Steering wheel hands-on detection device

Abstract

To provide a hands on determination system of a steering wheel capable of inhibiting erroneous determination.SOLUTION: A hands on determination system of a steering wheel includes onboard sensors including a sensor for detecting a torque applied to a steering wheel, and a processor that, when the torque exceeds a torque threshold, determines that a hands on condition where a driver holds the steering wheel is established. The onboard sensors include a sensor for acquiring information on a posture of a vehicle body of a self vehicle. When it is determined based on the information acquired from the sensor that the current posture of the vehicle body is a predetermined reference posture and consistent with a posture attained when the vehicle is halted on an even road surface, the processor allocates a predetermined standard value to the torque threshold. When it is determined that the current posture of the vehicle body is different from the reference posture, the processor allocates a predetermined value larger than the standard value to the torque threshold.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a hands-on determination device for a steering wheel that determines whether a driver is gripping the steering wheel of his / her own vehicle.

Background Art

[0002] There has been proposed a driving support device that supports a driver's driving operation when a predetermined condition is satisfied. For example, the driving support device includes an ADTJA function (ADTJA = Advanced Drive Traffic Jam Assist) that advances the host vehicle along the driving lane when a traffic jam occurs on an expressway or an automobile exclusive road. When a predetermined hands-off condition is satisfied under a situation where the ADTJA function is enabled, the driver is allowed to release his / her hand from the steering wheel (hands-off). When the hands-off condition becomes not satisfied in the hands-off state (for example, when the driving support device detects that the driver is not paying attention to the front, when the driving support device cannot recognize the lane mark (the dividing line of the driving lane), etc.), the driving support device issues an alarm to prompt the driver to grip the steering wheel (hands-on). Then, when the driving support device detects that the driver has gripped the steering wheel, the alarm is terminated.

[0003] The above driving support device includes a device (a hands-on determination device for a steering wheel) that determines whether a driver is gripping the steering wheel. (For example, refer to Patent Document 1 below). This device (hereinafter referred to as a conventional device) includes a sensor that detects an external force (torque) for rotating the steering wheel. The conventional device determines that the driver is gripping the steering wheel when the output value of the sensor exceeds a threshold value. In this specification, "grip" and "hands-on" mean a state in which the driver touches the steering wheel so that he / she can immediately start steering.

Prior Art Documents

Patent Documents

[0004] [Patent Document 1] Japanese Patent Publication No. 2019-14468 [Overview of the Initiative]

[0005] Incidentally, when the vehicle accelerates (decelerates) and / or turns, inertial forces act on the vehicle body, causing pitching (vertical oscillation), rolling (lateral oscillation), etc. (hereinafter referred to as "posture loss"). For example, when the vehicle is decelerating, pitching (nose dive) occurs, where the front end of the vehicle body drops slightly, due to the inertial force acting on the vehicle towards the front. In this case, when hands-off, the rotation of the steering wheel is not restricted. Therefore, due to the deterioration of the vehicle body's posture, the steering wheel rotates slightly, and the output value (torque value) of the steering wheel sensor increases, which may temporarily exceed the threshold. In this case, even though the steering wheel is not being gripped, the conventional device may misjudge that the steering wheel is being gripped.

[0006] One of the objectives of the present invention is to provide a hands-on steering wheel judgment device that can suppress misjudgments.

[0007] To solve the above problems, the hands-on determination device (1) for the steering wheel of the present invention is: An on-board sensor (20) includes a steering sensor (22) for detecting the torque (τs) applied to the steering wheel (SW), A processor (10) determines that the driver is in a hands-on state, holding the steering wheel, when the torque exceeds a torque threshold (τsth), It is equipped with. The on-board sensor includes attitude sensors (21, 23, 24) for acquiring information (αx, αy, G, YR) regarding the attitude of the vehicle body, Based on the information obtained from the attitude sensor, the processor When it is determined that the current posture of the vehicle body is a predetermined reference posture and matches the posture of the vehicle when it is stationary on a level road surface, a predetermined standard value (τ0) is assigned to the torque threshold. If it is determined that the current posture of the vehicle body is different from the reference posture, a predetermined value (τ1, τ2, τ3) greater than the standard value is assigned to the torque threshold. It is configured in this way.

[0008] Furthermore, the hands-on determination method for the steering wheel according to the present invention is A torque detection step that detects the torque applied to the steering wheel, A determination step in which, if the torque exceeds a torque threshold, it is determined that the driver is in a hands-on state, gripping the steering wheel; Includes. This includes a posture information acquisition step that acquires information about the attitude of the vehicle body, The aforementioned determination step is performed based on the information obtained in the posture information acquisition step, When it is determined that the current posture of the vehicle body is a predetermined reference posture and matches the posture of the vehicle when it is stationary on a level road surface, a predetermined standard value is assigned to the torque threshold. If it is determined that the current posture of the vehicle body is different from the reference posture, a predetermined value greater than the standard value is assigned to the torque threshold. Includes a threshold setting step.

[0009] Furthermore, the hands-on determination program for the steering wheel according to the present invention is The computer installed in the vehicle, A torque detection step that detects the torque applied to the steering wheel, A determination step in which, if the torque exceeds a torque threshold, it is determined that the driver is in a hands-on state, gripping the steering wheel; Make it run. The determination step includes an attitude information acquisition step that acquires information regarding the attitude of the vehicle body, The aforementioned determination step is performed based on the information obtained in the posture information acquisition step, When it is determined that the current posture of the vehicle body is a predetermined reference posture and matches the posture of the vehicle when it is stationary on a level road surface, a predetermined standard value is assigned to the torque threshold. If it is determined that the current posture of the vehicle body is different from the reference posture, a predetermined value greater than the standard value is assigned to the torque threshold. Includes a threshold setting step.

[0010] As described above, it is conceivable that in a specific scenario (hereinafter referred to as the "specific scenario"), the steering wheel may rotate slightly due to a change in the vehicle's posture while the driver is not gripping the steering wheel, causing an increase in the output value of the steering sensor (detected torque value). According to the present invention, the torque threshold is raised when the vehicle's posture differs from the standard posture (when a change in the vehicle's posture occurs). Therefore, in the specific scenario, the output value of the steering sensor is less likely to exceed the torque threshold compared to when the torque threshold is not raised. As a result, in the specific scenario, it is suppressed that the system may incorrectly determine that the driver is gripping the steering wheel when they are not (misjudgment).

[0011] In a hands-on determination device for a steering wheel according to one aspect of the present invention, When the processor detects that pitching is occurring in the vehicle body, it assigns a predetermined first torque value (τ1) to the torque threshold.

[0012] According to the hands-on determination device for a steering wheel according to this aspect, when the front end side of the host vehicle is inclined so as to be positioned below or above the rear end side, the torque threshold value is raised. As a result, in a specific scene, it is more difficult for the output value of the steering sensor to exceed the torque threshold value than when the torque threshold value is not raised. Therefore, in a specific scene, it is possible to suppress the occurrence of a situation (false determination) in which it is determined that the driver is holding the steering wheel even though the driver is not holding the steering wheel.

[0013] In the hands-on determination device for a steering wheel according to another aspect of the present invention, When the processor detects that rolling has occurred in the vehicle body, the processor assigns a second torque value (τ2) to the torque threshold value.

[0014] According to the hands-on determination device for a steering wheel according to this aspect, when the right end side (left end side) of the host vehicle is inclined so as to be positioned below the left end side (right end side) (a scene in which rolling has occurred), the torque threshold value is raised. As a result, in a specific scene, it is more difficult for the output value of the steering sensor to exceed the torque threshold value than when the torque threshold value is not raised. Therefore, in a specific scene, it is possible to suppress the occurrence of a situation (false determination) in which it is determined that the driver is holding the steering wheel even though the driver is not holding the steering wheel.

Brief Description of Drawings

[0015] [Figure 1] FIG. 1 is a block diagram of a hands-on determination device for a steering wheel according to an embodiment of the present invention. [Figure 2] FIG. 2 is a time chart showing a first operation example of the hands-on determination device for the steering wheel of FIG. 1. [Figure 3] FIG. 3 is a time chart showing a second operation example of the hands-on determination device for the steering wheel of FIG. 1. [Figure 4]FIG. 4 is a flowchart of a program for realizing a hands-on determination function.

Embodiments for Carrying Out the Invention

[0016] (Schematic) As shown in FIG. 1, a hands-on determination device 1 for a steering wheel according to an embodiment of the present invention (hereinafter referred to as the hands-on determination device 1) is applied to a vehicle V (hereinafter referred to as the "host vehicle") equipped with an automatic driving function and a driving support function. As one of the driving support functions, the above ADTJA function is included. The hands-on determination device 1 determines whether the driver is gripping the steering wheel in a state where the automatic driving function is disabled and the ADTJA function is enabled, and provides the determination result to the driving support device.

[0017] (Specific Configuration) As shown in FIG. 1, the hands-on determination device 1 includes an ECU 10 and an in-vehicle sensor 20.

[0018] The ECU 10 includes a microcomputer including a CPU 10a, a ROM 10b (rewritable non-volatile memory), a RAM 10c, a timer 10d, etc. The CPU realizes various functions by executing a program (instruction) stored in the ROM. The ECU 10 is connected to other ECUs (for example, an ECU that executes driving support (warning, automatic braking, etc.)) via a CAN (Controller Area Network).

[0019] The in-vehicle sensor 20 includes an acceleration sensor 21 and a steering sensor 22.

[0020] The acceleration sensor 21 detects and outputs the acceleration αx in the longitudinal direction of the host vehicle and the acceleration αy in the width direction of the host vehicle. The acceleration sensor 21 provides the acceleration αx and the acceleration αy to the ECU 10.

[0021] The steering sensor 22 detects and outputs the absolute value (hereinafter referred to as "torque value τs") of the external force (torque) that rotates the steering wheel switch based on the twist angle of the torsion bar connected to the steering wheel switch. The steering sensor 22 provides this detected value to the ECU 10. The steering sensor 22 has sufficient sensitivity to detect even a small amount of torque applied to the steering wheel switch by the driver lightly gripping the steering wheel switch. Furthermore, the steering sensor 22 has sufficient sensitivity to detect even a small amount of torque generated in the steering wheel switch when the vehicle accelerates and / or turns, even when the steering wheel switch is not being gripped.

[0022] (Hands-on detection function) When the ADTJA function is enabled, the ECU 10 sequentially acquires the torque value τs from the steering sensor 22. The ECU 10 determines that the driver is not gripping the steering wheel switch (hands off) if the torque value τs is less than or equal to the threshold τsth. In this case, the ECU 10 sets the hands-on flag HF to "0". On the other hand, the ECU 10 determines that the driver is gripping the steering wheel switch (hands-on) if the torque value τs exceeds the threshold τsth. In this case, the ECU 10 sets the hands-on flag HF to "1". The ECU 10 responds to a request from the driver assistance system's ECU (hereinafter referred to as "ADTJA-ECU") and provides the hands-on flag HF (the value assigned to the hands-on flag HF) to the ADTJA-ECU. For example, when the hands-off condition is no longer met in the hands-off state (for example, when the driver is not paying attention to the road ahead, or when lane markings are no longer recognized), the ADTJA-ECU acquires the value of the hands-on flag HF from the hands-on detection device 1 at predetermined intervals. If the hands-on flag HF acquired from the hands-on detection device 1 is "0", the ADTJA-ECU controls the notification device installed in the vehicle so that predetermined information (hands-on warning) is presented to the driver.

[0023] Here, the ECU10 determines the torque value to be assigned to the threshold τsth as follows.

[0024] Based on the information obtained from the acceleration sensor 21, the ECU 10 determines whether or not the vehicle's posture is unstable (pitching and / or rolling). Specifically, if the absolute value of acceleration αx is less than or equal to the threshold αxth, and the absolute value of acceleration αy is less than or equal to the threshold αyth, the ECU 10 determines that the vehicle's posture is consistent with the standard posture (the posture of the vehicle when it is stationary on a level road surface). In other words, in this case, the ECU 10 determines that the vehicle's posture is not unstable (pitching and rolling). In this case, the ECU 10 assigns a predetermined standard torque value τ0 to the threshold τsth.

[0025] On the other hand, ECU10 determines that a vehicle's posture is unstable if the absolute value of acceleration αx exceeds the threshold αxth, and / or the absolute value of acceleration αy exceeds the threshold αyth. ECU10 assigns a torque value τ1 greater than the torque value τ0 to the threshold τsth if acceleration αx exceeds the threshold αxth and acceleration αy is less than or equal to the threshold αyth. ECU10 also assigns a torque value τ2 greater than the torque value τ0 to the threshold τsth if the absolute value of acceleration αx is less than or equal to the threshold αxth and acceleration αy exceeds the threshold αyth. ECU10 also assigns a torque value τ3 greater than the torque value τ0 to the threshold τsth if the absolute value of acceleration αx exceeds the threshold αxth and acceleration αy exceeds the threshold αyth. Here, the torque values ​​τ1, τ2, and τ3 are greater than the torque value τa and less than the torque value τb shown below. Torque value τa… The maximum torque applied to the steering wheel switch due to the loss of vehicle posture caused by the automatic acceleration (deceleration) and / or turning of the vehicle by the ADTJA function while hands-off. Torque value τb... The torque value applied to the steering wheel switch by the driver lightly gripping the steering wheel switch. The torque values ​​τa and τb are determined experimentally. The relative magnitudes of the torque values ​​τ1, τ2, and τ3 can be arbitrarily set (for example, according to the pitch stiffness and roll stiffness of the vehicle (model)). Furthermore, the torque values ​​τ0, τ1, τ2, and τ3 may be fixed values, or the torque values ​​τ0 and τ1 may be adjustable by the user.

[0026] Next, referring to Figures 2 and 3, we will explain an example of the operation of the hands-on determination device 1 (changes in threshold τsth and hands-on flag HF) in a scenario where the ADTJA function is enabled and the hands-off condition is not met (a scenario where the driver must hold the steering wheel SW). Note that throughout the entire period of these examples, no rolling occurs in the vehicle body (αy ≤ αyth).

[0027] (Example of operation 1) As shown in Figure 2, in the operation example 1, for example, the vehicle automatically brakes (ADTJA function) because the distance between the vehicle and the preceding vehicle falls below a threshold. The driver is not gripping the steering wheel SW at time t0. Also, at time t0, the absolute value of acceleration αx (hereinafter simply referred to as "acceleration αx") is less than or equal to the threshold αxth. Therefore, at time t0, the ECU 10 determines that the vehicle's attitude has not deteriorated (nose dive) and assigns the torque value τ0 to the threshold τsth.

[0028] Furthermore, at the time t0, the steering wheel switch is not being held (hands off), and the vehicle's posture is not unstable (the posture is only slightly unstable (αx≦αxth)). Therefore, the rotational angle position of the steering wheel switch is approximately at the neutral position, and the output value (torque value τs) of the steering sensor 22 is less than or equal to the threshold τsth (=τs0). Consequently, the ECU 10 determines that the driver is not holding the steering wheel switch (hands off). In this case, the ECU 10 sets the hands-on flag HF to "0". In this case, the ADTJA-ECU causes the notification device to execute a predetermined hands-on warning. As a hands-on warning, the notification device presents images, sounds, etc., to encourage the driver to hold the steering wheel switch. More specifically, the notification device displays an image (icon) resembling a steering wheel and plays the phrase, "Please hold the steering wheel." Once the notification device has finished playing the phrase, it will erase the steering wheel image (icon) that was displayed.

[0029] As described above, at time t0, information (image and sound) prompting the driver to grip the steering wheel switch is presented, but the vehicle continues to move without the driver gripping the steering wheel switch. In other words, during the period T1 from time t0 to the subsequent time t1, the driver is not gripping the steering wheel (hands off). Also, during period T1, there is no deformation of the vehicle's body posture (or only a slight deformation). Therefore, the rotation angle position of the steering wheel switch is approximately at the neutral position. Consequently, the output value (torque value τs) of the steering sensor 22 is less than or equal to the threshold τsth (=τ0). Therefore, during period T1, the ECU 10 sets the hands-on flag HF to "0".

[0030] From a point slightly before time t1, the acceleration αx increases, and at time t1, the acceleration αx exceeds the threshold αxth. Then, during the period after time t1, the acceleration αx is maintained at a value slightly greater than the threshold αxth. At time t1, the ECU 10 determines that the vehicle's attitude has become unstable and assigns the torque value τ1 (>τ0) to the threshold τsth. In other words, at time t1, the ECU 10 raises the threshold τsth. Also, at this time t1, the driver is not yet gripping the steering wheel SW. Therefore, due to the aforementioned instability of the vehicle's attitude, the steering wheel SW rotates slightly (starts to oscillate), and the output value (torque value τs) of the steering sensor 22 increases. The torque value τs increases somewhat later than the progression of the attitude instability (increase in acceleration αx), and reaches the torque value τa at time t2, a little after time t1. The torque value τs increases and exceeds the torque value τ0 (the value assigned to the threshold τsth in period T1), but at that point (between time t1 and time t2), the value assigned to the threshold τsth has already been raised from torque value τ0 to torque value τ1. Therefore, in period T2, spanning from time t1 to time t2, the torque value τs is less than or equal to the threshold τsth. Consequently, the ECU 10 determines that the driver is not gripping the steering wheel SW in period T2. Therefore, the hands-on flag HF remains "0" in period T2, as it was in period T1.

[0031] During the period T3, from time t2 to the subsequent time t3, the driver is not gripping the steering wheel switch (hands off), and the vehicle's attitude is unstable (nose dive). Therefore, during period T3, the rotational angle position of the steering wheel switch is the same as the rotational angle position at time t2. Consequently, the torque value τs (=τa) is less than or equal to the threshold τsth (=τs1). Therefore, the hands-on flag HF remains at "0" during period T3, just as it was during period T2.

[0032] At time t3, the driver grips the steering wheel switch. This increases the torque value τs, which exceeds the threshold τsth (=τ1) at time t4, and then reaches the torque value τb. During the period T4 from time t3 to time t4, the torque value τs is less than or equal to the threshold τsth, so during this period T4, the ECU 10 sets the hands-on flag HF to "0". During the period T5 from time t4 onward, the driver is gripping the steering wheel switch, and the torque value τs (=τb) remains above the threshold τsth (=τ1) (τb > τsth). Therefore, during the period T5, the ECU 10 sets the hands-on flag HF to "1".

[0033] (Example of operation 2) Throughout the entire period in Operation Example 2 shown in Figure 3, the vehicle is automatically braked (ADTJA function). Similar to Operation Example 1, during period T1, the driver is not gripping the steering wheel SW, and the vehicle's posture is not unstable. Therefore, during period T1, the torque value τ0 is assigned to the threshold τsth, and the torque value τs is less than or equal to the threshold τsth. Consequently, the ECU 10 sets the hands-on flag HF to "0" during period T1.

[0034] At time t1, the driver grips the steering wheel switch. That is, unlike in operation example 1, the driver grips the steering wheel switch while the vehicle's posture is not unstable (the torque value τ0 is assigned to the threshold τsth). As a result, the torque value τs increases, exceeding the threshold τsth (=τ0) at time t2, and then reaching the torque value τb. During the period T2 from time t1 to time t2, the torque value τs is less than or equal to the threshold τsth, so during this period T2, the ECU 10 sets the hands-on flag HF to "0". During the period T3 from time t2 onward, the driver is gripping the steering wheel switch, and the state in which the torque value τs exceeds the threshold τsth (=τ0) is maintained. Therefore, during this period T3, the ECU 10 sets the hands-on flag HF to "1".

[0035] The above example assumes a scenario where the vehicle is decelerating (i.e., the direction of acceleration αx is opposite to the direction of travel of the vehicle). However, even in a scenario where the vehicle is accelerating, the ECU10 compares the absolute value of acceleration αx with the threshold αxth, and sets the hands-on flag HF accordingly, similar to the above example.

[0036] Next, referring to Figure 4, we will explain the program PR1 executed by the CPU 10a of the ECU 10 (hereinafter simply referred to as "CPU") in order to implement the hands-on determination process described above.

[0037] When the ADTJA function is enabled, the CPU starts executing program PR1 at predetermined intervals. The CPU starts executing program PR1 from step 100 and proceeds to step 101.

[0038] In step 101, the CPU obtains acceleration αx from the acceleration sensor 21 and determines whether the absolute value of acceleration αx exceeds the threshold αxth. If the CPU determines that the absolute value of acceleration αx exceeds the threshold αxth (101: Yes), it proceeds to step 102. On the other hand, if the CPU does not determine that the absolute value of acceleration αx exceeds the threshold αxth (101: No), it proceeds to step 103.

[0039] In step 102, the CPU obtains the acceleration αy from the acceleration sensor 21 and determines whether the absolute value of the acceleration αy exceeds the threshold αyth. If the CPU determines that the absolute value of the acceleration αy exceeds the threshold αyth (102: Yes), it proceeds to step 107. On the other hand, if the CPU does not determine that the absolute value of the acceleration αy exceeds the threshold αyth (102: No), it proceeds to step 105.

[0040] In step 103, the CPU obtains the acceleration αy from the acceleration sensor 21 and determines whether the absolute value of the acceleration αy exceeds the threshold αyth. If the CPU determines that the absolute value of the acceleration αy exceeds the threshold αyth (103: Yes), it proceeds to step 106. On the other hand, if the CPU does not determine that the absolute value of the acceleration αy exceeds the threshold αyth (103: No), it proceeds to step 104.

[0041] In step 104, the CPU assigns torque value τ0 to the threshold τsth. In step 105, the CPU assigns torque value τ1 to the threshold τsth. In step 106, the CPU assigns torque value τ2 to the threshold τsth. In step 107, the CPU assigns torque value τ3 to the threshold τsth. Next, the CPU proceeds to step 108.

[0042] In step 108, the CPU obtains a torque value τs from the steering sensor 22 and determines whether the torque value τs exceeds a threshold τsth. If the CPU determines that the torque value τs exceeds the threshold τsth (108: Yes), it proceeds to step 109. On the other hand, if the CPU does not determine that the torque value τs exceeds the threshold τsth (108: No), it proceeds to step 110.

[0043] In step 109, the CPU sets the hands-on flag HF to "1". Next, the CPU proceeds to step 111, in which step 111 terminates the execution of program PR1.

[0044] In step 110, the CPU sets the hands-on flag HF to "0". Next, the CPU proceeds to step 111, in which step 111 terminates the execution of program PR1.

[0045] (effect) As described above, in a specific scenario, it is conceivable that the output value (torque value τs) of the steering sensor 22 increases due to a slight rotation of the steering wheel switch caused by a change in the vehicle's posture when the driver is not gripping the steering wheel switch. According to the hands-on determination device 1, when the vehicle's posture differs from the standard posture (when the vehicle's posture is unstable (for example, operation example 1 shown in Figure 2)), the threshold τsth is raised from the standard torque value τ0 to a larger torque value τ1. Therefore, in the specific scenario, the output value of the steering sensor 22 is less likely to exceed the threshold τsth compared to when the threshold τsth is not raised. As a result, in the specific scenario, it is suppressed that the device will determine that the driver is gripping the steering wheel switch when the driver is not (misjudgment).

[0046] On the other hand, if the vehicle's posture is not compromised (for example, operation example 2 shown in Figure 3), the threshold τsth is maintained at the standard torque value τ0 (the threshold τsth is not increased). Therefore, when the driver grips the steering wheel switch, the output value (torque value τs) of the steering sensor 22 is likely to exceed the threshold τsth. This suppresses the misjudgment that the driver is not gripping the steering wheel switch when they are actually gripping it.

[0047] The present invention is not limited to the embodiments described above, and various modifications can be adopted within the scope of the present invention, as described below.

[0048] <Example 1> The on-board sensor 20 may include a camera 23 as a sensor for detecting the attitude of the vehicle. The camera 23 includes an imaging device and an image analysis device. The imaging device, for example, incorporates a CCD. The imaging device is installed at the front of the vehicle and directed forward of the vehicle. Each imaging device captures a predetermined area in front of the vehicle at a predetermined frame rate and acquires image data. The image analysis device analyzes the image data acquired from the imaging device and recognizes objects present around the vehicle from the image. For example, the image analysis device recognizes other vehicles located directly in front of the vehicle, poles, lane markings (lane markings), etc. The image analysis device provides the recognition results to the ECU 10.

[0049] The ECU 10 may determine whether or not the vehicle's attitude is unstable based on the recognition results of the image G acquired from the camera 23, instead of (or in addition to) the accelerations αx and αy. For example, the ECU 10 acquires the recognition results of the image G from the camera 23 at a predetermined period. Then, the ECU 10 determines whether or not pitching has occurred in the vehicle's body based on the change in the distance (spacing) of the left and right lane lines captured in these multiple image G (time-series data). For example, the ECU 10 determines that nose dive has occurred in the vehicle's body when the distance of the lane lines in the image increases and the amount of change exceeds a threshold. Also, for example, the ECU 10 determines that rolling has occurred in the vehicle's body when the angle between the extension direction of a pole (usually an object extending vertically) captured in multiple image G (time-series data) and the vertical axis of the image G increases and exceeds a threshold.

[0050] <Modification 2> The on-board sensor 20 may include a yaw rate sensor 24 as a sensor for detecting the attitude of the vehicle. The yaw rate sensor 24 detects the yaw rate YR, which is the rate of change of the yaw angle of the vehicle, and provides the yaw rate YR to the ECU 10. The ECU 10 determines that rolling is occurring in the vehicle body when the yaw rate YR exceeds a threshold YRth. [Explanation of symbols]

[0051] 1...Steering wheel hands-on detection device, 10...ECU, 20...In-vehicle sensor

Claims

1. An in-vehicle sensor including a steering sensor for detecting the torque applied to the steering wheel, A processor that determines that the driver is in a hands-on state, holding the steering wheel, when the torque exceeds a torque threshold, A hands-on determination device for a steering wheel equipped with, The on-board sensor includes attitude sensor for acquiring information regarding the attitude of the vehicle's body, Based on the information obtained from the attitude sensor, the processor When it is determined that the current posture of the vehicle body is a predetermined reference posture and matches the posture of the vehicle when it is stationary on a level road surface, a predetermined standard value is assigned to the torque threshold. If it is determined that the current posture of the vehicle body is different from the reference posture, a predetermined value greater than the standard value is assigned to the torque threshold. When pitching is detected in the vehicle body, a predetermined first torque value is assigned as the predetermined value, and when rolling is detected in the vehicle body, at least one of the following assignments is performed: A hands-on detection device for a steering wheel configured as follows.

2. A torque detection step that detects the torque applied to the steering wheel, A determination step in which, if the torque exceeds a torque threshold, it is determined that the driver is in a hands-on state, gripping the steering wheel; A method for determining whether a steering wheel is hands-on, including, This includes a posture information acquisition step that acquires information about the attitude of the vehicle body, The aforementioned determination step is performed based on the information obtained in the posture information acquisition step, When it is determined that the current posture of the vehicle body is a predetermined reference posture and matches the posture of the vehicle when it is stationary on a level road surface, a predetermined standard value is assigned to the torque threshold. If it is determined that the current posture of the vehicle body is different from the reference posture, a predetermined value greater than the standard value is assigned to the torque threshold. When pitching is detected in the vehicle body, a predetermined first torque value is assigned as the predetermined value, and when rolling is detected in the vehicle body, at least one of the following assignments is performed: A hands-on determination method for a steering wheel, configured to include a threshold setting step.

3. The computer installed in the vehicle, A torque detection step that detects the torque applied to the steering wheel, A determination step in which, if the torque exceeds a torque threshold, it is determined that the driver is in a hands-on state, gripping the steering wheel; This is a hands-on judgment program to execute, The determination step includes an attitude information acquisition step that acquires information regarding the attitude of the vehicle body, The aforementioned determination step is performed based on the information obtained in the posture information acquisition step, When it is determined that the current posture of the vehicle body is a predetermined reference posture and matches the posture of the vehicle when it is stationary on a level road surface, a predetermined standard value is assigned to the torque threshold. If it is determined that the current posture of the vehicle body is different from the reference posture, a predetermined value greater than the standard value is assigned to the torque threshold. When pitching is detected in the vehicle body, a predetermined first torque value is assigned as the predetermined value, and when rolling is detected in the vehicle body, at least one of the following assignments is performed: A hands-on determination program for a steering wheel, configured to include a threshold setting step.

Images