control device

Abstract

It can detect road freezing with relatively high accuracy. [Solution] The control device (10) includes an acquisition means (12) for acquiring detection results from a sensor (11) which has a transmitter (111) that irradiates terahertz waves onto the road surface on which the vehicle (1) is traveling, and a receiver (112) that receives terahertz waves reflected by the road surface, and a determination means (13) for determining the freezing state of the road surface based on the acquired detection results.

Description

Technical Field

[0001] The present invention relates to the technical field of a control device for controlling a vehicle.

Background Art

[0002] As this type of device, for example, a device that predicts the freezing possibility of a road from traffic information and weather information has been proposed (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is room for improvement in the technology described in Patent Document 1 in terms of the prediction accuracy of the freezing possibility.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a control device capable of detecting road freezing with relatively high accuracy.

Means for Solving the Problems

[0006] A control device according to an aspect of the present invention includes an acquisition unit that acquires detection results of a sensor having a transmitter that irradiates terahertz waves onto the road surface of a road on which the host vehicle is traveling, and a receiver that receives the terahertz waves reflected by the road surface, and a determination unit that determines the frozen state of the road surface based on the acquired detection results.

Brief Description of the Drawings

[0007] [Figure 1] It is a block diagram showing the configuration of a control device according to an embodiment. [Figure 2]This is a flowchart showing the operation of the control device according to the embodiment. [Modes for carrying out the invention]

[0008] Embodiments relating to the control device will be described with reference to Figures 1 and 2.

[0009] (Control device configuration) The configuration of the control device 10 according to this embodiment will be described with reference to Figure 1. In Figure 1, the control device 10 is mounted on a vehicle 1. The control device 10 includes a sensor 11, a control and data collection device 12, a computing device 13, and an in-vehicle monitor 14. The sensor 11 has a terahertz wave transmitter 111 and a terahertz wave receiver 112.

[0010] The control and data collection device 12 controls the transmitter 111 to irradiate the road surface on which the vehicle 1 is traveling with terahertz waves. The receiver 112 receives at least a portion of the terahertz waves reflected by the road surface. The control and data collection device 12 collects detection information (i.e., data) regarding the detection results of the receiver 112. In other words, the control and data collection device 12 obtains the detection results of the sensor 11.

[0011] The control and collection device 12 controls the transmitter 111 to irradiate the road surface with a first terahertz wave having a first frequency and a second terahertz wave having a second frequency different from the first frequency. Here, the reflectivity of the first terahertz wave on a wet road surface is greater than that of the first terahertz wave on a frozen road surface. The reflectivity of the first terahertz wave on a wet road surface is about the same as that of the first terahertz wave on a dry road surface. The reflectivity of the second terahertz wave on a wet road surface is less than that of the second terahertz wave on a frozen road surface. The reflectivity of the second terahertz wave on a frozen road surface is less than that of the second terahertz wave on a dry road surface.

[0012] The computing unit 13 may include, for example, at least one of a CPU (Central Processing Unit) and a GPU (Graphics Processing Unit). The computing unit 13 acquires the detection information from the control and data acquisition device 12. Based on the detection information, the computing unit 13 determines the freezing condition of the road surface. If the computing unit 13 determines that the road surface is frozen, the vehicle monitor 14 notifies the user of vehicle 1 that the road surface is frozen.

[0013] (Operation of the control device) Next, the operation of the control device 10 will be explained with reference to the flowchart in Figure 2. In Figure 2, the control device 10 measures the road surface condition using the sensor 11 (step S101). Specifically, the control and collection device 12 controls the transmitter 111 to irradiate the road surface of the road on which the vehicle 1 is traveling with terahertz waves, and also collects detection information regarding the detection results of the receiver 112.

[0014] The arithmetic unit 13 determines whether the reflectance of the first terahertz wave based on the detection information is less than a first predetermined value (step S102). As described above, the reflectance of the first terahertz wave on a wet road surface is greater than the reflectance of the first terahertz wave on a frozen road surface. The first predetermined value may be a value between the reflectance of the first terahertz wave on a wet road surface and the reflectance of the first terahertz wave on a frozen road surface. The reflectance of the terahertz wave may be calculated based on the intensity of the terahertz wave transmitted from the transmitter 111 and the intensity of the terahertz wave received by the receiver 112.

[0015] If, during the process in step S102, it is determined that the reflectance of the first terahertz wave is not less than a first predetermined value (step S102: No), the operation shown in Figure 2 is terminated. In this case, the arithmetic unit 13 may determine that the road surface is not frozen.

[0016] In the process of step S102, if it is determined that the reflectance of the first terahertz wave is smaller than a first predetermined value (step S102: Yes), the arithmetic unit 13 determines whether the reflectance of the second terahertz wave based on the detection information is smaller than a second predetermined value and larger than a third predetermined value (step S103). As described above, the reflectance of the second terahertz wave on a frozen road surface is smaller than the reflectance of the second terahertz wave on a dry road surface. The second predetermined value may be a value between the reflectance of the second terahertz wave on a frozen road surface and the reflectance of the second terahertz wave on a dry road surface. Also, the reflectance of the second terahertz wave on a wet road surface is smaller than the reflectance of the second terahertz wave on a frozen road surface. The third predetermined value may be a value between the reflectance of the second terahertz wave on a wet road surface and the reflectance of the second terahertz wave on a frozen road surface.

[0017] In step S103, if it is determined that the reflectance of the second terahertz wave is not less than a second predetermined value, or if it is determined that the reflectance of the second terahertz wave is not greater than a third predetermined value (step S103: No), the operation shown in Figure 2 is terminated. In this case, the arithmetic unit 13 may determine that the road surface is not frozen.

[0018] In step S103, if it is determined that the reflectance of the second terahertz wave is less than a second predetermined value and greater than a third predetermined value (step S103: Yes), the computing unit 13 determines that the road surface is frozen (in other words, there is ice on the road surface) (step S104). The computing unit 13 controls the in-vehicle monitor 14 to display information indicating that the road surface is frozen (step S105). Note that the processing in step S102 may be performed after the processing in step S103.

[0019] (Technical effects) The control device 10 measures road surface conditions using terahertz waves. For example, compared to predicting road surface conditions from traffic information and weather information, the control device 10 can detect road surface freezing with high accuracy.

[0020] (Modified Example) By using the reflectance of the above-described first terahertz wave and second terahertz wave, it is possible to determine not only a frozen road surface but also a dry road surface and a wet road surface. The arithmetic unit 13 may determine the road surface condition based on the detection result of the sensor 11. The arithmetic unit 13 may control the behavior of the vehicle 1 based on the determined road surface condition. For example, the arithmetic unit 13 may set an appropriate tire drive torque based on the determined road surface condition. For example, the arithmetic unit 13 may activate a safety function of the vehicle 1 for avoiding at least one of sudden braking and sudden steering based on the determined road surface condition. Note that the arithmetic unit 13 according to the modified example may be realized by an ECU (Electronic Control Unit) for controlling the vehicle 1.

[0021] Note that the arithmetic unit 13 may transmit information indicating that the road surface is frozen to the road management center by using the communication function of the vehicle 1. In this case, the management center may distribute information indicating that the road surface is frozen to other vehicles existing in a predetermined range including the position of the vehicle 1.

[0022] Aspects of the invention derived from the embodiments and modified examples described above will be described below.

[0023] A control device according to one aspect of the invention includes an acquisition unit that acquires a detection result of a sensor having a transmitter that irradiates a terahertz wave to a road surface of a road on which the host vehicle is traveling and a receiver that receives the terahertz wave reflected by the road surface, and a determination unit that determines a frozen state of the road surface based on the acquired detection result. In the above-described embodiment, the "control and collection device 12" corresponds to an example of the "acquisition unit", and the "arithmetic unit 13" corresponds to an example of the "determination unit".

[0024] In an example of the control device, the transmitter may irradiate the road surface with a first terahertz wave having a first frequency and a second terahertz wave having a second frequency different from the first frequency.

[0025] In this case, the reflectivity of the first terahertz wave on a wet road surface may be greater than the reflectivity of the first terahertz wave on a frozen road surface, and the reflectivity of the second terahertz wave on a wet road surface may be less than the reflectivity of the second terahertz wave on a frozen road surface.

[0026] In another example of the control device, the determination means may include a notification means for notifying the vehicle user that the road surface is frozen if the determination means determines that the road surface is frozen. In the above embodiment, the "in-vehicle monitor 14" corresponds to an example of the "notification means".

[0027] The present invention is not limited to the embodiments described above, and can be modified as appropriate without contradicting the gist or idea of ​​the invention as can be read from the claims and specification as a whole. Control devices with such modifications are also included within the technical scope of the present invention. [Explanation of Symbols]

[0028] 1...Vehicle, 10...Control device, 11...Sensor, 12...Control and data collection device, 13...Computation unit, 14...In-vehicle monitor, 111...Transmitter, 112...Receiver

Claims

1. An acquisition means for acquiring detection results from a sensor having a transmitter that irradiates terahertz waves onto the road surface on which the vehicle is traveling, and a receiver that receives terahertz waves reflected by the road surface, A determination means for determining the freezing state of the road surface based on the acquired detection results, A control device equipped with the following features.

2. The transmitter emits a first terahertz wave having a first frequency and a second terahertz wave having a second frequency different from the first frequency onto the road surface. The control device according to claim 1.

3. The reflectivity of the first terahertz wave on a wet road surface is greater than the reflectivity of the first terahertz wave on a frozen road surface. The reflectivity of the second terahertz wave on a wet road surface is lower than the reflectivity of the second terahertz wave on a frozen road surface. The control device according to claim 2.

4. If the determination means determines that the road surface is frozen, it includes a notification means for notifying the vehicle user that the road surface is frozen. The control device according to claim 1.

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