the planned vehicle speed data is less than the predetermined planned command steering angle and planned vehicle speed data number n0 transferred from the automatic steering ECU (step S130: NO), The process proceeds to S112.

Next, a processing procedure of the planned travel distance calculation unit 50 by the microcomputer 30 in the present embodiment will be described with reference to FIG.
First, the microcomputer 30 resets the values of the planned command steering angle and the counter m of the planned vehicle speed data and the planned travel distance xa (0) used in the planned travel distance calculation unit (step S201). Next, the microcomputer 30 increments the counter m of the planned command steering angle and the planned vehicle speed data (step S202).

  Then, the microcomputer 30 calculates the planned travel distance xa (m) by adding the planned vehicle speed V (m) to the planned travel distance xa (m−1) (step S203). Next, the microcomputer 30 stores the planned travel distance xa (m) in the planned travel distance storage unit 51 (step S204). Next, the microcomputer 30 determines whether or not the counter m of the planned command steering angle and the planned vehicle speed data is larger than a predetermined planned command steering angle and the planned vehicle speed data number n0 transferred from the automatic steering ECU (step S205). ).

  When the counter m of the planned command steering angle and the planned vehicle speed data is less than the predetermined planned command steering angle and the planned vehicle speed data number n0 transferred from the automatic steering ECU (step S205: NO), The process proceeds to step S202. On the other hand, when the counter m of the planned command steering angle and the planned vehicle speed data is larger than the predetermined planned command steering angle and the planned vehicle speed data number n0 transferred from the automatic steering ECU (step S205: YES), the microcomputer 30 Finish the process.

Next, the operation and effect of the automatic steering apparatus of the present embodiment configured as described above will be described.
The vehicle speed sensor 25 that detects the actual vehicle speed V and the scheduled command steering angle θp * (k) that is the steering angle after the second sample ring that is sampled simultaneously with the predetermined period of the command steering angle θp * is detected at least two samples. The scheduled command steering angle θp * (2) to the scheduled command steering angle θp * (n0) processing unit 53, the scheduled command steering angle storage unit 54 for storing the scheduled command steering angle θp * (k), and a predetermined actual vehicle speed V A planned vehicle speed V (2) to V (n0) processing unit for detecting the same number of samples as the planned command steering angle θp * (k), which is the vehicle speed after the second sampling that is sampled at the same time as the cycle. 41, a planned vehicle speed storage unit 42 that stores the planned vehicle speed V (k), an abnormality determination unit 40 that determines whether the command steering angle θp * and the actual vehicle speed V are normal, and an instruction steering angle θp *. , Steering angle of steering mechanism A microcomputer 30 that performs control. When the abnormality determination unit 40 determines that the command steering angle θp * and the actual vehicle speed V sampled at predetermined intervals are normal, the command steering at the first sampling is performed. While automatic steering is executed based on the angle θp *, when the abnormality determination unit 40 determines that the command steering angle θp * sampled every predetermined period is abnormal and the sampled actual vehicle speed V is normal, Based on the scheduled vehicle speed V (k) stored in the scheduled vehicle speed storage unit 42 and the sampled actual vehicle speed V, the scheduled command steering angle θp * (k for the second and subsequent samples stored in the scheduled command steering angle storage unit 54 is stored. ) Is corrected, and automatic steering is executed based on the scheduled command steering angle θp * (k) corrected by the scheduled command steering angle correction calculation unit 56.

  That is, the planned command steering angle θp * (2) for detecting at least two samples of the planned command steering angle θp * (k), which is the steering angle after the second sample ring that is sampled simultaneously with the predetermined cycle of the command steering angle θp *. To the scheduled command steering angle θp * (n0) processing unit 53, the scheduled command steering angle storage unit 54 that stores the scheduled command steering angle θp * (k), and two sampling rings that are sampled simultaneously with a predetermined cycle of the actual vehicle speed V A planned vehicle speed V (2) to V (n0) processing unit 41 for detecting the same number of samples as the planned vehicle speed V (k), which is the vehicle speed after the first vehicle, is provided, and the command steering angle θp * When the abnormality determination unit 40 that determines whether the actual vehicle speed V is normal or abnormal determines that the command steering angle θp * and the actual vehicle speed V sampled every predetermined cycle are normal, the command steering angle at the first sampling is used. θp * To perform an automatic steering based. As a result, since automatic steering can be executed with the latest command steering angle θp *, a safe and accurate automatic steering device is obtained.

  On the other hand, when the abnormality determination unit 40 determines that the command steering angle θp * sampled every predetermined period is abnormal and the sampled actual vehicle speed V is normal, the planned vehicle speed stored in the planned vehicle speed storage unit 42 is determined. Based on V (k) and the sampled actual vehicle speed V, a scheduled command steering angle correction calculation unit that corrects the scheduled command steering angle θp * (k) for the second and subsequent samples stored in the scheduled command steering angle storage unit 54. The automatic steering is executed based on the scheduled command steering angle θp * (k) corrected by the scheduled command steering angle correction calculation unit 56. As a result, since the automatic steering can be executed at the reliable scheduled command steering angle θp * (k), a safe automatic steering device can be constructed.

  As a result, it is possible to configure an automatic steering device that can safely shift from automatic steering to manual steering even when situation data necessary for automatic steering is not obtained.

In addition, you may change this embodiment as follows.
In the present embodiment, when the command steering angle θp * transferred from the automatic steering ECU 28 becomes abnormal, the command steering angle θp * for the second and subsequent samples stored in the scheduled command steering angle storage unit 54 is stored. Although the automatic steering is continued using the command steering angle θp * (n0) from (2), a warning that the command steering angle θp * is abnormal may be issued or displayed at that time.

In the present embodiment, both the position control unit 44 and the motor current control unit 63 are PID controlled, but both the position control unit 44 and the motor current control unit 63 may be PI controlled.

In the present embodiment, the present invention is embodied in the column assist EPS, but the present invention may be applied to a rack assist EPS or a 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 24. However, the present invention may be a three-phase brushless DC motor, an induction motor, and a stepping motor.

In the present embodiment, the actual vehicle speed V from the vehicle speed sensor 25 is converted into a CAN signal via the automatic steering ECU 28. However, the actual vehicle speed V may be sent directly from the vehicle speed sensor 25 to the CAN 70.

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: Steering wheel, 20: Battery, 21: Motor, 23: Deceleration mechanism,
24: EPS actuator, 25: Vehicle speed sensor (actual vehicle speed detection means),
26: Torque sensor, 27: Steering angle sensor, 28: Automatic steering ECU, 29: EPSECU,
30: Microcomputer (control means), 31: Drive circuit unit, 32: Current sensor,
33: Command steering angle processing unit for automatic steering, 34: Automatic steering switching unit,
35: Motor control signal generation unit, 40: Abnormality determination unit (abnormality determination means),
41: Planned vehicle speed V (2) to V (n0) processing unit (planned vehicle speed detection means),
42: Planned vehicle speed storage unit (planned vehicle speed storage means), 43: Command steering angle correction unit,
44: Position control unit (PID control), 45, 65: Subtractor,
50: Planned mileage calculation unit, 51: Planned mileage storage unit,
52: Travel distance estimation and sampling time calculation unit after command steering angle abnormality,
53: Scheduled command steering angle θp * (2) to scheduled command steering angle θp * (n0) processing unit (scheduled command steering angle detection means),
54: Schedule command steering angle storage unit (schedule command steering angle storage means),
55: Schedule command steering angle interpolation calculation unit,
56: Schedule command steering angle correction calculation unit (schedule command steering angle correction means),
58: Command steering angle switching unit, 58a, 58b, 58c: Command steering angle switching unit contact point,
60: Torque / motor current command value map, 61: Motor command current switching unit,
61a, 61b, 61c: motor command current switching unit contact, 62: manual steering intervention determination unit,
63: Motor current control unit (PID control), 64: PWM output unit,
70: In-vehicle network (CAN),
V: actual vehicle speed, τ: steering torque,
Im1 *: motor current command during automatic steering, Im2 *: motor current command during manual steering intervention,
Im *: motor current command, Im: actual motor current, ΔIm: motor current deviation,
V *: motor voltage command, θp *: command steering angle, θp * (k): scheduled command steering angle,
θp: actual steering angle, Δθp: steering angle deviation,
V (k): Planned vehicle speed, V (m): Planned vehicle speed (used in the planned mileage calculation unit),
xa (m): planned travel distance, xb: estimated travel distance after command steering angle abnormality,
k: Counter of planned command steering angle and planned vehicle speed data,
m: Counter of planned command steering angle and planned vehicle speed data (used in planned mileage calculation unit),
n0: predetermined scheduled command steering angle and planned vehicle speed data number transferred from the automatic steering ECU,
FLGpa: Command steering angle abnormality flag (abnormal in flag set),
FLGva: Actual vehicle speed abnormality flag (abnormal in flag set),
FLGma: Manual steering intervention flag (manual steering intervention with flag set)

Claims (1)

In an automatic steering device that performs steering angle control of a steering mechanism based on a command steering angle that is input every predetermined cycle,
An actual vehicle speed detecting means for detecting the actual vehicle speed;
A scheduled command steering angle detection means for detecting at least two samples of a scheduled command steering angle that is a steering angle after the second sample ring that is sampled simultaneously with the predetermined period of the command steering angle;
Schedule command steering angle storage means for storing the schedule command steering angle detected by the schedule command steering angle detection means;
A planned vehicle speed detecting means for detecting a planned vehicle speed that is a vehicle speed after the second sampling sampled simultaneously with the predetermined cycle of the actual vehicle speed, and detecting the same number of samples as the planned command steering angle;
Planned vehicle speed storage means for storing the planned vehicle speed detected by the planned vehicle speed detection means;
An abnormality determining means for determining whether the command steering angle and the actual vehicle speed are normal or abnormal;
Control means for performing steering angle control of the steering mechanism based on the command steering angle,
The control means performs automatic steering based on the command steering angle at the first sampling when the abnormality determination means determines that the command steering angle and the actual vehicle speed sampled every predetermined cycle are normal. On the other hand, when the abnormality determining means determines that the command steering angle sampled at each predetermined cycle is abnormal and the sampled actual vehicle speed is normal, the stored stored in the planned vehicle speed storage means Based on the scheduled vehicle speed and the sampled actual vehicle speed, the scheduled command steering angle correcting means for correcting the scheduled command steering angle after the second sample stored in the scheduled command steering angle storage means is provided, and the scheduled command steering is performed. Performing automatic steering based on the scheduled command steering angle corrected by the angle correction means;
An automatic steering device characterized by this.

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