Steering gear

Abstract

The vehicle is steered by appropriately utilizing information from two control devices. [Solution] The steering device 100 includes a first operating device 110 that outputs first operation information indicating a first amount of operation by the driver, a second operating device 120 that outputs second operation information indicating a second amount of operation by the driver, and a control device 130 that outputs steering information for steering the steering wheels 200. The control device 130 includes an information acquisition unit 131 that acquires the first operation information and the second operation information, a steering ratio derivation unit 132 that derives first steering angle information indicating the steering angle of the steering wheels 200 based on the first operation information and second steering angle information indicating the steering angle of the steering wheels 200 based on the second operation information, and a steering information derivation unit 133 that derives steering information based on the first steering angle information and the second steering angle information. The maximum value of the first steering angle information is greater than the maximum value of the second steering angle information.

Description

Technical Field

[0001] The present disclosure relates to a steering device that steers a vehicle by operations respectively performed by a driver on two different devices.

Background Art

[0002] Patent Document 1 describes a technique related to a steering device that can steer a vehicle by operations in two different directions, such as the direction of rotating a steering wheel and the direction of tilting it.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, Patent Document 1 describes a technique for determining a failure based on input values of operations when operating in two operation directions, and does not execute steering of the vehicle in each of the two operation directions.

[0005] Therefore, the present invention provides a steering device that can execute steering of a vehicle with each of two different devices.

Means for Solving the Problems

[0006] One steering device according to the present invention comprises a first operating device that outputs first operation information indicating a first amount of operation by the driver, a second operating device that outputs second operation information indicating a second amount of operation by the driver, and a control device that outputs steering information for steering the steering wheels, wherein the control device comprises an information acquisition unit that acquires the first operation information and the second operation information, a steering ratio derivation unit that derives first steering angle information indicating the steering angle of the steering wheels based on the first operation information and second steering angle information indicating the steering angle of the steering wheels based on the second operation information, and a steering information derivation unit that derives the steering information based on the first steering angle information and the second steering angle information, wherein the maximum value of the first steering angle information is greater than the maximum value of the second steering angle information. [Effects of the Invention]

[0007] According to the present invention, the direction of the vehicle can be changed significantly by operating one of the two operating devices, and the direction of the vehicle can be changed slightly by operating the other operating device, allowing the driver to steer by using the appropriate operating device depending on the driving situation. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 shows the overall configuration of the steering system. [Figure 2] Figure 2 is a block diagram showing the functional configuration of the control device. [Figure 3] Figure 3 shows the overall configuration of the steering system according to alternative example 1. [Figure 4] Figure 4 shows the overall configuration of the steering system according to alternative example 2. [Figure 5] Figure 5 shows the overall configuration of the steering system according to alternative example 3. [Figure 6] Figure 6 shows the overall configuration of the steering system according to alternative example 4. [Modes for carrying out the invention]

[0009] The following describes embodiments of the steering device according to the present invention with reference to the drawings. Note that the following embodiments are examples provided to illustrate the present invention and are not intended to limit it. For example, the shapes, structures, materials, components, relative positional relationships, connection states, numerical values, formulas, the content of each step in the method, and the order of each step shown in the following embodiments are examples and may include content not described below. Furthermore, geometric expressions such as parallel and orthogonal may be used, but these expressions do not indicate mathematical rigor and include substantially acceptable errors and deviations. Similarly, expressions such as simultaneous and identical also include substantially acceptable ranges.

[0010] Furthermore, the drawings are schematic diagrams that have been appropriately emphasized, omitted, or had their proportions adjusted to illustrate the present invention, and therefore differ from the actual shapes, positional relationships, and proportions. Also, the X, Y, and Z axes shown in the drawings represent orthogonal coordinates arbitrarily set for the purpose of explaining the drawings. In other words, the Z axis is not necessarily an axis along the vertical direction, and the X and Y axes are not necessarily located in the horizontal plane.

[0011] Furthermore, in the following, multiple inventions may be comprehensively described as a single embodiment. Also, some of the content described below is described as an optional component relating to the present invention.

[0012] Figure 1 shows the overall configuration of the steering system 100. The steering system 100 comprises a first operating device 110, a second operating device 120, and a control device 130, and is a system that can steer the steering wheels 200 mounted on a vehicle such as a passenger car based on signals output by operating at least one of the first operating device 110 and the second operating device 120. The steering system 100 can be exemplified by a system in which the first operating device 110 and the second operating device 120 and the steering wheels 200 are mechanically separated at all times, or by a structure in which the mechanical connection between the first operating device 110 and the second operating device 120 and the steering wheels 200 can be separated by a clutch or the like. In this embodiment, a so-called linkless steer-by-wire system is used, in which the first operating device 110 and the second operating device 120 and the steering wheels 200 are not connected by mechanical elements such as links, and the steering wheels 200 are steered based only on signals (information). In this embodiment, the steering device 100 is a device that can steer a pair of steering wheels 200 simultaneously, and comprises a steering motor 140 and an operating member 142.

[0013] The operating member 142 is a member that operates in response to the output of the steering motor 140, generating thrust in the direction of its extension, and steering a pair of steering wheels 200 via a link mechanism or the like. The type of operating member 142 is not limited, but in this embodiment, the operating member 142 is a rack bar, and rack teeth are provided at one of the positions in the longitudinal direction. The operating member 142 generates thrust in the direction of its extension when the rotation of the pinion gear connected to the steering motor 140 is transmitted to the rack teeth, and simultaneously steers the two steering wheels 200 via tie rods 201 or the like connected to both ends of the operating member 142. The steering motor 140 is equipped with a motor driver 141 (see Figure 2) and operates based on steering information acquired from the control device 130.

[0014] The first operating device 110 is a device that outputs first operation information indicating a first operation amount generated by the operator's operation. The first operating device 110 converts the operation amount, which is the amount of operation performed by the operator, into an electrical signal and outputs it as first operation information, by the operator causing at least one of the following to occur on a part of the mechanical structure: rotation, tilting, and sliding. The first operating device 110 may also output the operator's operation amount as first operation information by moving a finger, hand, etc., on the surface of an electrical device such as a touchpad.

[0015] In this embodiment, the first operating device 110 includes a rod-shaped tilting member 111 that tilts 101 (see Figure 1) by operation with one hand of the driver, and a first detection device 112 that detects the tilting angle of the tilting member 111 as an operation amount and outputs it as first operation information. The first operating device 110 has a predetermined neutral position, which is the position in which the vehicle moves straight, and is provided with a mechanism that returns the tilting member 111 to the neutral position when no force is applied to the tilting member 111. The first operating device 110 outputs first operation information that includes the angle from the neutral position when the tilting member 111 is tilted in the first tilting direction, the angle from the neutral position when it is tilted in the second tilting direction opposite to the first tilting direction, and information that can distinguish the direction. The first operation information may indicate the operation amount from the neutral position, or it may be normalized using the maximum operation amount from the neutral position.

[0016] The angle sensor provided by the first operating device 110 is not limited. In this embodiment, the angle sensor acquires the absolute tilt angle of the tilting member 111. The absolute tilt angle is information that allows us to acquire an angle that includes the direction of rotation, such as whether it is rotating clockwise or counterclockwise, from the neutral position of the tilting member 111. The type of angle sensor is not limited, but for example, an angle sensor can be exemplified that meshes a first gear that rotates synchronously with the tilting member 111 with a second gear and a third gear with different numbers of teeth, and acquires the absolute tilt angle based on the phase difference between the second gear and the third gear.

[0017] The second operating device 120 is a device that outputs second operation information indicating a second operation amount based on an operation that can be executed independently of the operation of the first operating device 110 by the driver. Note that the second operating device 120 is capable of executing the operation of the second operating device simultaneously with the first operating device 110, such as the tilting 101 and rotation 102 shown in FIG. 1. The fact that the operations can be executed simultaneously means that, as shown in FIG. 1, the driver may be able to operate the first operating device 110 and the second operating device 120 with one hand, or the driver may be able to operate the first operating device 110 and the second operating device 120 with each of both hands (see FIG. 3). The type of the second operating device 120 may be the same as or different from that of the first operating device 110.

[0018] In the case of the present embodiment, the second operating device 120 includes a rotating member 121 that rotates by the operation of the fingers of one hand of the driver, for example, the thumb and index finger, and rotates 102 (see FIG. 1), and a second detection device 122 that detects the rotation angle of the rotating member 121 as an operation amount and outputs second operation information. The rotating member 121 is attached to the tilting member 111 so as to rotate about the tilting member 111 as an axis. The second operating device 120 has a neutral position that is a position for straight-aheading the vehicle, and in a state where no force is applied to the rotating member 121, a mechanism is provided such that the rotating member 121 returns to the neutral position. The second operating device 120 outputs second operation information including the rotation angle from the neutral position when the rotating member 121 is rotated in the first rotation direction, the rotation angle from the neutral position when rotated in the second rotation direction opposite to the first rotation direction, and information that can distinguish the direction. Note that the second operation information may indicate the operation amount from the neutral position, or may be normalized using the maximum operation amount from the neutral position.

[0019] The angle sensor included in the second operating device 120 is not limited, and may be the same type as or different from the angle sensor included in the first operating device 110. In the case of the present embodiment, a sensor of the same type as the angle sensor included in the first operating device is adopted as the angle sensor.

[0020] FIG. 2 is a block diagram showing the functional configuration of the control device 130. The control device 130 is a so-called ECU (Electronic Control Unit) that outputs steering information for controlling the steering of the steering wheel 200 based on the first operation information obtained from the first operation device 110 and the second operation information obtained from the second operation device 120. The control device 130 includes a processor and, as a processing unit realized by the processor executing a steering program, includes an information acquisition unit 131, a steering rate derivation unit 132, and a steering information derivation unit 133.

[0021] The information acquisition unit 131 acquires the first operation information from the first detection device 112 and the second operation information from the second detection device 122. In the case of this embodiment, the information acquisition unit 131 acquires the first operation information and the second operation information by communication such as SENT (Single Edge Nibble Transmission) communication and CAN (Controller Area Network). SENT communication is a communication protocol for accurately and cost-effectively transmitting sensor data to the ECU. CAN is a standard for executing communication between control devices using the in-vehicle network standard protocol.

[0022] When the information acquisition unit 131 acquires the first operation information indicating the operation amount from the neutral position, it may update the first operation information with the operation amount normalized using the maximum operation amount from the neutral position. Further, when the information acquisition unit 131 acquires the second operation information indicating the operation amount from the neutral position, it may update the second operation information with the operation amount normalized using the maximum operation amount from the neutral position.

[0023] The steering ratio derivation unit 132 derives first steering angle information, which indicates the steering angle of the steering wheel 200 based on the first operation information, and second steering angle information, which indicates the steering angle of the steering wheel 200 based on the second operation information, based on the first operation information and second operation information acquired by the information acquisition unit 131. However, if first operation information is not output from the first operating device 110 (for example, if the tilting member 111 is in the neutral position), the information acquisition unit 131 cannot acquire first operation information, and the steering ratio derivation unit 132 may not derive first steering angle information. Also, if second operation information is not output from the second operating device 120 (for example, if the rotating member 121 is in the neutral position), the information acquisition unit 131 cannot acquire second operation information, and the steering ratio derivation unit 132 may not derive second steering angle information.

[0024] The steering angle derivation unit 132 does not have a limited method for deriving the first steering angle information and the second steering angle information, but it derives the first steering angle information and the second steering angle information under the condition that the maximum value of the first steering angle information is greater than the maximum value of the second steering angle information.

[0025] The steering ratio derivation unit 132 may calculate steering angle information using a function that takes operation information as a variable based on predetermined conditions. The function is not limited. For example, the maximum steering angle of the steering wheel 200, the first gain which is the ratio of the first steering angle information based on the first operation information, and the second gain which is the ratio of the second steering angle information to the second operation information may be determined in advance, and the steering ratio derivation unit 132 holds these values ​​as fixed values. Furthermore, if the first operation information and the second operation information acquired by the steering ratio derivation unit 132 are not normalized, the first operation information and the second operation information are normalized. Under these conditions, the steering ratio derivation unit 132 may calculate the first steering angle information and the second steering angle information based on the following equations 1 and 2. First steering angle information = Maximum steering angle * First gain * First operation information ... Equation 1 Second steering angle information = Maximum steering angle * Second gain * Second operation information ... Equation 2 (* indicates multiplication, / indicates division.)

[0026] Furthermore, by setting the first gain > second gain, the condition that the maximum value of the first steering angle information is greater than the maximum value of the second steering angle information is satisfied.

[0027] For example, if the maximum steering angle is 40 degrees (angle from the neutral position of the steering wheel 200), the first gain is 0.7, and the second gain is 0.3, then if the normalized first operation information is 1 and the normalized second operation information is 0.5, the first steering angle information will be 40 * 0.7 * 1 = 28 degrees, and the second steering angle information will be 40 * 0.3 * 0.5 = 6 degrees.

[0028] Furthermore, the steering ratio derivation unit 132 may calculate the first steering angle information and the second steering angle information based on the normalized first operation information and the normalized second operation information, according to the following equations 3 and 4. First steering angle information = First gain * First operation information... Equation 3 Second steering angle information = Second gain * Second operation information... Equation 4

[0029] For example, if the first gain is 2 and the second gain is 0.5, and the normalized first operation information is 0.4 and the normalized second operation information is 0.6, then the first steering angle information will be 2 * 0.4 = 0.8 and the second steering angle information will be 0.5 * 0.6 = 0.3.

[0030] Furthermore, the steering ratio derivation unit 132 may use the normalized first operation information and the normalized second operation information to calculate the first steering angle information and the second steering angle information based on the following equations 5 and 6, using an arbitrarily set constant b1 and an arbitrarily set constant b2. First steering angle information = First gain * First operation information + b1 ... Equation 5 Second steering angle information = second gain * second operation information + b2...Equation 6

[0031] For example, if the first gain is 1, the second gain is 0.5, b1 is 1, and b2 is 0, then if the normalized first operation information is 0.4 and the normalized second operation information is 0.6, then the first steering angle information will be 1*0.4+1=1.4 and the second steering angle information will be 0.5*0.6=0.3.

[0032] The steering information derivation unit 133 derives steering information, which is information for steering the steering wheel 200, based on the first steering angle information and the second steering angle information derived by the steering ratio derivation unit 132. The method by which the steering information derivation unit 133 derives the steering information is not limited. In this embodiment, the steering information derivation unit 133 derives the steering information based on a function that uses the first steering angle information and the second steering angle information as variables. The contents of the steering information are all parameters related to the steering of the steering wheel 200, and examples include at least one of the steering angle command value, steering torque command value, and steering motor current command value.

[0033] For example, if the steering information derivation unit 133 calculates the first steering angle information and the second steering angle information using equations 1 and 2, the steering information derivation unit 133 may derive the steering information based on the following equation 7. Steering angle information = First steering angle information + Second steering angle information ... Equation 7

[0034] For example, using the numerical values ​​exemplified in the explanation of Equations 1 and 2 used by the steering ratio derivation unit 132, the steering information becomes 28 + 6 = 34 degrees.

[0035] Furthermore, if the steering information derivation unit 132 calculates the first steering angle information and the second steering angle information using equations 3, 4, or 5 and 6, the steering information derivation unit 133 may derive the steering information based on the following equation 8. Steering angle information = Maximum steering angle * First steering angle information * Second steering angle information ... Equation 8

[0036] For example, using the numerical values ​​exemplified in the explanation of equations 3 and 4 used by the steering ratio derivation unit 132, the steering information becomes 40 * 0.8 * 0.3 = 9.6 degrees.

[0037] Furthermore, using the numerical values ​​exemplified in the explanation of Equations 5 and 6 used by the steering ratio derivation unit 132, the steering information becomes 40 * 1.4 * 0.3 = 16.8 degrees. By using the first steering angle information and second steering angle information calculated by Equations 5 and 6, which are linear functions in which b1 and b2 are added, the value of Equation 5 will not become 0 even when the first control device 110 is in the neutral position, thus avoiding a situation where the steering information is maintained at 0 degrees.

[0038] Furthermore, the steering information derivation unit 133 may derive steering information based on the maximum steering angle, using either the first steering angle information or the second steering angle information derived from only the larger of the normalized first operation information and the normalized second operation information.

[0039] Furthermore, the steering information derivation unit 133 may derive steering information based on the larger of the normalized first steering angle information and the normalized second steering angle information.

[0040] The steering information derived by the steering information derivation unit 133 and output to the steering motor 140 is the ratio of the steering angle to the maximum steering angle of the steering wheel 200, and the maximum value may be 1. In other words, a normalized value based on the maximum steering angle of the steering wheel 200 may be output to the motor driver 141.

[0041] It should be noted that the present invention is not limited to the embodiments described above. For example, other embodiments of the present invention may be realized by arbitrarily combining the components described herein, or by excluding some of the components. Furthermore, modifications obtained by applying various modifications to the above embodiments that a person skilled in the art could conceive of without departing from the spirit of the present invention, that is, the meaning indicated by the wording in the claims, are also included in the present invention.

[0042] For example, the first operating device 110 and the second operating device 120 may be arranged separately and independently, as shown in Figure 3. In this case, the first operating device 110 and the second operating device 120 may be operated simultaneously with different hands.

[0043] Furthermore, as shown in Figure 4, the first operating device 110 may be a mechanism in which the operator inputs the amount of operation by sliding the member 103, and the second operating device 120 may be a mechanism in which the operator inputs the amount of operation by tilting the same member.

[0044] Furthermore, as shown in Figure 5, the driver may input an operation amount to the first operating device 110 by tilting or the like, and the second operating device 120 may be a switch that can output a choice between 0 and 1 as the operation amount. In this case, if the steering ratio derivation unit 132 obtains one of the two operation amounts from the second operating device 120, it may derive the first steering angle information based on the first operation information obtained from the first operating device 110, and if the other of the two operation amounts is obtained from the second operating device 120, it may use the first operation information obtained from the first operating device 110 as the second operation information and derive the second steering angle information based on the second operation information.

[0045] Furthermore, while the methods for calculating steering angle information and steering information using functions in the steering ratio derivation unit 132 and steering information derivation unit 133 have been explained, it is also acceptable to derive at least one of the steering angle information and steering information using maps or databases.

[0046] Furthermore, the choice between using the first operation information or the second operation information may be switched depending on the vehicle's speed.

[0047] Furthermore, as shown in Figure 6, the steering system 100 is equipped with a first steering motor 143 and a second steering motor 144 as steering motors 140, and can also be applied to a left and right independent steer-by-wire system in which each of the pair of steering wheels 200 is independently steered using the first steering motor 143 and the second steering motor 144.

[0048] (summary) The steering system 100 in the first embodiment includes a first operating device 110 that outputs first operation information indicating a first amount of operation by the driver, a second operating device 120 that outputs second operation information indicating a second amount of operation by the driver, and a control device 130 that outputs steering information for steering the steering wheels 200. The control device 130 includes an information acquisition unit 131 that acquires the first operation information and the second operation information, a steering ratio derivation unit 132 that derives first steering angle information indicating the steering angle of the steering wheels 200 based on the first operation information and second steering angle information indicating the steering angle of the steering wheels 200 based on the second operation information, and a steering information derivation unit 133 that derives steering information based on the first steering angle information and the second steering angle information, wherein the maximum value of the first steering angle information is greater than the maximum value of the second steering angle information.

[0049] According to the first embodiment, the driver's operation of the first control device 110 is used for rough steering, for example, steering at low speeds when parking the vehicle, and the driver's operation of the second control device 120 is used for fine steering adjustments, for example, steering at high speeds. Thus, two steering methods can be utilized and used interchangeably depending on the purpose.

[0050] The steering device 100 of the second embodiment includes the first embodiment, and the steering information derivation unit 133 derives steering information based on a function that takes the first steering angle information and the second steering angle information as variables.

[0051] According to the second embodiment, the steering response to operation on at least one of the first operating device 110 and the second operating device 120 can be made faster. In addition, the load on the control device 130 can be reduced.

[0052] The steering device 100 of the third embodiment includes the first embodiment or the second embodiment, and the steering information is the ratio of the steering angle to the maximum steering angle of the steering wheel 200, with a maximum value of 1.

[0053] According to the third embodiment, if steering information exceeding 1 is output to the steering motor 140, there is a risk that the steering wheel 200 will be turned beyond the maximum steering amount. Therefore, software-based regulation can be implemented by setting the maximum value of the steering information to 1 in advance.

[0054] The steering device 100 of the fourth embodiment includes any of the first to third embodiments, and the steering information derivation unit 133 derives steering information based on the larger of the normalized first operation information and the normalized second operation information.

[0055] According to the fourth embodiment, when the first operating device 110 and the second operating device 120 are operated simultaneously, an action can be performed that reflects the driver's intention to either steer the vehicle a large or small turn.

[0056] The steering device 100 of the fifth embodiment includes any of the first to third embodiments, and the steering information derivation unit 133 derives steering information based on the larger of the normalized first steering angle information and the normalized second steering angle information.

[0057] According to the fifth embodiment, when the first operating device 110 and the second operating device 120 are operated simultaneously, an action can be performed that reflects the driver's intention to either steer the vehicle significantly or significantly. [Industrial applicability]

[0058] The present invention can be used in steering systems that include multiple operating devices for steering a vehicle. [Explanation of Symbols]

[0059] 100...Steering device, 101...Tilt, 102...Rotation, 103...Slide, 110...First operating device, 111...Tilting member, 112...First detection device, 120...Second operating device, 121...Rotating member, 122...Second detection device, 130...Control device, 131...Information acquisition unit, 132...Steering ratio derivation unit, 133...Steering information derivation unit, 140...Steering motor, 141...Motor driver, 142...Operating member, 143...First steering motor, 144...Second steering motor, 200...Steering wheel, 201...Tie rod, 210...Operating member

Claims

1. A first operating device that outputs first operating information indicating the first operating amount by the driver, A second operating device that outputs second operating information indicating a second operating amount by the driver, It comprises a control device that outputs steering information for steering the steering wheels, The control device is An information acquisition unit that acquires the first operation information and the second operation information, A steering ratio derivation unit that derives first steering angle information indicating the steering angle of the steering wheel based on the first operation information, and second steering angle information indicating the steering angle of the steering wheel based on the second operation information, The system includes a steering information derivation unit that derives steering information based on the first steering angle information and the second steering angle information, The maximum value of the first steering angle information is greater than the maximum value of the second steering angle information. Steering gear.

2. The steering information output unit is, The steering information is derived based on a function that takes the first steering angle information and the second steering angle information as variables. The steering device according to claim 1.

3. The steering information is the ratio of the steering angle to the maximum steering angle of the steering wheel, with a maximum value of 1. The steering device according to claim 1 or 2.

4. The steering information output unit is, The steering information is derived based on the larger of the normalized first operation information and the normalized second operation information. The steering device according to claim 1 or 2.

5. The steering information output unit is, The steering information is derived based on the larger of the first steering angle information and the second steering angle information. The steering device according to claim 1 or 2.

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