JP2020006806A - Contact state detection device, contact state detection method and program - Google Patents

Abstract

To provide a contact state detection device and the like which improve detection accuracy of a contact state to a steering member.SOLUTION: A contact state detection device 100 for detecting a contact state of a steering device 1 for vehicle to a steering wheel 11 includes: a torque sensor 21 for detecting torque generating in a steering shaft 5; and a state determination part 515 for outputting information showing a hands-on state or a hands-off state with respect to the steering wheel 11 by calculating using input data comprising a plurality of detection values of the torque sensor 21.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a device for detecting a contact state with a steering member, a method for detecting a contact state, and a program.

  2. Description of the Related Art In recent years, technologies for detecting a contact state of a driver with a steering member such as a steering wheel have been studied in order to control a vehicle. For example, Patent Literature 1 discloses a technique for determining a steering wheel free state in which a driver has released his / her hand from a steering wheel. According to this technology, a disturbance torque as an externally input torque is estimated based on a steering angle and a steering angular velocity of a steering, and the disturbance torque and a shaft torque of a rotating shaft of the steering are added to calculate a steering torque. The torque is estimated. Then, when the state in which the absolute value of the steering torque is less than the threshold value has passed for a predetermined time, it is determined that the steering wheel is in the free state.

JP-A-2002-104223 JP, 2017-114324, A

  In the technique of Patent Document 1, there is a possibility that the time required for detecting the handle free state becomes long. Furthermore, when the driver is gripping the steering wheel with a small steering torque, it may be determined that the steering wheel is in the free state. For this reason, the technique of Patent Literature 1 may cause erroneous detection.

  Therefore, the present invention provides a contact state detection device, a contact state detection method, and a program that improve the detection accuracy of the contact state with the steering member.

  A contact state detection device according to one aspect of the present invention is a contact state detection device that detects a contact state of a vehicle steering device with a steering member, and a torque detection unit that detects a torque generated in the steering member. A calculation unit that calculates information using input data composed of a plurality of detection values of the torque detection unit to output information indicating a hands-on state or a hands-off state for the steering member.

  A contact state detection method according to one aspect of the present invention is a contact state detection method for detecting a contact state of a steering member of a vehicle with a steering member, and acquires a plurality of detection values of torque generated in the steering member. By using input data composed of a plurality of detected values of the torque, information indicating a hands-on state or a hands-off state with respect to the steering member is output.

  A program according to one aspect of the present invention obtains a plurality of detected values of a torque generated in a steering member of a vehicle steering device, and performs a calculation using input data including the plurality of detected values of the torque. And causing the computer to output information indicating a hands-on state or a hands-off state for the steering member.

  ADVANTAGE OF THE INVENTION According to the contact state detection apparatus etc. which concern on this invention, it becomes possible to improve the detection accuracy of the contact state with a steering member.

FIG. 1 is a schematic diagram illustrating an example of a configuration of a vehicle steering device including a contact state detection device according to a first embodiment. FIG. 2 is a block diagram showing an example of a functional configuration of the contact state detection device according to the first embodiment. The figure which shows an example of the flow of a process of each component of the contact state detection apparatus which concerns on Embodiment 1. Diagram showing an example of a neural network model Diagram for explaining learning of the learning device Flowchart showing an example of a contact state detection operation of the contact state detection device according to the first embodiment. FIG. 4 is a block diagram showing an example of a functional configuration of a contact state detection device according to Embodiment 2. The figure which shows an example of the flow of a process of each component of the contact state detection apparatus which concerns on Embodiment 2. Block diagram showing an example of a functional configuration of a contact state detection device according to Embodiment 3. The figure which shows an example of the flow of a process of each component of the contact state detection apparatus which concerns on Embodiment 3.

  Hereinafter, a contact state detection device and the like according to an embodiment will be described with reference to the drawings. The embodiment described below shows a comprehensive or specific example. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of constituent elements, steps (processes), order of steps, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. Absent. Further, among the components in the following embodiments, components not described in the independent claims indicating the highest concept are described as arbitrary components. In addition, each drawing is a schematic diagram and is not necessarily strictly illustrated. Further, in each of the drawings, substantially the same components are denoted by the same reference numerals, and redundant description may be omitted or simplified in some cases.

[Embodiment 1]
A configuration of a contact state detecting device 100 according to Embodiment 1 of the present invention and a vehicle steering device 1 including the contact state detecting device 100 will be described. In the present embodiment, a description will be given assuming that contact state detection device 100 is provided in vehicle steering device 1 mounted on a vehicle. Examples of vehicles are automobiles, trucks, buses, two-wheeled vehicles, transport vehicles, railways, construction machines, agricultural machines, and cargo handling machines. In the present embodiment, the vehicle is an automobile, and the automobile may be any of an automobile equipped with an engine, a hybrid automobile equipped with an engine and a motor, and an electric automobile equipped with a motor without an engine.

  FIG. 1 is a schematic diagram illustrating an example of a configuration of a vehicle steering device 1 including a contact state detection device 100 according to the first embodiment. As shown in FIG. 1, the vehicle steering device 1 is a steering device mounted on a vehicle A and performing torque assist for steering by a rotational driving force of a motor. The vehicle steering device 1 includes a steering mechanism 2 operated by a driver of the vehicle A, a steering mechanism 3 that steers steered wheels 60 in accordance with an input to the steering mechanism 2 by the driver, and steering of the driver. And an auxiliary mechanism 4 for assisting the user. The steered wheels 60 are steering wheels of the vehicle A.

  The steering mechanism 2 includes a steering shaft 5 connected to a steering wheel 11. In the case of the present embodiment, the steering shaft 5 includes a column shaft 5a, an intermediate shaft 5b, and a pinion shaft 5c. The column shaft 5a, the intermediate shaft 5b, and the pinion shaft 5c are connected in this order via a universal joint at their respective ends so that the column shaft 5a can rotate in a bent state. The column shaft 5a is connected to the steering wheel 11. The pinion shaft 5c is connected to a rack shaft 6 of the steering mechanism 3 described later. Here, the steering wheel 11 and the steering shaft 5 are examples of a steering member.

  The steering mechanism 3 includes a rack shaft 6 connected to the steered wheels 60 and a rack and pinion device 7. The rack and pinion device 7 converts the rotation of the pinion shaft 5c into a reciprocating motion of the rack shaft 6. The turning mechanism 3 converts the rotational driving force transmitted from the pinion shaft 5c into the linear driving force of the rack shaft 6 and transmits the linear driving force to the steered wheels 60, thereby rotating the steered wheels 60 in the steered direction.

  The auxiliary mechanism 4 includes a motor 8 that applies a steering assist force to the steering shaft 5 and a speed reducer 9 that transmits a rotational driving force of the motor 8 to the steering shaft 5. The motor 8 operates under the control of an electronic control unit (ECU) 50 described later. The speed reducer 9 is a device that is connected to the motor 8 and applies an assist force to the steering shaft 5 to assist the steering by using the motor 8 as a drive source. The speed reducer 9 reduces the rotational speed of the motor 8 and increases the rotational driving force to transmit the rotational driving force to the steering shaft 5. An example of the motor 8 is an electric motor. An example of the speed reducer 9 is a worm speed reducer. The worm speed reducer includes a worm shaft 9a that is driven to rotate by a motor 8, and a worm wheel 9b that rotates integrally with the steering shaft 5. The worm shaft 9a is a screw gear having spiral teeth on the outer peripheral surface, and the worm wheel 9b is a disk gear having a plurality of teeth on the outer periphery. The teeth of the small-diameter worm shaft 9a mesh with the teeth of the large-diameter worm wheel 9b.

  In the case of the present embodiment, the speed reducer 9 is connected to the pinion shaft 5c. However, the speed reducer 9 may be connected to the column shaft 5a or the intermediate shaft 5b, or may be connected to the rack shaft 6.

  The column shaft 5a includes an input shaft 5aa, an output shaft 5ab, and a torsion bar 5ac. The input shaft 5aa is connected to the steering wheel 11, and the steering force of the driver is input from the steering wheel 11. The output shaft 5ab is connected to the intermediate shaft 5b, and transmits the driver's steering force input from the steering wheel 11 to the intermediate shaft 5b. The torsion bar 5ac is disposed between the input shaft 5aa and the output shaft 5ab, and transmits the steering force input to the input shaft 5aa to the output shaft 5ab. The torsion bar portion 5ac is configured to have lower rigidity in the torsion direction about the axis than the input shaft portion 5aa and the output shaft portion 5ab. An example of a constituent material of the torsion bar portion 5ac is spring steel. When the steering force is input to the input shaft portion 5aa, the torsion bar portion 5ac transmits the steering force to the output shaft portion 5ab while twisting about the axis.

  Further, the vehicle steering system 1 includes a torque sensor 21 for detecting a torque applied to the steering shaft 5 by the driver via the steering wheel 11. The torque sensor 21 is disposed on the torsion bar 5ac, and detects torque by detecting the amount of torsion of the torsion bar 5ac, that is, the relative rotation angle of the input shaft 5aa and the output shaft 5ab. The torque detected by the torque sensor 21 corresponds to a steering torque applied to the steering wheel 11 by the driver for steering. The torque sensor 21 transmits a detection signal to the ECU 50. Here, the torque sensor 21 is an example of a torque detector.

  Further, the vehicle steering system 1 includes a rotation angle sensor 22 that detects the rotation angle of the input shaft 5aa. The rotation angle sensor 22 is disposed on the input shaft 5aa, and detects a rotation amount around the axis of the input shaft 5aa, that is, a rotation angle. The rotation angle detected by the rotation angle sensor 22 corresponds to a steering angle applied to the steering wheel 11 by the driver for steering. The rotation angle sensor 22 transmits a detection signal to the ECU 50. Here, the rotation angle sensor 22 is an example of a rotation amount detection unit.

  Further, the vehicle steering system 1 includes an ECU 50. The ECU 50 is electrically connected to the motor 8, the torque sensor 21, the rotation angle sensor 22, and the like. Further, the ECU 50 is electrically connected to a vehicle speed sensor 31 mounted on the vehicle A, and acquires a signal indicating the vehicle speed, which is the speed of the vehicle A, from the vehicle speed sensor 31. The ECU 50 controls the current supplied to the motor 8 based on the torque and vehicle speed signals acquired from the torque sensor 21 and the vehicle speed sensor 31, and controls the assist force that the motor 8 applies to the pinion shaft 5c. The ECU 50 detects a contact state of the driver with the steering wheel 11 based on the torque and rotation angle signals obtained from the torque sensor 21 and the rotation angle sensor 22. Specifically, the ECU 50 detects whether the driver is in the hands-on state in which the steering wheel 11 is gripped or the driver is in the hands-off state in which the driver is not gripping the steering wheel 11. The details of the ECU 50 will be described later. The ECU 50, the torque sensor 21, and the rotation angle sensor 22 constitute a contact state detection device 100 according to the present embodiment.

  The ECU 50 may be configured by a microcomputer including a processor such as a CPU (Central Processing Unit) or a DSP (Digital Signal Processor) and a memory. Examples of the memory may be a volatile memory such as a random access memory (RAM) and a non-volatile memory such as a read-only memory (ROM). Some or all of the functions of the ECU 50 may be achieved by the CPU executing a program recorded in the ROM using the RAM as a working memory. Part or all of the functions of the ECU 50 may be achieved by a dedicated hardware circuit such as an electronic circuit or an integrated circuit. Some or all of the functions of the ECU 50 may be configured by a combination of the above-described software functions and hardware circuits. Communication between the ECU 50, the motor 8, and each of the above-described sensors and the like may be communication via a vehicle-mounted network such as a CAN (Controller Area Network).

  The configuration of the contact state detection device 100 including the ECU 50 will be described with reference to FIGS. FIG. 2 is a block diagram illustrating an example of a functional configuration of the contact state detection device 100 according to the first embodiment. FIG. 3 is a diagram illustrating an example of a processing flow of each component of the contact state detection device 100 according to the first embodiment. The contact state detection device 100 includes a torque sensor 21, a rotation angle sensor 22, and an ECU 50. The ECU 50 includes a control unit 51, a drive circuit 52, and a current detection unit 53. The control unit 51 includes a first filter 511, a second filter 512, a first storage unit 513, a second storage unit 514, a state determination unit 515, a storage unit 516, and a motor control unit 517.

  The drive circuit 52 is controlled by the control unit 51 and supplies electric power of a battery of the vehicle A (not shown) to the motor 8. The drive circuit 52 is configured by an inverter circuit. The current detection unit 53 detects the magnitude of the motor current, which is the current flowing through the motor 8, and outputs the detected current to the control unit 51. The current detection unit 53 is configured by a circuit for measuring a current and the like. The first storage unit 513, the second storage unit 514, and the storage unit 516 enable storage and retrieval of various information. The first storage unit 513, the second storage unit 514, and the storage unit 516 are realized by a storage device such as a semiconductor memory such as a ROM, a RAM, or a flash memory, a hard disk drive, or an SSD (Solid State Drive).

  The storage unit 516 stores various information such as a threshold value, a map, a mathematical expression, and a determination model to be described later used for the operation of the control unit 51. The storage unit 516 may store a program for operating the control unit 51.

  The first storage unit 513 stores data of the detection value of the torque sensor 21 acquired via the first filter 511. The first storage unit 513 stores data of a plurality of detection values, and specifically stores time-series data of torque values detected by the torque sensor 21. The second storage unit 514 stores data of the detection value of the rotation angle sensor 22 obtained via the second filter 512. The second storage unit 514 stores data of a plurality of detection values, and specifically stores time-series data of angle values detected by the rotation angle sensor 22. The time-series data is data that is sequentially observed or acquired along with the flow of time. The detection values of the torque sensor 21 and the rotation angle sensor 22 include measurement values associated with measurement times. The association between the measurement time and the measurement value may be performed by, for example, the torque sensor 21 and the rotation angle sensor 22 when the measurement value is obtained. The first storage unit 513 and the second storage unit 514 function as buffers for temporarily storing data. In the present embodiment, the first storage unit 513 and the second storage unit 514 store data acquired for one second or more, which is a predetermined period or more, but the present invention is not limited to this. In the present embodiment, the torque sensor 21 and the rotation angle sensor 22 perform detection at a sensing cycle of 1 msec, but the present invention is not limited to this.

  In the present embodiment, the first storage unit 513, the second storage unit 514, and the storage unit 516 are included in the control unit 51 in the ECU 50, but may be provided separately from the control unit 51. May be arranged outside.

  The motor control unit 517 drives and controls the drive circuit 52 based on the vehicle speed detected by the vehicle speed sensor 31, the torque detected by the torque sensor 21, and the motor current detected by the current detection unit 53. The steering assist according to the steering situation is realized. Specifically, the motor control unit 517 determines a current command value that is a target value of the motor current flowing through the motor 8 based on the torque and the vehicle speed. The current command value corresponds to a target value of the steering assist force (also referred to as “assist torque”) according to the steering situation. Then, the motor control unit 517 controls the drive of the drive circuit 52 so that the motor current detected by the current detection unit 53 approaches the current command value. Further, the motor control unit 517 controls the drive of the drive circuit 52 based on the determination result of the state determination unit 515 described later. Specifically, when the determination result is the hands-on state, the motor control unit 517 causes the drive circuit 52 to supply power to the motor 8 and to perform steering assist. When the determination result is the hands-off state, the motor control unit 517 stops the driving support function (ADAS) such as the lane keeping function (LKA), but continues the steering assist.

  The first filter 511 is a low-pass filter, acquires a signal indicating the detected value of the torque output from the torque sensor 21, and removes a high-frequency component from the signal. The first filter 511 stores the signal after removing the high-frequency component in the first storage unit 513. The second filter 512 is a low-pass filter, acquires a signal indicating the detected value of the angle output from the rotation angle sensor 22, and removes a high-frequency component from the signal. The second filter 512 stores the signal after removing the high-frequency component in the second storage unit 514. As a result, signals such as noise unrelated to steering are removed. Then, the first storage unit 513 stores time-series data of torque values, and the second storage unit 514 stores time-series data of angle values. An example of the first filter 511 and the second filter 512 is a digital filter. Here, the first filter 511 and the second filter 512 are examples of a filter unit.

  The state determination unit 515 uses the torque value detected by the torque sensor 21 and the angle value detected by the rotation angle sensor 22 as input data. The state determination unit 515 performs a calculation using the input data to determine whether the driver is in the hands-on state in which the steering wheel 11 is gripped or in the hands-off state in which the driver is not gripping the steering wheel 11 (hand-off state). ) Is determined. State determination section 515 outputs the determination result to motor control section 517. Here, the state determination unit 515 is an example of a calculation unit, and the determination result is an example of information indicating a hands-on state or a hands-off state for the steering member.

  State determination section 515 outputs a determination result using the determination model. The judgment model is stored in the storage unit 516. The decision model outputs output data for the input data. The determination model uses the time-series data of the torque value stored in the first storage unit 513 and the time-series data of the angle value stored in the second storage unit 514 as input data, and determines the determination result of the hands-on state or the hands-off state. Is output data. For example, the state determination unit 515 determines, via the first storage unit 513, one of a predetermined period of time from the measurement point of the latest torque value T (k) of the torque values detected by the torque sensor 21 after the application of the first filter 511. The data of the torque values T (k) to T (kn) measured before going back for seconds is acquired. Furthermore, the state determination unit 515 determines, via the second storage unit 514, a predetermined period of time from the measurement time of the latest angle value θ (k) of the detection angle values of the rotation angle sensor 22 after the application of the second filter 512. The data of the angle values θ (k) to θ (kn) measured before going back for one second is acquired. The data of the torque values T (k) to T (kn) and the angle values θ (k) to θ (kn) are obtained from the latest measurement of the torque value T (k) and the angle value θ (k). This is data acquired in the past second. The determination model receives torque values T (k) to T (kn) and angle values θ (k) to θ (kn) as input data and outputs output data.

  In the present embodiment, the judgment model improves judgment accuracy by learning using learning data. The learning model applied to the judgment model is a neural network (Neural Network) or a convolutional neural network (Convolutional Neural Network), and the learning method is a method by learning using Neuroevolution (such as Genetic Programming) or Deep Learning. You may. A neural network is an information processing model that models the nervous system. The neural network is composed of a plurality of node layers including an input layer and an output layer. The node layer includes one or more nodes. For example, as shown in FIG. 4, when the neural network is composed of an input layer, a hidden layer, and an output layer, the neural network outputs information from the input layer to the hidden layer with respect to information input to a node of the input layer. Processing, processing in the intermediate layer, output processing from the intermediate layer to the output layer, and processing in the output layer are sequentially performed, and an output result matching the input information is output. Each node in one layer is connected to each node in the next layer, and the connection between nodes is weighted. The information of the node of one layer is weighted with the connection between the nodes, and is output to the node of the next layer. FIG. 4 is a diagram illustrating an example of a neural network model.

  The machine learning of the determination model may be performed by the ECU 50, or may be performed by the learning device 70 that is an external device such as a server device arranged at a position apart from the ECU 50. In the present embodiment, the learning device 70 performs machine learning of the determination model. The determination model learned by the learning device 70 may be sent to the storage unit 516 by a recording medium such as a nonvolatile memory, or by wireless communication via a communication network such as the Internet.

  The learning of the judgment model is performed offline by the learning device 70. Note that online indicates that the vehicle is running, and offline indicates that the vehicle is not running. Offline, data acquired in advance when the vehicle is not running, such as data acquired in advance and data artificially created, is used. The learning with the teacher signal (also referred to as “supervised learning”) is used for learning the judgment model. In supervised learning, the weighting in the neural network is adjusted so that the input data, that is, the output data of the judgment model for the input signal matches the teacher signal.

  In the present embodiment, as shown in FIG. 5, the learning unit 71 included in the learning device 70 forms a determination neural network (also referred to as “determination NN”) that configures a determination model from the driving histories of a plurality of drivers. To construct. FIG. 5 is a diagram for explaining learning by the learning device 70. The plurality of drivers may be an unspecified number of drivers, and may or may not be related to the vehicle A. The driving history of each driver is data acquired during driving of each driver, and includes steering torque, a steering angle when the steering torque is generated, and hands-on or a steering angle when the steering torque and the steering angle are generated. Hands-off status information. The information on the hands-on or hands-off state may be generated based on an input signal from the driver to the input device, a captured image of the driver by the camera, a detection signal of a contact sensor provided on the steering wheel, and the like.

  The learning unit 71 receives the time series data of the steering torque included in the driving history and the time series data of the steering angle at the time of generation of the time series data as input signals, and outputs the latest steering torque and The hands-on or hands-off state at the time of occurrence of the steering angle is used as a teacher signal. Then, the learning unit 71 makes the determination neural network learn so that the output data matches the teacher signal. The time period of the time-series data is one second, which is the same as the time period of the time-series data used by the state determination unit 515 for determination. The learning unit 71 may use not only general-purpose driving histories of a plurality of drivers but also driving histories of specific drivers of the vehicle A for learning of the determination neural network.

  Since such a determination neural network uses not only current data of the steering torque and the steering angle but also past data as input data, it is possible to improve the determination accuracy of the hands-on state or the hands-off state. For example, when the driver switches the steering wheel 11, the torque detected by the torque sensor 21 becomes zero even if the driver is holding the steering wheel 11. In such a state, the determination neural network can determine that the state is the hands-on state because the past data before the switching is used as input data. In addition, when the driver continues to hold the steering wheel 11 with a very small steering torque, the determination neural network can determine that it is in the hands-on state because the past data is used as input data from the present. Therefore, the state determination unit 515 using the determination model formed of the determination neural network can determine the hands-on state or the hands-off state with high accuracy.

  Next, an operation of detecting a contact state of the contact state detection device 100 according to the first embodiment will be described with reference to FIGS. FIG. 6 is a flowchart illustrating an example of a contact state detection operation of contact state detection device 100 according to Embodiment 1.

  First, in step S1, the control unit 51 outputs a torque signal indicating a torque generated in the torsion bar 5ac and an angle signal indicating a rotation angle generated in the steering shaft 5 from the torque sensor 21 and the rotation angle sensor 22, respectively. To get. The control unit 51 acquires a signal detected by the torque sensor 21 and the rotation angle sensor 22 in each sensing cycle. An example of the sensing cycle is 1 ms.

  Next, in step S2, the first filter 511 removes high-frequency components from the obtained torque signal, and in step S3, the removed torque signal is used as, for example, data of the torque value T (k) in the first storage unit 513. To be stored. Similarly, the second filter 512 removes high-frequency components from the acquired angle signal in step S2, and in step S3, uses the removed angle signal as data of, for example, an angle value θ (k) in the second storage unit. 514. The torque value T (k) corresponds to the angle value θ (k), and is a torque value generated when the angle value θ (k) is generated. As described above, the acquired torque signal and angle signal are accumulated after being subjected to the low-pass filter processing.

  Next, in step S4, the state determination unit 515 obtains the time series data of the torque value from the first storage unit 513, obtains the time series data of the angle value from the second storage unit 514, and determines the determination model. Input to the neural network. The time-series data of the torque value is time-series data detected during a period from the detection of the torque value T (k) to one second of a predetermined period, and the torque values T (k) to T (kn). Data. The time-series data of the angle value is time-series data detected during a period from the detection of the angle value θ (k) to one second of the predetermined period, and the angle values θ (k) to θ (kn). Data.

  Next, in step S5, the determination neural network outputs a determination result of the hands-on state or the hands-off state, which is output data with respect to the input data, and the state determination unit 515 outputs the determination result to the motor control unit 517. The motor control unit 517 implements steering assist when in the hands-on state, and stops steering assist when in the hands-off state.

  As described above, the contact state detection device 100 according to the first embodiment detects the contact state of the steering wheel 11 as the steering member of the vehicle steering device 1. The contact state detection device 100 calculates using a torque sensor 21 as a torque detection unit that detects torque generated in the steering shaft 5 as a steering member, and input data composed of a plurality of detection values of the torque sensor 21. Accordingly, a state determination unit 515 as a calculation unit that outputs information indicating a hands-on state or a hands-off state with respect to the steering wheel 11 is provided.

  According to the above configuration, the state determination unit 515 determines the hands-on state or the hands-off state using not only the detected value of one torque but also the detected values of a plurality of torques. By using a plurality of detected torque values, the state of the steering torque can be detected with high accuracy. For example, the detected values of the plurality of torques may indicate the behavior of the torque. In the determination using the detected value of one torque, an erroneous determination of the hands-on state or the hands-off state may occur. In the determination using the behavior of the torque, since the determination based on the behavior of the torque in the hands-on state and the behavior of the torque in the hands-off state can be performed, highly accurate determination is possible. Therefore, the contact state detection device 100 can improve the detection accuracy of the contact state with the steering wheel 11.

  Further, in contact state detection device 100 according to Embodiment 1, the plurality of detection values of torque sensor 21 may be time-series data. According to the above configuration, the detected values of the plurality of torques can indicate the behavior of the torque over time. In the determination using the time-dependent behavior of the torque, it is possible to make a determination based on the time-dependent behavior of the hands-on state torque and the time-dependent behavior of the hands-off state torque, so that highly accurate determination is possible.

  Further, the contact state detection device 100 according to Embodiment 1 further includes a rotation angle sensor 22 as a rotation amount detection unit that detects the rotation amount of the steering wheel 11, and the state determination unit 515 Data composed of a detected value and a plurality of detected values of the rotation angle sensor 22 may be used as input data. According to the above configuration, the state determination unit 515 determines the hands-on state or the hands-off state using not only the detected values of the plurality of torques but also the detected values of the plurality of steering angles. That is, since the state determination unit 515 determines using the two states of the steering member including the steering wheel 11 and the steering shaft 5, highly accurate determination is possible.

  In the first embodiment, the contact state detection device 100 determines the hands-on state or the hands-off state using the detected values of the plurality of torques and the detected values of the plurality of steering angles, but is not limited thereto. The contact state detection device 100 may determine the hands-on state or the hands-off state using only the detected values of the plurality of torques. In the hands-on state, torque is often generated on the steering shaft 5. For this reason, a highly accurate determination is possible even with a determination using only a plurality of detected values of torque.

  Further, in contact state detection device 100 according to Embodiment 1, the plurality of detection values of rotation angle sensor 22 may be time-series data. According to the above configuration, the detected values of the plurality of steering angles can indicate the behavior of the steering angles over time. By using the time-dependent behavior of the steering angle, it is possible to make a determination based on the time-dependent behavior of the steering angle in the hands-on state and the time-dependent behavior of the steering angle in the hands-off state. is there.

  Further, in contact state detection device 100 according to Embodiment 1, state determination section 515 may be configured by a neural network. According to the above configuration, flexible and highly accurate determination processing in the state determination unit 515 can be easily realized.

  In addition, the contact state detection device 100 according to Embodiment 1 further includes a first filter 511 and a second filter 512 as a filter unit that applies a low-pass filter to the detection value. May be used as the input data. According to the above configuration, noise and detection values due to erroneous detection are removed from the input data. Therefore, the determination accuracy of the state determination unit 515 improves.

[Embodiment 2]
The contact state detection device 200 according to the second embodiment differs from the first embodiment in the output of the state determination unit 2515 of the control unit 251. Hereinafter, the second embodiment will be described focusing on differences from the first embodiment, and a description of the same points as the first embodiment will be omitted.

  The configuration of the contact state detection device 200 according to Embodiment 2 will be described with reference to FIGS. FIG. 7 is a block diagram illustrating an example of a functional configuration of a contact state detection device 200 according to Embodiment 2. FIG. 8 is a diagram illustrating an example of a processing flow of each component of the contact state detection device 200 according to the second embodiment. The contact state detection device 200 includes a torque sensor 21, a rotation angle sensor 22, and an ECU 50. The ECU 50 includes a control unit 251, a drive circuit 52, and a current detection unit 53. The control unit 251 includes a first filter 511, a second filter 512, a first storage unit 513, a second storage unit 514, a state determination unit 2515, a storage unit 516, a motor control unit 517, and a determination unit. 2518.

  State determination unit 2515 outputs a determination result using a determination model, as in the first embodiment. State determination unit 2515 outputs a determination result to determination unit 2518. When the same input data as in the first embodiment is input, the determination model in the second embodiment outputs a numerical value indicating the probability of the hands-on state and the hands-off state. Specifically, the determination model outputs a numerical value between “0” and “1”. When the output value is “1”, the probability of the hands-on state is 100%, and when the output value is “0”, the probability of the hands-off state is 100%. As the output value approaches "1", the probability of the hands-on state increases, and as the output value approaches "0", the probability of hands-off increases. The decision model is composed of a decision neural network. Such a determination neural network can be constructed in the same manner as in the first embodiment by using the input signal as the steering torque and the steering angle and the teacher signal as the probability of the hands-on state. Here, the output value is an example of information indicating a hands-on state or a hands-off state for the steering member.

  The determination unit 2518 determines a hands-on state or a hands-off state for the output value acquired from the state determination unit 2515. When the output value is larger than the threshold value, the determination unit 2518 determines that the hand-on state is set. Note that the determination unit 2518 may consider the duration of the output value. If the state in which the output value is larger than the threshold value continues for a predetermined time or more, the determination unit 2518 may determine that it is in the hands-on state, and otherwise, determine that it is in the hands-off state. The determination unit 2518 outputs a determination result to the motor control unit 517. An example of the threshold is a value of 0.5 or more. An example of the predetermined time is a time of one second or more. Here, the determination unit 2518 is an example of a determination unit.

  Other configurations and operations of the contact state detection device 200 according to the second embodiment are the same as those in the first embodiment, and thus description thereof will be omitted. Further, according to the contact state detection device 200 according to the second embodiment, the same effects as those of the first embodiment can be obtained.

  Further, contact state detecting apparatus 200 according to Embodiment 2 determines a hands-on state or a hands-off state based on a comparison result between a value indicated by hands-on state or hands-off state information output by state determination section 2515 and a threshold. A determining unit 2518 as a determining unit may be further provided. According to the above configuration, even when the state determination unit 2515 does not determine the hands-on state or the hands-off state and outputs a value indicating the hands-on state or the hands-off state, the determination unit 2518 determines the hands-on state or the hands-off state. For this reason, even when a different threshold value is set for each vehicle, it is not necessary to change the judgment model having a large calculation amount, and the same judgment model can be used. Therefore, the versatility of the contact state detection device 200 is improved.

  Further, in the contact state detection device 200 according to Embodiment 2, the determining unit 2518 determines the hands-on state when the state indicated by the information of the hands-on state or the hands-off state is larger than the threshold for a predetermined time or more, In other cases, the hands-off state may be determined. According to the above configuration, the hands-on state and the hands-off state are not instantaneous but continue for a certain period of time, so that the determination unit 2518 can determine the hands-on state and the hands-off state with high accuracy.

[Embodiment 3]
The contact state detection device 300 according to the third embodiment differs from the first embodiment in the input of the state determination unit 3515 of the control unit 351. Hereinafter, the third embodiment will be described focusing on points different from the first and second embodiments, and a description of the same points as the first or second embodiment will be omitted.

  The configuration of the contact state detecting device 300 according to the third embodiment will be described with reference to FIGS. FIG. 9 is a block diagram illustrating an example of a functional configuration of a contact state detection device 300 according to Embodiment 3. FIG. 10 is a diagram showing an example of a processing flow of each component of the contact state detection device 300 according to Embodiment 3. The contact state detection device 200 includes a torque sensor 21, a rotation angle sensor 22, and an ECU 50. The ECU 50 includes a control unit 351, a drive circuit 52, and a current detection unit 53. The control unit 351 includes an estimation unit 3519, a storage unit 3513, a state determination unit 3515, a storage unit 516, and a motor control unit 517.

  The estimation unit 3519 estimates the driver torque applied to the steering wheel 11 by the driver using the torque detected by the torque sensor 21 and the rotation angle detected by the rotation angle sensor 22. Further, the estimation unit 3519 stores the estimated driver torque in the storage unit 3513 in association with the detection time of the torque and the rotation angle. The stored driver torque data includes the driver torque value and the detection time. The torque detected by the torque sensor 21 may include a load torque which is an external force from a road surface, in addition to a torque resulting from a steering input from a driver. Further, when the driver switches the steering wheel 11, the torque detected by the torque sensor 21 becomes zero even if the driver is holding the steering wheel 11. The estimating unit 3519 estimates the driver torque, which is the torque applied to the steering wheel 11 by the driver, by removing the above elements.

  Since the method of estimating the driver torque is described in Patent Document 2, the details thereof will be omitted. According to Patent Literature 2, the driver torque is detected using the torque detected by the torque sensor 21 and the rotation angle and the angular velocity of the rotor of the motor 8 detected by a rotation sensor such as a resolver. The rotation angle of the rotor of the motor 8 corresponds to the steering angle detected by the rotation angle sensor 22. For this reason, in the present embodiment, the estimation unit 3519 estimates the driver torque using the torque of the torque sensor 21, the rotation angle of the rotation angle sensor 22, and the angular velocity thereof.

  The configuration of the storage unit 3513 is the same as the first storage unit 513 and the second storage unit 514 of the first embodiment. The storage unit 3513 stores data of a plurality of driver torques estimated by the estimation unit 3519. Specifically, the storage unit 3513 stores the time series data of the driver torque value.

  State determination unit 3515 outputs a determination result using a determination model, as in the first embodiment. State determination unit 3515 outputs a determination result to motor control unit 517. The determination model according to the third embodiment uses time-series data of the driver torque value of storage unit 3513 as input data, and outputs the same output data as that of the first embodiment, that is, a determination result of a hands-on state or a hands-off state. Specifically, the state determination unit 3515 determines the driver torque value Td (k) detected during the period from the detection time of the latest driver torque value Td (k) estimated by the estimation unit 3519 to one second of the predetermined period. ) To Td (kn) are acquired from the storage unit 3513. The determination model of the state determination unit 3515 receives driver torque values Td (k) to Td (kn) as input data and outputs output data indicating a hands-on state or a hands-off state. The decision model is composed of a decision neural network. Such a determination neural network can be constructed in the same manner as in the first embodiment by using the input signal as the driver torque and the teacher signal as the determination result of the hands-on state or the hands-off state.

  Other configurations and operations of the contact state detection device 300 according to the third embodiment are the same as those of the first embodiment, and thus description thereof will be omitted. Further, according to the contact state detection device 300 according to the third embodiment, the same effect as that of the first embodiment can be obtained.

  Further, the contact state detection device 300 according to Embodiment 3 further includes an estimation unit 3519 for estimating a driver torque applied to the steering wheel 11 by the driver. The estimation unit 3519 includes a plurality of detection values of the torque sensor 21 and A plurality of estimated values of the driver torque based on a plurality of detected values of the rotation angle sensor 22 are estimated, and the state determination unit 3515 may use data composed of the plurality of estimated values as input data. According to the above configuration, the estimation unit 3519 can highly accurately estimate a steering input applied to the steering wheel 11 by the driver as a driver torque. Then, the state determination unit 3515 determines the hands-on state or the hands-off state using such driver torque as input data, so that highly accurate determination is possible.

  Further, the contact state detection device 300 according to the third embodiment includes a first filter that removes a high-frequency component of a detection signal output from the torque sensor 21 and the rotation angle sensor 22 to the estimation unit 3519 as in the first embodiment. 511 and a second filter 512 may be provided. Thus, the accuracy of estimating the driver torque by the estimating unit 3519 can be improved.

  Further, the contact state detection device 300 according to the third embodiment may include a determination unit as in the second embodiment. In this case, the state determination unit 3515 may output a numerical value indicating the probability of the hands-on state and the hands-off state using the driver torque as input data.

[Others]
As described above, the contact state detecting device and the like according to one or more aspects of the present invention have been described based on the embodiments, but the present invention is not limited to the embodiments. Various modifications conceivable by those skilled in the art may be applied to the present embodiment, and a form constructed by combining components in different embodiments may be one or more aspects of the present invention, without departing from the spirit of the present invention. May be included in the range.

  For example, in the contact state detection device according to the embodiment, the state determination unit determines a plurality of detection values detected by one torque sensor 21 and a plurality of detection values detected by one rotation angle sensor 22. Although the input data is used, the present invention is not limited to this. The state determination unit may use, as input data, a plurality of detection values detected by the plurality of torque sensors and a plurality of detection values detected by the plurality of rotation angle sensors. When the arrangement positions of the plurality of torque sensors are different, the detection values of the respective torque sensors may be different. The detection value of each rotation angle sensor may be different due to the different arrangement positions of the plurality of rotation angle sensors. The determination model of the state determination unit can perform highly accurate determination by using various data as input data. As described above, the state determination unit may use, as input data, a plurality of detection values detected by one or more torque sensors and a plurality of detection values detected by one or more rotation angle sensors.

  In the contact state detection device according to the embodiment, the state determination unit uses the plurality of detection values detected by the torque sensor 21 and the plurality of detection values detected by the rotation angle sensor 22 as input data. However, the present invention is not limited to this. For example, the state determination unit may use only a plurality of detection values detected by the torque sensor 21 as input data. In the hands-on state, torque is often generated on the steering shaft 5. The detection value of the torque sensor 21 may reflect the hands-on state more than the detection value of the rotation angle sensor 22. For this reason, highly accurate determination is possible even in the determination of the state determination unit using only the detected values of the plurality of torques.

  Further, the contact state detecting device according to the embodiment is provided in the vehicle steering device 1 in which the steering mechanism and the turning mechanism are mechanically connected, but is not limited thereto. The vehicle steering system including the contact state detection device may constitute a steer-by-wire system in which the steering mechanism and the steering mechanism are not mechanically connected. Further, the vehicle steering system may constitute a steer-by-wire system capable of left-right independent steering. In the steer-by-wire system, the steering mechanisms of the left and right steered wheels are not mechanically coupled to each other, and are not mechanically coupled to the steering mechanism. The left and right steering mechanisms are operated by actuators provided in each steering mechanism.

  Further, the contact state detecting device according to the embodiment is mounted on a vehicle, but is not limited to this, and may be mounted on any device or the like including a steering member. For example, the contact state detection device may be mounted on a ship or an aircraft.

  In the embodiment, the determination results of the hands-on state and the hands-off state of the state determination unit of the contact state detection device may be used for any purpose. For example, when the vehicle A has an automatic driving function, the determination result of the state determining unit may be used for operation and non-operation of the automatic driving function, that is, for ON / OFF control. For example, when the state determination unit determines the hands-on state during the automatic driving, the automatic driving function may be turned off. Alternatively, a warning may be issued when the state determination unit determines the hands-off state for a certain period or more during the manual operation. The automatic driving function may include a partial automatic driving function that assists the driver in driving, and a fully automatic driving function in which the driver's actions such as operation and determination do not intervene.

  Further, as described above, the technology of the present invention may be realized by a recording medium such as a system, an apparatus, a method, an integrated circuit, a computer program or a computer-readable recording disk, and the system, the apparatus, the method, and the integrated circuit. , A computer program and a recording medium. The computer-readable recording medium includes, for example, a non-volatile recording medium such as a CD-ROM.

  For example, each processing unit included in the above embodiment is typically realized as an LSI (Large Scale Integration), which is an integrated circuit. These may be individually formed into one chip, or may be formed into one chip so as to include some or all of them.

  Further, the integrated circuit is not limited to the LSI, and may be realized by a dedicated circuit or a general-purpose processor. An FPGA (Field Programmable Gate Array) that can be programmed after manufacturing the LSI, or a reconfigurable processor that can reconfigure the connection and setting of circuit cells inside the LSI may be used.

  In the above-described embodiment, each component may be configured by dedicated hardware or may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a processor such as a CPU reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory.

  In addition, a part or all of the above components may be configured by a removable IC (Integrated Circuit) card or a single module. The IC card or the module is a computer system including a microprocessor, a ROM, a RAM, and the like. The IC card or the module may include the above-described LSI or system LSI. The IC card or module achieves its functions by the microprocessor operating according to the computer program. These IC cards and modules may have tamper resistance.

  The contact state detection method of the present invention is, for example, a contact state detection method for detecting a contact state of a steering member of a vehicle steering device with a plurality of detection values of a torque generated in the steering member. By using input data composed of a plurality of detected values of the torque, information indicating a hands-on state or a hands-off state with respect to the steering member is output. Such a contact state detection method may be realized by a processor such as an MPU (Micro Processing Unit) and a CPU, a circuit such as an LSI, an IC card or a single module, or the like.

  Further, the technology of the present invention may be realized by a software program or a digital signal including the software program, or may be a non-temporary computer-readable recording medium on which the program is recorded. For example, such a program obtains a plurality of detected values of a torque generated in a steering member of a vehicle steering device, and calculates by using input data constituted by a plurality of detected values of the torque, thereby obtaining the aforementioned program. And causing the computer to output information indicating a hands-on state or a hands-off state for the steering member.

  Further, the numbers such as the ordinal numbers and the quantities used above are all examples for specifically explaining the present invention, and the present invention is not limited to the illustrated numbers. Further, the connection relation between the constituent elements is illustrated for specifically describing the present invention, and the connection relation for realizing the function of the present invention is not limited to this.

  The division of functional blocks in the block diagram is merely an example, and a plurality of functional blocks can be implemented as one functional block, one functional block can be divided into a plurality of functional blocks, and some functions can be transferred to other functional blocks. You may. Also, the functions of a plurality of functional blocks having similar functions may be processed by a single piece of hardware or software in parallel or time division.

  The contact state detecting device according to the present invention is useful for a device including a steering member.

  Reference Signs List 1 vehicle steering device, 5 steering shaft (steering member), 11 steering wheel (steering member), 21 torque sensor (torque detecting unit), 22 rotation angle sensor (rotation amount detecting unit), 51, 251 and 351 control unit, 100, 200, 300 Contact state detection device, 511 First filter (filter unit), 512 Second filter (filter unit), 515, 2515, 3515 State determination unit (calculation unit), 2518 Determination unit (determination unit), 3519 Estimator, vehicle A

Claims (11)

A contact state detection device that detects a contact state of a steering device for a vehicle with a steering member,
A torque detector that detects a torque generated in the steering member;
A contact unit for calculating information using input data composed of a plurality of detection values of the torque detecting unit, thereby outputting information indicating a hands-on state or a hands-off state for the steering member. The contact state detection device according to claim 1, wherein the plurality of detection values of the torque detection unit are time-series data. Further provided is a rotation amount detection unit that detects a rotation amount of the steering member,
3. The contact state detection device according to claim 1, wherein the calculation unit uses, as the input data, data configured by a plurality of detection values of the torque detection unit and a plurality of detection values of the rotation amount detection unit. 4. . The contact state detection device according to claim 3, wherein the plurality of detection values of the rotation amount detection unit are time-series data. A rotation amount detection unit that detects a rotation amount of the steering member,
An estimating unit that estimates a driver torque applied to the steering member by a driver,
The estimation unit estimates a plurality of estimated values of the driver torque based on a plurality of detection values of the torque detection unit and a plurality of detection values of the rotation amount detection unit,
The contact state detection device according to any one of claims 1 to 4, wherein the calculation unit uses data composed of the plurality of estimated values as the input data. The contact according to any one of claims 1 to 5, further comprising: a determination unit configured to determine the hands-on state or the hands-off state based on a comparison result between a value indicated by the information output by the calculation unit and a threshold. State detection device. The contact according to claim 6, wherein the determination unit determines the hands-on state when a state in which the value indicated by the information is greater than the threshold continues for a predetermined time or more, and otherwise determines the hands-off state. State detection device. The contact state detection device according to any one of claims 1 to 7, wherein the calculation unit includes a neural network. Further comprising a filter unit that applies a low-pass filter to the detection value,
The contact state detection device according to any one of claims 1 to 8, wherein the calculation unit uses data constituted by the detection values after the application of the low-pass filter as the input data. A contact state detection method for detecting a contact state of a steering member for a vehicle with a steering member,
Obtain a plurality of detection values of torque generated in the steering member,
A contact state detection method for outputting information indicating a hands-on state or a hands-off state with respect to the steering member by calculating using input data including a plurality of detected values of the torque. Obtain a plurality of detected values of torque generated in the steering member of the vehicle steering device,
A program for causing a computer to output information indicating a hands-on state or a hands-off state for the steering member by calculating using input data composed of a plurality of detected values of the torque.

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