VEHICLE BODY POSITION DETECTION DEVICE AND SADDLE-TYPE VEHICLE

Abstract

Vehicle body position detection device, which sequentially estimates a roll angle of a vehicle body of a semi-trailer type vehicle, which has an x-axis extending in a longitudinal direction of the vehicle body, a y-axis extending in a width direction of the vehicle body, and a z-axis extending in a vertical direction of the vehicle body, as a coordinate system fixed to the vehicle body, wherein the vehicle body position detection device comprises: a speed sensor which detects the speed of the vehicle body in a direction of travel; a detection unit comprising a plurality of acceleration sensors corresponding to axes, which detect translational acceleration in directions of the x-axis, the y-axis and the z-axis, and a plurality of angular velocity sensors corresponding to axes, which detect angular velocity in a direction about the x-axis and angular velocity in a direction about the z-axis; a pitch angle estimator that sequentially estimates the pitch angle of the vehicle body; a roll angular velocity estimator that sequentially estimates the roll angular velocity of the vehicle body; a state determination device which determines a driving state of the semi-trailer-type vehicle by comparing a parameter calculated on the basis of a detection value detected by the detection unit with a threshold value; a correction value calculation tool which sequentially calculates a correction value for estimating a roll angle of the vehicle body based on a variable correction coefficient determined according to the determination of the state determination tool and detection values ​​from the speed sensor and the detection unit; and a roll angle estimation calculator which calculates an estimate of a current roll angle of the vehicle body by integrating a value obtained by correcting the estimate of the roll angle velocity on the basis of the correction value, characterized in that The correction value calculation method sets the variable correction coefficient in such a way that the correction value decreases when the parameter exceeds the threshold.

Description

TECHNICAL AREA

[0001] The present invention relates to a vehicle body position detection device and a semi-trailer-type vehicle which estimate a roll angle of a vehicle body. BACKGROUND STATE OF THE ART

[0002] It is often necessary to estimate the roll angle (angle of inclination in the direction of roll) of a vehicle body, such as a motorcycle, in real time. For example, patent literature 1 proposes a method for estimating the roll angle (angle of lateral tilt in the description of patent literature 1) of a vehicle body in order to control a beam pattern of a motorcycle headlight. QUOTE LIST PATENT LITERATURE

[0003] PTL1: Japanese patent, publication no. JP 2010-149681A

[0004] Furthermore, US 2010 / 0 168 958 A1 discloses a lean angle detection device comprising a roll rate sensor for detecting an angular velocity about a longitudinal axis of the motorcycle, a yaw rate sensor for detecting an angular velocity about a vertical axis of the motorcycle; a lean angle detection unit for detecting the motorcycle lean angle for calibration use based on the yaw rate and a vehicle speed; and a lean angle correction unit for correcting the basic motorcycle lean angle determined from an output of the yaw rate sensor in order to approximate the motorcycle lean angle detected by the lean angle detection unit in order to determine the estimated lean angle.

[0005] Furthermore, DE 10 2018 202 664 A1 discloses a control unit for a single-track vehicle. The control unit is configured to acquire sensor data relating to the vehicle's yaw rate and longitudinal speed. The control unit is also configured to determine a measured value for the vehicle's roll angle based on the sensor data. Finally, the control unit is configured to update an estimated value of the roll angle based on the measured value and a state model of the vehicle.

[0006] Furthermore, DE 10 2006 061 483 B4 discloses a method for determining the roll angle of a motorcycle, wherein a rolling rate of the vehicle is determined, in particular by means of a yaw rate sensor, a first roll angle parameter is determined from the roll rate, at least one further vehicle dynamic parameter, in particular a speed and / or a yaw rate and / or an acceleration, of the vehicle is determined, at least a second roll angle parameter is determined on the basis of this vehicle dynamic parameter(s), and the roll angle is calculated from the roll angle parameters, in particular by addition, as well as a device for determining the roll angle of a motorcycle, which comprises at least one evaluation unit, a means for determining a roll rate of the vehicle, and at least one means for determining at least one further vehicle dynamic parameter.where the further vehicle dynamics parameter is in particular a vehicle speed and / or a yaw rate of the vehicle and / or an acceleration of the vehicle.

[0007] Furthermore, DE 10 2012 016 108 A1 discloses a method for determining the speed of a single-track vehicle, in particular a two-wheeler, which has a front wheel having a front wheel pivot axis and a rear wheel having a rear wheel pivot axis, comprising the steps (a) determining the rotational speed of at least one wheel of the vehicle, and (b) calculating the speed based on the rotational speed of a circumferential parameter of the wheel, as well as a single-track vehicle with a front wheel having a front wheel pivot axis, a rear wheel having a rear wheel pivot axis, at least one rotational speed sensor for determining the rotational speed of at least one wheel of the vehicle, and an electrical evaluation unit.which is set up to automatically carry out a procedure comprising the steps (a) detecting the rotational speed of at least one wheel and (b) calculating the driving speed based on the rotational speed and a circumferential parameter of the wheel.

[0008] Finally, DE 10 2016 220 559 A1 discloses a method and a system for determining the roll angle of a two-wheeler during cornering. The method comprises the steps of recording a sequence of images of the two-wheeler's surroundings using a camera mounted on the two-wheeler, extracting an optical flow from the image sequence, determining the roll angle of the camera based on the extracted optical flow, and determining the roll angle of the two-wheeler based on the determined roll angle of the camera. SUMMARY OF THE INVENTIONAL PROBLEM

[0009] In the method proposed in patent literature 1, an estimated value of the roll angle is calculated using, as a convergence target value, a roll angle value in a steady state in which a moment in the rolling direction due to centrifugal force and a moment in the rolling direction due to gravity are balanced.

[0010] However, in the calculation of the estimated value described in patent literature 1, a physical relationship established in the steady state, such as the relationship of an acceleration acting in a lateral direction of the vehicle, is not established in a non-stationary state (transition state), such as a drifting driving state or a jump state of the vehicle. Therefore, if the calculation of the roll angle estimate is based on a correction value that includes an estimated value in a transition state, a case may arise in which error components accumulate and the error of the roll angle estimate can simply increase.

[0011] An object of the present invention is to provide a vehicle body position detection device which is capable of calculating a correction value using a variable correction coefficient determined according to a driving condition of a vehicle and of estimating a roll angle on the basis of the calculated correction value. SOLUTION TO THE PROBLEM

[0012] A vehicle body position detection device according to one aspect of the present invention is a vehicle body position detection device which sequentially estimates a roll angle of a vehicle body of a semi-trailer-type vehicle, which has an x-axis extending in a longitudinal direction of the vehicle body, a y-axis extending in a width direction of the vehicle body, and a z-axis extending in a vertical direction of the vehicle body, as a coordinate system fixed to the vehicle body, wherein the vehicle body position detection device comprises: a speed sensor which detects the speed of the vehicle body in a direction of travel; a detection unit comprising a plurality of acceleration sensors corresponding to axes, which detect translational acceleration in directions of the x-axis, the y-axis and the z-axis, and a plurality of angular velocity sensors corresponding to axes, which detect angular velocity in a direction about the x-axis and angular velocity in a direction about the z-axis; a pitch angle estimator that sequentially estimates the pitch angle of the vehicle body; a roll angular velocity estimator that sequentially estimates the roll angular velocity of the vehicle body; a state determination device which determines a driving state of the semi-trailer-type vehicle by comparing a parameter calculated on the basis of a detection value detected by the detection unit with a threshold value; a correction value calculation tool which sequentially calculates a correction value for estimating a roll angle of the vehicle body based on a variable correction coefficient determined according to the determination of the state determination tool and detection values ​​from the speed sensor and the detection unit; and a roll angle estimation calculator which calculates an estimate of a current roll angle of the vehicle body by integrating a value obtained by correcting the estimate of the roll angle velocity on the basis of the correction value, characterized in that The correction value calculation method sets the variable correction coefficient in such a way that the correction value decreases when the parameter exceeds the threshold. ADVANTAGEOUS EFFECTS OF THE INVENTION

[0013] According to the present invention, it is possible to calculate a correction value using a variable correction coefficient determined according to a driving condition of a vehicle and to estimate a roll angle based on the calculated correction value. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a perspective view showing part of a motorcycle on which a vehicle body position detection device according to one embodiment is mounted. Fig. Figure 2 is a representation that depicts a functional configuration of the vehicle body position detection device according to the embodiment. Fig. Figure 3 is a block diagram for describing the processing content of the vehicle body position detection device. Fig. Figure 4 is a representation showing the forces acting on a motorcycle while cornering. Fig. Figure 5 is a representation to explain the process of determining a variable correction coefficient K3. Fig. Figure 6 is a representation that depicts a table of a memory. DESCRIPTION OF EXECUTION FORMS

[0014] One embodiment is described in detail below with reference to the accompanying drawings. It should be noted that the following embodiment does not limit the invention according to the claims and that not all combinations of features described in the embodiment are essential to the invention.

[0015] Fig. Figure 1 is a perspective view showing part of a motorcycle on which a vehicle body position detection device according to one embodiment is mounted. As in Fig. Figure 1 shows a vehicle body position detection device 1 of the present embodiment as a device which estimates the roll angle of a vehicle body 101 of a motorcycle 100 (vehicle of the saddle type) mounted on the motorcycle 100.

[0016] Here, a local coordinate system and a global coordinate system are described, which are used in Fig. 1 are shown and which are assumed in the following description of the present embodiment.

[0017] The local coordinate system is a coordinate system that is fixed with respect to the vehicle body 101 (a coordinate system that moves integrally with the vehicle body 101). As in Fig. As shown in Figure 1, the local coordinate system is defined as an orthogonal xyz coordinate system in which an axis extending in the longitudinal direction of the vehicle body 101 is an x-axis (first axis), an axis extending in the width direction of the vehicle body 101 is a y-axis (second axis), and an axis extending in the vertical direction of the vehicle body 101 is a z-axis (third axis).

[0018] Additionally, the global coordinate system is an inertial coordinate system for expressing the state of motion of the vehicle body 101 as seen from the driving environment of the motorcycle 100 (motion environment of the vehicle body 101). The global coordinate system is defined as an orthogonal XYZ coordinate system in which a horizontal axis in the same direction as an axis obtained by projecting the x-axis of the local coordinate system onto a horizontal plane is an X-axis, a horizontal axis in the same direction as an axis obtained by projecting the y-axis of the local coordinate system onto a horizontal plane is a Y-axis, and an axis in the vertical direction (direction of gravity) is a Z-axis.

[0019] In this case, when the motorcycle 100 is stationary in a straight-line riding position on a horizontal plane, the x-axis, y-axis, and z-axis directions of the local coordinate system coincide with the x-axis, y-axis, and z-axis directions of the global coordinate system, respectively. The global coordinate system is a coordinate system that moves with the movement of the vehicle body 101 and is not a coordinate system that is always fixed to the road surface.

[0020] Additionally, the roll angle, pitch angle and yaw angle of the vehicle body 101 are expressed as an angle about the X-axis, an angle about the Y-axis and an angle about the Z-axis of the global coordinate system, respectively. In the present embodiment, the roll angle, pitch angle, and yaw angle of the vehicle body 101 are angles expressed in Euler angles. Based on the above, the vehicle body position detection device 1 is described in detail.

[0021] (Functional configuration of the vehicle body position detection device) Fig. Figure 2 is a representation depicting a functional configuration of the vehicle body position detection device 1 according to the embodiment. As shown in Fig. As shown in Figure 2, the vehicle body position detection device 1 comprises a vehicle speed sensor 2, which detects a vehicle speed V as a direction of travel of the vehicle body 101, an inertial sensor unit 3, which detects an acceleration and an angular velocity generated in the vehicle body 101, and an estimation processing unit 6, which estimates the roll angle, for example, on the basis of detection signals input from the vehicle speed sensor 2 and the inertial sensor unit 3.

[0022] The vehicle speed sensor 2 includes, for example, a rotational speed sensor, such as a rotary encoder, which outputs a detection signal corresponding to the rotational speed of a rear wheel of the motorcycle 100. In this case, the wheel speed of the rear wheel, which corresponds to the detection value of the rotational speed of the rear wheel, is obtained as the detection value of the vehicle speed.

[0023] It should be noted that the vehicle speed sensor 2 can detect the rotational speeds of both the front and rear wheels and calculate the vehicle speed based on these detected values. The vehicle speed sensor 2 can be a sensor of a different type (e.g., a vehicle speed sensor using GPS, etc.), as long as the sensor can detect the directional speed of the vehicle body 101.

[0024] The inertial measurement unit 3 (IMU) is a sensor unit capable of detecting the behavior of the motorcycle 100 by detecting the acceleration and angular velocity generated in the vehicle body 101. As in Fig. As shown in Figure 2, the inertial sensor unit 3 can be arranged at any suitable position on the vehicle body 101, such as near the center of gravity of the motorcycle 100. The inertial sensor unit 3 comprises, as sensors that detect translational acceleration, an x-axis accelerometer 4x, which detects translational acceleration (hereinafter referred to as x-axis acceleration) in the x-axis direction (longitudinal direction of the motorcycle 100) of the local coordinate system, a y-axis accelerometer 4y, which detects translational acceleration (hereinafter referred to as y-axis acceleration) in the y-axis direction (lateral direction of the motorcycle 100), and a y-axis accelerometer 4z, which detects translational acceleration (hereinafter referred to as z-axis acceleration) in the z-axis direction (vertical direction of the motorcycle 100).

[0025] Additionally, the inertial sensor unit 3 includes, as sensors which detect an angular velocity, an x-axis angular velocity sensor 5x, which detects an angular velocity (hereinafter referred to as x-axis angular velocity) about the x-axis, a y-axis angular velocity sensor 5y, which detects an angular velocity (hereinafter referred to as y-axis angular velocity) about the y-axis, and a z-axis angular velocity sensor 5z, which detects an angular velocity (hereinafter referred to as z-axis angular velocity) about the z-axis.

[0026] The estimation processing unit 6 comprises a processor 61, which includes a processor such as a CPU, a memory 62, which includes components such as a RAM 62b, which stores a result (previous value) of a sequential arithmetic processing operation, and a ROM 62a, which contains a table 600 ( Fig. 6) stores, which will be described later, and an electronic control unit (ECU) comprising an interface unit 63 (I / F unit) that transmits and receives signals between an external device comprising the vehicle speed sensor 2 and the inertial sensor unit 3, and the processor 61. The estimation processing unit 6 is mounted at any suitable position on the motorcycle 100. It should be noted that the estimation processing unit 6 can comprise a plurality of electronic control units that can communicate with each other.

[0027] The estimation processing unit 6 comprises a roll angle velocity estimator 11, a correction value calculation device 12, a pitch angle estimator 13 and a roll angle estimation value calculation device 14 as functions which are implemented by a program built into memory 62, or function configurations which are implemented by a hardware configuration.

[0028] Fig. Figure 3 is a block diagram describing the contents of a processing operation for each function configuration in the estimation processing unit 6. Fig. 3 indicates “S” differential operation and “1 / S” indicates integral operation. (Roll angle velocity estimation device 11)

[0029] ST31 in Fig. Figure 3 is a block diagram depicting the processing content of the roll angular velocity estimator 11. An x-axis angular velocity (ωx), a z-axis angular velocity (ωz), cosφ, and tanθ are input into the roll angular velocity estimator 11. The roll angular velocity estimator 11 estimates a roll angular velocity φdot (rate of change of the roll angle φ) of the vehicle body 101 based on the input signal. Here, the x-axis angular velocity (ωx) and the z-axis angular velocity (ωz) are based on detection signals detected by the x-axis angular velocity sensor 5x and the z-axis angular velocity sensor 5z of the inertial sensor unit 3.

[0030] Additionally, cosφ is a cosine function value based on the previous roll angle (φ) estimated in the previous calculation processing cycle by the arithmetic processing of the roll angle estimation unit 14. Additionally, tanθ is a tangent function value based on the previous pitch angle (θ) estimated in the previous arithmetic processing cycle by the arithmetic processing of the pitch angle estimation unit 13.

[0031] If a processing in the roll angular velocity estimation device 11 is expressed by a formula, the roll angular velocity φdot (= dφ / dt) can be approximated by the following equation (1). φdot≈ωx+cosφ⋅tanθ⋅ωz

[0032] The roll angular velocity estimator 11 calculates an estimate of the roll angular velocity φdot using equation (1) as a basic equation. In each arithmetic processing cycle, the roll angular velocity estimator 11 acquires a detection value (present value) of the x-axis angular velocity ωx and a detection value (present value) of the z-axis angular velocity ωz based on the detection signal from the inertial sensor unit 3. Additionally, the roll angular velocity estimator 11 acquires an estimate (previous value φ) of the roll angle φ and an estimate (previous value θ) of the pitch angle θ, which were calculated in the previous arithmetic processing cycle by the roll angle estimator 14 and the pitch angle estimator 13, respectively.

[0033] Then the roll angular velocity estimator 11 calculates an estimate of the roll angular velocity φ by calculating the right-hand side of equation (1) using the detection value (present value) of the z-axis angular velocity ωz, the detection value (present value) of the z-axis angular velocity ωz, the estimate (previous value φ) of the roll angle φ and the estimate (previous value θ) of the pitch angle θ. (Pitch angle estimation device 13)

[0034] ST33 in Fig. Figure 3 is a block diagram depicting the processing content of the pitch angle estimator 13. The vehicle speed V, cosθ, and an x-axis acceleration (ax) are input into the pitch angle estimator 13. The pitch angle estimator 13 estimates the pitch angle θ of the vehicle body 101 based on the input signal.

[0035] Here, the vehicle speed V is based on the calculation of the front wheel speed and the detection signal, which corresponds to the rotational speed of the rear wheel of motorcycle 100 output by the vehicle speed sensor 2. Additionally, cosθ is a cosine function value based on the previous pitch angle (θ) estimated in the previous arithmetic processing cycle by the pitch angle estimation device 13. Furthermore, the x-axis acceleration (ax) is based on a detection signal detected by the x-axis acceleration sensor 4x of the inertial sensor unit 3.

[0036] If a processing in the roll angular velocity estimation device 11 is expressed by a formula, the roll angular velocity φdot can be approximated by the following equation (2). θ=sin−1(Vdot⋅cosθ−ax)

[0037] In equation (2), Vdot, viewed in the global coordinate system, is a rate of change over time (= dV / dt: acceleration in the x-axis direction) of the vehicle velocity V in the x-axis direction of the vehicle body 101. The pitch angle estimator 13 calculates an estimate of the pitch angle θ using equation (2) as a basic equation.In each arithmetic processing cycle, the pitch angle estimator 13 acquires a rate of change over time (rate of change between a present value and a previous value) of the vehicle speed V based on the detection signal of the vehicle speed sensor 2, an estimated value (previous value) of the pitch angle θ calculated by the pitch angle estimator 13 in the previous arithmetic processing cycle, and a detection value (present value) of the x-axis acceleration ax based on the detection signal of the x-axis acceleration sensor 4x of the inertial sensor unit 3.

[0038] Then the pitch angle estimator 13 calculates an estimate of the pitch angle θ by calculating the right side of equation (2) using the rate of change over time (rate of change over time between a present value and a previous value) of the vehicle speed V, the estimated value (previous value) of the pitch angle θ and the detection value (present value) of the x-axis acceleration ax. (Correction value calculation device 12)

[0039] ST32 in Fig. Figure 3 is a block diagram depicting the processing content of the correction value calculation unit 12. The correction value calculation unit 12 calculates a correction value δ to reduce an error in the estimated roll angle φ of the vehicle body 101. In principle, the roll angle φ of the vehicle body 101 can be estimated by integrating the estimated roll speed φdot calculated by the roll angular velocity estimation unit 11. However, if the calculation of the roll angle estimate is performed in a transition state, error components can accumulate, and the error of the roll angle estimate can simply increase.For this reason, when outputting the calculated correction value δ, the correction value calculation device 12 determines whether the driving state of the motorcycle 100 is a stationary state or a non-stationary state (transition state), such as a drift state or a jump state, and changes the setting of an output gain K3 of the correction value according to the determination result.

[0040] The correction value calculation device 12 sequentially calculates a correction value to estimate the roll angle of the vehicle body using the variable correction coefficient K3, determined according to the absolute value (rate of change over time) of the difference value of the angular velocity detected by the inertial sensor unit 3 in the direction about the z-axis, the detection value of the velocity by the speed sensor, each of the detection values ​​of the z-axis angular velocity and the y-axis acceleration, the previous estimate of the roll angle and the previous estimate of the pitch angle.

[0041] The z-axis angular velocity (ωz), the y-axis acceleration (ay_lyout: hereinafter referred to as ay), cosθ, sinφ, and the vehicle speed V are input into the correction value calculation unit 12. Here, the z-axis angular velocity (ωz) is based on the detection signal detected by the z-axis angular velocity sensor 5z of the inertial sensor unit 3. The y-axis angular velocity (ay) is based on a detection signal detected by the y-axis acceleration sensor 4z of the inertial sensor unit 3. Here, cosθ is a cosine function value based on the previous pitch angle (θ) estimated in the previous arithmetic processing cycle by the arithmetic processing of the pitch angle estimation unit 13.Additionally, sinφ is a sine function value based on the previous roll angle (φ) estimated in the previous arithmetic processing cycle by the arithmetic processing of the roll angle estimation calculation device 14. Furthermore, the vehicle speed V is based on the calculation of the front wheel speed and the detection signal, which corresponds to the rotational speed of the rear wheel of the motorcycle 100 output by the vehicle speed sensor 2.

[0042] Fig. Figure 4 is a representation depicting the forces acting on the motorcycle 100 during a uniform cornering maneuver. In the block diagram from ST32, Ay, viewed in the global coordinate system, is the acceleration in the Y-axis direction of the vehicle body 101 and is a parameter corresponding to the acceleration in the Y-axis direction due to the centrifugal force, which is expressed by the following equation (3). Ay=ωz⋅V In the block diagram from ST32, ay_estm is an estimated value of the y-axis acceleration, and the estimated value ay_estm of the y-axis acceleration during uniform cornering can be calculated by the following equation (4) using the detection value (current value) of the z-axis angular velocity ωz based on the detection signal of the inertial sensor unit 3, the estimated value (previous value) of the pitch angle θ estimated in the previous arithmetic processing cycle, and the estimated value (previous value) of the roll angle φ. In equation (4), g represents the acceleration due to gravity. ay_estm=ωz⋅V+cosθ⋅sinφ⋅g In the block diagram from ST32, the value of the y-axis acceleration ay is detected by the y-axis acceleration sensor 4z of the inertial sensor unit 3 and, if the error of the estimated value of the roll angle φ is not included in the estimated value ay_estm of the y-axis acceleration calculated by equation (4), the relationship of the following equation (5) is established. ay≈ωz⋅V+cosθ⋅sinφ⋅g In equation (5) a deviation err (ay-ay_estm) between ay and ay_estm corresponds to the error of the estimated value of the roll angle φ in a steady state.

[0043] The correction value calculation unit 12 calculates a bias deviation (K3-err) obtained by multiplying the deviation err (= ay-ay_estm) by the variable correction coefficient value K3. Here, the variable correction coefficient K3 is a coefficient value that is variably determined according to the driving state of the motorcycle 100. The correction value calculation unit 12 functions as a state determination unit, which determines the driving state of the vehicle of the saddle-type by comparing a parameter calculated on the basis of the inertial sensor unit 3 (detection unit) (e.g., an absolute value of the difference value of the z-axis angular velocity (ωz), a sum of detection values ​​from a plurality of accelerometers, and the like) with a threshold value.The correction value calculation device 12 sequentially calculates a correction value for estimating the roll angle of the vehicle body based on the variable correction coefficient determined according to the result of the determination and the detection values ​​of the speed sensor and the inertial sensor unit 3 (detection unit). That is, the correction value calculation device 12 sequentially calculates the correction value δ for estimating the roll angle of the vehicle body based on the following equation (6) using the bias deviation multiplied by the variable correction coefficient K3 determined according to the result of the determination.

[0044] The correction value calculation device 12 calculates the correction value δ such that the deviation err (= ay-ay_estm) in the steady state approaches zero based on equation (6). In equation (6), K1 and K2 are predetermined fixed correction coefficient values. Predetermined constant values ​​are set for the fixed correction coefficients K1 and K2, independent of the driving state of the motorcycle 100. δ=K3⋅{K1⋅(ay−ay_estm)+K2⋅∫(ay−ay_estm)dt}

[0045] In equation (6), the term of the fixed correction coefficient K2 corrects an offset component included in the estimated value of the roll angle (φ) in a normal driving condition (steady state), which is a deviation from the zero point.

[0046] The variable correction coefficient K3 is a coefficient whose value can be variably set based on a parameter specifying the riding condition of the motorcycle 100. The parameter specifying the riding condition includes, for example, an absolute value of a difference value of the z-axis angular velocity (ωz), and the correction value calculation device 12 can set the variable correction coefficient K3 according to the absolute value (rate of change over time) of the difference value of the z-axis angular velocity (ωz).

[0047] Fig. Figure 5 is a representation to explain the sequence of a procedure for determining the variable correction coefficient K3. First, in step S51, the correction value calculation device 12 acquires a detection value (previous value) of the z-axis angular velocity ωz and the detection value (current value) of the z-axis angular velocity ωz based on the detection signal of the inertial sensor unit 3 in each arithmetic processing cycle.

[0048] Then, in step S52, the correction value calculation device 12 calculates the absolute value (rate of change over time) of the difference value of the z-axis angular velocity ωz in one arithmetic processing cycle (ΔT) based on the difference between the detection value (previous value) of the z-axis angular velocity ωz and the detection value (current value) of the z-axis angular velocity ωz.

[0049] In step S53, the correction value calculation unit 12 compares the calculated absolute value (rate of change over time) of the difference value of the z-axis angular velocity ωz with a predefined first state determination threshold (first threshold). Here, the first state determination threshold (first threshold) is a threshold used to determine whether the driving state of the motorcycle 100 is a non-stationary state (transition state), such as a drift state, or not. The correction value calculation unit 12 determines that the driving state of the motorcycle 100 is a transition state, such as a drift state, if the absolute value (rate of change over time) of the difference value of the z-axis angular velocity ωz exceeds the first state determination threshold.It should be noted that the first state determination threshold (first threshold) is stored in advance in memory 62, and the correction value calculation device 12 can retrieve the first state determination threshold (first threshold) from memory 62 at the time of an arithmetic processing.

[0050] During the determination in step S53, if the absolute value (rate of change over time) of the difference value of the z-axis angular velocity ωz exceeds the first state determination threshold (Yes in S53), the correction value calculation device 12 sets the variable correction coefficient K3 to zero (K3 = 0).

[0051] If the parameter (absolute value of a difference value of a z-axis angular velocity ωz) exceeds the threshold, the correction value calculation device 12 sets the variable correction coefficient K3 such that the correction value decreases. That is, if the absolute value (rate of change over time) of the difference value of the z-axis angular velocity ωz exceeds the first state determination threshold and the driving state of the motorcycle 100 is determined to be the transition state, the correction value calculation device 12 sets the value of the variable correction coefficient K3 to zero to cancel the correction effect.

[0052] On the other hand, if the absolute value (rate of change over time) of the difference value of the z-axis angular velocity ωz when determined from step S53 is equal to or less than the first state determination threshold (No in S53), the correction value calculation device 12 proceeds with processing to step S55.

[0053] Then, in step S55, the correction value calculation unit 12 can set the variable correction coefficient K3 according to the rate of change over time. The correction value calculation unit 12 sets the variable correction coefficient K3 such that the correction value δ decreases in accordance with an increase in the absolute value (rate of change over time) of the difference value of the z-axis angular velocity ωz.

[0054] If the variable correction coefficient K3 is fixed, a table 600, in which the absolute value of the difference value of the z-axis angular velocity ωz and the corresponding variable correction coefficient K3 are pre-assigned, can be stored in memory 62 (ROM 62a). In this case, the correction value calculation device 12 can consult the table in memory 62, retrieve the variable correction coefficient K3 from table 600 corresponding to the absolute value (rate of change over time) of the difference value of the calculated z-axis angular velocity ωz, insert the variable correction coefficient K3 into equation (6), and output the correction value δ multiplied by the variable correction coefficient K3 retrieved from the table.

[0055] Fig. Figure 6 is a representation depicting Table 600 of Memory 62 (ROM 62a). As in Fig. As shown in Figure 6, a plurality of values ​​(ωz_dot_1, ωz_dot_2, ωz_dot_3, ..., ωz_dot_6) are defined as absolute values ​​of the difference values ​​of the z-axis angular velocity ωz (yaw rate). The absolute value of the difference value is defined such that the value of ωz_dot_1 is small and increases to ωz_dot_2, ωz_dot_3, ωz_dot_4, ωz_dot_5 ..., and exceeds the first threshold value (first state determination threshold) at ωz_dot_6.

[0056] Additionally, Table 600 assigns a plurality of values ​​(K3_1, K3_2, K3_3, etc.) to the absolute values ​​of the difference values ​​of the z-axis angular velocity ωz (yaw rate) as the variable correction coefficient K3. In Table 600, the value of the variable correction coefficient K3 is defined such that its value decreases in accordance with an increase in the absolute value (rate of change over time) of the difference value of the z-axis angular velocity ωz (yaw rate). That is, the defined values ​​decrease in the order K3_1 → K3_2 → K3_3 → K3_4 → K3_5, and zero is defined for the absolute value of the difference value of the z-axis angular velocity ωz (yaw rate) that exceeds the first state determination threshold (K3_6 = 0).By setting the variable correction coefficient K3 to zero, the calculation result of equation (6) for calculating the correction value δ becomes zero and the output of the correction value δ for calculating an estimate of the roll angle φ can be omitted.

[0057] It should be noted that the setting example in Table 600 is exemplary and not limited to this example. Furthermore, the parameter specifying the driving state of motorcycle 100 is not limited to the absolute value of the difference value of the z-axis angular velocity (ωz), and it is also possible, for example, to determine it based on the sum of acceleration detection values ​​of the majority of acceleration sensors (4x, 4y, 4z) included in the inertial sensor unit 3. Fig. 2) to determine whether the driving state of the motorcycle 100 is in a transitional state, such as a jump state or not.

[0058] In this case, the correction value calculation unit 12 compares the sum of the acceleration detection values ​​of the majority of acceleration sensors detected by the inertial sensor unit 3 (detection unit) as a parameter with a predefined second state determination threshold (second threshold). Here, the second state determination threshold (second threshold) is a threshold for determining whether the driving state of the motorcycle 100 is in a non-stationary state (transition state), such as a jump state, or not.The correction value calculation device 12 determines that the driving state of the motorcycle 100 is the transition state (non-stationary state), such as a jump state, when the sum of the acceleration detection values ​​of the majority of acceleration sensors exceeds the second state determination threshold (second threshold), and the correction value calculation device 12 sets the variable correction coefficient K3 to zero (K3 = 0). By setting the variable correction coefficient K3 to zero, the calculation result of equation (6) for calculating the correction value δ becomes zero, and the output of the correction value δ for calculating an estimate of the roll angle φ can be omitted.The second state determination threshold (second threshold) is stored in advance in memory 62 and the correction value calculation device 12 can retrieve the second state determination threshold (second threshold) from memory 62 at the time of an arithmetic processing.

[0059] On the other hand, if the sum of the acceleration detection values ​​of the majority of acceleration sensors is equal to or less than the second state determination threshold (second threshold), the correction value calculation device 12 determines that the driving state of the motorcycle 100 is a steady state and sets 1 as the value of the variable correction coefficient K3. In this case, the correction value calculation device 12 calculates the correction value δ based on equation (6) and inputs the calculation result into the roll angle estimation calculation device 14. (Roll angle estimation calculation device 14)

[0060] ST34 in Fig. Figure 3 is a block diagram depicting the processing content of the roll angle estimation unit 14. The estimated roll angle velocity φdot and the correction value δ are entered into the roll angle estimation unit 14. The roll angle estimation unit 14 calculates an estimated roll angle φ based on the estimated roll angle velocity φdot from the roll angle velocity estimation unit 11 and the calculated correction value δ from the correction value calculation unit 12.In each arithmetic processing cycle, the roll angle estimation unit 14 integrates a value (= φdot-δ) obtained by correcting the estimate (present value) of the roll angle velocity φdot calculated by the roll angle velocity estimation unit 11 on the basis of the correction value δ (present value) calculated by the correction value unit 12, thereby calculating a corrected estimate of the roll angle φ. <Zusammenfassung der Erfindung>

[0061] The above embodiment discloses at least the following configurations.

[0062] Configuration 1. A vehicle body position detection device according to the above embodiment is a vehicle body position detection device (e.g. 1 from Fig. 2), which sequentially determines a roll angle of a vehicle body (101 from Fig. 1) a vehicle of the articulated type (e.g. 100 from Fig. 1) estimates which has an x-axis extending in a longitudinal direction of the vehicle body, a y-axis extending in a width direction of the vehicle body, and a z-axis extending in a vertical direction of the vehicle body as a coordinate system fixed to the vehicle body, wherein the vehicle body position detection device comprises: a speed sensor (e.g. 2 from Fig. 2), which detects the speed of the vehicle body in a direction of travel; a detection unit (e.g. 3 from Fig. 2), which includes a plurality of acceleration sensors (e.g. 4x, 4y, 4z from Fig. 2) corresponding axes that detect translational acceleration in directions of the x-axis, the y-axis and the z-axis, and a plurality of angular velocity sensors (e.g. 5x, 5z from Fig. 2) includes axes that detect an angular velocity in one direction around the x-axis and an angular velocity in one direction around the z-axis; a pitch angle estimator (e.g. 13 from Fig. 2), which sequentially estimates a pitch angle of the vehicle body; a roll angle velocity estimator (e.g. 11 from Fig. 2), which sequentially estimates a roll angle velocity of the vehicle body; a means of determining state (e.g. 12 from Fig. 2), which determines a driving state of the semi-trailer-type vehicle by comparing a parameter calculated on the basis of a detection value detected by the detection unit with a threshold value; a correction value calculation tool (e.g. 12 from Fig. 2) which sequentially calculates a correction value for estimating a roll angle of the vehicle body based on a variable correction coefficient determined according to the determination of the state determination means and detection values ​​from the speed sensor and the detection unit; and a roll angle estimation tool (e.g. 14 from Fig. 2), which calculates an estimated value of a current roll angle of the vehicle body by integrating a value obtained by correcting the estimated value of the roll angular velocity on the basis of the correction value, wherein the correction value calculation means (12) sets the variable correction coefficient (K3) such that the correction value decreases when the parameter exceeds the threshold.

[0063] According to the vehicle body position detection device according to configuration 1, it is possible to calculate the correction value using the variable correction coefficient determined according to the driving condition of the vehicle and to estimate the roll angle based on the calculated correction value.

[0064] Configuration 2. In the vehicle body position detection device according to the embodiment, the correction value calculation means (12) calculates the correction value using the variable correction coefficient, a detection value of the speed by the speed sensor, each of the detection values ​​of the z-axis angular velocity and the y-axis acceleration by the detection unit, a previous estimate of the roll angle and a previous estimate of the pitch angle.

[0065] Configuration 3. In the vehicle body position detection device according to the embodiment, the correction value calculation means (12) calculates a rate of change over time of the angular velocity detected by the detection unit in the direction about the z-axis as the parameter, detects a first threshold value as the threshold value and determines the variable correction coefficient (K3) on the basis of a comparison between the rate of change over time and the first threshold value.

[0066] According to the vehicle body position detection devices according to configurations 2 and 3, it is possible to calculate the correction value using the variable correction coefficient determined according to the driving condition of the vehicle.

[0067] Configuration 4. In the vehicle body position detection device according to the embodiment, the correction value calculation means (12) sets the value of the variable correction coefficient to zero in order to set the correction value to zero when the rate of change over time exceeds the first threshold.

[0068] According to the vehicle body attitude detection device in configuration 4, if the rate of change over time exceeds the first threshold, the driving condition is considered a transitional state, such as a drift state, and the value of the variable correction coefficient is set to K3 = 0, so that the correction value becomes zero, thus eliminating the output of the correction value in the transitional state. As a result, the error in the roll angle estimate during sequential operation can be reduced, and the estimation accuracy can be further improved.

[0069] Configuration 5. The vehicle body position detection device according to the embodiment further comprises a storage means (e.g. 62, 62a from Fig. 2), which stores a rate of change of the angular velocity in the direction about the z-axis and a value of the variable correction coefficient, and, if the calculated rate of change is equal to or less than a threshold value, the correction value calculation means (12) retrieves the variable correction coefficient according to the rate of change from the storage means (62, 62a) and outputs a correction value multiplied by the variable correction coefficient retrieved from the storage means (62, 62a).

[0070] Configuration 6. In the vehicle body position detection device according to the embodiment, the storage means (62, 62a) stores the variable correction coefficient, which is set such that its value decreases in accordance with an increase in the rate of change over time.

[0071] According to the vehicle body position detection devices according to configurations 5 and 6, by setting the variable correction coefficient according to the rate of change over time with reference to the storage medium, it is possible to reduce the error of the estimated value of the roll angle in sequential operation and to further improve the estimation accuracy, while speeding up the processing through sequential operation.

[0072] Configuration 7. In the vehicle body position detection device according to the embodiment, the correction value calculation means (12) calculates a sum of detection values ​​of the plurality of acceleration sensors (4x, 4y, 4z) detected by the detection unit as the parameter, records a second threshold as the threshold value and determines the variable correction coefficient on the basis of a comparison between the sum and the second threshold value.

[0073] According to the vehicle body position detection device according to configuration 7, it is possible to calculate the correction value using the correction coefficient determined according to the driving condition of the vehicle.

[0074] Configuration 8. In the vehicle body position detection device according to the embodiment, the correction value calculation means (12) sets the value of the variable correction coefficient to zero in order to set the correction value to zero when the sum exceeds the second threshold.

[0075] According to the vehicle body position detection device in configuration 8, if the sum exceeds the second threshold, the driving condition is considered a transitional state, such as a jump state, and the value of the variable correction coefficient is set to K3 = 0, so that the correction value becomes zero, thus eliminating the correction value in the transitional state. As a result, the error in the roll angle estimate during sequential operation can be reduced, and the estimation accuracy can be further improved.

[0076] Configuration 9. In the vehicle body position detection device according to the embodiment, the correction value calculation means (12) sets 1 as the value of the variable correction coefficient when the sum is equal to or less than the second threshold.

[0077] According to the vehicle body position detection device according to configuration 9, it is possible to calculate the correction value using the correction coefficient determined according to the driving condition of the vehicle.

[0078] Configuration 10. In the vehicle body position detection device according to the embodiment, the pitch angle estimator (13) calculates an estimate of a current pitch angle using a detection value of the velocity by the speed sensor (2), a detection value of an x-axis acceleration by the detection unit (3) and a previous estimate of the pitch angle.

[0079] According to the vehicle body position detection device according to configuration 10, it is possible to calculate the estimated value of the current pitch angle based on the detection values ​​of the speed sensor and the detection unit (inertial sensor unit) and the previous estimated value of the pitch angle.

[0080] Configuration 11. In the vehicle body position detection device according to the embodiment, the roll angle velocity estimator (11) calculates an estimate of a current roll angle velocity using each of the detection values ​​of an x-axis angular velocity and a z-axis angular velocity by the detection unit, a previous estimate of the roll angle and a previous estimate of the pitch angle by the pitch angle estimator.

[0081] According to the vehicle body position detection device according to configuration 11, it is possible to calculate the estimated value of the current roll angle velocity using the detection value of the detection unit, the previous estimated value of the roll angle and the previous estimated value of the pitch angle.

[0082] Configuration 12. A semi-trailer-type vehicle according to the embodiment includes the vehicle body position detection device according to one of the configurations 1 to 11 described above.

[0083] According to the semi-trailer-type vehicle according to configuration 12, it is possible to provide the semi-trailer-type vehicle which includes the vehicle body position detection device which is able to estimate the roll angle by setting the variable correction coefficient in such a way that the correction value decreases according to an increase in the rate of change of the angular velocity which indicates the driving state of the vehicle.

[0084] The invention is not limited to the preceding embodiments and various variations / modifications are possible within the spirit of the invention.

[0085] This application claims priority over Japanese patent application No. 2019-177713, filed on September 27, 2019, which is hereby incorporated by reference.

[0086] A vehicle body attitude detection device comprises: a correction value calculator, which sequentially calculates a correction value for estimating a vehicle body roll angle based on a variable correction coefficient determined according to a state determination calculator and detection values ​​from a speed sensor and a detection unit; and a roll angle estimation calculator, which calculates an estimate of a current vehicle body roll angle by integrating a value obtained by correcting an estimate of a roll angle velocity based on the correction value. The correction value calculator sets the variable correction value such that the correction value decreases when the parameter exceeds a threshold. REFERENCE MARK LIST 1 Vehicle body position detection device 2 Vehicle speed sensors 3 inertial sensor unit 11 Roll angle velocity estimation device 12 Correction value calculation device (condition determination unit) 13 Pitch Angle Estimator 14 Roll angle estimation calculation device

Claims

[1] Vehicle body position detection device, which sequentially estimates a roll angle of a vehicle body of a semi-trailer type vehicle, which has an x-axis extending in a longitudinal direction of the vehicle body, a y-axis extending in a width direction of the vehicle body and a z-axis extending in a vertical direction of the vehicle body, as a coordinate system fixed to the vehicle body, wherein the vehicle body position detection device comprises: a speed sensor which detects the speed of the vehicle body in a direction of travel; a detection unit comprising a plurality of acceleration sensors corresponding to axes, which detect translational acceleration in directions of the x-axis, the y-axis and the z-axis, and a plurality of angular velocity sensors corresponding to axes, which detect angular velocity in a direction about the x-axis and angular velocity in a direction about the z-axis; a pitch angle estimator that sequentially estimates the pitch angle of the vehicle body; a roll angular velocity estimator that sequentially estimates the roll angular velocity of the vehicle body; a state determination device which determines a driving state of the semi-trailer-type vehicle by comparing a parameter calculated on the basis of a detection value detected by the detection unit with a threshold value; a correction value calculation tool which sequentially calculates a correction value for estimating a roll angle of the vehicle body based on a variable correction coefficient determined according to the determination of the state determination tool and detection values ​​from the speed sensor and the detection unit; and a roll angle estimation tool which calculates an estimate of a current roll angle of the vehicle body by integrating a value obtained by correcting the estimate of the roll angle velocity on the basis of the correction value, characterized by , that The correction value calculation method sets the variable correction coefficient in such a way that the correction value decreases when the parameter exceeds the threshold. [2] Vehicle body position detection device according to claim 1, characterized by, that the correction value calculation means calculates the correction value using the variable correction coefficient, a detection value of the velocity by the velocity sensor, each of the detection values ​​of the z-axis angular velocity and the y-axis acceleration by the detection unit, a previous estimate of the roll angle and a previous estimate of the pitch angle. [3] Vehicle body position detection device according to claim 1 or 2, characterized by , that the correction value calculation means calculates a rate of change over time of the angular velocity detected by the detection unit in the direction around the z-axis as the parameter, records a first threshold as the threshold value and determines the variable correction coefficient based on a comparison between the rate of change over time and the first threshold value. [4] Vehicle body position detection device according to claim 3, characterized by , that the correction value calculation means sets the value of the variable correction coefficient to zero in order to set the correction value to zero when the rate of change over time exceeds the first threshold. [5] Vehicle body position detection device according to one of claims 2 to 4, further comprising a storage means which stores a rate of change of the angular velocity in the direction about the z-axis and a value of the variable correction coefficient, characterized by , that the correction value calculation means captures the variable correction coefficient from the storage medium according to the rate of change over time and outputs a correction value multiplied by the variable correction coefficient captured from the storage medium. [6] Vehicle body position detection device according to claim 5, characterized by, that the storage medium stores the variable correction coefficient, which is set such that its value decreases in accordance with an increase in the rate of change over time. [7] Vehicle body position detection device according to claim 1 or 2, characterized by , that the correction value calculation means calculates a sum of detection values ​​of the majority of accelerometers detected by the detection unit as the parameter, records a second threshold as the threshold value, and determines the variable correction coefficient based on a comparison between the sum and the second threshold value. [8] Vehicle body position detection device according to claim 7, characterized by , that the correction value calculation means sets the value of the variable correction coefficient to zero in order to set the correction value to zero if the sum exceeds the second threshold. [9] Vehicle body position detection device according to claim 7, characterized by , that the correction value calculation means 1 is set as the value of the variable correction coefficient if the sum is equal to or less than the second threshold. [10] Vehicle body position detection device according to claim 1, characterized by , that the pitch angle estimator calculates an estimate of a current pitch angle using a detection value of velocity by the velocity sensor, a detection value of x-axis acceleration by the detection unit, and a previous estimate of the pitch angle. [11] Vehicle body position detection device according to claim 1, characterized by, that the roll angular velocity estimator calculates an estimate of a current roll angular velocity using each of the detection values ​​of an x-axis angular velocity and a z-axis angular velocity by the detection unit, a previous estimate of the roll angle and a previous estimate of the pitch angle by the pitch angle estimator. [12] Semi-trailer-type vehicle, characterized by , that it comprises the vehicle body position detection device according to any one of claims 1 to 11.

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