Bump detection device

Abstract

To provide a bump detection device that can be implemented with a low-cost and simple structure.SOLUTION: A bump detection device 14: acquires motor torque of a motor connected to a tire, tire angular acceleration, motor angular acceleration, and speed information of a vehicle 1; calculates a horizontal force exerted on the tire when the tire climbs over a bump; and estimates a bump height according to the horizontal force, based on bump information, which associates a peak of horizontal tire longitudinal force before and after the tire climbs over a bump on a road surface with a bump height, the association having been pre-calculated for each speed of the vehicle 1, and on speed information.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a step detection device.

Background Art

[0002] Patent Document 1 discloses a technique for detecting a step on a road surface based on the detection results of a detection sensor that detects the distance and orientation to the road surface.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in Patent Document 1, since a distance measuring sensor is used to detect the step on the road surface, a separate distance measuring sensor for detecting the step on the road surface has to be provided, and it cannot be provided at low cost.

[0005] The present disclosure has been made in view of the above, and an object thereof is to provide a step detection device that can have an inexpensive and simple configuration.

Means for Solving the Problems

[0006] In order to solve the above-described problems and achieve the object, a step detection device according to the present disclosure is a step detection device that detects a step on a road surface on which a vehicle travels, and includes a processor. The processor acquires a motor torque of a motor connected to a tire, a tire angular acceleration, a motor angular acceleration, and speed information of the vehicle, calculates a horizontal force acting on the tire when the tire rides over the step, and based on step information associating a peak of a horizontal tire front-rear force before and after the tire rides over a road surface step and a step height calculated in advance for each speed of the vehicle and the speed information, estimates a step height corresponding to the horizontal force.

Effect of the Invention

[0007] According to the present disclosure, there is an effect that an inexpensive and simple configuration can be achieved.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Mode for Carrying Out the Invention

[0009] Hereinafter, a vehicle including a step detection device according to an embodiment of the present disclosure will be described with reference to the drawings. Note that the components in the following embodiments include those that can be replaced and are easy for those skilled in the art, or those that are substantially the same. Also, each drawing referred to in the following description only schematically shows the shape, size, and positional relationship to the extent that the content of the present disclosure can be understood. That is, the present disclosure is not limited only to the shape, size, and positional relationship illustrated in each drawing.

[0010] 〔Configuration of Vehicle〕 FIG. 1 is a block diagram showing the functional configuration of a vehicle according to an embodiment. The vehicle 1 shown in FIG. 1 is assumed to be an HEV (Hybrid Electric Vehicle), PHEV (Plug-in Hybrid Electric Vehicle), BEV (Battery Electric Vehicle), FCEV (Fuel Cell Electric Vehicle), etc. equipped with a motor and an engine.

[0011] As shown in FIG. 1, the vehicle 1 includes various sensors 11, a transmission unit 12, a recording unit 13, and a step detection device 14.

[0012] The various sensors 11 detect the motor torque of the motor connected to the tire, the tire angular acceleration (rotational speed), the motor angular acceleration (resolver signal), the gear ratio of the motor and the tire, and the speed information of the vehicle 1. Here, the motor is assumed to be an MG (Motor Generator), a rotating electrical machine, a drive machine, an electric motor, and a motor generator. The various sensors 11 are composed of a wheel degree sensor that detects the wheel angular acceleration of the wheels (not shown) of the vehicle 1, a speed sensor that detects the speed of the vehicle 1, an acceleration sensor that detects the acceleration of the vehicle 1, a rotation angle sensor that detects the motor angular acceleration of the motor (not shown) of the vehicle 1, for example, a resolver or a rotary encoder, a torque sensor that detects the torque of the motor, and a gyro sensor, etc. Further, the various sensors 11 are composed of a GPS (Global Positioning System) sensor, etc. that detects the position information of the vehicle 1.

[0013] The transmission unit 12 transmits various information to an external server or another vehicle via a network under the control of the step detection device 14. The transmission unit 12 is configured using a predetermined communication standard, for example, Wi-Fi (registered trademark), Bluetooth (registered trademark), or 5G (5th Generation Mobile Communication System), etc.

[0014] The recording unit 13 is configured using a HDD (Hard Disk Drive), SSD (Solid State Drive), flash memory, volatile memory, non-volatile memory, and the like. The recording unit 13 includes a program recording unit 131 and a step information recording unit 132. The program recording unit 131 records various programs executed by the vehicle 1 and the step detection device 14 and data during processing. The step information recording unit 132 records step information in which the peak of the horizontal tire longitudinal force before and after the tire has climbed over a step calculated in advance for each speed of the vehicle 1 is associated with the step height.

[0015] Here, the step information recorded by the step information recording unit 132 will be described. FIG. 2 is a diagram showing an example of the step information recorded by the step information recording unit 132. In FIG. 2, each of the straight lines L1 to L3 shows the relationship between the peak of the horizontal tire longitudinal force before and after the tire has climbed over a road surface step and the step height based on the speed. In FIG. 2, the straight line L1 shows the relationship between the peak of the tire longitudinal force when the speed is 40 km / h and the step height, the straight line L2 shows the relationship between the peak of the tire longitudinal force when the speed is 30 km / h and the step height, and the straight line L3 shows the relationship between the peak of the tire longitudinal force when the speed is 20 km / h and the step height.

[0016] As shown by the straight lines L1 to L3 shown in FIG. 2, the step information has a slope that changes according to the speed of the vehicle. Here, the step refers to a depression, a rut, a groove, unevenness, and the like. Further, the peak of the tire longitudinal force is the maximum value of the difference between the horizontal force acting on the tire when the tire climbs over a road surface step, which will be described later, and the horizontal force acting on the tire before the tire climbs over the step. Furthermore, the step height (step amount) is the difference (amount) before and after the tire climbs over the step. In FIG. 2, it is for each speed, but the relationship between the peak of the tire longitudinal force and the step height may be obtained in advance for each tire diameter and vehicle type and included in the step information.

[0017] Returning to FIG. 1, the description of the configuration of the vehicle 1 will be continued. The step detection device 14 is configured by an ECU (Electronic Control Unit) using a processor having hardware such as a memory and a CPU (Central Processing Unit). The step detection device 14 includes an acquisition unit 141, a calculation unit 142, a determination unit 144, and a communication control unit 145.

[0018] The acquisition unit 141 acquires data from various sensors 11. Specifically, the acquisition unit 141 acquires data including the wheel angular acceleration, motor angular acceleration, motor torque, vehicle speed information of the vehicle 1, and position information of the vehicle 1 detected by the various sensors 11 from the various sensors 11.

[0019] The calculation unit 142 calculates the horizontal force acting on the tire when the tire provided on the vehicle 1 rides over a step on the road surface. The calculation method calculated by the calculation unit 142 will be described later.

[0020] Based on the step information and speed information in which the peak of the horizontal tire longitudinal force before and after the tire of the vehicle 1 rides over a step on the road surface, which is calculated in advance for each speed of the vehicle 1, and the step height are associated with each other, the estimation unit 143 estimates the step height corresponding to the horizontal force.

[0021] The determination unit 144 determines whether or not the step height estimated by the estimation unit 143 is equal to or greater than a predetermined value. Here, the predetermined value is a value that hinders the running of the vehicle 1. The predetermined value may be set appropriately by the user or by the manufacturer.

[0022] The communication control unit 145 causes the transmission unit 12 to transmit, via a network, transmission information in which the position information of the vehicle 1 acquired by the acquisition unit 141 and the step height estimated by the estimation unit 143 are associated with each other to a server or another vehicle.

[0023] 〔Processing of the step detection device〕 Next, the processing executed by the step detection device 14 will be described. FIG. 3 is a flowchart showing an outline of the processing executed by the step detection device 14.

[0024] As shown in FIG. 3, the acquisition unit 141 acquires data from various sensors 11 (step S101). Specifically, the acquisition unit 141 acquires data including the wheel angular acceleration, motor angular acceleration, motor torque, vehicle speed information of the vehicle 1, and position information of the vehicle 1 detected by the various sensors 11 from the various sensors 11.

[0025] Subsequently, based on the data acquired by the acquisition unit 141, the calculation unit 142 calculates the horizontal force F acting on the tire when the tire of the vehicle 1 rides over a step existing on the road surface. x is calculated based on the following formula (1) (step S102). Specifically, as shown in FIG. 4, based on the data acquired by the acquisition unit 141, the calculation unit 142 calculates the horizontal force F acting on the tire 100 of the vehicle 1 when the tire 100 rides over a step 200 existing on the road surface (see arrow A1). x is calculated based on the following formula (1).

Equation

[0026] Subsequently, based on the step information recorded by the step information recording unit 132 and the horizontal force F calculated by the calculation unit 142, the estimation unit 143 estimates the step height of the road surface on which the vehicle 1 is traveling (step S103). Specifically, based on the vehicle speed information included in the data acquired by the acquisition unit 141 and the step information recorded by the step information recording unit 132, the estimation unit 143 calculates the horizontal force F calculated by the calculation unit 142 using formula (1). x xEstimate the step height according to the situation. For example, when the speed information of the vehicle 1 is 40 km / h, the estimation unit 143 refers to the straight line L1 of the step information recorded by the step information recording unit 132, and the horizontal force F calculated by the calculation unit 142 using the formula (1) x Estimate the step height corresponding to the peak of the front and rear tire forces according to, and regard it as the step height of the road surface on which the vehicle 1 is traveling.

[0027] Subsequently, the determination unit 144 determines whether the step height estimated by the estimation unit 143 is equal to or greater than a predetermined value (step S104). When it is determined by the determination unit 144 that the step height estimated by the estimation unit 143 is equal to or greater than the predetermined value (step S104: Yes), the step detection device 14 proceeds to step S105 described later. On the contrary, when it is determined by the determination unit 144 that the step height estimated by the estimation unit 143 is not equal to or greater than the predetermined value (step S104: No), the step detection device 14 ends this process.

[0028] In step S105, the communication control unit 145 causes the transmission unit 12 to transmit the transmission information including the position information of the vehicle 1 acquired by the acquisition unit 141 and the step height estimated by the estimation unit 143 to the server or another vehicle via the network. After step S105, the step detection device 14 ends this process.

[0029] According to the above-described embodiment, based on the speed information of the vehicle 1 included in the data acquired by the acquisition unit 141 by the estimation unit 143 and the step information recorded by the step information recording unit 132, the horizontal force F calculated by the calculation unit 142 x Estimate the step height according to, without the need for an additional camera or the like separately, and it can be inexpensive and simple.

[0030] Also, according to one embodiment, when the determination unit 144 determines that the step height estimated by the estimation unit 143 is equal to or greater than a predetermined value, the communication control unit 145 causes the transmission unit 12 to transmit, via the network, transmission information including the position information of the vehicle 1 acquired by the acquisition unit 141 and the step height estimated by the estimation unit 143 to the server or another vehicle. As a result, the other vehicle can select an optimal driving route when selecting a driving route to travel, and can prevent the lower surface of the vehicle from being scratched or damaged or becoming unable to escape due to the step on the road surface.

[0031] In the description of the flowchart in this specification, expressions such as "first", "subsequently", and "then" are used to clarify the order of processing between steps. However, the order of processing necessary to implement this embodiment is not uniquely determined by these expressions. That is, the order of processing in the flowchart described in this specification can be changed within a range without contradiction.

[0032] Further effects and modifications can be easily derived by those skilled in the art. The broader aspects of the present invention are not limited to the specific details and representative embodiments described and represented as above. Therefore, various changes can be made without departing from the spirit or scope of the general inventive concept defined by the appended claims and their equivalents.

[0033] As described above, some embodiments of the present application have been described in detail based on the drawings. However, these are examples, and the present invention can be implemented in other forms with various modifications and improvements based on the knowledge of those skilled in the art, including the aspects described in the disclosure column of the present invention.

Explanation of Reference Numerals

[0034] 1 Vehicle 11 Various Sensors 12 Transmission Unit 13 Recording Unit 14 Step Detection Device 131 Program Recording Unit 132 Step Information Recording Unit 141 Acquisition unit 142 Calculation unit 143 Estimation unit 144 Judgment unit 145 Communication control unit

Claims

1. A step detection device for detecting a step on a road surface on which a vehicle travels, comprising a processor, wherein the processor acquires motor torque of a motor connected to a tire, tire angular acceleration, motor angular acceleration, and speed information of the vehicle, calculates a horizontal force acting on the tire when the tire climbs over the step, estimates a step height corresponding to the horizontal force based on step information associating a peak of horizontal tire front-rear forces before and after the tire climbs over a road surface step and the step height calculated in advance for each speed of the vehicle and the speed information, a step detection device.

2. The step detection device according to claim 1, wherein the processor determines whether the estimated step height is equal to or greater than a predetermined value, and when it is determined that the estimated step height is equal to or greater than the predetermined value, transmits the estimated step height to the outside, a step detection device.

3. The step detection device according to claim 2, wherein the processor acquires position information of the vehicle's travel, and when it is determined that the estimated step height is equal to or greater than the predetermined value, transmits transmission information associating the position information with the estimated step height to the outside, a step detection device.

Images