JP5586750B1 - Steering reaction force control device and steering reaction force control method - Google Patents

Abstract

In a steering reaction force control device applied to a steer-by-wire type vehicle, a feeling of discomfort with a feeling during steering of a steering wheel is reduced.
In a steer-by-wire type steering reaction force control device, the steering torque in the left and right steering is increased and the friction torque on the reaction force side in the left and right steering is accurately estimated from the half value of the difference in steering torque in the left and right steering By providing the steering friction torque estimating means (23, 24), it is possible to control the feeling of the steering wheel operation equally on the left and right, and to reduce the driver's uncomfortable feeling.
[Selection] Figure 2

Description

  The present invention relates to a steering reaction force control device and a steering reaction force control method for a vehicle including a steer-by-wire steering device.

  The friction torque of the steering mechanism in which the tire and the steering wheel (handle) are mechanically connected is estimated and calculated from the reaction torque generated on the steering shaft based on the steering torque of the driver, the torque of the assist motor, and the inertia of the steering system, There is a technique of using an estimation calculation result for control of electric power steering (see, for example, Patent Document 1).

  A so-called steer-by-wire steering device in which a tire and a steering wheel (handle) are mechanically separated has an advantage of not transmitting uncomfortable components such as vibration to a driver. For this reason, in recent years, interest in such a steer-by-wire type steering apparatus has increased. This steer-by-wire type steering device applies a force in a direction opposite to the direction in which the steering wheel is turned according to the steering actuator and the steering angle according to the steering wheel angle and the tire condition, according to the steering wheel steering amount. A reaction force actuator is provided.

  Such a steer-by-wire type steering device also has a friction torque related to the mechanical system. On the steered side (tire side), this friction can affect the steered response. On the reaction force side (handle side), the friction torque tends to be small because the mechanism is shorter than the conventional steering mechanism. For this reason, a feeling of friction may be intentionally given by reaction force control.

Japanese Patent No. 440489

However, the prior art has the following problems.
The friction torque related to the steering mechanism system may be different between left and right steering. On the reaction force side, if there is a difference in friction torque between the left and right, the feeling of steering wheel operation differs between the left and right, which may give the driver a feeling of strangeness with respect to the vehicle behavior.

  The prior art described in Patent Document 1 is a method for estimating and calculating the friction torque of a mechanically connected steering mechanism. Therefore, there is a problem that this technique cannot be applied as it is to a steer-by-wire steering device in which a tire and a steering wheel (handle) are mechanically separated.

  The present invention has been made to solve the above-described problems, and in a steer-by-wire type steering device, a steering reaction force control device and a steering reaction force that can reduce a sense of incongruity during steering of a steering wheel. The purpose is to obtain a control method.

  A steering reaction force control apparatus according to the present invention is a steering reaction force control apparatus applied to a steer-by-wire type vehicle in which an automobile handle and a tire are mechanically separated from each other. The steering torque when passing through the positive predetermined steering angle while the steering state is increasing and the steering torque when passing through the positive predetermined steering angle while the steering state is being switched back to the positive value. Positive steering friction torque estimation means for estimating the steering friction torque, steering torque when the steering wheel angle is negative and the predetermined steering angle is passed while the steering state is increasing, and the steering state is being switched back Negative steering friction torque estimating means for estimating a value half of the difference from the steering torque when passing through a predetermined negative steering angle as negative steering friction torque, and positive steering friction estimated by the positive steering friction torque estimating means G And a reaction force torque applying means for calculating a reaction force torque so that the steering response in left and right steering is equal to the left and right based on the negative steering friction torque estimated by the negative steering friction torque estimating means. It is to be prepared.

  The steering reaction force control method according to the present invention is a steering reaction force control method applied to a steer-by-wire type vehicle in which an automobile handle and a tire are mechanically separated from each other. Half of the difference between the steering torque when passing the positive predetermined steering angle while the steering state is increasing and the steering torque when passing the positive predetermined steering angle while the steering state is switching back Is the positive steering friction torque estimation step, and the steering torque when the steering angle is passed while the steering angle is increased while the steering angle is negative, and the steering state is Estimate calculation in the negative steering friction torque estimation step and the positive steering friction torque estimation step that estimate half the difference from the steering torque when passing through the negative steering angle during return as the negative steering friction torque Reaction force for calculating the reaction force torque so that the left and right steering response is equal to the left and right based on the calculated positive steering friction torque and the negative steering friction torque estimated and calculated in the negative steering friction torque estimation step. A torque applying step.

  According to the present invention, the friction torque in the left-right steering of the reaction force side mechanical system is accurately estimated and calculated, and the feeling of the steering wheel operation is made equal to the left and right according to the respective friction torques of the mechanical system during left-right steering. A steering reaction force control device and a steering reaction force control method capable of reducing a sense of incongruity with a steering wheel steering in a steer-by-wire type steering device by realizing highly accurate steering reaction force control as described above. be able to.

1 is an overall configuration diagram of a steering system including a vehicle steering control device according to Embodiment 1 of the present invention. It is a block diagram of the steering reaction force control apparatus which concerns on Embodiment 1 of this invention. It is a flowchart which shows a series of operation | movement of the steering reaction force control apparatus which concerns on Embodiment 1 of this invention. It is an internal block diagram of the steering state determination means which concerns on Embodiment 1 of this invention. It is a flowchart which shows a series of operation | movement of the steering state determination means which concerns on Embodiment 1 of this invention. It is an internal block diagram of the normal steering friction torque estimation means which concerns on Embodiment 1 of this invention. It is a flowchart which shows a series of operation | movement of the normal steering friction torque estimation means which concerns on Embodiment 1 of this invention. It is an internal block diagram of the negative steering friction torque estimation means which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows an example of the effect of the steering reaction force control apparatus which concerns on Embodiment 1 of this invention. It is an internal block diagram of the normal steering friction torque estimation means which concerns on Embodiment 2 of this invention. It is a flowchart which shows a series of operation | movement of the normal steering friction torque estimation means which concerns on Embodiment 2 of this invention. It is an internal block diagram of the negative steering friction torque estimation means which concerns on Embodiment 2 of this invention. It is explanatory drawing which shows an example of the effect of the steering reaction force control apparatus which concerns on Embodiment 2 of this invention. It is explanatory drawing which shows an example of the effect of the steering reaction force control apparatus which concerns on Embodiment 2 of this invention.

  Hereinafter, preferred embodiments of a steering reaction force control device and a steering reaction force control method of the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is an overall configuration diagram of a steering system including a vehicle steering control apparatus according to Embodiment 1 of the present invention. The steering system shown in FIG. 1 includes a handle 1, a handle angle sensor 2, a steering torque sensor 3, a reaction force gear box 4, a reaction force motor 5, a steered gear box 6, a steered motor 7, and a vehicle steering control device 8. The steering reaction force control device 9 included in the vehicle, the steering control device 10 included in the vehicle steering control device 8, the vehicle speed sensor 11, and the tire 12 are included. This steering system corresponds to a so-called steer-by-wire steering device in which the steering wheel 1 and the tire 12 are mechanically separated.

  The handle angle sensor 2 detects the angle of the handle operated by the driver. In the first embodiment, the following description will be made assuming that the handle angle when the handle is rotated to the right is positive, and the handle angle when the handle is rotated to the left is negative. However, the invention of the present application is not limited to this setting, and the setting may be reversed.

  The steering torque sensor 3 detects a steering torque applied to the handle 1 operated by the driver. The reaction force motor 5 is driven based on the reaction force current command value Irct_t from the steering reaction force control device 9. The output of the reaction force motor 5 is applied to the handle shaft as a torque that has been increased several times by the reaction force gear box 4.

  The vehicle steering control device 8 includes a steering reaction force control device 9 and a steering control device 10, and includes a device that communicates with other in-vehicle systems and the like, although not shown in the drawings.

  The steering reaction force control device 9 is included in the vehicle steering control device 8 and flows to the steering wheel angle θhdl that is the output of the steering wheel angle sensor 2, the steering torque Thdl that is the output of the steering torque sensor 3, and the reaction force motor 5. A reaction force current command value Irct_t that is a current command value to the reaction force motor 5 is output from the reaction force current Irct that is a current signal and the vehicle speed V that is the output of the vehicle speed sensor 11, and the voltage Vm is applied to the reaction force motor 5. To do.

  The steering control device 10 is included in the vehicle steering control device 8 and includes a steering wheel angle θhdl that is an output of the steering wheel angle sensor 2, a steering current Istr that is a current signal flowing through the steering motor 7, and a vehicle speed sensor 11. A steering current command value Istr_t that is a current command value to the steering motor 7 is output from the vehicle speed V that is the output and the steering angle θtire that is the output of the steering angle sensor included in the steering gear box 6. The voltage Vm is applied to the steering motor 7.

  The turning motor 7 is driven based on the turning current command value Istr_t from the turning control device 10. The output of the steered motor 7 is given to the rack via the steering shaft as torque that has been multiplied several times by the steered gear box 6. Although not shown in the drawing, a turning angle sensor for detecting the turning angle of the tire 12 is included in the turning gear box 6, and this turning angle sensor outputs a turning angle θtire. .

  The vehicle speed sensor 11 detects the traveling speed of the vehicle. In FIG. 1, the detection is based on the wheel speed of one wheel. However, the detection is not limited to this, and the vehicle travels based on an average of four wheel speeds, an average of right wheel speed, and an average of left wheel speed. You may ask for speed. The tire 12 is a vehicle front wheel that can be steered.

  Next, the structure which implement | achieves the steering reaction force control apparatus 9 by this Embodiment 1 is demonstrated. FIG. 2 is a configuration diagram of the steering reaction force control apparatus 9 according to Embodiment 1 of the present invention. The steering reaction force control device 9 according to the first embodiment includes a steering wheel angular velocity detection means 21, a steering state determination means 22, a positive steering friction torque estimation means 23, a negative steering friction torque estimation means 24, and a reaction force torque application means 25. It is prepared for.

  The steering wheel angular velocity detection means 21 calculates a steering wheel angular velocity ωhdl from the steering wheel angle θhdl. The steering wheel angular velocity ωhdl may be calculated using a known technique. In addition, information obtained by communication from a sensor or the like may be used.

  The steering state determination means 22 determines the steering state from the steering wheel angle θhdl, the steering wheel angular velocity ωhdl, and the steering torque Thdl, and outputs a steering state signal HdlSt.

  The positive steering friction torque estimating means 23 outputs the positive steering friction torque Tfric_pclm from the vehicle speed V, the steering torque Thdl, the steering wheel angle θhdl, the steering wheel angular velocity ωhdl, and the steering state signal HdlSt.

  The negative steering friction torque estimating means 24 outputs a negative steering friction torque Tfric_nclm from the vehicle speed V, the steering torque Thdl, the steering wheel angle θhdl, the steering wheel angular velocity ωhdl, and the steering state signal HdlSt.

  The reaction torque applying means 25 calculates and outputs a reaction force current command value Irct_t from the steering wheel angle θhdl, the steering wheel angular speed ωhdl, the vehicle speed V, the reaction force current Irct, the positive steering friction torque Tfric_pclm, and the negative steering friction torque Tfric_nclm.

  Specifically, the reaction force torque applying means 25 calculates a basic reaction force torque based on the steering wheel angle θhdl and the vehicle speed V. Next, the reaction force torque applying means 25 calculates a viscous resistance component according to the steering wheel angular velocity ωhdl. Next, the reaction force torque applying means 25 calculates a friction component to be applied or compensated from the steering wheel angle θhdl and the steering wheel angular velocity ωhdl using the positive steering friction torque Tfric_pclm and the negative steering friction torque Tfric_nclm.

  The reaction force current command value Irct_t is calculated as a current command value by combining the basic reaction force torque, the viscous resistance component, and the friction component. The reaction force torque applying means 25 controls the reaction force current command value Irct_t based on the difference between the reaction force current command value Irct_t and the reaction force current Irct. Each calculation of the basic reaction torque, the viscous resistance component, and the friction component may be performed using a map or the like, or may be performed by other known means.

  Next, a series of operations of the steering reaction force control device 9 according to the first embodiment will be described. FIG. 3 is a flowchart showing a series of operations of the steering reaction force control apparatus 9 according to Embodiment 1 of the present invention. First, in step S101, the steering reaction force control device 9 reads the steering wheel angle θhdl, the steering torque Thdl, and the vehicle speed V. Next, in step S102, the steering reaction force control device 9 calculates a steering wheel angular velocity ωhdl from the steering wheel angle θhdl.

  Next, in step S103, the steering reaction force control device 9 determines the steering state from the steering wheel angle θhdl, the steering torque Thdl, and the steering wheel angular velocity ωhdl, and outputs a steering state signal HdlSt. Next, in step S104, the steering reaction force control device 9 outputs a positive steering friction torque Tfric_pclm from the steering wheel angle θhdl, the steering torque Thdl, the steering wheel angular velocity ωhdl, and the steering state signal HdlSt.

  Next, in step S105, the steering reaction force control device 9 outputs a negative steering friction torque Tfric_nclm from the steering wheel angle θhdl, the steering torque Thdl, the steering wheel angular velocity ωhdl, and the steering state signal HdlSt.

  Finally, in step S106, the steering reaction force control device 9 determines the reaction force current command from the steering wheel angle θhdl, the steering wheel angular velocity ωhdl, the vehicle speed V, the reaction force current Irct, the positive steering friction torque Tfric_pclm, and the negative steering friction torque Tfric_nclm. The value Irct_t is output.

  Next, the internal configuration of the steering state determination unit 22 according to the first embodiment will be described in detail. FIG. 4 is an internal configuration diagram of the steering state determination unit 22 according to Embodiment 1 of the present invention. The steering state determination unit 22 according to the first embodiment includes a handle angle code determination unit 31, a handle rotation direction determination unit 32, a steering torque determination unit 33, and an increase / return determination unit 34.

  The handle angle code determination means 31 calculates a handle angle code signal HdlAglSign from the handle angle θhdl and outputs it. The handle angle code signal HdlAglSign is a signal expressing plus, 0, and minus of the handle angle θhdl. In the first embodiment, 1: handle angle plus, 0: handle angle 0, −1: handle angle minus, Explain.

  The steering wheel rotation direction determination means 32 calculates and outputs a steering wheel rotation direction signal HdlRotSign from the steering wheel angular velocity ωhdl. The steering wheel rotation direction signal HdlRotSign is a signal expressing plus, zero, and minus of the steering wheel angular velocity ωhdl. In the first embodiment, 1: steering wheel angular velocity plus, 0: steering wheel angular velocity 0, −1: steering wheel angular velocity minus, Explain.

  The steering torque determination means 33 calculates a steering torque determination signal HdlTrqJudge from the steering torque Thdl and outputs it. The steering torque determination signal HdlTrqJudge is a signal that represents the result of determining whether or not the magnitude of the steering torque Thdl is greater than a predetermined value. When the steering torque Thdl is equal to or greater than a predetermined value, it is assumed that the driver is operating, and the steering torque determination signal HdlTrqJudge is set to “1”. On the other hand, when the steering torque Thdl is smaller than the predetermined value, it is assumed that the driver has released his hand or is different from the normal situation, and the steering torque determination signal HdlTrqJudge is set to “0”.

  The increase / return determination means 34 calculates and outputs a steering state signal HdlSt from the handle angle code signal HdlAglSign, the handle rotation direction signal HdlRotSign, and the steering torque determination signal HdlTrqJudge. The steering state signal HdlSt is set to “1” at the time of additional turning, “−1” at the time of switching back, and “0” otherwise, and is determined according to Table 1 based on each signal.

  Next, a series of operations of the steering state determination unit 22 according to the first embodiment will be described. FIG. 5 is a flowchart showing a series of operations of the steering state determination means 22 according to Embodiment 1 of the present invention. First, in step S201, the steering state determination means 22 calculates a handle angle code signal HdlAglSign from the handle angle θhdl.

  Next, in step S202, the steering state determination unit 22 calculates a steering wheel rotation direction signal HdlRotSign from the steering wheel angular velocity ωhdl. Next, in step S203, the steering state determination means 22 calculates a steering torque determination signal HdlTrqJudge from the steering torque Thdl.

  Finally, in step S204, the steering state determination means 22 calculates a steering state signal HdlSt from the steering wheel angle code signal HdlAglSign, the steering wheel rotation direction signal HdlRotSign, and the steering torque determination signal HdlTrqJudge.

  Next, the internal configuration of the normal steering friction torque estimating means 23 according to the first embodiment will be described in detail. FIG. 6 is an internal configuration diagram of the normal steering friction torque estimating means 23 according to the first embodiment of the present invention. The positive steering friction torque estimating means 23 in the first embodiment includes a vehicle speed determining means 41, a predetermined steering wheel angle passage determining means 42, a predetermined steering wheel angular speed determining means 43, a positive steering increase steering torque calculating means 44, a positive switching return steering torque calculation. Means 45 and positive steering friction torque estimating means 46 are provided.

  The vehicle speed determination means 41 calculates a vehicle speed determination signal V_JdgSig from the vehicle speed V and outputs it. The vehicle speed determination signal V_JdgSig is a signal that determines whether or not the vehicle speed V is within a predetermined vehicle speed range.

  For example, the signal may be set to “1” when the vehicle speed V is within a predetermined vehicle speed range, and “0” when the vehicle speed V is not within the predetermined vehicle speed range. In addition, a case where a plurality of vehicle speed ranges are set in advance and the signals when the vehicle speed is in each set vehicle speed range is “1”, “2”, “3”... The signal may be “0”. In the present first embodiment, the following description will be made assuming that the vehicle speed determination signal V_JdgSig is “0” and “1”.

  The predetermined handle angle passage determination means 42 calculates a predetermined handle angle passage determination signal θhdl_JdgSig from the handle angle θhdl and outputs it. The predetermined handle angle passage determination signal θhdl_JdgSig is a signal that determines that the handle angle θhdl has reached a predetermined handle angle.

  For example, when the handle angle θhdl is set to ± 40 deg as a predetermined angle, the predetermined handle angle passage determination signal θhdl_JdgSig is “−1” when the handle angle θhdl is −40 deg, and predetermined when the handle angle θhdl is +40 deg. The steering wheel angle passage determination signal θhdl_JdgSig may be “1”, and may be “0” at other angles.

  In addition, a plurality of handle angles may be set as predetermined handle angles, and signals associated with the set handle angles may be used. In the first embodiment, the following description will be given on the assumption that the predetermined handle angle passage determination signal θhdl_JdgSig can take “−1”, “0”, and “1”.

  The predetermined steering wheel angular velocity determination means 43 calculates a predetermined steering wheel angular velocity determination signal ωhdl_JdgSig from the steering wheel angular velocity ωhdl and outputs it. The predetermined steering wheel angular velocity determination signal ωhdl_JdgSig is a signal that determines whether or not the steering wheel angular velocity ωhdl is within a predetermined steering wheel angular velocity range. For example, the signal may be set to “1” when the steering wheel angular velocity ωhdl is in a predetermined angular velocity range, and “0” when the steering wheel angular velocity ωhdl is not in the predetermined angular velocity range.

  The forward turning increase steering torque calculating means 44 calculates the forward turning increase steering torque Trq_ptnclm from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the predetermined steering wheel angular speed determination signal ωhdl_JdgSig, the steering state signal HdlSt, and the steering torque Thdl. ,Output.

  The vehicle speed determination signal V_JdgSig is “1: the vehicle speed is within a predetermined range”, the predetermined handle angle passage determination signal θhdl_JdgSig is “1: the predetermined handle angle on the positive side of the handle angle”, and the predetermined handle angle speed determination signal ωhdl_JdgSig is “1: The steering torque Thdl when the steering state signal HdlSt simultaneously satisfies “within a predetermined range” and the steering state signal HdlSt “1” is output as the steering torque Trq_ptnclm.

  The normal switchback steering torque calculation means 45 calculates a normal switchback steering torque Trq_prtnclm from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the predetermined steering wheel angular velocity determination signal ωhdl_JdgSig, the steering state signal HdlSt, and the steering torque Thdl. ,Output.

  The vehicle speed determination signal V_JdgSig is “1: the vehicle speed is within a predetermined range”, the predetermined handle angle passage determination signal θhdl_JdgSig is “1: the predetermined handle angle on the positive side of the handle angle”, and the predetermined handle angle speed determination signal ωhdl_JdgSig is “1: The steering torque Thdl when the steering state signal HdlSt satisfies “−1: switch back” simultaneously within the predetermined range is output as the normal switch back steering torque Trq_prtnclm.

  The positive steering friction torque estimating means 46 calculates and outputs the positive steering friction torque Tfric_pclm from the vehicle speed determination signal V_JdgSig, the positive cutting increase steering torque Trq_ptnclm, and the normal switching return steering torque Trq_prtnclm.

  The value of the positive steering friction torque Tfric_pclm is the magnitude of the difference between the positive cut-off steering torque Trq_ptnclm and the positive cut-back steering torque Trq_prtnclm when the signal of the vehicle speed determination signal V_JdgSig is “1: vehicle speed is within a predetermined range”. It is calculated as a half value and output.

  On the other hand, when the signal of the vehicle speed determination signal V_JdgSig is “0: the vehicle speed is out of the predetermined range”, the positive steering friction torque estimating means 46 does not newly calculate the difference, holds the previously calculated value, and performs the normal steering. Output as friction torque Tfric_pclm.

  Next, a series of operations of the normal steering friction torque estimating unit 23 in the first embodiment will be described. FIG. 7 is a flowchart showing a series of operations of the normal steering friction torque estimating means 23 according to the first embodiment of the present invention. First, in step S301, the positive steering friction torque estimating means 23 calculates a vehicle speed determination signal V_JdgSig from the vehicle speed V.

  Next, in step S302, the positive steering friction torque estimating means 23 calculates a predetermined steering wheel angle passage determination signal θhdl_JdgSig from the steering wheel angle θhdl. Next, in step S303, the positive steering friction torque estimating means 23 calculates a predetermined steering wheel angular velocity determination signal ωhdl_JdgSig from the steering wheel angular velocity ωhdl.

  Next, in step S304, the positive steering friction torque estimating means 23 positively increases from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the predetermined steering wheel angular velocity determination signal ωhdl_JdgSig, the steering state signal HdlSt, and the steering torque Thdl. Steering torque Trq_ptnclm is calculated.

  Next, in step S305, the positive steering friction torque estimating means 23 performs a normal back-turn steering from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the predetermined steering wheel angular velocity determination signal ωhdl_JdgSig, the steering state signal HdlSt, and the steering torque Thdl. Torque Trq_prtnclm is calculated.

  Finally, in step S306, the positive steering friction torque estimating means 23 calculates the positive steering friction torque Tfric_pclm from the vehicle speed determination signal V_JdgSig, the positive cut increasing steering torque Trq_ptnclm, and the positive cut back steering torque Trq_prtnclm.

  Next, the internal configuration of the negative steering friction torque estimating means 24 in the first embodiment will be described in detail. FIG. 8 is an internal configuration diagram of the negative steering friction torque estimating means 24 according to the first embodiment of the present invention. The negative steering friction torque estimating means 24 in the first embodiment includes a vehicle speed determining means 41, a predetermined handle angle passage determining means 42, a predetermined handle angular speed determining means 43, a negative cut increasing steering torque calculating means 51, and a negative switch back steering torque calculating. Means 52 and negative steering friction torque estimating means 53 are provided.

  The negative increase steering torque calculation means 51 calculates a negative increase steering torque Trq_ntnclm from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the predetermined steering wheel angular velocity determination signal ωhdl_JdgSig, the steering state signal HdlSt, and the steering torque Thdl. ,Output.

  The vehicle speed determination signal V_JdgSig is “1: the vehicle speed is within a predetermined range”, the predetermined handle angle passage determination signal θhdl_JdgSig is “−1: the predetermined handle angle on the negative side of the handle angle”, and the predetermined handle angle speed determination signal ωhdl_JdgSig is “1: the handle angular speed”. Is within the predetermined range ”and the steering state signal HdlSt is simultaneously“ 1: increased ”, the steering torque Thdl is increased negatively and output as the steering torque Trq_ntnclm.

  The negative switchback steering torque calculating means 52 calculates a negative switchback steering torque Trq_nrtnclm from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the predetermined steering wheel angular velocity determination signal ωhdl_JdgSig, the steering state signal HdlSt, and the steering torque Thdl. ,Output.

  The vehicle speed determination signal V_JdgSig is “1: the vehicle speed is within a predetermined range”, the predetermined handle angle passage determination signal θhdl_JdgSig is “−1: the predetermined handle angle on the negative side of the handle angle”, and the predetermined handle angle speed determination signal ωhdl_JdgSig is “1: the handle angular speed”. Is within the predetermined range and the steering state signal HdlSt satisfies “−1: switch back” at the same time, the steering torque Thdl is output as the negative switch back steering torque Trq_nrtnclm.

  The negative steering friction torque estimating means 53 calculates and outputs the negative steering friction torque Tfric_nclm from the vehicle speed determination signal V_JdgSig, the negative cut increase steering torque Trq_ntnclm, and the negative switchback steering torque Trq_ntnclm.

  The value of the negative steering friction torque Tfric_nclm is the magnitude of the difference between the negative turn-up steering torque Trq_ntnclm and the negative switchback steering torque Trq_nrtnclm when the signal of the vehicle speed determination signal V_JdgSig is “1: vehicle speed is within a predetermined range”. Is calculated and output as a half value.

  On the other hand, if the signal of the vehicle speed determination signal V_JdgSig is “0: the vehicle speed is out of the predetermined range”, the negative steering friction torque estimating means 53 does not newly calculate a difference, holds the previously calculated value, and performs negative steering. Output as friction torque Tfric_nclm.

  The operation of the negative steering friction torque estimating unit 24 is similar to the operation of the positive steering friction torque estimating unit 23 except for the signs of “positive” and “negative”, and thus the description thereof is omitted here.

  FIG. 9 is an explanatory diagram showing an example of the effect of the steering reaction force control apparatus according to the first embodiment of the present invention. FIG. 9A in the upper part shows the steering torque Thdl with respect to the steering wheel angle θhdl, and FIG. 9B in the lower part shows the reaction force side friction torque Tfric_clm with respect to the steering wheel angle θhdl.

  In the steering torque Thdl with respect to the steering wheel angle θhdl shown in FIG. 9A, the predetermined steering wheel angle is indicated by “x” in the drawing, and the steering torque and the return when passing through the predetermined steering wheel angle during the turning increase. A value half of the difference in steering torque when passing through a predetermined steering wheel angle is calculated as positive and negative friction torque. As a result, the value of the reaction force side friction torque Tfric_clm with respect to the handle angle θhdl can be detected as a different value depending on whether the handle angle θhdl is positive or negative.

  As described above, according to the first embodiment, it is possible to detect the reaction force side friction torque with the steering wheel angle being positive and negative. As a result, it is possible to obtain a steering reaction force control device that makes the feeling of steering wheel operation (steering responsiveness) equal to the left and right and does not give the driver a feeling of strangeness in vehicle behavior.

Embodiment 2. FIG.
The overall configuration for realizing the vehicle steering control apparatus according to the second embodiment is the same as that of FIG. Here, only different points from the first embodiment will be described.

  The internal configuration of the normal steering friction torque estimating means 23 according to the second embodiment will be described in detail. FIG. 10 is an internal configuration diagram of the normal steering friction torque estimating means 23 according to the second embodiment of the present invention. The positive steering friction torque estimating means 23 in the second embodiment includes a vehicle speed determining means 41, a predetermined steering wheel angle passage determining means 42, a predetermined steering wheel angular speed determining means 43, and a positive steering increasing steering torque calculation as in the first embodiment. In addition to the means 44 and the normal switching return steering torque calculating means 45, the apparatus further comprises a positive cutting increase steering torque correction means 111, a normal switching return steering torque correction means 112, and an angle-corresponding positive steering friction torque estimation means 113. ing. Here, the description of the same configuration as in the first embodiment is omitted.

  The predetermined handle angle passage determination signal θhdl_JdgSig, which is the output of the predetermined handle angle passage determination unit 42 in the second embodiment, sets a plurality of handle angles as predetermined handle angles and is a signal associated with each set handle angle. . In the second embodiment, the predetermined handle angle passage determination signal θhdl_JdgSig is “−3: −90 deg”, “−2: −60 deg”, “−1: −30 deg”, “0: other”, “1: +30 deg”. The following description will be given as a signal taking “2: +60 deg” and “3: +90 deg”.

  The forward increase steering torque calculating means 44 according to the second embodiment is when the condition of the predetermined steering wheel angle passage determination signal in the first embodiment is “1”, “2”, or “3”. It is what.

  Further, the normal switching steering torque calculating means 45 in the second embodiment satisfies any one of “1”, “2”, and “3” as the condition of the predetermined steering wheel angle passage determination signal in the first embodiment. This is the case.

  The forward cut increasing steering torque correcting means 111 outputs a forward cut increasing steering torque correction value Trq_ptnclm_cor from the forward cut increasing steering torque Trq_ptnclm and the steering wheel angular velocity ωhdl.

  In the forward-turn increasing steering torque correction calculation, a correction constant output based on the steering wheel angular velocity ωhdl is set in advance on a map or the like, and the forward-turn increasing steering torque Trq_ptnclm is multiplied or divided by the correction constant to increase the forward-turn increasing steering. Torque correction value Trq_ptnclm_cor is calculated. In addition, although correction calculation by addition and subtraction may be performed using correction constants, in the second embodiment, the following description will be given as correction by multiplication.

  The normal switchback steering torque correction means 112 outputs a normal switchback steering torque correction value Trq_prtnclm_cor from the normal switchback steering torque Trq_prtnclm and the steering wheel angular velocity ωhdl.

  In the normal return steering torque correction calculation, similarly to the normal increase steering torque correction calculation, a correction constant output based on the steering wheel angular velocity ωhdl is set in advance using a map or the like, and the correction constant is set to the normal return steering torque Trq_prtnclm. Is multiplied or divided to calculate a normal switchback steering torque correction value Trq_prtnclm_cor. In addition, although correction calculation by addition and subtraction may be performed using correction constants, in the second embodiment, the following description will be given as correction by multiplication.

  The angle-corresponding positive steering friction torque estimating means 113 calculates the positive steering friction torque Tfric_pc from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the positive-turn increase steering torque correction value Trq_ptnclm_cor, and the positive-turn-back steering torque correction value Trq_prtnclm_cor. Is output.

  The value of the positive steering friction torque Tfric_pclm is calculated as follows: when the signal of the vehicle speed determination signal V_Jdgsig is “1: the vehicle speed is within a predetermined range”, the steering torque correction value Trq_ptnclm_cor and the steering torque correction value Trq_prtnclm_cor are increased. It is calculated as a half value of the difference, stored corresponding to the value of the predetermined steering wheel angle passage determination signal θhdl_JdgSig, and output as a positive steering friction torque Tfric_pclm corresponding to the predetermined steering wheel angle. For the positive steering friction torque Tfric_pclm, for example, a vector type variable as shown in Table 2 below may be used.

  On the other hand, when the signal of the vehicle speed determination signal V_JdgSig is “0: the vehicle speed is out of the predetermined range”, the angle-corresponding positive steering friction torque estimating means 113 does not newly calculate the difference but holds the previously calculated value. , And output as a positive steering friction torque Tfric_pclm.

  Next, a series of operations of the positive steering friction torque estimating means 23 in the second embodiment will be described. FIG. 11 is a flowchart showing a series of operations of the normal steering friction torque estimating means 23 according to the second embodiment of the present invention. First, in step S701, the positive steering friction torque estimating means 23 calculates a vehicle speed determination signal V_JdgSig from the vehicle speed V.

  Next, in step S702, the positive steering friction torque estimating means 23 calculates a predetermined steering wheel angle passage determination signal θhdl_JdgSig from the steering wheel angle θhdl. Next, in step S703, the positive steering friction torque estimating means 23 calculates a predetermined steering wheel angular velocity determination signal ωhdl_JdgSig from the steering wheel angular velocity ωhdl.

  Next, in step S704, the positive steering friction torque estimating means 23 performs a positive steering operation from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the predetermined steering wheel angular velocity determination signal ωhdl_JdgSig, the steering state signal HdlSt, and the steering torque Thdl. Torque Trq_ptnclm is calculated.

  Next, in step S705, the positive steering friction torque estimating means 23 performs a normal back-turn steering from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the predetermined steering wheel angular velocity determination signal ωhdl_JdgSig, the steering state signal HdlSt, and the steering torque Thdl. Torque Trq_prtnclm is calculated.

  Next, in step S706, the normal steering friction torque estimating means 23 outputs the normal steering increased steering torque correction value Trq_ptnclm_cor from the normal steering increased steering torque Trq_ptnclm and the steering wheel angular velocity ωhdl. Next, in step S707, the normal steering friction torque estimating means 23 outputs a normal switching steering torque correction value Trq_prtnclm_cor from the normal switching steering torque Trq_prtnclm and the steering wheel angular velocity ωhdl.

  Finally, in step S708, the positive steering friction torque estimating means 23 determines from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the positive turning increase steering torque correction value Trq_ptnclm_cor, and the positive turning back steering torque correction value Trq_prtnclm_cor. The positive steering friction torque Tfric_pclm is output.

  Next, the internal configuration of the negative steering friction torque estimating means 24 in the second embodiment will be described in detail. FIG. 12 is an internal configuration diagram of the negative steering friction torque estimating means 24 according to the second embodiment of the present invention. The negative steering friction torque estimating means 24 in the second embodiment includes a vehicle speed determination means 41, a predetermined handle angle passage determination means 42, a predetermined handle angular speed determination means 43, and a negative steering increase steering torque calculation similar to those in the first embodiment. In addition to the means 51 and the negative switchback steering torque calculation means 52, a negative switch increase steering torque correction means 121, a negative switchback steering torque correction means 122, and an angle corresponding negative steering friction torque estimation means 123 are further provided. Yes. Here, the description of the same configuration as in the first embodiment is omitted.

  The negative increase steering torque calculating means 51 according to the second embodiment is set to any one of “−1”, “−2”, and “−3” as the condition of the predetermined steering wheel angle passage determination signal in the first embodiment. It is assumed that it is established.

  Further, the negative switchback steering torque calculation means 52 in the second embodiment sets the condition of the predetermined steering wheel angle passage determination signal in the first embodiment to any one of “−1”, “−2”, and “−3”. This is the case where is established.

  The negative increase steering torque correction means 121 outputs a negative increase increase steering torque correction value Trq_ntnclm_cor from the negative increase steering torque Trq_ntnclm and the steering wheel angular velocity ωhdl.

  In the negative turning increase steering torque correction calculation, a correction constant output based on the steering wheel angular velocity ωhdl is set in advance on a map or the like, and the negative turning increase steering torque Trq_ntnclm is multiplied or divided by the correction constant to thereby increase the negative cut steering. Torque correction value Trq_ntnclm_cor is calculated. In addition, although correction calculation by addition and subtraction may be performed using a correction constant, in the second embodiment, the following description will be given as correction by multiplication.

  The negative switchback steering torque correction means 122 outputs a negative switchback steering torque correction value Trq_nrtnclm_cor from the negative switchback steering torque Trq_nrtnclm and the steering wheel angular velocity ωhdl.

  In the negative switchback steering torque correction calculation, similarly to the negative switch increase steering torque correction calculation, a correction constant output based on the steering wheel angular velocity ωhdl is set in advance using a map or the like, and the negative switchback steering torque Trq_nrtnclm is corrected to the correction constant. Is multiplied or divided to calculate the normal switchback steering torque correction value Trq_nrtnclm_cor. In addition, although correction calculation by addition and subtraction may be performed using correction constants, in the second embodiment, the following description will be given as correction by multiplication.

  The angle-corresponding negative steering friction torque estimating means 123 calculates the negative steering friction torque Tfric_nc1 from the vehicle speed determination signal V_JdgSig, the predetermined steering wheel angle passage determination signal θhdl_JdgSig, the negative cut increase steering torque correction value Trq_ntnclm_cor, and the negative switchback steering torque correction value Trq_ntrtlmm_cor. Output.

  The value of the negative steering friction torque Tfric_nclm is obtained by adding a negative cut-off steering torque correction value Trq_ntnclm_cor and a negative switchback steering torque correction value Trq_ntrtlmm_cor when the signal of the vehicle speed determination signal V_JdgSig is “1: vehicle speed is within a predetermined range”. It is calculated as a half value of the difference, stored corresponding to the value of the predetermined steering wheel angle passage determination signal θhdl_JdgSig, and output as a negative steering friction torque Tfric_nclm corresponding to the predetermined steering wheel angle.

  As the negative steering friction torque Tfric_nclm, for example, a vector type variable as shown in Table 3 below may be used. On the other hand, when the signal of the vehicle speed determination signal V_JdgSig is “0: the vehicle speed is out of the predetermined range”, the angle-corresponding negative steering friction torque estimating means 123 does not newly calculate the difference but holds the previously calculated value. , And output as negative steering friction torque Tfric_nclm.

  The operation of the negative steering friction torque estimating means 24 is similar to that of the operation of the positive steering friction torque estimating means 23 except that the signs of “positive” and “negative” are different. To do.

  FIG. 13 is an explanatory diagram showing an example of the effect of the steering reaction force control apparatus according to Embodiment 2 of the present invention, and shows the effect when the steering speed is fast. FIG. 13A in the upper stage shows the steering torque Thdl with respect to the handle angle θhdl, and FIG. 13B in the lower stage shows the reaction force side friction torque Tfric_clm with respect to the handle angle θhdl.

  The reaction force side of FIG. 13A shows two cases of “without torque correction” and “with torque correction” according to the steering speed in the steering torque Thdl with respect to the steering wheel angle θhdl.

  In the case where there is no torque correction, the torque width at the time of turning back and turning up differs from normal due to a phase shift of the torque with respect to the steering wheel angle. As a result, when the friction torque Tfric_clm on the reaction force side is calculated, an error becomes larger than the actual friction torque (dotted line). On the other hand, in the case of “with torque correction”, it is possible to correct the torque width at the time of increase / return as much as normal, so that the friction torque on the reaction force side can be detected with high accuracy.

  Next, FIG. 14 is explanatory drawing which shows an example of the effect of the steering reaction force control apparatus which concerns on Embodiment 2 of this invention, and has shown the effect at the time of calculating for every steering angle. 14A of the upper stage shows the steering torque Thdl with respect to the steering wheel angle θhdl, and FIG. 14B of the lower stage shows the reaction force side friction torque Tfric_clm with respect to the steering wheel angle θhdl.

  In FIG. 14, since the friction torque on the reaction force side corresponding to the steering wheel angle is calculated, the actual reaction force side friction torque is compared with the friction torque calculated when the angle correspondence is not performed (one point only on the left and right). The error from the friction torque is small, and it can be detected with high accuracy.

  As described above, according to the second embodiment, it is possible to accurately detect the reaction force side friction torque with the handle angles being in a predetermined state. Furthermore, by performing torque correction according to the steering speed, it is possible to detect the reaction-side friction torque with high accuracy. As a result, a steering reaction force control device can be obtained in which the feeling of steering wheel operation is made to be equal to the left and right with high accuracy, and the driver does not feel uncomfortable with respect to the vehicle behavior.

  1 steering wheel, 2 steering wheel angle sensor, 3 steering torque sensor, 4 reaction force gear box, 5 reaction force motor, 6 steering gear box, 7 steering motor, 8 vehicle steering control device, 9 steering reaction force control device, 10 Steering control device, 11 vehicle speed sensor, 12 tire, 21 steering wheel angular velocity detecting means, 22 steering state determining means, 23 positive steering friction torque estimating means, 24 negative steering friction torque estimating means, 25 reaction force torque applying means, 31 steering wheel angle Sign determining means 32 Steering wheel rotational direction determining means 33 Steering torque determining means 34 Increase / return determination means 41 Vehicle speed determination means 42 Predetermined handle angle passage determination means 43 Predetermined handle angular speed determination means 44 Increase forward cut Steering torque calculation means, 45 Forward switching back steering torque calculation means, 46 Positive steering friction torque estimation , 51 Negative cut increase steering torque calculation means, 52 Negative switch return steering torque calculation means, 53 Negative steering friction torque estimation means, 111 Positive cut increase steering torque correction means, 112 Positive switch return steering torque correction means, 113 Angle-compatible type Positive steering friction torque estimation means, 121 Negative cut increase steering torque correction means, 122 Negative switch back steering torque correction means, 123 Angle corresponding negative steering friction torque estimation means

Claims (9)

A steering reaction force control device applied to a steer-by-wire vehicle in which an automobile handle and a tire are mechanically separated,
When the steering wheel angle is positive and the steering torque passes through the positive predetermined steering angle while the steering state is increasing, and when the steering state passes through the positive predetermined steering wheel angle during the switching back Positive steering friction torque estimating means for estimating half the difference from the steering torque as the positive steering friction torque;
When the steering wheel angle is negative and the steering state passes through a negative predetermined steering angle while the steering state is increased, and when the steering state passes through the negative predetermined steering angle while the steering state is switched back. Negative steering friction torque estimating means for estimating half the difference from the steering torque as negative steering friction torque;
Based on the positive steering friction torque estimated and calculated by the positive steering friction torque estimating means and the negative steering friction torque estimated and calculated by the negative steering friction torque estimating means, the steering response in left and right steering is A steering reaction force control device comprising: reaction force torque applying means for calculating reaction force torque to be equal. A steering reaction force control device applied to a steer-by-wire vehicle in which an automobile handle and a tire are mechanically separated,
Vehicle speed detecting means for detecting a vehicle speed that is the traveling speed of the automobile;
Handle angle detection means for detecting the angle of the handle as positive when rotating the handle in the right direction and negative when rotating in the left direction;
Handle angular velocity detection means for detecting the angular velocity of the handle;
Steering torque detection means for detecting a steering torque borne by the driver when steering the steering wheel;
Based on the steering wheel angle detected by the steering wheel angle detection means, the steering wheel angular speed detected by the steering wheel angular speed detection means, and the vehicle speed detected by the vehicle speed detection means, the steering wheel is returned to the neutral direction. Reaction force torque applying means for calculating a reaction force torque and applying the reaction force torque to the reaction force motor;
Based on the steering wheel angle detected by the steering wheel angle detection means, the steering wheel angular speed detected by the steering wheel angular velocity detection means, and the steering torque detected by the steering torque detection means, the steering state is Steering state determination means for determining whether the state is an increased cutting state or a switched back state;
The steering wheel angle detected by the steering wheel angle detecting means is in a positive state, the steering state determined by the steering state determining means is in an increased state, and the steering wheel angle is at least one positive angle. The steering torque detected by the steering torque detection means is positively increased to a steering torque, and the steering wheel angle detected by the steering wheel angle detection means is in a positive state. When the steering state determined by the steering state determination unit is a switchback state and the steering wheel angle passes the positive predetermined steering wheel angle, the steering torque detected by the steering torque detection unit is positive. When the steering wheel angle is positive from the half of the absolute value of the difference between the positive steering torque and the positive steering torque, A positive steering friction torque estimating means for estimating and calculating a positive steering friction torque applied between the handle and the reaction force torque applying means; and the handle angle detected by the handle angle detecting means is in a negative state, The steering detected by the steering torque detecting means when the steering state determined by the steering state determining means is an increased state and the handle angle has passed at least one negative predetermined handle angle. The steering angle is increased to a negative torque to obtain a steering torque, the steering wheel angle detected by the steering wheel angle detecting means is in a negative state, the steering state determined by the steering state determining means is a switchback state, and the steering wheel The steering torque detected by the steering torque detecting means when the angle of the negative predetermined steering angle has passed the negative steering angle, The negative steering friction torque applied between the steering wheel and the reaction force torque applying means when the steering wheel angle is negative from the half of the absolute value of the difference between the negative steering additional steering torque and the negative switching back steering torque. Negative steering friction torque estimating means for performing estimation calculation,
The reaction force torque applying means is based on the positive steering friction torque estimated and calculated by the positive steering friction torque estimating means and the negative steering friction torque estimated and calculated by the negative steering friction torque estimating means. A steering reaction force control device that calculates the reaction force torque so that the steering response in steering is equal to the left and right. In the steering reaction force control device according to claim 2,
The positive steering friction torque estimating means estimates and calculates the positive steering friction torque when the vehicle speed is within a predetermined first range,
The negative steering friction torque estimating means estimates and calculates the negative steering friction torque when the vehicle speed is within the first range. In the steering reaction force control device according to claim 2 or 3,
When the vehicle speed is within a predetermined second range, the normal steering friction torque estimating means updates the normal cutting increase steering torque and the normal switching return steering torque, and based on the latest data after the update. Estimating the positive steering friction torque,
The negative steering friction torque estimating means updates the negative cut increasing steering torque and the negative cut back steering torque when the vehicle speed is within the second range, and updates the negative steering friction torque based on the latest data after the update. Steering reaction force control device that estimates steering friction torque. In the steering reaction force control device according to claim 4,
The positive steering friction torque estimating means includes
Correcting the increased normal steering torque based on a correction coefficient corresponding to the operation state of the steering wheel, and correcting the increased positive steering torque to output a positive torque correction value.
Correct re-turn steering torque updated based on the correction constant, and normal re-turn steering torque correction means for outputting a normal re-turn steering torque correction value; and The positive steering friction torque is estimated and calculated from a half value of the absolute value of the difference from the normal switchback steering torque correction value,
The negative steering friction torque estimating means includes
A negative cut increase steering torque correcting means for correcting the updated negative cut increase steering torque based on the correction coefficient and outputting a negative cut increase steering torque correction value;
A negative switchback steering torque correction unit that corrects the updated negative switchback steering torque based on the correction constant and outputs a negative switchback steering torque correction value; and A steering reaction force control apparatus that estimates and calculates the negative steering friction torque from a value that is half the absolute value of the difference from the negative switchback steering torque correction value. In the steering reaction force control device according to claim 5,
The positive steering friction torque estimating means and the negative steering friction torque estimating means perform a correction calculation by employing a value corresponding to the angular velocity of the steering wheel detected by the steering wheel angular velocity detecting means as the correction constant. Control device. In the steering reaction force control device according to claim 6,
The positive steering friction torque estimating means associates the calculated positive steering friction torque with the positive predetermined handle angle,
The negative steering friction torque estimating means associates the estimated negative steering friction torque with the negative predetermined steering wheel angle steering reaction force control device. In the steering reaction force control device according to claim 7,
The steering state determining means determines whether the steering state is an increased steering wheel state or a switched back state when the steering torque detected by the steering torque detector is equal to or greater than a predetermined value. Steering reaction force control device. A steering reaction force control method applied to a steer-by-wire vehicle in which a steering wheel and a tire of an automobile are mechanically separated,
When the steering wheel angle is positive and the steering torque passes through the positive predetermined steering angle while the steering state is increasing, and when the steering state passes through the positive predetermined steering wheel angle during the switching back A positive steering friction torque estimation step for estimating half the difference from the steering torque as a positive steering friction torque;
When the steering wheel angle is negative and the steering state passes through a negative predetermined steering angle while the steering state is increased, and when the steering state passes through the negative predetermined steering angle while the steering state is switched back. A negative steering friction torque estimating step for estimating half the difference from the steering torque as a negative steering friction torque;
Based on the positive steering friction torque estimated in the positive steering friction torque estimation step and the negative steering friction torque estimated in the negative steering friction torque estimation step, the steering responsiveness in left and right steering is A steering reaction force control method comprising: a reaction force torque applying step for calculating reaction force torque so as to be uniform.

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