JP2016078849A - Vehicular steering support apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular steering support apparatus for controlling adjusting force on the basis of a change rate of the energy in a steering system.SOLUTION: A vehicular steering support apparatus includes: a transmission device for transmitting force and shift in relation to steering between a steering wheel and steering wheels; a power steering wheel for giving assist torque to the transmission device; and a control device. The vehicular steering support apparatus further includes the steering wheel, transmission device, power steering device and steering wheel as a steering system, computes a change rate dDE of energy in the steering system on the basis of a product of a steering angular velocity and a differential value of steering angular velocity, that of the steering angular velocity and steering torque, and that of a steering angle and a differential value of the steering torque, and controls assist torque on the basis of the change rate dDE of energy in the steering system.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a steering assist device for a vehicle, and more particularly to a steering assist device that assists steering by adjusting a force related to steering.

  In general, a vehicle such as an automobile is equipped with a steering assist device that assists steering by adjusting a steering-related force such as a steering assist force. It is desirable that this type of steering assist device not only reduce the driver's steering burden, but also adjust the steering force in response to the driver's intention.

  For example, in the following Patent Document 1 relating to the application of the present applicant, the steering power is calculated, and the steering power adjustment is changed depending on whether the steering power is larger than a reference value. A support device is described. In particular, the steering power is calculated as the sum of the product of the steering angular velocity and the steering torque and the product of the steering angle and the differential value of the steering torque. According to the steering assist device described in Patent Literature 1, it is possible to adjust the steering force by reflecting the driver's intention better than when the magnitude of the steering power is not taken into consideration.

International Publication No. 2014-087546

[Problems to be Solved by the Invention]
However, even if it is determined whether the magnitude of the steering power is larger than the reference value according to the configuration described in Patent Document 1, the adjustment of the force related to steering cannot be appropriately changed according to the steering situation. There is a case.

  For example, even if steering is started in a situation where the steering wheel is in the neutral range (straight position of the vehicle or in the vicinity thereof), the steering torque is not generated immediately, and in the steering range where the steering range from the neutral position is small, The steering power is very small. Therefore, in situations where the steering wheel is in the neutral range, even if it is determined whether or not the steering power is larger than the reference value, the adjustment of the force related to steering should be appropriately changed according to the steering situation. I can't.

  In addition, when the driver rotates the steering wheel in the neutral range while resisting self-aligning torque, appropriate resistance and damping force against the rotation of the steering wheel are provided so that the driver can stably perform the steering operation. Preferably it is given. On the other hand, when the steering wheel is rotated toward the neutral position by the self-aligning torque in the vicinity of the neutral position, the drag force against the rotation of the steering wheel is low so that the steering wheel quickly returns to the neutral position. Is preferred.

  However, depending on the configuration described in Patent Document 1, when the steering wheel is rotating toward the neutral position in the vicinity of the neutral position, whether the rotation of the steering wheel is due to the driver's operation or not is possible. It cannot be determined whether it is due to lining torque. Therefore, the steering drag and the like cannot be changed appropriately according to the steering situation. In addition, in order to distinguish and determine the above situation, it is necessary to determine whether or not the driver has released his hand from the steering wheel.

  Furthermore, when the steering wheel is rotated by the driver's steering operation and the steering wheel is also rotated by the force received from the road surface such as self-aligning torque, the steering torque is low if the rotation directions are the same. It can only be a value. Therefore, the magnitude of the steering power is very small, so even if it is determined whether the magnitude of the steering power is larger than the reference value, the adjustment of the force related to steering should be appropriately changed according to the steering situation. I can't.

The present invention has been made in view of the above-described circumstances in the steering assist device described in Patent Document 1. And the main subject of this invention is providing the steering assistance apparatus improved regarding the said.
[Means for Solving the Problems and Effects of the Invention]

  According to one embodiment of the present invention, steering including a steering wheel operated by a driver, a steering wheel, and a transmission device that transmits steering force and displacement between the steering wheel and the steering wheel. An adjustment force applying device that is applied to a vehicle equipped with the device and applies an adjustment force for adjusting a force related to steering to the transmission device; A steering assist device for a vehicle having a steering angle detection device for detecting a steering angle and a steering torque detection device for detecting a steering torque. The control device includes a steering angular velocity, a differential value of the steering angular velocity, and a steering torque. Differential value of the steering wheel, transmission device, adjustment force applying device, steering wheel as a steering system, the product of the steering angular velocity and the differential value of the steering angular velocity, the steering angular velocity and the steering torque. Steering for a vehicle that calculates the rate of change of the energy of the steering system based on the product of the steering wheel and the product of the steering angle and the differential value of the steering torque, and controls the adjustment force based on the rate of change of the energy of the steering system A support device is provided.

  According to the above configuration, the rate of change in the energy of the steering system based on the product of the steering angular velocity and the differential value of the steering angular velocity, the product of the steering angular velocity and the steering torque, and the product of the steering angle and the differential value of the steering torque. Is calculated, and the adjustment force is controlled based on the rate of change of the energy of the steering system. Since the rate of change of energy in the steering system represents the direction and degree of energy input to the steering system, the adjustment force can be controlled in accordance with the direction and degree of energy input to the steering system. As will be described in detail later, the input energy of the steering system depends on whether the rate of change in the energy of the steering system is a large value for the increase rate of change or a large value for the rate of change of the decrease. It can be determined whether the input is a positive input by the driver's steering or a reverse input by the steering wheel receiving a force from the road surface.

  In particular, the rate of change of the energy of the steering system is calculated based on the product of the steering angular velocity and the differential value of the steering angular velocity. The steering angular velocity and the differential value of the steering angular velocity change more greatly than the steering torque and the differential value thereof even when steering is started in a situation where the steering wheel is in the neutral range. Therefore, compared to the determination based on the steering power described in Patent Document 1 that does not include the product of the steering angular velocity and the differential value of the steering angular velocity, in the situation where the steering wheel is in the neutral range, Accordingly, the adjustment force can be appropriately controlled.

  Further, the situation in which the steering wheel rotates can be determined at an early stage as compared with the case where the product of the steering angular velocity and the differential value of the steering angular velocity is not taken into consideration. Therefore, for example, even when the driver starts a fast steering operation, the situation of the positive input can be determined at an early stage to control the adjustment force, thereby effectively assisting the driver's steering. Also, when the driver releases his hand from the steering wheel at the end of turning and the steering wheel is returned to the neutral position quickly by the self-aligning torque in the vicinity of the neutral position, the situation of the reverse input is judged early, and the steering wheel The adjustment force can be controlled so that the drag force against the rotation of the wheel is reduced. In this case, it is not necessary to determine whether or not the situation is let go.

  Furthermore, when the steering wheel is rotated by the driver's steering operation (positive input) and the steering wheel is also rotated by the force received from the road surface (reverse input), and the rotation directions thereof are the same, the steering torque Is only low, but the steering wheel rotates. According to the above configuration, since the product of the steering angular velocity and the differential value of the steering angular velocity is taken into consideration, it is possible to determine the situation of the rotation in the same direction as described above. Therefore, the positive input and the reverse input to the steering system are in phase. Even in this case, the adjustment force can be controlled.

  In the above configuration, the control device is a product of the inertia yaw moment, the steering angular velocity, and the differential value of the steering angular velocity based on the mass of the movable member constituting the steering system and including at least the steering wheel, the steering angular velocity and the steering. The product of the torque and the differential value of the sum of the products of the steering angle and the steering torque may be calculated as the rate of change of the steering system energy.

  According to the above configuration, as will be described in detail later, the rate of change in the energy of the steering system is calculated as the sum of the rotational energy and elastic energy corresponding to the internal energy and PV work in the enthalpy theory of thermodynamics, respectively. be able to. Therefore, it is possible to accurately determine whether the energy flows into and out of the steering system, that is, whether the energy input status to the steering system is a positive input or a reverse input.

  Further, in the above configuration, the adjustment force is a steering assist force, and the control device is configured such that when the rate of change of the steering system energy is the increase rate of change, the rate of change of the steering system energy is the rate of change of the increase. The steering assist force may be increased as compared with the case where there is not.

  According to the above configuration, when the rate of change of the energy of the steering system is the rate of change of the increase, that is, when the energy flows into the steering system, the rate of change of the energy of the steering system is not the rate of change of the increase. Thus, the steering assist force can be increased. Therefore, when the steering operation is performed by the driver, the assist of the driver's steering operation can be increased by correcting the increase of the steering assist force, and the driver can easily perform the steering operation.

  In the above configuration, the adjustment force is at least one of the steering damping force and the steering friction force. When the change rate of the steering system energy is the decrease change rate, the control device determines that the change rate of the steering system energy is Compared to when the rate of change is not the decrease, at least one of the steering damping force and the steering friction force may be increased.

  According to the above configuration, when the rate of change of the steering system energy is a decrease rate of change, the steering damping force and the steering friction force are smaller than when the rate of change of the steering system energy is not the rate of change of the decrease. At least one can be increased. Therefore, when the steering operation is not performed by the driver, at least one of the steering damping force and the steering friction force is increased, and the degree to which the steering wheel is rotated by the disturbance that the steering wheel receives from the road surface is reduced, thereby stabilizing the steering. Can be improved.

  Further, in the above configuration, the control device is in a situation where the input state of energy to the steering system is a positive input state by the driver's steering or a reverse input state due to the steering wheel receiving force from the road surface. The steering assist force is corrected so that the magnitude of the correction amount of the steering assist force in the reverse input situation is smaller than the magnitude of the correction amount of the steering assist force in the positive input situation. You may change the amount.

  According to the above configuration, since the steering assist force is controlled based on both the rate of change of the energy of the steering system and the input state of energy to the steering system, the ratio of the case where the input state of energy to the steering system is not determined. Thus, the steering assist force can be controlled more preferably. That is, when the input state of energy to the steering system is a positive input state due to the driver's steering, the amount of correction of the steering assist force should be made smaller than in the case of a reverse input state. Therefore, the possibility that the steering assist force becomes excessive can be reduced.

  Further, in the above configuration, the control device is in a situation where the input state of energy to the steering system is a positive input state by the driver's steering or a reverse input state due to the steering wheel receiving force from the road surface. The magnitude of the correction amount of at least one of the steering damping force and the steering friction force in the reverse input situation is the magnitude of the correction amount of at least one of the steering damping force and the steering friction force in the positive input situation. The amount of correction of at least one of the steering damping force and the steering friction force may be changed so as to be larger than that.

  According to the above configuration, since at least one of the steering damping force and the steering friction force is controlled based on both the rate of change of the energy of the steering system and the input state of energy to the steering system, the energy of the steering system is Compared to the case where the input state is not determined, at least one of the steering damping force and the steering friction force can be controlled more preferably. That is, the magnitude of the correction amount of at least one of the steering damping force and the steering friction force in the reverse input situation is compared with the magnitude of the correction amount of at least one of the steering damping force and the steering friction force in the positive input situation. And big. Therefore, in the reverse input situation, at least one of the steering damping force and the steering friction force is further increased compared to the positive input situation, and the steering wheel may be more effectively rotated by the disturbance received from the road surface. Can be reduced.

  In the above configuration, the control device determines whether the input state of energy to the steering system depends on the driver's steering based on the product of the steering torque, the differential value of the steering torque, and the rate of change of the steering system energy. It may be determined whether the situation is a positive input or a reverse input due to the steering wheel receiving a force from the road surface.

  According to the above configuration, the state of energy input to the steering system is a positive input state using the rate of change of the energy of the steering system and the steering torque used for the calculation and the differential value of the steering torque. It is possible to determine whether or not the situation is reverse input. Further, a special device for determining the input direction such as two torque sensors is not necessary.

It is a figure showing the outline of a first embodiment of the steering assistance device for vehicles by the present invention. It is a block diagram of the assist torque calculating apparatus which calculates assist torque Ta in 1st embodiment. 3 is a flowchart for calculating a correction gain by a correction gain calculation block shown in FIG. 2. It is a block diagram of the assist torque calculating apparatus which calculates assist torque Ta in 2nd embodiment of the steering assistance apparatus for vehicles by this invention. 10 is a flowchart (first half) for calculating a correction gain by a correction gain calculation block in the second embodiment. 10 is a flowchart (second half) for calculating a correction gain by a correction gain calculation block in the second embodiment. It is a figure which shows the model of the steering device for calculating the change rate dDE of driving energy. It is a figure which shows an example of the change of dPS of driving energy, and the change of the work rate PS of patent document 1 about the condition where a steering direction reverses. It is a figure which shows an example of the change of dPS of driving energy, and the change of the work rate PS of patent document 1 about the condition where hand-off was performed in the second half of reciprocating steering. It is a figure which shows an example of the change rate dDE (upper stage) and index value Iin (lower stage) of driving energy. It is a figure which shows the other example of the change of the change rate dDE (upper stage) of driving energy, and index value Iin (lower stage). It is a figure which shows the relationship between the steering angle (theta) in a certain vehicle speed, and the control electric current Ic to an electric power steering apparatus, and its tolerance | permissible_range.

[First embodiment]
FIG. 1 is an explanatory diagram showing an outline of a first embodiment of a steering assist device 10 for a vehicle according to the present invention. The steering assist device 10 of this embodiment is applied to a vehicle 14 on which a column assist type electric power steering device (EPS) 12 is mounted. The electric power steering device may be another type of power steering device as long as the assist torque can be controlled, for example, a rack coaxial type rack-assisted electric power steering device.

  In FIG. 1, a vehicle 14 includes a steering device 16 that is a steering system of the vehicle. The steering device 16 transmits steering force and displacement between the steering wheel 18 operated by the driver, the left and right front wheels 20L and 20R which are steering wheels, and the steering wheel 18 and the front wheels 20L and 20R. Device 22. The transmission device 22 includes an upper steering shaft 24 that rotates together with the steering wheel 18, an intermediate shaft 26, and a steering mechanism 28. The intermediate shaft 26 is connected to the lower end of the upper steering shaft 24 via the universal joint 30 at the upper end and is connected to the pinion shaft 34 of the steering mechanism 28 via the universal joint 32 at the lower end.

  The steering mechanism 28 includes a rack-and-pinion type steering unit 36 and tie rods 38L and 38R. The steering unit 36 converts the rotation of the pinion shaft 34 into a linear movement of the rack bar 40 in the lateral direction of the vehicle, and The reverse conversion is performed. The tie rods 38L and 38R are pivotally attached to the tip of the rack bar 40 at the inner ends, and the outer ends of the tie rods 38L and 38R are knuckle arms 42L provided on carriers (not shown) of the left and right front wheels 20L and 20R. And 42R.

  Therefore, the rotational displacement and rotational torque of the steering wheel 18 are converted by the transmission device 22 into swinging and rotational torque around the kingpin shaft (not shown) of the front wheels 20L and 20R and transmitted to the front wheels 20L and 20R. . Further, the swing and rotational torque around the kingpin shaft received by the left and right front wheels 20L and 20R from the road surface 44 are transmitted to the steering wheel 18 by the transmission device 22 as rotational displacement and rotational torque, respectively.

  The steering assist device 10 includes an electric power steering device 12. The power steering device 12 includes an electric motor 46 and a conversion device 48, which are not shown in FIG. 1, but the conversion device 48 is a worm gear fixed to the rotating shaft of the electric motor 46 and a worm fixed to the upper steering shaft 24. Includes a wheel. The rotational torque of the electric motor 46 is converted into rotational torque around the upper steering shaft 24 by the conversion device 48 and transmitted to the upper steering shaft. Therefore, the power steering device 12 functions as an adjustment force applying device that applies an assist torque as an adjustment force for adjusting a force related to steering to the upper steering shaft 24 of the transmission device 2.

  Further, the steering assist device 10 has an electronic control device 50. The electronic control device 50 functions as a control device that controls the assist torque applied to the upper steering shaft 24 by the power steering device 12 by controlling the rotational torque of the electric motor 46, as will be described in detail later. The electronic control unit 50 receives signals indicating the steering angle θ and the steering torque T from a steering angle sensor 52 and a torque sensor 54 provided on the upper steering shaft 24, respectively. The electronic control device 50 also receives a signal indicating the vehicle speed V from the vehicle speed sensor 56.

  The electronic control device 50 includes a CPU, a ROM, a RAM, and an input / output port device, which are connected to each other via a bidirectional common bus. The ROM stores a control program, a map, and the like, which will be described later. You may remember. Further, the steering angle sensor 52 and the torque sensor 54 detect the steering angle θ and the steering torque Ts, respectively, with the case of steering in the left turn direction of the vehicle as positive.

  The microcomputer of the electronic control unit 50 calculates the assist torque for calculating the target assist torque Tat according to the block diagram shown in FIG. 2 and the flowchart shown in FIG. 3 based on the steering angle θ, the steering torque T, and the vehicle speed V. It functions as the device 62.

  First, the block diagram shown in FIG. 2 will be described. In addition, the figure in each block shown by FIG. 2 has shown roughly the map used for the calculation in a corresponding block.

  The assist torque calculation device 62 calculates the target assist torque Tat as the sum of the basic assist torque, the damping control amount, the friction control amount, and the return control amount for returning the steering wheel 18 to the neutral position. The assist torque calculation device 62 includes a basic assist torque calculation block 64, a damping control amount calculation block 66, a friction control amount calculation block 68, and a return control amount calculation block 70. Further, the assist torque calculation device 62 includes an attenuation control amount gain calculation block 72, a friction control amount gain calculation block 74, and a return control amount gain calculation block 76.

  The basic assist torque calculation block 64 calculates the basic assist torque Tab based on the steering torque T and the vehicle speed V so that the magnitude increases as the steering torque T increases and decreases as the vehicle speed V increases. A signal indicating the basic assist torque Tab is output to the multiplier 78.

  The damping control amount calculation block 66 calculates the damping control amount Td based on the steering angle differential value dθ such that the larger the steering angle θ differential value (steering angular velocity) dθ, the larger the magnitude. The attenuation control amount gain calculation block 72 performs the attenuation control based on the vehicle speed V so that the attenuation control amount gain Kd is smaller in the low speed range than in the very low speed range, and increases in the medium and high speed range as the vehicle speed V is higher. The quantity gain Kd is calculated. The signal indicating the attenuation control amount Td and the signal indicating the attenuation control amount gain Kd are output to the multiplier 80, and the product Td · Kd of the attenuation control amount Td calculated by the multiplier 80 and the attenuation control amount gain Kd. Is output to the multiplier 82 as the corrected attenuation control amount Tda.

  A signal indicating the friction torque Tf calculated by the friction torque calculation block 84 based on the steering torque T and a signal indicating the steering angle θ are input to the friction control amount calculation block 68. The friction control amount calculation block 68 calculates a basic friction control amount Tfb based on the friction torque Tf and the steering angle θ. The friction control amount gain calculation block 74 calculates the friction control amount gain Kf based on the vehicle speed V so that the friction control amount gain calculation block 74 increases as the vehicle speed V increases in the low and medium speed ranges and becomes a constant value in the high speed range. To do. A signal indicating the basic friction control amount Tfb and a signal indicating the friction control amount gain Kf are output to the multiplier 86, and the product Tfb of the basic friction control amount Tfb calculated by the multiplier 86 and the friction control amount gain Kf is obtained. A signal indicating Kf is output to the multiplier 88 as the corrected friction control amount Tfa.

  The friction torque Tf is a torque that acts as a frictional drag against the driver's steering operation, and may be calculated, for example, in the manner described in Japanese Patent Application Laid-Open No. 2009-126244 related to the application of the present applicant.

  The return control amount calculation block 70 receives a signal indicating the steering angular velocity deviation Δdθ. The steering angular velocity deviation Δdθ is calculated by subtracting the steering angular velocity dθ by the adder 92 from the target steering angular velocity dθt calculated by the target steering angular velocity calculation block 90 based on the steering angle θ. The return control amount calculation block 70 calculates the return control amount Tr based on the steering angular velocity deviation Δdθ so that the larger the steering angular velocity deviation Δdθ is, the larger the magnitude is. The return control amount gain calculation block 76 calculates the return control amount gain Kr based on the vehicle speed V so that it becomes smaller as the vehicle speed V is higher in the low and medium speed ranges and becomes a constant value in the high speed range. To do. A signal indicating the return control amount Tr and a signal indicating the return control amount gain Kr are output to the multiplier 94, and the product Tr · Kr of the return control amount Tr calculated by the multiplier 94 and the return control amount gain Kr. Is output to the multiplier 96 as a corrected return control amount Tra.

  In FIG. 2, the map of the blocks 64, 66, 70, 84 and 90 shows the values such as the basic assist torque Tab to be calculated only when the variable steering torque T is a positive value. Not. However, the value to be calculated when the variable is a negative value is a value that is point-symmetric with respect to the origin.

  Furthermore, the assist torque calculation device 62 has a correction gain calculation block 98 that calculates a change rate dDE of driving energy for the steering device 16 and calculates a correction gain for the basic assist torque Tab and the like based on the change rate dDE. . The change rate dDE of the driving energy is a value calculated based on the model 100 of the steering device 16 (steering system) shown in FIG.

  As shown in FIG. 7, in the model 100, the driver's hand 102 and the rigid steering wheel 18 are referred to as a steering wheel 18 '. Further, it is assumed that the mass of the main movable member of the steering device 16 is concentrated on the steering wheel 18 ′ and the inertia yaw moment of the steering wheel 18 ′ is I. Further, it is assumed that the steering device 16 excluding the steering wheel 18 is an elastic body having a torsional deformation spring constant k and having no mass.

The driving energy DE of the model 100, which is the energy held by the model 100, is assumed to be the sum of rotational energy and elastic energy corresponding to the internal energy and PV work in the enthalpy theory of thermodynamics, respectively. Therefore, the driving energy DE of the model 100 is expressed by the following equation (1), where dθ is a differential value of the steering angle θ that is the rotation angle of the steering wheel 18 ′.

Assuming that the torque generated when the upper end of the transmission device 22, that is, the end on the steering wheel 18 ′ side is rotated by the angle θ by the force from the steering wheel side is Tsat, the torque Tsat is expressed by the following equation (2). expressed.
Tsat = −k · θ (2)

Therefore, from the above formulas (1) and (2), the driving energy DE of the model 100 is represented by the following formula (3).

The inflow of energy into the model 100 and the outflow of energy from the model 100, that is, the change in the driving energy DE of the model 100 can be determined by the sign of the differential value. By differentiating the above equation (3), the differential value of the driving energy DE, that is, the change rate dDE is expressed by the following equation (4).

Since the sign of the steering torque T is opposite to the sign of the torque Tsat and −Tsat = T, when the differential value of the steering torque T is dT, the above equation (4) is rewritten as the following equation (5): Can do. The first term, the second term, and the third term in the following formula (5) are referred to as the P0 term, the P1 term, and the P2 term, respectively, as necessary.

  The correction gain calculation block 98 calculates the correction gain for each control amount according to the flowchart shown in FIG. In addition, the figure in the frame of each step shown in FIG. 3 schematically shows a map used for calculation in the corresponding step. Further, the control according to the flowchart shown in FIG. 3 is repeatedly executed by the electronic control unit 50 at predetermined time intervals when an ignition switch not shown in FIG. 1 is on. This also applies to the control according to the flowcharts shown in FIGS. 5 and 6 in the second embodiment described later.

  First, at step 10, a signal indicating the steering angle θ detected by the steering angle sensor 52 is read, and at step 20, the differential value dθ of the steering angle θ, the second-order differential value ddθ of the steering angle θ, and the steering torque. A differential value dT of T is calculated. The steering angle differential value dθ may be a value detected as the steering angular velocity, and the second-order differential value ddθ of the steering angle may be calculated as a differential value of the detected steering angular velocity dθ.

  In step 30, the change rate dDE of the driving energy DE is calculated according to the above equation (5). Note that the inertia yaw moment I in the calculation of the change rate dDE may not be a value that takes into account the mass of all the movable members of the driver's hand and the steering device 16. For example, the inertia yaw moment I is a value based on the mass of the driver's hand and the steering wheel 18 and a value based on the mass of the driver's hand, the steering wheel 18 and the rotating member (the upper steering shaft 24, the intermediate shaft 26, etc.). And so on.

  In step 40, the rate of change dDE of the driving energy DE is subjected to low-pass filter processing, whereby the rate of change dDEf of driving energy after low-pass filter processing from which high-frequency noise components have been removed is calculated.

  In step 50, a basic gain Kabb for the basic assist torque Tab is calculated based on the driving energy change rate dDEf after the low-pass filter processing. In this case, when the change rate dDEf is a positive value, the basic gain Kabb is calculated to a positive value (1 or less) that increases as the change rate dDEf increases. On the contrary, when the change rate dDEf is equal to or less than a preset negative reference value, the basic gain Kabb is calculated to a negative value (−1 or more) whose absolute value increases as the change rate dDEf decreases. Further, when the change rate dDEf is greater than the negative reference value and equal to or less than 0, the basic gain Kabb is calculated to increase as the change rate dDEf increases.

  The basic gain Kabb may be calculated to a positive constant value of 1 or less when the change rate dDEf is a positive value. Further, the basic gain Kabb may be calculated to a negative constant value of −1 or more when the rate of change dDEf is equal to or less than a preset negative reference value.

  In step 60, the vehicle speed gain Kvab for the basic assist torque Tab is calculated based on the vehicle speed V to a positive value (1 or less) that decreases as the vehicle speed V increases.

  In step 70, the correction gain Kab for the basic assist torque Tab is calculated as the sum of the product of the basic gain Kabb and the vehicle speed gain Kvab and 1 (Kabb · Kvab + 1).

  In step 80, the basic gain Kdab for the corrected attenuation control amount Tda is calculated based on the change rate dDEf of the driving energy after the low-pass filter processing. In this case, when the change rate dDEf is a positive value, the basic gain Kdab is calculated to a negative value (−1 or more) whose absolute value increases as the change rate dDEf increases. Conversely, when the rate of change dDEf is equal to or less than a preset negative reference value, the basic gain Kdab is calculated to a positive value (1 or less) that increases as the rate of change dDEf decreases. Further, when the change rate dDEf is greater than the negative reference value and equal to or less than 0, the basic gain Kdab is calculated to decrease as the change rate dDEf increases.

  In step 90, the vehicle speed gain Kvda for the corrected damping control amount Tda is calculated based on the vehicle speed V to a positive value (1 or less) that increases as the vehicle speed V increases.

  In step 100, the correction gain Kda for the corrected damping control amount Tda is calculated as the sum of the product of the basic gain Kdab and the vehicle speed gain Kvda and 1 (Kdab · Kvda + 1).

  In step 110, a basic gain Kfab for the corrected friction control amount Tfa is calculated based on the driving energy change rate dDEf after the low-pass filter processing. In this case, when the change rate dDEf is a positive value, the basic gain Kfab is calculated to a negative value (−1 or more) whose absolute value increases as the change rate dDEf increases. On the other hand, when the change rate dDEf is equal to or less than a preset negative reference value, the basic gain Kfab is calculated to a positive value (1 or less) that increases as the change rate dDEf decreases. Further, when the change rate dDEf is greater than the negative reference value and equal to or less than 0, the basic gain Kfab is calculated to decrease as the change rate dDEf increases.

  In step 120, the vehicle speed gain Kvfa for the corrected friction control amount Tfa is calculated based on the vehicle speed V to a positive value (1 or less) that increases as the vehicle speed V increases.

  In step 130, the correction gain Kfa for the corrected friction control amount Tfa is calculated as the sum of the product of the basic gain Kfab and the vehicle speed gain Kvfa and 1 (Kfab · Kvfa + 1).

  In addition, the matter relevant to the calculation in the above steps 50-130 is described in the international publication of the above-mentioned patent document 1.

  In step 140, the basic gain Krab for the corrected return control amount Tra is calculated based on the change rate dDEf of the driving energy after the low-pass filter processing. In this case, when the change rate dDEf is a positive value, the basic gain Krab is calculated to a negative value (−1 or more) whose absolute value increases as the change rate dDEf increases. Conversely, when the change rate dDEf is equal to or less than a preset negative reference value, the basic gain Krab is calculated to a positive value (1 or less) that increases as the change rate dDEf decreases. Further, when the change rate dDEf is greater than the negative reference value and equal to or less than 0, the basic gain Krab is calculated to decrease as the change rate dDEf increases.

  The basic gains Kdab, Kfab, and Krab may be calculated as negative constant values of −1 or more when the change rate dDEf is a positive value. Further, the basic gains Kdab, Kfab, and Krab may be calculated to be positive constant values of 1 or less when the change rate dDEf is less than or equal to a preset negative reference value.

  In step 150, the vehicle speed gain Kvra for the corrected return control amount Tra is calculated to a positive constant value (1 or less) regardless of the vehicle speed V. The vehicle speed gain Kvra may be calculated to a positive value (1 or less) that increases slightly as the vehicle speed V increases.

  In step 160, the correction gain Kra for the corrected return control amount Tra is calculated as the product Krab · Kvra of the basic gain Krab and the vehicle speed gain Kvra.

  In addition, the matter relevant to the calculation in the above steps 140-160 is described in Unexamined-Japanese-Patent No. 2014-148178 concerning the application of this applicant.

  Returning to FIG. 2, the correction gains Kab, Kda, Kfa and Kra calculated in the correction gain calculation block 98 as described above are output to the multipliers 78, 82, 88 and 96, respectively. An output from the multiplier 78, that is, a signal indicating a product Tab · Kab of the basic assist torque Tab and the correction gain Kab is input to the adder 106.

  An output from the multiplier 82, that is, a signal indicating the product Tda · Kda of the corrected attenuation control amount Tda and the correction gain Kda is also input to the adder 106. The output of the adder 106, that is, a signal indicating the sum of the product Tab · Kab and the product Tda · Kda (Tab · Kab + Tda · Kda) is input to the adder 108.

  An output from the multiplier 88, that is, a signal indicating the product Tfa · Kfa of the corrected friction control amount Tfa and the correction gain Kfa is also input to the adder. The output of the adder 108, that is, a signal indicating the sum of the products Tab · Kab, Tda · Kda and Tfa · Kfa (Tab · Kab + Tda · Kda + Tfa · Kfa) is input to the adder 110.

  The output of the multiplier 96, that is, a signal indicating the product Tra · Kra of the corrected return control amount Tra and the correction gain Kra is also input to the adder 110. The output of the adder 110, that is, a signal indicating the sum of the products Tab · Kab, Tda · Kda, Tfa · Kfa and Tra · Kra (Tab · Kab + Tda · Kda + Tfa · Kfa + Tra · Kra) is used to control the power steering device 12. It is used as a signal indicating the target assist torque Tat.

  As can be seen from the above description, the target assist torque Tat returns the basic assist torque (Tab · Kab), the damping control amount (Tda · Kda), the friction control amount (Tfa · Kfa), and the steering wheel 18 to the neutral position. Is calculated as the sum of the return control amounts (Tra · Kra). Then, the gains Kab, Kda, Kfa, and Kra of the control amounts are variably controlled based on the driving energy change rate dDE according to the flowchart shown in FIG.

  In particular, in steps 20 and 30, a driving energy change rate dDE is calculated, and in step 40, a driving energy change rate dDEf from which high-frequency noise components have been removed by low-pass filtering is calculated. Then, based on the change rate dDEf of the driving energy after the low-pass filter processing, the basic gains Kabb, Kdab, Kfab and Krab are calculated in steps 50, 80, 110, and 140, so that each basic gain is changed to the change rate dDEf. It is variably set according to the sign and size. Therefore, the correction amount of each component (basic assist torque, damping control amount, friction control amount, and return control amount) of the target assist torque Tat as the adjustment force can be appropriately changed.

  The torque that is reversely input from the road surface to the steering device 16 via the steering wheel is generally small. Therefore, when the rate of change dDEf is positive and large, that is, when the rate of change dDEf is large at the rate of increase, the energy is generated by the driver's steering. This is considered to be a situation of positive input given to the steering device 16.

  According to the control of each gain performed according to the flowchart shown in FIG. 3, the basic assist torque Tab is increased as the change rate dDEf is positive and larger, and the damping control amount Tda, the friction control amount Tfa, and the return control amount Tra are set. Can be small. Therefore, it is possible to assist the driver's steering and to reduce the steering resistance caused by the damping control torque, the friction control torque, and the return torque to the neutral position, so that the driver can easily perform the steering operation. Can do.

  In the situation where the steering wheel 18 is controlled to return to the neutral position by the return control amount Tra, if the driver steers in the neutral position direction, the change rate dDEf is determined to be positive, and in that case Also, the return control amount Tra is reduced, and the assist torque is reduced. Therefore, in this situation, the return control amount Tra is not reduced, but is controlled to the same value as when the rate of change dDEf is negative or 0, so that the driver steers in the neutral position direction. It may be easier to do.

  Conversely, when the rate of change dDEf is a negative value and the absolute value is large, that is, when the rate of change dDEf is a decreasing rate of change and the absolute value is large, the energy given to the steering device 16 by the driver's steering is 0 or small. This value is considered to be a large reverse input situation that is input from the road surface to the steering device 16 via the steering wheel.

  According to the control of each gain performed in accordance with the flowchart shown in FIG. 3, the basic assist torque Tab is decreased as the change rate dDEf is a negative value and the absolute value is large, and the damping control amount Tda, the friction control amount Tfa, and The return control amount Tra can be increased. Therefore, since the steering resistance can be increased without unnecessarily assisting the driver's steering, the degree to which the steering wheel 18 is rotationally driven due to the disturbance is reduced, and the steering stability is improved. be able to.

  Since the change rate dDEf of the driving energy includes the P0 term related to the product of the steering angular velocity and the differential value of the steering angular velocity, the driving energy change rate dDEf is relatively large even when steering is performed in a situation where the steering wheel 18 is in the neutral range. Change. Therefore, as compared with the determination based on the index value that does not include the P0 term, in the situation where the steering wheel is in the neutral range, the change in the steering condition is determined earlier, and thereby the basic assist torque Tab or the like is determined earlier. Increase / decrease control can be performed.

  For example, FIG. 8 shows an example of the change in the work energy PS described in the above-mentioned Patent Document 1, which is the sum of the change rate dDE of driving energy and the terms P1 and P2 in a situation where the steering direction is reversed. It can be seen that the change rate dDE changes from a negative value to a positive value at a time point t1 earlier than a time point t2 when the work rate PS changes from a negative value to a positive value.

  Further, FIG. 9 shows an example of the change rate dDE of the driving energy and the change of the work rate PS described in Patent Document 1 in the situation where the hand is released in the second half of the reciprocating steering. The work rate PS remains negative after the time t3 when the hand is released, whereas the change rate dDE of the driving energy is a negative value immediately after the time t3, but once becomes a positive value. Then, it becomes negative again. This phenomenon is that immediately after the release of the hand, the steering wheel 18 rotates and energy is given to the steering device 16, whereby the rate of change dDE once becomes a positive value, but changes due to the reaction of the positive input of the energy. It is thought that this is because the rate dDE becomes a negative value again.

  According to the first embodiment, the rotational behavior of the steering wheel 18 can be determined based on the fluctuation of the rate of change dDE in the latter half of the reciprocating steering. Therefore, it is possible to appropriately perform increase / decrease control of the basic assist torque Tab or the like in accordance with the rotational behavior of the steering wheel 18 in the situation where the hand is released without requiring the hand release determination.

  Further, when the steering wheel 18 is rotated in the same direction by the positive input and the reverse input, the steering torque and the rate of change thereof are only small values. Therefore, this situation cannot be determined depending on the work rate PS. However, even in this situation, the steering wheel rotates, so that the steering angle θ changes, and the steering angular velocity dθ and its differential value ddθ change relatively large. Therefore, since the change rate dDE of the driving energy can also determine this situation, even when the positive input and the reverse input to the steering system are in phase, the basic assist torque Tab or the like according to the change rate dDE. Increase / decrease control can be performed appropriately. In addition, the above effect is acquired similarly also in 2nd embodiment mentioned later.

[Second Embodiment]
FIG. 4 is a block diagram of an assist torque calculating device 62 for calculating the assist torque Ta in the second embodiment of the vehicle steering assist device 10 according to the present invention. In FIG. 4, the same parts as those shown in FIG. 2 are denoted by the same reference numerals as those in FIG.

  In the first embodiment, when the reverse input torque is large, the reverse input is determined, and the assist torque can be controlled accordingly. However, even if reverse input occurs, if the torque is small, it is not possible to determine reverse input, and therefore it is not possible to control assist torque according to the reverse input.

  In the second embodiment, as an index value Iin for determining whether the input to the steering device 16 is a positive input or a reverse input, the product dT · T of the steering torque T and its differential value dT, and the driving energy The product dT · T · dDE with the change rate dDE is calculated. When the input is a positive input, the product dT · T changes in phase with the driving energy change rate dDE, but when the input is a reverse input, the product dT · T has a phase opposite to the driving energy change rate dDE. Will change. Therefore, the index value Iin is an index value indicating the ratio of the positive input and the reverse input with respect to the total input to the steering device 16, and the higher the ratio of the positive input with respect to the total input, the larger the index value Iin is. Conversely, the higher the ratio of the reverse input to the total input, the negative the index value Iin and the larger the absolute value.

  For example, when the change rate dDE of the driving energy changes as shown in the upper part of FIGS. 10 and 11, the index value Iin changes as shown in the lower part of FIGS. Think.

  The region A is a region where both the change rate dDE and the index value Iin are positive, and the region B is a region where the change rate dDE is negative and the index value Iin is positive. A region C is a region where the change rate dDE is positive and the index value Iin is negative, and a region D is a region where both the change rate dDE and the index value Iin are negative.

The characteristics required for the steering device 16 in the areas A to D are as shown in Table 1 below. Region A is a region where steering responsiveness should be emphasized, and region B is a region where steering stability should be emphasized. Region C is a region where the degree of emphasis on steering response should be reduced as compared to region A. The region C is a region in which the degree of emphasis on responsiveness should be reduced and corrected as compared with the region A so as to achieve original responsiveness. The region D is a region in which the steering response is more important than the region B. Further, the required characteristics common to the areas A and B are steering characteristics that match the steering operation of the driver, and the required characteristics common to the areas C and D are characteristics that reduce the burden on the driver due to disturbance. is there.

  In this embodiment, blocks other than the correction gain calculation block 98 of the assist torque calculation device 62 function in the same manner as the corresponding blocks in the first embodiment. The correction gain calculation block 98 is based on the basic assist torque Tab, the corrected damping control amount Tda, the corrected friction control amount Tfa, and the corrected return control amount in accordance with the flowcharts shown in FIGS. The correction gains Kaba, Kdaa, Kfaa and Kraa for Tra are calculated. The correction gains Kaba, Kdaa, Kfaa and Kraa are output to the multipliers 78, 82, 86 and 96, respectively.

  Steps 10 to 160 in the flowchart shown in FIG. 3 are executed in the same manner as in the first embodiment, and steps 210 to 420 in the flowchart shown in FIGS. 5 and 6 are executed following step 160. Is done.

  In step 210, a signal indicating the steering torque T detected by the steering torque sensor 54 is read, and in step 220, a differential value dT of the steering torque T is calculated.

  In step 230, the product dT · T of the steering torque T and its differential value dT is calculated, and the product dT · Tf is low pass filtered to calculate the product dT · Tf after the low pass filter processing. The

  In step 240, an index value Iin for determining the input direction is calculated as a product dT · Tf · dDEf of the product dT · Tf after the low-pass filter processing and the driving energy change rate dDEf after the low-pass filter processing.

  In step 270, a basic gain Kiabb for the basic assist torque Tab is calculated based on the index value Iin for determining the input direction. In this case, when the index value Iin is a positive value, the basic gain Kiabb is calculated to a positive value (1 or less) that increases as the index value Iin increases. Conversely, when the index value Iin is equal to or less than a preset negative reference value, the basic gain Kiabb is calculated to a positive value (a value close to 0) whose absolute value decreases as the index value Iin decreases. Further, when the index value Iin is greater than the negative reference value and equal to or less than 0, the basic gain Kiabb is calculated to increase as the index value Iin increases.

  The basic gain Kiabb may be calculated to a positive constant value of 1 or less when the index value Iin is a positive value. Further, the basic gain Kiabb may be calculated to a positive constant value close to 0 when the index value Iin is equal to or less than a preset negative reference value.

  In step 280, the vehicle speed gain Kviab for the basic assist torque Tab is calculated based on the vehicle speed V to a positive value (1 or less) that decreases as the vehicle speed V increases.

  In step 290, the correction gain Kiab for the basic assist torque Tab is calculated as the product (Kiabb · Kviab) of the basic gain Kiabb and the vehicle speed gain Kviab.

  In step 300, the corrected correction gain Kaba for the basic assist torque Tab is calculated as the sum (Kab + Kiab) of the correction gain Kab calculated in step 70 and the correction gain Kiab calculated in step 290.

  In step 310, the basic gain Kidab for the corrected attenuation control amount Tda is calculated based on the index value Iin for determining the input direction. In this case, when the index value Iin is a positive value, the basic gain Kidab is calculated to a positive value (a value close to 0) that decreases as the index value Iin increases. On the other hand, when the index value Iin is equal to or less than a preset negative reference value, the basic gain Kidab is calculated to a positive value (1 or less) that increases as the index value Iin decreases. Further, when the index value Iin is greater than the negative reference value and equal to or less than 0, the basic gain Kidab is calculated to decrease as the index value Iin increases.

  In step 320, the vehicle speed gain Kvida for the corrected damping control amount Tda is calculated based on the vehicle speed V to a positive value (1 or less) that increases as the vehicle speed V increases.

  In step 330, the correction gain Kida for the corrected damping control amount Tda is calculated as the product (Kidab · Kvida) of the basic gain Kidab and the vehicle speed gain Kvida.

  In step 340, the corrected correction gain Kdaa for the corrected attenuation control amount Tda is calculated as the sum (Kda + Kida) of the correction gain Kda calculated in step 100 and the correction gain Kida calculated in step 330. Is done.

  In step 350, a basic gain Kifab for the corrected friction control amount Tfa is calculated based on the index value Iin for determining the input direction. In this case, when the index value Iin is a positive value, the basic gain Kifab is calculated to a positive value (a value close to 0) that decreases as the index value Iin increases. On the other hand, when the index value Iin is equal to or smaller than a preset negative reference value, the basic gain Kifab is calculated to a positive value (1 or less) that increases as the index value Iin decreases. Further, when the index value Iin is larger than the negative reference value and equal to or less than 0, the basic gain Kifab is calculated to decrease as the index value Iin increases.

  In step 360, the vehicle speed gain Kvifa for the corrected friction control amount Tfa is calculated based on the vehicle speed V to a positive value (1 or less) that increases as the vehicle speed V increases.

  In step 370, the correction gain Kifa for the corrected friction control amount Tfa is calculated as the product (Kifab · Kvifa) of the basic gain Kifab and the vehicle speed gain Kvifa.

  In step 380, the corrected correction gain Kfaa for the corrected friction control amount Tfa is calculated as the sum (Kfa + Kifa) of the correction gain Kfa calculated in step 130 and the correction gain Kifa calculated in step 370. Is done.

  In step 390, a basic gain Kirab for the corrected return control amount Tra is calculated based on the index value Iin for determining the input direction. In this case, when the index value Iin is a positive value, the basic gain Kirab is calculated to a positive value (a value close to 0) that decreases as the index value Iin increases. On the other hand, when the index value Iin is equal to or less than a preset negative reference value, the basic gain Kirab is calculated to a positive value (1 or less) that increases as the index value Iin decreases. Further, when the index value Iin is greater than the negative reference value and equal to or less than 0, the basic gain Kirab is calculated to decrease as the index value Iin increases.

  In step 400, the vehicle speed gain Kvira for the corrected return control amount Tra is calculated based on the vehicle speed V to a positive value (1 or less) that increases as the vehicle speed V increases.

  In step 410, the correction gain Kira for the corrected return control amount Tra is calculated as the product (Kirab · Kvira) of the basic gain Kirab and the vehicle speed gain Kiravi.

  In step 420, the corrected correction gain Kraa for the corrected return control amount Tra is calculated as the sum (Kra + Kira) of the correction gain Kra calculated in step 160 and the correction gain Kira calculated in step 410. Is done.

  Note that the basic gains Kidab, Kifab, and Kirab may be calculated as constant positive values close to 0 when the index value Iin is a positive value. Further, the basic gains Kidab, Kifab, and Kirab may be calculated as positive constant values of 1 or less when the index value Iin is less than or equal to a preset negative reference value.

  As can be understood from the above description, according to the second embodiment, the index value Iin for determining whether the input to the steering device 16 is a positive input or a reverse input is calculated. The correction gains Kab, Kda, Kfa, and Kra are not only variably controlled according to the driving energy change rate dDEf, but also variably controlled according to the index value Iin, as in the first embodiment. Therefore, as shown in Table 1 above, it is possible to determine the regions A to D according to the sign of the change rate dDEf and the index value Iin, and to control the assist torque Ta so as to have characteristics suitable for the region. .

  That is, according to the second embodiment, the magnitude of the basic assist torque or the like is based on both the result of the input situation determination based on the driving energy change rate dDEf and the result of the input situation determination based on the index value Iin. Can be controlled. Therefore, compared with the case of the first embodiment in which the magnitude of the basic assist torque or the like is controlled based only on the determination result of the input situation based on the change rate dDEf of the driving energy, the basic is determined according to the actual input situation. The assist torque and the like can be controlled more preferably.

  In particular, in the region A, the magnitude of the basic assist torque (Tab · Kab) is increased so that a characteristic in which the driver's steering response is emphasized is obtained. In the region B, the damping control amount (Tda · Kda) and the friction control are performed so that the degree of rotation of the steering wheel 18 due to the disturbance from the road surface is reduced and a characteristic in which the steering stability is emphasized is obtained. The magnitudes of the amount (Tfa · Kfa) and the return control amount (Tra · Kra) are increased. In the region C, the amount of increase in the magnitude of the basic assist torque Tab is reduced as compared with the region A so that the steering response by the driver does not become excessive. Further, in the region D, the amount of increase of the damping control amount, the friction control amount, and the return control amount is increased as compared with the region B so that a characteristic in which the steering stability is further emphasized can be obtained. .

  Furthermore, according to the second embodiment, the index value Iin is calculated as the product dT · T · dDE of the product dT · T of the steering torque T and its differential value dT and the change rate dDE of the driving energy. . Therefore, using the rate of change dDE of the steering system energy, the steering torque T used for the calculation thereof, and the differential value dT of the steering torque, whether the energy input status to the steering system is a positive input status or vice versa. It can be determined whether or not the input state. Further, a special device for determining the input direction such as two torque sensors is not necessary.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to the above-described embodiments, and various other embodiments are possible within the scope of the present invention. This will be apparent to those skilled in the art.

  For example, in each of the above-described embodiments, the rate of change of the steering system energy is the differential value dDE of the driving energy DE that is the energy of the steering system, but the difference in the driving energy DE calculated every predetermined time ( Time differential value).

  In each of the above-described embodiments, the target assist torque Tat includes the basic assist torque (Tab · Kab), the damping control amount (Tda · Kda), the friction control amount (Tfa · Kfa), and the steering wheel 18 in the neutral position. It is calculated as the sum of the return control amount (Tra · Kra) for returning to. However, at least one of the damping control amount, the friction control amount, and the return control amount may be corrected so as not to be corrected according to the change rate dDEf of the driving energy DE.

  In the second embodiment described above, in order to determine whether the input to the steering device 16 is a positive input or a reverse input, the product of the steering torque T and its differential value dT and the change rate dDE of the driving energy. The index value Iin for determining the input direction is calculated from the product dT · T · dDE. However, the determination of the input direction may be performed by other means.

  For example, the relationship between the steering angle θ at a certain vehicle speed and the control current Ic to the electric power steering device 12 is the relationship indicated by the solid line in FIG. 12, and the allowable range is the range indicated by hatching. Suppose there is. When the relationship between the steering angle θ and the control current Ic is within the range indicated by hatching, it is determined that the situation is a positive input (reverse input is small), and the relationship between the steering angle θ and the control current Ic is When it is outside the range indicated by hatching, it may be determined that the situation is reverse input.

  Further, for example, two torque sensors are provided at positions spaced apart in the extending direction of the upper steering shaft 24, and the input to the steering device 16 is a positive input or a reverse input depending on a phase difference between detection values of the two torque sensors. May be determined.

  Further, the sign of the product dT · T · dPS of the product of the steering torque T and its differential value dT and the change rate of the work rate PS with dPS, where dPS is the change rate of the work rate PS described in Patent Document 1 above. The input direction may be determined based on. The index value Iin has a larger range of variation than the product dT, T, and dPS. Therefore, the index value Iin makes the input direction appropriate even when the input direction changes frequently, especially when driving on rough roads. Can be determined.

DESCRIPTION OF SYMBOLS 10 ... Steering assistance device, 12 ... Electric power steering device (EPS), 14 ... Vehicle, 16 ... Steering device, 18 ... Steering wheel, 20L, 20R ... Front wheel, 22 ... Transmission device, 50 ... Electronic control device, 52 ... Steering angle sensor 54 ... Torque sensor 56 ... Vehicle speed sensor 62 ... Assist torque calculation device

Claims (7)

Applied to a vehicle including a steering device including a steering wheel operated by a driver, a steering wheel, and a transmission device that transmits a force and displacement related to steering between the steering wheel and the steering wheel; A steering assist for a vehicle, comprising: an adjustment force applying device that applies an adjustment force that adjusts a force related to steering to the transmission device; and a control device that controls the adjustment force that the adjustment force application device applies to the transmission device In the device
A steering angle detection device for detecting the steering angle;
A steering torque detection device for detecting steering torque,
The control device acquires a steering angular velocity, a differential value of the steering angular velocity, and a differential value of the steering torque, and uses the steering wheel, the transmission device, the adjustment force applying device, and the steering wheel as a steering system, and the steering angular velocity and the steering angular velocity. The rate of change in the energy of the steering system is calculated based on the product of the differential value of the steering angle, the product of the steering angular velocity and the steering torque, and the product of the differential value of the steering angle and the steering torque. Controlling the adjustment force based on a rate;
A steering assist device for a vehicle.   2. The vehicle steering assist device according to claim 1, wherein the control device is a movable member constituting the steering system and includes an inertia yaw moment, a steering angular velocity, and a steering angular velocity based on a mass of the movable member including at least the steering wheel. Steering support for a vehicle that calculates the product of the differential value of the steering angle, the product of the steering angular velocity and the steering torque, and the sum of the product of the steering angle and the differential value of the steering torque as the rate of change of the energy of the steering system apparatus. In the vehicle steering assist device according to claim 1 or 2,
The adjustment force is a steering assist force,
The control device increases the steering assist force when the rate of change of the energy of the steering system is an increase rate of change compared to when the rate of change of the energy of the steering system is not an increase rate of change. ,
A steering assist device for a vehicle. In the vehicle steering assist device according to claim 1 or 2,
The adjusting force is at least one of a steering damping force and a steering friction force,
When the rate of change in the energy of the steering system is a rate of change in the steering system, the control device compares the steering damping force and the steering in comparison with when the rate of change in the energy of the steering system is not a rate of change in the decrease. Increase at least one of the frictional forces,
A steering assist device for a vehicle.   4. The steering assist device for a vehicle according to claim 3, wherein the control device is configured such that an input state of energy to the steering system is a positive input state by a driver's steering, or the steering wheel applies a force from a road surface. It is determined whether the situation is a reverse input by receiving, and the magnitude of the correction amount of the steering assist force in the reverse input situation is the magnitude of the correction amount of the steering assist force in the positive input situation. A steering assist device for a vehicle that changes the amount of correction of the steering assist force so as to be smaller than that of the vehicle.   5. The vehicle steering assist device according to claim 4, wherein the control device is configured such that an input state of energy to the steering system is a positive input state by a driver's steering, or the steering wheel applies a force from a road surface. It is determined whether the situation is a reverse input by receiving, and the magnitude of the amount of correction of at least one of the steering damping force and the steering friction force in the reverse input situation is the steering attenuation in the positive input situation A vehicle steering assist device that changes a correction amount of at least one of the steering damping force and the steering friction force so as to be larger than a correction amount of at least one of the force and the steering friction force. 7. The vehicle steering assist device according to claim 5, wherein the control device is configured to generate energy for the steering system based on a product of a steering torque, a differential value of the steering torque, and a rate of change of energy of the steering system. The vehicle steering assist device determines whether the input state of the vehicle is a state of a positive input by a driver's steering or a state of a reverse input due to the steering wheel receiving a force from the road surface.

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