Control device

Abstract

To prevent the occurrence of an area having a possibility that the intensity of an electromagnetic wave may become too strong or an erroneous signal may be detected when a detection range is widened using a plurality of sensors.SOLUTION: An irradiation system (100) includes a plurality of irradiation devices (1) and a control device (2). The plurality of irradiation devices (1) are arranged adjacent to each other in a first direction. Each of the irradiation devices (1) can move an electromagnetic wave in a first direction and in a second direction different from the first direction. The control device (2) controls the plurality of irradiation devices. Particularly, the control device (2) causes the control device and the positions of electromagnetic wave irradiation performed by the plurality of irradiation devices (1) at a predetermined timing to be separated by at least a predetermined distance or more in the second direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a control device. [Background technology]

[0002] In recent years, sensors that irradiate electromagnetic waves such as light and detect the reflected waves are installed on moving objects such as vehicles, and the detection results of these sensors are used to control the moving objects. In sensors for such applications, the emitted electromagnetic waves are transmitted using devices such as MEMS (Micro Electro Mechanical Systems).

[0003] An example of a device for moving electromagnetic waves is described in Patent Document 1. The device described in Patent Document 1 has a movable reflecting mirror. This reflecting mirror vibrates due to an electrostatic force generated between electrodes. This electrostatic force is controlled by a voltage applied to the electrodes. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-167254 Summary of the Invention [Problem to be solved by the invention]

[0005] When a movable reflecting mirror is used to move the electromagnetic waves, the reflecting mirror moves the irradiation position of the electromagnetic waves in a first direction while also moving it in a second direction different from the first direction. On the other hand, to expand the detection range, multiple sensors may be used in parallel. In this case, the detection ranges of multiple sensors are aligned, but the edges of adjacent detection ranges must overlap to prevent gaps between them. This may result in the electromagnetic wave intensity being too strong in the overlapping area. Furthermore, in the overlapping area, it may be impossible to distinguish whether the received signal accompanying the reflected wave from the target is a signal due to the electromagnetic wave emitted by the sensor itself or an electromagnetic wave emitted by an adjacent sensor, resulting in the detection of an incorrect signal.

[0006] One example of the problem that the present invention aims to solve is how to prevent areas from being created where the electromagnetic wave intensity is too strong or where erroneous signals may be detected when multiple sensors are used to expand the detection range. [Means for solving the problem]

[0007] The invention described in claim 1 is a control device that controls a plurality of irradiation devices arranged adjacent to each other in a first direction, each of the plurality of irradiation devices is capable of moving an irradiation position of an electromagnetic wave in the first direction while also moving in a second direction different from the first direction; The control device controls the irradiation positions of the electromagnetic waves from each of the plurality of irradiation devices at a predetermined timing to be at least a predetermined distance apart in the second direction.

[0008] One example of the present invention is a system including: a control device that controls the plurality of irradiation devices; Equipped with each of the plurality of irradiation devices is capable of moving an irradiation position of an electromagnetic wave in the first direction while also moving in a second direction different from the first direction; The control device is an irradiation system that controls the irradiation positions of the electromagnetic waves from each of the plurality of irradiation devices at a predetermined timing so that they are separated by at least a predetermined distance in at least a second direction.

[0009] One example of the present invention is a control method used in a control device that controls a plurality of irradiation devices arranged adjacent to each other in a first direction, the method comprising: each of the plurality of irradiation devices is capable of moving an irradiation position of an electromagnetic wave in the first direction while also moving in a second direction different from the first direction; The control method includes a step of controlling the positions of the electromagnetic waves irradiated by each of the plurality of irradiation devices at a predetermined timing to be at least a predetermined distance apart in the second direction.

[0010] One example of the present invention is a program for causing a computer to function as a control device that controls an irradiation device, comprising: the irradiation device is capable of moving an irradiation position of the electromagnetic wave in the first direction while also moving in a second direction different from the first direction, The computer, a function of storing information indicating how much the irradiation position of the electromagnetic wave is shifted from a reference in the second direction; a function of receiving the reference in the second direction and controlling the irradiation direction of the electromagnetic wave using the received reference and the stored information; It is a program that allows you to have the following. [Brief explanation of the drawings]

[0011] The above-mentioned objects, as well as other objects, features and advantages, will become more apparent from the preferred embodiments described below and the accompanying drawings.

[0012] [Figure 1] FIG. 1 is a diagram illustrating a configuration of an illumination system according to an embodiment. [Figure 2] FIG. 2 is a diagram for explaining the range of light irradiation by the irradiation system. [Figure 3] FIG. 2 is a diagram for explaining an example of control by a control device. [Figure 4] 5A and 5B are diagrams illustrating an example of control by a control device. [Figure 5] FIG. 10 is a diagram for explaining a first method for linking a plurality of control units. [Figure 6] FIG. 10 is a diagram for explaining a second method for linking a plurality of control units. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, like components are designated by like reference numerals, and the description thereof will be omitted as appropriate.

[0014] (Embodiment) FIG. 1 is a diagram showing the configuration of an irradiation system 100 according to an embodiment. The irradiation system 100 according to this embodiment includes a plurality of irradiation devices 1 and a control device 2. The plurality of irradiation devices 1 are arranged adjacent to each other in a first direction. Each of the plurality of irradiation devices 1 is capable of moving an irradiation position of an electromagnetic wave in the first direction and also in a second direction different from the first direction. The control device 2 controls the plurality of irradiation devices. In detail, the control device 2 controls the irradiation positions of the electromagnetic waves emitted by each of the plurality of irradiation devices 1 at a predetermined timing so that they are at least a predetermined distance apart in the second direction from the control device. In this embodiment, the control unit 30, which is a part of the irradiation device 1, is also a part of the control device 2. The irradiation system 100 will be described in detail below.

[0015] The illumination system 100 is mounted on a moving body such as a vehicle. As described above, the illumination system 100 includes a plurality of illumination devices 1. The illumination device 1 includes an illuminator 10, a movable reflector 20, and a control unit 30. As described above, the control unit 2 includes the movable reflector 20 and the control unit 30 of the plurality of illumination devices 1. The illumination device 1 is, for example, a LIDAR (Light Detection And Ranging) or millimeter-wave radar, and detects the relative position of an object located around the moving body when the moving body is used as a reference. In this case, the illumination device 1 also includes a photoreceiver.

[0016] The irradiator 10 irradiates electromagnetic waves such as light. When the irradiator 10 irradiates light, the irradiator 10 is, for example, a semiconductor laser such as a laser diode, and emits laser light when electrical energy is input. The control unit 30 controls the power input to the irradiator 10, thereby controlling the light emission timing and light emission intensity of the irradiator 10. The following description will be given assuming that the electromagnetic waves irradiated by the irradiator 10 are light.

[0017] The movable reflector 20 has at least one movable mirror and can change the irradiation direction of the light emitted by the illuminator 10 in two dimensions. When the movable reflector 20 has one movable mirror, the tilt of this movable mirror can be changed around each of two axes that are perpendicular to each other. When the movable reflector 20 has two movable mirrors, the axes of the two movable mirrors are perpendicular to each other.

[0018] The tilt of the movable mirror of the movable reflector 20 can be controlled, for example, by a voltage input to the movable reflector 20. This voltage is controlled by the control unit 30. Specifically, the voltage input to the movable reflector 20 changes periodically. This voltage is, for example, a sine wave. In this case, the direction of reflection of light by the movable reflector 20 changes periodically, for example, in a sine wave pattern.

[0019] The control unit 30 is realized using, for example, an integrated circuit. This integrated circuit has, for example, a bus, a processor, a memory, a storage device, an input / output interface, and a network interface. The bus is a data transmission path through which the processor, memory, storage device, input / output interface, and network interface transmit and receive data to and from each other. However, the method of connecting the processors and the like to each other is not limited to bus connection. The processor is an arithmetic processing unit realized using, for example, a microprocessor. The memory is a memory realized using, for example, RAM (Random Access Memory). The storage device is a storage device realized using, for example, ROM (Read Only Memory), flash memory, etc.

[0020] The input / output interface is an interface for connecting the integrated circuit to peripheral devices, such as the illuminator 10 and the movable reflector 20.

[0021] The network interface is an interface for connecting the integrated circuit to a communication network. This communication network is, for example, a Controller Area Network (CAN) communication network. The network interface may be connected to the communication network via a wireless connection or a wired connection.

[0022] The storage device stores program modules for realizing the functions of the control unit 30. The processor reads these program modules into memory and executes them to realize the functions of the control unit 30. The program modules may also be stored in the memory. In this case, the integrated circuit does not need to include a storage device.

[0023] FIG. 2 is a diagram illustrating the range of light irradiation by the irradiation system 100. The light from the illuminator 10 is moved by controlling the movable reflector 20. Specifically, as shown in FIG. 2, the control unit 30 periodically moves the light in a first direction (H direction) and simultaneously periodically moves the light in a second direction (V direction) perpendicular to the first direction. The first direction corresponds to a first rotation axis of the movable reflector 20, and the second direction corresponds to a second rotation axis of the movable reflector 20. The movement period in the first direction is shorter than the movement period in the second direction. For example, among the signals input to the movable reflector 20, the control unit 30 uses a sine wave as a control signal for controlling movement in the first direction (H direction), and uses a signal with a longer period than the sine wave (e.g., a sawtooth wave) as a control signal for controlling movement in the second direction (V direction). Therefore, as shown in FIG. 2, the light moves periodically in the H direction (horizontal direction) in FIG. 2 while gradually moving in the V direction (horizontal direction). As a result, the control unit 30 irradiates the light onto a substantially rectangular area.

[0024] As shown in FIG. 1, the illumination system 100 includes a plurality of illumination devices 1. A light illumination range α is determined for each of the illumination devices 1. These ranges α are aligned with one another at least in a first direction (H direction). In the example shown in this figure, if the light illumination range of the first illumination device 1 is defined as a first range α1 and the light illumination range of the second illumination device 1 is defined as a second range α2, the first range α1 and the second range α2 are aligned with one another in the first direction (H direction). To prevent gaps from occurring in the light illumination ranges when the illumination system 100 is viewed as a single device, it is necessary for adjacent ranges α to overlap. For example, as shown in FIGS. 1 and 2, a portion of the first range α1 overlaps a portion of the second range α2. If the timing of light illumination by the first illumination device 1 and the timing of light illumination by the second illumination device 1 overlap in this overlapping range (hereinafter referred to as the overlapping range α3), the light illumination intensity in the overlapping range α3 may be higher than expected.

[0025] In contrast, in this embodiment, the control device 2 causes the timing of light irradiation into the overlapping range α3 to differ between the first irradiation device 1 and the second irradiation device 1. For example, the control device 2 separates the irradiation positions of electromagnetic waves from each of the multiple irradiation devices at a predetermined timing by at least a predetermined distance in the second direction. In this embodiment, the control device 2 does this at any timing (i.e., always). Specifically, as shown in FIG. 3 , the two control units 30 cause the phase in the V direction (second direction) of the movable reflector 20 of the first irradiation device 1 (corresponding to the first range α1) to differ from the phase in the V direction (second direction) of the movable reflector 20 of the second irradiation device 1 (corresponding to the second range α2).

[0026] The above-mentioned predetermined distance can also be replaced with a predetermined angle. The minimum value of this predetermined angle is determined, for example, so that the instantaneous field of view of adjacent sensors does not fall within the spread angle of any irradiated electromagnetic wave. In other words, it is the minimum predetermined angle at which the spread angles of the irradiated electromagnetic wave must be separated. This minimum predetermined angle exists in both the H direction and the V direction.

[0027] 1 illustrates two irradiation devices 1. On the other hand, if the irradiation system 100 has three or more irradiation devices 1 and the ranges α of these irradiation devices 1 are aligned in the first direction (H direction), the phase of the movable reflector 20 in the V direction (second direction) may gradually shift in the same direction (for example, the direction in which the phase advances) as the range α moves in the first direction (H direction) as shown in FIG. 4(A), or may shift so that the phase advances in a zigzag pattern as shown in FIG. 4(B). In the case of FIG. 4(B), for example, two types of phases may appear alternately.

[0028] In order to differentiate the timing of irradiating the overlapping range α3 with light from the first irradiation device 1 and the second irradiation device 1, it is necessary to link the multiple control units 30. An example of this linking method will be described below.

[0029] FIG. 5 is a diagram illustrating a first method for interlocking multiple control units 30. In the example shown in this figure, the multiple control units 30 are connected to each other via signal lines or wirelessly. One control unit 30 serves as a master (hereinafter referred to as a master control unit 30a), and the remaining control units 30 serve as slaves (hereinafter referred to as slave control units 30b). Each of the multiple slave control units 30b pre-stores information for specifying how much the phase of the movable reflector 20 controlled by that slave control unit 30b should be delayed (or advanced) in the V direction relative to the movable reflector 20 controlled by the master control unit 30a (i.e., information indicating how much it should be shifted from a reference). The master control unit 30a outputs information (i.e., a reference) specifying the phase of the movable reflector 20 controlled by the master control unit 30a to the multiple slave control units 30b. The slave control unit 30b uses the information received from the master control unit 30a and pre-stored information to specify the phase of the movable reflector 20 in the V direction.

[0030] The delay amount (or advance amount) stored in advance in the slave control unit 30b is preferably an integer multiple of the period in the H direction.

[0031] FIG. 6 is a diagram illustrating a first method for interlocking multiple control units 30. In the example shown in this figure, the irradiation system 100 includes a control unit 3 as part of the control unit 2. The control unit 3 is a device different from any of the irradiation devices 1. The control unit 3 and the multiple control units 30 are connected to each other via a signal line or wirelessly. The control unit 3 is a master and outputs a reference timing to the multiple control units 30. Each of the multiple control units 30 is a slave and stores in advance information for specifying how much the V-direction phase of the movable reflector 20 controlled by that control unit 30 should be delayed (or advanced) relative to the reference timing. The multiple control units 30 specify the V-direction phase of the movable reflector 20 using the reference timing received from the control unit 3 and the information stored in advance.

[0032] As described above, according to this embodiment, the control device 2 separates the irradiation positions of the electromagnetic waves from each of the multiple irradiation devices 1 at least by a predetermined distance in the second direction. Therefore, even if the overlapping range α3 shown in Fig. 1 occurs, the possibility that the electromagnetic waves will be irradiated from the multiple irradiation devices 1 simultaneously into the overlapping range α3 is reduced. Therefore, it is unlikely that an area will occur where the intensity of the electromagnetic waves is too strong or where an erroneous signal may be detected.

[0033] Although the embodiments and examples have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0034] This application claims priority based on Japanese Patent Application No. 2018-022812, filed February 13, 2018, the disclosure of which is incorporated herein by reference in its entirety. [Explanation of symbols]

[0035] 1 Irradiation device 2. Control device 3. Control device 10 Irradiator 20 Movable reflector 30 Control Unit 100 Irradiation System

Claims

[Claim 1] A control device that controls a plurality of irradiation devices arranged adjacent to each other in a first direction, each of the plurality of irradiation devices is capable of moving an irradiation position of an electromagnetic wave in the first direction while also moving in a second direction different from the first direction; a control device that controls the irradiation positions of the electromagnetic waves from each of the plurality of irradiation devices at a predetermined timing so that they are at least a predetermined distance apart in the second direction.

Images