Attitude estimation method and optical transmission system

Abstract

To suitably estimate the attitude of an optical input device.SOLUTION: In an optical transmission system for transmitting output light from an optical output device to an optical input device by spatial transmission, the attitude of the optical input device is estimated on the basis of power feeding light irradiation information (output light irradiation information) pertaining to a power feeding direction switching unit (optical output direction switching unit) which is actuated so as to draw a prescribed diagram on the light-receiving plane of a photoelectric conversion element by output light (power feeding light), and light reception information relating to a diagram created by connecting the positions of output light (power feeding light) detected by a light detection unit of the optical input device. The power feeding light irradiation information represents an angle (2α) at which the direction of output light (power feeding light) is switched along two direction of horizontal and the vertical directions, and the light reception information represents the lengths (a, b) of first and second lines constituting a cross shape.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an attitude estimation method and an optical transmission system, and more particularly to a technique for estimating the attitude of an optical input device in an optical transmission system that transmits light from an optical output device to an optical input device. [Background technology]

[0002] Recently, optical transmission systems that supply optical energy from a laser transmitter (optical output device, power supply device) to a power receiver (optical input device, power receiving device) have been researched. Patent Document 1 describes a technique for estimating the distance and direction from a laser transmitter to a power receiver by using a beacon provided in the receiver of the power receiver. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2022 / 0224170 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the optical transmission system of the above-mentioned conventional technology, it is difficult to estimate the attitude of the power receiver relative to the laser transmitter (eg, rotation angles around three axes, such as roll angle, pitch angle, and yaw angle, etc.).

[0005] An object of the present disclosure is to preferably estimate the attitude of an optical input device. [Means for solving the problem]

[0006] The pose estimation method according to the present disclosure includes: 1. An attitude estimation method for estimating an attitude of an optical input device in an optical transmission system in which output light is transmitted from an optical output device to an optical input device by spatial transmission, comprising the steps of: the light output device comprises a light emitting unit that outputs the output light, and a light output direction switching unit that switches the direction of the output light output by the light emitting unit to an arbitrary angle, the optical input device includes a light receiving unit having a light receiving surface that receives the output light, and a light detection unit that detects a position at which the output light hits the light receiving surface, The posture of the optical input device is inferred based on output light irradiation information that activates the light output direction switching unit to draw a predetermined figure on the light receiving surface with the output light, and received light information regarding a figure formed by connecting the positions of the output light that hit the light receiving surface detected by the light detection unit.

[0007] The optical transmission system according to the present disclosure comprises: An optical transmission system for transmitting output light from an optical output device to an optical input device by spatial transmission, comprising: the light output device includes a light emitting unit that outputs the output light, a light output direction switching unit that switches the direction of the output light output by the light emitting unit to an arbitrary angle, and a light output side communication unit that receives information from the light input device, the optical input device comprises a light receiving section having a light receiving surface for receiving the output light, a light detection section for detecting a position on the light receiving surface at which the output light hits, and an optical input side communication section for transmitting information to the optical output device, The optical output device is provided with an attitude estimation control unit that estimates the attitude of the optical input device based on output light irradiation information that activates the optical output direction switching unit so as to draw a predetermined figure on the light receiving surface with the output light, and received light information regarding a figure formed by connecting the positions of the output light detected by the optical detection unit, which is information transmitted from the optical input device. Effect of the Invention

[0008] According to the present disclosure, it becomes possible to suitably estimate the attitude of an optical input device. [Brief description of the drawings]

[0009] [Figure 1] 1 is a configuration diagram of an optical power supply system according to a first embodiment of the present disclosure. [Diagram 2] 13A and 13B are explanatory diagrams of an embodiment in which a cross shape is drawn on the light receiving surface of the light receiving unit by using feeding light. [Diagram 3] 11 is an explanatory diagram relating to a process of estimating a rotation angle of a power receiving device about a roll axis. FIG. [Figure 4] 13A and 13B are diagrams illustrating a process of estimating a rotation angle of a power receiving device about a pitch axis and a rotation angle of a power receiving device about a yaw axis, and estimating a distance between a power feeding device and a power receiving device. [Diagram 5] 13 is a flowchart of an attitude estimation process for estimating the attitude of a power receiving device. [Figure 6] FIG. 11 is a configuration diagram of an optical power supply system according to a second embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, one embodiment of the present disclosure will be described with reference to the drawings. In this disclosure, an optical power supply system will be described as an optical transmission system that transmits power supply light, which is output light.

[0011] [First embodiment] As shown in FIG. 1, an optical power supply system 1 according to the first embodiment includes a power supply device (PSE: Power Sourcing Equipment) 110 which is an optical output device, and a power receiving device (PD: Powered Device) 310 which is an optical input device. The optical power supply system 1 transmits the power supply light 112 generated by the power supply device 110 to the power receiving device 310 through space. Such an optical transmission method for space transmission is called FSP (Free Space Power). The space transmission here refers to transmission of the power supply light 112 in a state where only space exists without placing an optical fiber in the transmission section between the power supply device 110 and the power receiving device 310. The power supply device 110 in the present disclosure is a device that converts electric power into optical energy and supplies the converted energy, and the power receiving device 310 is a device that receives optical energy and converts the optical energy into electric power. It is also possible to transmit information (data) together with electric power by the power supply light 112. The optical power supply system 1 according to the present disclosure may be used for power supply purposes in which only power is supplied by the power supply light 112, or for information transmission purposes in which only information (data) is transmitted by the power supply light 112.

[0012] The power supply device 110 includes a power supply semiconductor laser 111 as a light emitting unit that outputs power supply light 112, a power supply direction switching unit 115 that is a light output direction switching unit that switches the direction of the power supply light 112 to an arbitrary angle, a position detection unit 120 that detects the position of the power receiving device 310, a power supply side communication unit 130 that is a light output side communication unit, and a power supply control unit 150. The power supply control unit 150 controls each unit of the power supply device 110. The power supply device 110 is connected to a power source, and a power supply semiconductor laser 111 and the like are electrically driven. The power supply semiconductor laser 111 oscillates with the power from the power supply and outputs power supply light 112 . The power supply device 110 then transmits power supply light 112 emitted from the power supply semiconductor laser 111 into space.

[0013] The power supply direction switching unit 115 has a function of switching the direction of the power supply light 112 outputted by the power supply semiconductor laser 111, and switches the direction of the power supply light 112 depending on the position of the power receiving device 310, etc. For example, the power supply direction switching unit 115 can be a scanning type switching unit that switches the attitude (direction) of the power supply semiconductor laser 111 by moving the stand of the light emitting unit with a horizontal axis motor and a vertical axis motor, and switches the direction of the power supply light 112 depending on the position of the target power receiving device 310. In addition, the power supply direction switching unit 115 can be a mirror-type switching unit that drives a galvanometer mirror having a horizontal axis scan mirror and a vertical axis scan mirror, and reflects the power supply light 112 outputted by the power supply semiconductor laser 111 through the cooperation of the two mirrors, thereby switching the direction of the power supply light 112 depending on the position of the target power receiving device 310. This power supply direction switching unit 115 can transmit the power supply light 112 to the power receiving device 310 by switching the direction of the power supply light 112 outputted by the power supply semiconductor laser 111 to an arbitrary angle. In particular, by operating the power supply direction switching unit 115 to switch the direction of the power supply light 112 to any angle, the power supply light 112 can be irradiated so as to draw a predetermined figure on the light receiving surface 311a (see Figure 2) of the light receiving unit of the power receiving device 310 with the power supply light 112.

[0014] The position detection unit 120 detects the position of the power receiving device 310 by, for example, measuring the distance and direction to the power receiving device 310 . 1 illustrates an example in which the power supply device 110 includes the position detection unit 120, but the position detection device as the position detection unit may be provided separately from the power supply device 110. In that case, it is preferable that the position detection device is disposed near the power supply device 110, and the position detection device and the power supply device 110 are in one-to-one correspondence.

[0015] The power supply side communication unit 130 has, for example, an antenna and a communication circuit, and communicates with the power receiving device 310 via the network N to transmit and receive various data and information.

[0016] The power supply control section 150 controls the laser oscillation of the power supply semiconductor laser 111 to control the output of the power supply light 112 . In addition, the power supply control unit 150 controls the power supply direction switching unit 115 based on the position of the power receiving device 310 detected by the position detection unit 120, and performs a process of directing the power supply light 112 outputted from the power supply semiconductor laser 111 toward the power receiving device 310. Furthermore, the power supply control unit 150 controls the power supply direction switching unit 115 based on the graphic drawing data, and executes a process of drawing a predetermined graphic on the light receiving surface 311a (see FIG. 2) of the light receiving unit of the power receiving device 310 with the power supply light 112. Note that initial values ​​related to the graphic drawing data are recorded and set in advance in a storage unit (not shown) of the power supply device 110. Furthermore, power supply control section 150 executes a process of receiving, via power supply side communication section 130, position information, which will be described later, transmitted from power receiving device 310 (power receiving side communication section 330). In addition, the power supply control unit 150 superimposes information on the power supply light 112 to transmit information (data) together with optical energy (electric power). For example, the power supply control unit 150 superimposes information converted into an optical signal on the power supply light 112.

[0017] In particular, the power supply control unit 150 executes a process of estimating the attitude of the power receiving device 310 based on power supply light irradiation information, which is output light irradiation information conforming to graphic drawing data, and light reception information conforming to position information described later. This attitude estimation control process will be described later.

[0018] The power receiving device 310 includes a photoelectric conversion element 311 as a light receiving unit that receives the power supply light 112, a light detection unit 311b that detects the position where the power supply light 112 hits a light receiving surface 311a of the photoelectric conversion element 311, a power receiving side communication unit 330 that is an optical input side communication unit, and a power receiving control unit 350. The power receiving control unit 350 controls each unit of the power receiving device 310. The photoelectric conversion element 311 receives the power supply light 112 transmitted through the air (space) and converts the power supply light 112 into electric power. The electric power converted by the photoelectric conversion element 311 is used as the driving power required in the power receiving device 310. Furthermore, the power receiving device 310 is capable of outputting the electric power converted by the photoelectric conversion element 311 to an external device.

[0019] The light detection unit 311b is provided integrally with or separately from the photoelectric conversion element 311, detects the position where the power supply light 112 hits the light receiving surface 311a of the photoelectric conversion element 311, and acquires position information within the detection area. For example, the position information is coordinate data in the detection area. For example, a PSD (Position Sensing Device) may be used as the light detection unit 311b.

[0020] The power receiving side communication unit 330 has, for example, an antenna and a communication circuit, and communicates with the power supply device 110 via the network N to transmit and receive various data and information.

[0021] The power receiving control unit 350 monitors the value of the power obtained by converting the power supply light 112 by the photoelectric conversion element 311 . In addition, the power receiving control unit 350 executes a process of transmitting position information regarding the spot where the power supply light 112 hits the light receiving surface 311a detected by the light detection unit 311b of the photoelectric conversion element 311 to the power supply device 110 (power supply side communication unit 130) via the power receiving side communication unit 330. Furthermore, the power reception control unit 350 extracts information superimposed on the power supply light 112 received by the photoelectric conversion element 311. For example, the power reception control unit 350 extracts an optical signal superimposed on the power supply light 112, converts it into information, and acquires it.

[0022] Each of the power supply semiconductor laser 111 and the photoelectric conversion element 311 is an element including a laser medium with a laser wavelength of 500 nm or less. More specifically, the semiconductor material constituting the semiconductor region that provides the light-to-electricity conversion effect of the power supply semiconductor laser 111 and the photoelectric conversion element 311 is a semiconductor having a short laser wavelength of 500 nm or less. Semiconductors having short laser wavelengths have a large band gap and high photoelectric conversion efficiency, so the photoelectric conversion efficiency on the generating side and the receiving side of the optical power supply is improved, and the optical power supply efficiency is improved. For this purpose, the semiconductor material may be, for example, a semiconductor material of a laser medium having a laser wavelength (fundamental wave) of 200 to 500 nm, such as diamond, gallium oxide, aluminum nitride, or GaN. In addition, a semiconductor having a band gap of 2.4 eV or more is used as the semiconductor material. For example, semiconductor materials for the laser medium, such as diamond, gallium oxide, aluminum nitride, and GaN, having a band gap of 2.4 to 6.2 eV, may be used. In addition, the longer the wavelength of laser light, the better the transmission efficiency, and the shorter the wavelength, the better the photoelectric conversion efficiency. Therefore, for long-distance transmission, a semiconductor material for the laser medium with a laser wavelength (fundamental wave) of more than 500 nm may be used. Also, if photoelectric conversion efficiency is a priority, a semiconductor material for the laser medium with a laser wavelength (fundamental wave) of less than 200 nm may be used. These semiconductor materials may be applied to either the power supply semiconductor laser 111 or the photoelectric conversion element 311. The photoelectric conversion efficiency on the power supply side or the power receiving side is improved, and the optical power supply efficiency is improved.

[0023] Next, a method for estimating the attitude of the power receiving device 310 (attitude estimation method) in the optical power supply system 1 of this embodiment will be described.

[0024] In order to estimate the posture of the power receiving device 310 in the optical power supply system 1 of this embodiment, it is necessary to operate the power supply direction switching unit 115 to switch the direction of the power supply light 112 to any angle, and to obtain information for drawing a predetermined figure with the power supply light 112 on the light receiving surface 311a of the photoelectric conversion element 311, and information regarding the figure formed by connecting the positions of the power supply light 112 detected by the light detection unit 311b of the photoelectric conversion element 311.

[0025] In this embodiment, the figure drawn by the power supply light 112 on the light receiving surface 311a of the photoelectric conversion element 311 is a cross shape in which two lines intersect at a reference point, and the two lines intersect at right angles at the reference point. The information (figure drawing data) for drawing the figure (cross shape) will be data (power supply light irradiation information) on the angle at which the power supply direction switching unit 115 switches the direction of the power supply light 112 along two directions, the horizontal and vertical directions, in order to draw the two lines that make up the cross shape. In addition, as information regarding a figure formed by connecting the positions (position information / coordinate data) of the power supply light 112 detected by the light detection unit 311b, data (light reception information) of the lengths of two lines constituting a cross shape drawn on the light receiving surface 311a detected by the light detection unit 311b is used.

[0026] In addition, when a cross-shaped reference point is drawn at the center position of the light receiving surface 311a of the photoelectric conversion element 311, the direction in which the power supply light 112 is output (the direction along the power supply light 112) is the roll axis direction, one direction perpendicular to the roll axis direction is the pitch axis direction, and the direction perpendicular to the roll axis direction and the pitch axis direction is the yaw axis direction. Also, it is assumed that a reference line L0 (see FIG. 3) is defined on the light receiving surface 311a of the photoelectric conversion element 311. For example, it is assumed that an X-axis and a Y-axis that are perpendicular to each other are defined on the light receiving surface 311a, and the reference line L0 is a line that runs along either the X-axis or the Y-axis.

[0027] Here, a mode in which a predetermined figure (a cross shape) is drawn on the light receiving surface 311a of the photoelectric conversion element 311 by the power supply light 112 will be described. In addition, an example will be described in which the angle (power supply light irradiation information) at which the power supply direction switching unit 115 switches the direction of the power supply light 112 along two directions, the horizontal and vertical directions, to draw two lines that make up a cross shape is 2α°.

[0028] 2(a), first, the power supply light 112 is applied to point (0), which is the center position of the light receiving surface 311a of the photoelectric conversion element 311. Next, the power supply direction switching unit 115 is operated to switch the direction of the power supply light 112 by an angle α along one vertical direction (upward in the figure), and the power supply light 112 is applied to point (1). Next, the power supply direction switching unit 115 is operated to switch the direction of the power supply light 112 by an angle of 2α along the other vertical direction (downward in the figure), and the power supply light 112 is directed at point (2). When the direction of the power supply light 112 is switched from point (1) to point (2), the power supply light 112 is made to pass through the center position. Next, the power supply direction switching unit 115 is operated so that the power supply light 112 is directed to the point (3). Next, the power supply direction switching unit 115 is operated to switch the direction of the power supply light 112 by an angle of 2α along one horizontal direction (leftward in the figure), and the power supply light 112 is directed at point (4). When the direction of the power supply light 112 is switched from point (3) to point (4), the power supply light 112 is made to pass through the center position. Next, the power supply direction switching unit 115 is operated to switch the direction of the power supply light 112 by an angle α along another horizontal direction (to the right in the figure), so that the power supply light 112 is directed at point (5), which is the central position.

[0029] In this way, as shown in FIG. 2(b), the direction of the power supply light 112 outputted from the power supply semiconductor laser 111 is switched by the power supply direction switching unit 115 so as to draw a first line L1 extending from point (1) to point (2) and a second line L2 extending from point (3) to point (4) on the light receiving surface 311a. In other words, the power supply direction switching unit 115 switches the direction of the power supply light 112 along the vertical direction by an angle of 2α to draw a first line L1 extending from point (1) to point (2) on the light receiving surface 311a, and the power supply direction switching unit 115 switches the direction of the power supply light 112 along the horizontal direction by an angle of 2α to draw a second line L2 extending from point (3) to point (4) on the light receiving surface 311a. In addition, if the position information when the power supply light 112 is irradiated at point (0) and the position information when the power supply light 112 is irradiated at point (5) match as coordinate data of the center position of the light receiving surface 311a, it can be determined that the position of the power receiving device 310 has not changed during the irradiation of the power supply light 112.

[0030] In addition, position information is obtained regarding the spot where the power supply light 112 hits the light receiving surface 311a detected by the light detection unit 311b of the photoelectric conversion element 311, and based on the position information, the power supply side control unit 150 can obtain received light information as information regarding a cross shape (first line L1 and second line L2), which is a figure formed by connecting the positions of the power supply light 112 detected by the light detection unit 311b. In other words, the power supply side control unit 150 is capable of executing a process of creating light receiving information regarding a cross shape (first line L1 and second line L2) formed by connecting the positions of the power supply light 112 detected by the light detection unit 311b, based on position information (coordinate data) regarding the position where the power supply light 112 hits the light receiving surface 311a detected by the light detection unit 311b. Note that instead of drawing lines on the light receiving surface 311a, dots may be drawn at points (0), (1), (2), (3), (4), and (5), and the power supply side control unit 150 may execute a process of creating light receiving information regarding a cross shape (first line L1 and second line L2) formed by connecting the positions (dots) of the power supply light 112 detected by the light detection unit 311b, based on position information (coordinate data) regarding the position where the power supply light 112 hits the light receiving surface 311a detected by the light detection unit 311b.

[0031] Then, the power supply side control unit 150, which serves as an attitude estimation control unit, executes a process of estimating the rotation angle of the power receiving device 310 (photoelectric conversion element 311) around the roll axis based on the angle between one of the two lines (first line L1, second line L2) constituting the cross shape drawn on the light receiving surface 311a detected by the light detection unit 311b and a reference line L0 on the light receiving surface 311a. For example, as shown in FIG. 3, the rotation angle of the power receiving device 310 (photoelectric conversion element 311) around the roll axis can be estimated based on the angle between a first line L1 extending from point (1) to point (2) and a reference line L0.

[0032] In addition, as shown in FIG. 4, the power supply side control unit 150 as an attitude estimation control unit estimates the rotation angle about the pitch axis and the rotation angle about the yaw axis of the power receiving device 310 (photoelectric conversion element 311) using trigonometric functions based on information (power supply light irradiation information) about the angle (here, 2α°) at which the power supply direction switching unit 115 switched the direction of the power supply light 112 along two directions, the horizontal direction and the vertical direction, to draw two lines (first line L1, second line L2) that constitute the cross shape, and information (light reception information) about the lengths of the two lines (first line L1, second line L2) that constitute the cross shape drawn on the light receiving surface 311a detected by the light detection unit 311b, and also performs a process of estimating the distance between the power supply device 110 and the center position of the light receiving surface 311b.

[0033] For example, assuming that FIG. 4(a) is a schematic diagram of a photoelectric conversion element 311 viewed from the side on which a first line L1 extending from point (1) to point (2) is drawn on the light receiving surface 311a, the length a from point (1) to the center position and the length b from the center position to point (2) correspond to the lengths of the lines constituting the cross shape drawn on the light receiving surface 311a detected by the light detection unit 311b and are therefore known values. In addition, the angle α at which the power supply direction switching unit 115 switches the direction of the power supply light 112 from point (1) to the central position, and the angle α at which the power supply direction switching unit 115 switches the direction of the power supply light 112 from the central position to point (2) are known values. Then, if the distance from power supply device 110 to the center position of light receiving surface 311b is d and the inclination of light receiving surface 311a of photoelectric conversion element 311 is θ, the following equations (1) and (2) hold according to the sine theorem of trigonometric functions. a / sinα=d / sin(π / 2-α+θ) ···(1) b / sinα=d / sin(π / 2-α-θ) ···(2)

[0034] Rearranging equations (1) and (2) gives equation (3) below. a·cos(α-θ)=b·cos(α+θ) ···(3) Furthermore, by solving for θ using the addition theorem of trigonometric functions, we obtain the following equation (4). a·(cosα·cosθ+sinα·sinθ)=b·(cosα·cosθ-sinα·sinθ) (ab)·cosα·cosθ=-(a+b)·sinα·sinθ (ab)·cosα=-(a+b)·sinα·tanθ tanθ=-[(ab)·cosα] / [(a+b)·sinα] θ=arctan{-[(ab)·cosα] / [(a+b)·sinα]} ···(4) The angle θ calculated by this equation (4) is the rotation angle θ about the pitch axis.

[0035] Moreover, by transforming equation (1) into an equal equation, we obtain the following equation (5). d=[a·sin(π / 2-α+θ)]sinα ···(5) By substituting equation (4) into equation (5), the distance d from power supply device 110 to the center position of light receiving surface 311b can be found.

[0036] Furthermore, for example, if Figure 4(a) is a schematic diagram of a photoelectric conversion element 311 viewed from the side on which a second line L2 extending from point (3) to point (4) is drawn on the light receiving surface 311a, the length a from point (3) to the center position and the length b from the center position to point (4) correspond to the lengths of the lines constituting the cross shape drawn on the light receiving surface 311a detected by the light detection unit 311b and are therefore known values. In addition, the angle α at which the power supply direction switching unit 115 switches the direction of the power supply light 112 from point (3) to the central position, and the angle α at which the power supply direction switching unit 115 switches the direction of the power supply light 112 from the central position to point (4) are known values. Among the above-mentioned equations (1) to (5) including trigonometric functions, θ calculated by equation (4) is the rotation angle θ around the yaw axis.

[0037] When the light receiving surface 311a of the photoelectric conversion element 311 is not inclined (when the inclination θ of the light receiving surface 311a is 0°), a schematic diagram of the photoelectric conversion element 311 in which a first line L1 extending from point (1) to point (2) is drawn on the light receiving surface 311a, as viewed from the side, and a schematic diagram of the photoelectric conversion element 311 in which a second line L2 extending from point (3) to point (4) is drawn on the light receiving surface 311a, as viewed from the side, are as shown in Figure 4(b).

[0038] Next, a method for estimating the attitude of the power receiving device 310 in the optical power supply system 1 of this embodiment will be described with reference to FIG.

[0039] First, the power supply semiconductor laser 111 of the power supply device 110 outputs the power supply light 112 toward the photoelectric conversion element 311 (light receiving surface 311a) of the power receiving device 310 (step S1). If the light detection unit 311b detects that the power supply light 112 is shining on the light receiving surface 311a of the photoelectric conversion element 311 (step S2; YES), the process proceeds to step S4. On the other hand, if the power supply light 112 is not incident on the light receiving surface 311a of the photoelectric conversion element 311 (step S2; NO), the power supply direction switching unit 115 is operated to adjust the irradiation direction of the power supply light 112 (step S3), and the process returns to step S2.

[0040] In step S4, the power supply direction switching unit 115 is operated to adjust the power supply light 112 to hit the center position of the light receiving surface 311a (step S4). Next, the power supply direction switching unit 115 is operated to draw a cross shape on the light receiving surface 311a with the power supply light 112 (step S5). In the first drawing, the power supply direction switching unit 115 switches the direction of the power supply light 112 along the vertical direction at an angle preset as the graphic drawing data, and draws a first line L1 from point (1) to point (2) on the light receiving surface 311a, and the power supply direction switching unit 115 switches the direction of the power supply light 112 along the horizontal direction, and draws a second line L2 from point (3) to point (4) on the light receiving surface 311a. Thereafter, when step S5 is repeated, power supply direction switching unit 115 is operated at an angle smaller than the previous angle adjusted in step S7, and the cross shape drawn becomes gradually smaller.

[0041] Next, if the light detection unit 311b detects that a cross shape (first line L1, second line L2) has been drawn on the light receiving surface 311a (step S6; YES), the process proceeds to step S8. Note that the angle (power supply light irradiation information) which is the angle when the cross shape (first line L1, second line L2) has been drawn on the light receiving surface 311a and is the operation amount of the power supply direction switching unit 115 is α(2α) shown in FIG.

[0042] On the other hand, if the light detection unit 311b detects that the cross shape (first line L1, second line L2) protrudes from the light receiving surface 311a (step S6; NO), the angle of the graphic drawing data is adjusted to be smaller so as to adjust the amount of operation of the power supply direction switching unit 115 (step S7), and the process returns to step S4. For example, in step S7, an adjustment is made to gradually decrease the operation amount of the power supply direction switching unit 115 so as to decrease the angle by 1° from the preset angle.

[0043] In step S8, information (power supply light irradiation information) on the angle (2α) at ​​which the power supply direction switching unit 115 switches the direction of the power supply light 112 along two directions, the horizontal direction and the vertical direction, in order to draw two lines (the first line L1 and the second line L2) constituting the cross shape, and information on the lengths (a, b) of the two lines (the first line L1 and the second line L2) constituting the cross shape drawn on the light receiving surface 311a detected by the light detection unit 311b Based on the received light information, etc., a process is performed to estimate the rotation angle of the power receiving device 310 (photoelectric conversion element 311) around the roll axis (see FIG. 3), the rotation angle θ of the power receiving device 310 (photoelectric conversion element 311) around the pitch axis and the rotation angle θ of the power receiving device 310 (photoelectric conversion element 311) around the yaw axis (see FIG. 4), and the distance d between the power supply device 110 and the center position of the light receiving surface 311b (see FIG. 4), thereby estimating the attitude of the power receiving device 310 (photoelectric conversion element 311) (step S8). In this manner, the process of estimating the attitude of the power receiving device 310 is completed.

[0044] As described above, in the optical power supply system 1 of this embodiment, the posture of the power receiving device 310 can be inferred based on power supply light irradiation information obtained by operating the power supply direction switching unit 115 to draw a predetermined figure with the power supply light 112 on the light receiving surface 311a of the photoelectric conversion element 311, and light reception information regarding a figure formed by connecting the positions of the power supply light 112 detected by the light detection unit 311b of the power receiving device 310. The power supply light illumination information here is the angle (2α) at ​​which the direction of the power supply light 112 is switched along two directions, the horizontal and vertical directions, and the light reception information is the lengths (a, b) of the first line L1 and the second line L2 that form the cross shape.

[0045] If the posture of the power receiving device 310 can be estimated in this manner, for example in the case of a movable power receiving device 310, the estimated posture data can be fed back to the power receiving device 310, making it possible for the power receiving device 310 to change its own posture and adjust its posture so that the power supply light 112 can easily hit the light receiving surface 311a of the photoelectric conversion element 311. In addition, the power receiving device 310 may be a mobile power receiving device equipped with a propeller and its driving source (motor), tires and their driving source (motor), etc., or the power receiving device 310 may be mounted on a moving body such as a drone, automobile, or industrial machinery (robot) and made mobile.

[0046] [Second embodiment] As shown in FIG. 6, the optical power supply system 1 of the second embodiment includes a power supply device (PSE: Power Sourcing Equipment) 110, a power receiving device (PD: Powered Device) 310, and an information management device 600. The optical power supply system 1 of the second embodiment is an embodiment in which the optical power supply system 1 of the first embodiment is provided with an information management device 600.

[0047] The information management device 600 includes a communication unit 630 and a management control unit 650. The management control unit 650 controls each unit of the information management device 600.

[0048] The communication unit 630 includes, for example, an antenna and a communication circuit, and communicates with the power supply device 110 and the power receiving device 310 via the network N to transmit and receive various data and information.

[0049] The management control unit 650 has a function of aggregating various data and information within the optical power supply system 1, and controls the information management device 600 to aggregate each device within the optical power supply system 1 (the power supply device 110, the power receiving device 310). For example, the management control unit 650 acquires power supply light irradiation information transmitted from the power supply device 110, which relates to the angle (2α) at ​​which the power supply direction switching unit 115 switches the direction of the power supply light 112 along two directions, the horizontal and vertical directions, to draw two lines (a first line L1 and a second line L2) that form a cross shape. Also, for example, the management control unit 650 acquires light receiving information transmitted from the power receiving device 310, which is information regarding the lengths (a, b) of two lines (first line L1, second line L2) that form a cross shape drawn on the light receiving surface 311a detected by the light detection unit 311b.

[0050] Then, the management control unit 650, which serves as an attitude estimation control unit, executes a process of estimating the rotation angle of the power receiving device 310 (photoelectric conversion element 311) around the roll axis based on the angle between one of the two lines (first line L1, second line L2) constituting the cross shape drawn on the light receiving surface 311a detected by the light detection unit 311b and a reference line L0 on the light receiving surface 311a (see FIG. 3). In addition, the management control unit 650, which serves as an attitude estimation control unit, estimates the rotation angle around the pitch axis and the rotation angle around the yaw axis of the power receiving device 310 (photoelectric conversion element 311) using trigonometric functions based on information (power supply light irradiation information) on the angle (2α) at ​​which the power supply direction switching unit 115 switches the direction of the power supply light 112 along two directions, the horizontal direction and the vertical direction, to draw the first line L1 and the second line L2 that form the cross shape, and information (light reception information) on the lengths (a, b) of the first line L1 and the second line L2 that form the cross shape drawn on the light receiving surface 311a detected by the light detection unit 311b, and also executes a process of estimating the distance d between the power supply device 110 and the center position of the light receiving surface 311b (see FIG. 4). In the optical power supply system 1, the method of estimating the attitude of the power receiving device 310 is the same as in the first embodiment, and therefore will not be described in detail here.

[0051] In this way, even in an optical power supply system 1 equipped with an information management device 600, the posture of the power receiving device 310 can be inferred based on power supply light irradiation information obtained by operating the power supply direction switching unit 115 to draw a predetermined figure with the power supply light 112 on the light receiving surface 311a of the photoelectric conversion element 311, and light reception information regarding a figure formed by connecting the positions of the power supply light 112 detected by the light detection unit 311b of the power receiving device 310.

[0052] Each embodiment of the present disclosure has been described above. However, the contents of the present disclosure are not limited to the above-described embodiments. Details shown in the embodiments can be appropriately modified without departing from the spirit of the invention. For example, in the above embodiment, a semiconductor laser is used as an example of the light source of the output light (power supply light) emitted by the light output device (power supply device), but the light source is not limited to this. The light source of the output light (power supply light) emitted by the light output device (power supply device) may be other light sources such as LEDs (Light Emitting Diodes) in addition to laser light sources.

[0053] An embodiment of the present disclosure is described below. (1) The posture estimation method is 1. An attitude estimation method for estimating an attitude of an optical input device in an optical transmission system in which output light is transmitted from an optical output device to an optical input device by spatial transmission, comprising the steps of: the light output device comprises a light emitting unit that outputs the output light, and a light output direction switching unit that switches the direction of the output light output by the light emitting unit to an arbitrary angle, the optical input device includes a light receiving unit having a light receiving surface that receives the output light, and a light detection unit that detects a position at which the output light hits the light receiving surface, The posture of the optical input device is inferred based on output light irradiation information that activates the light output direction switching unit to draw a predetermined figure on the light receiving surface with the output light, and received light information regarding a figure formed by connecting the positions of the output light that hit the light receiving surface detected by the light detection unit.

[0054] (2) In the posture estimation method according to (1), The figure is a cross shape in which two lines intersect at a reference point, When the direction in which the output light is output when the cross-shaped reference point is drawn at the center position of the light receiving surface is defined as the roll axis direction, the rotation angle of the optical input device around the roll axis is estimated based on the angle between one of the two lines constituting the cross shape drawn on the light receiving surface detected by the light detection unit and a reference line on the light receiving surface.

[0055] (3) In the posture estimation method according to (1), The figure is a cross shape in which two lines intersect at a reference point, When the cross-shaped reference point is drawn at the center position of the light receiving surface, a direction in which the output light is output is defined as a roll axis direction, a direction perpendicular to the roll axis direction is defined as a pitch axis direction, and a direction perpendicular to the roll axis direction and the pitch axis direction is defined as a yaw axis direction. Based on the angle at which the light output direction switching unit switches the direction of the output light along two directions, horizontal and vertical, to draw the two lines that make up the cross shape, and the lengths of the two lines that make up the cross shape drawn on the light receiving surface detected by the light detection unit, the rotation angle around the pitch axis and the rotation angle around the yaw axis of the light input device are estimated using trigonometric functions.

[0056] (4) In the posture estimation method according to (1), The figure is a cross shape in which two lines intersect at a reference point, When the cross-shaped reference point is drawn at the center position of the light receiving surface, a direction in which the output light is output is defined as a roll axis direction, a direction perpendicular to the roll axis direction is defined as a pitch axis direction, and a direction perpendicular to the roll axis direction and the pitch axis direction is defined as a yaw axis direction. estimating a rotation angle of the optical input device about a roll axis based on an angle between one of two lines constituting the cross shape drawn on the light receiving surface detected by the light detection unit and a reference line on the light receiving surface; Based on the angle at which the light output direction switching unit switches the direction of the output light along two directions, horizontal and vertical, in order to draw the two lines that make up the cross shape, and the length of the two lines that make up the cross shape drawn on the light receiving surface detected by the light detection unit, the rotation angle of the light input device about the pitch axis and the rotation angle about the yaw axis are estimated using trigonometric functions, and the distance between the light output device and the center position of the light receiving surface is also estimated.

[0057] (5) In the posture estimation method according to any one of (1) to (4), The output light is transmitted to optically power the optical input device by spatial transmission.

[0058] (6) In the posture estimation method according to any one of (1) to (4), The output light is transmitted to deliver information to the optical input device via spatial transmission.

[0059] (7) The optical transmission system is An optical transmission system for transmitting output light from an optical output device to an optical input device by spatial transmission, comprising: the light output device includes a light emitting unit that outputs the output light, a light output direction switching unit that switches the direction of the output light output by the light emitting unit to an arbitrary angle, and a light output side communication unit that receives information from the light input device, the optical input device comprises a light receiving section having a light receiving surface for receiving the output light, a light detection section for detecting a position on the light receiving surface at which the output light hits, and an optical input side communication section for transmitting information to the optical output device, The optical output device is provided with an attitude estimation control unit that estimates the attitude of the optical input device based on output light irradiation information that activates the optical output direction switching unit so as to draw a predetermined figure on the light receiving surface with the output light, and received light information regarding a figure formed by connecting the positions of the output light detected by the optical detection unit, which is information transmitted from the optical input device.

[0060] (8) In the optical transmission system according to (7), The figure is a cross shape in which two lines intersect at a reference point, When the cross-shaped reference point is drawn at the center position of the light receiving surface, the direction in which the output light is output is defined as the roll axis direction. The posture estimation control unit executes a process of estimating a rotation angle of the optical input device around a roll axis based on the angle between one of two lines constituting a cross shape drawn on the light receiving surface detected by the light detection unit and a reference line on the light receiving surface.

[0061] (9) In the optical transmission system according to (7), The figure is a cross shape in which two lines intersect at a reference point, When the cross-shaped reference point is drawn at the center position of the light receiving surface, a direction in which the output light is output is defined as a roll axis direction, a direction perpendicular to the roll axis direction is defined as a pitch axis direction, and a direction perpendicular to the roll axis direction and the pitch axis direction is defined as a yaw axis direction. The attitude estimation control unit executes a process of estimating the rotation angle about the pitch axis and the rotation angle about the yaw axis of the optical input device using trigonometric functions based on the angle at which the optical output direction switching unit switches the direction of the output light along two directions, the horizontal and vertical directions, to draw the two lines that make up the cross shape, and the lengths of the two lines that make up the cross shape drawn on the light receiving surface detected by the optical detection unit.

[0062] (10) In the optical transmission system according to (7), The figure is a cross shape in which two lines intersect at a reference point, When the cross-shaped reference point is drawn at the center position of the light receiving surface, a direction in which the output light is output is defined as a roll axis direction, a direction perpendicular to the roll axis direction is defined as a pitch axis direction, and a direction perpendicular to the roll axis direction and the pitch axis direction is defined as a yaw axis direction. The attitude estimation control unit executes a process of estimating a rotation angle of the optical input device about a roll axis based on the angle between one of two lines constituting a cross shape drawn on the light receiving surface detected by the optical detection unit and a reference line on the light receiving surface, and a process of estimating a rotation angle of the optical input device about a pitch axis and a rotation angle of the optical input device about a yaw axis using trigonometric functions based on the angle at which the optical output direction switching unit switches the direction of the output light along two directions, the horizontal and vertical directions, in order to draw the two lines constituting the cross shape and the lengths of the two lines constituting the cross shape drawn on the light receiving surface detected by the optical detection unit, and estimating a distance between the optical output device and a center position of the light receiving surface.

[0063] (11) In the optical transmission system according to any one of (7) to (10), The output light is transmitted to optically power the optical input device by spatial transmission.

[0064] (12) In the optical transmission system according to any one of (7) to (10), The output light is transmitted to deliver information to the optical input device via spatial transmission. [Explanation of symbols]

[0065] 1. Optical power supply system (optical transmission system) 110 Power supply device (optical output device) 111 Power supply semiconductor laser (light emitting part) 112 Power supply light (output light) 115 Power supply direction switching unit (optical output direction switching unit) 120 Position detection unit 130 Power supply side communication unit (optical output side communication unit) 150 Power supply control unit (attitude estimation control unit) 310 Power receiving device (optical input device) 311 Photoelectric conversion element (light receiving part) 330 Charging side communication unit (optical input side communication unit) 350 Power receiving control unit 600 Information management device 630 Communications Department 650 Management control unit (attitude estimation control unit) N Network L0 reference line L1 First line (predetermined shape (cross shape)) L2 Second line (predetermined shape (cross shape))

Claims

1. 1. An attitude estimation method for estimating an attitude of an optical input device in an optical transmission system in which output light is transmitted from an optical output device to an optical input device by spatial transmission, comprising the steps of: the light output device comprises a light emitting unit that outputs the output light, and a light output direction switching unit that switches the direction of the output light output by the light emitting unit to an arbitrary angle, the optical input device includes a light receiving unit having a light receiving surface that receives the output light, and a light detection unit that detects a position at which the output light hits the light receiving surface, an orientation of the optical input device is estimated based on output light irradiation information that has been generated by operating the optical output direction switching unit so as to draw a predetermined figure on the light receiving surface with the output light, and light receiving information regarding a figure formed by connecting positions of the output light that has hit the light receiving surface and that is detected by the light detection unit; Posture estimation method.

2. The figure is a cross shape in which two lines intersect at a reference point, a rotation angle of the optical input device around the roll axis is estimated based on an angle between one of two lines constituting the cross shape drawn on the light receiving surface detected by the light detection unit and a reference line on the light receiving surface, when a direction in which the output light is output when the reference point of the cross shape is drawn at the center position of the light receiving surface is defined as a roll axis direction; The pose estimation method of claim 1 .

3. The figure is a cross shape in which two lines intersect at a reference point, When the cross-shaped reference point is drawn at the center position of the light receiving surface, a direction in which the output light is output is defined as a roll axis direction, a direction perpendicular to the roll axis direction is defined as a pitch axis direction, and a direction perpendicular to the roll axis direction and the pitch axis direction is defined as a yaw axis direction. a rotation angle about a pitch axis and a rotation angle about a yaw axis of the optical input device are estimated using trigonometric functions based on an angle at which the optical output direction switching unit switches the direction of the output light along two directions, the horizontal direction and the vertical direction, in order to draw the two lines constituting the cross shape, and the lengths of the two lines constituting the cross shape drawn on the light receiving surface detected by the optical detection unit; The pose estimation method of claim 1 .

4. The figure is a cross shape in which two lines intersect at a reference point, When the cross-shaped reference point is drawn at the center position of the light receiving surface, a direction in which the output light is output is defined as a roll axis direction, a direction perpendicular to the roll axis direction is defined as a pitch axis direction, and a direction perpendicular to the roll axis direction and the pitch axis direction is defined as a yaw axis direction. estimating a rotation angle of the optical input device about a roll axis based on an angle between one of two lines constituting the cross shape drawn on the light receiving surface detected by the light detection unit and a reference line on the light receiving surface; estimating a rotation angle of the light input device about a pitch axis and a rotation angle of the light input device about a yaw axis using trigonometric functions based on an angle at which the light output direction switching unit switches the direction of the output light along two directions, the horizontal direction and the vertical direction, in order to draw the two lines constituting the cross shape, and the lengths of the two lines constituting the cross shape drawn on the light receiving surface detected by the light detection unit, and estimating a distance between the light output device and a center position of the light receiving surface. The pose estimation method of claim 1 .

5. The output light is transmitted to the optical input device for optical power supply by spatial transmission. A method for estimating a posture according to any one of claims 1 to 4.

6. The output light is transmitted to transmit information to the optical input device by spatial transmission. A method for estimating a posture according to any one of claims 1 to 4.

7. An optical transmission system for transmitting output light from an optical output device to an optical input device by spatial transmission, comprising: the light output device includes a light emitting unit that outputs the output light, a light output direction switching unit that switches the direction of the output light output by the light emitting unit to an arbitrary angle, and a light output side communication unit that receives information from the light input device, the optical input device comprises a light receiving section having a light receiving surface for receiving the output light, a light detection section for detecting a position on the light receiving surface at which the output light hits, and an optical input side communication section for transmitting information to the optical output device, the light output device includes an attitude estimation control unit which estimates an attitude of the light input device based on output light irradiation information which has operated the light output direction switching unit so as to draw a predetermined figure on the light receiving surface with the output light, and light reception information which is information transmitted from the light input device and relates to a figure formed by connecting positions of the output light detected by the light detection unit, Optical transmission system.

8. The figure is a cross shape in which two lines intersect at a reference point, When the cross-shaped reference point is drawn at the center position of the light receiving surface, the direction in which the output light is output is defined as the roll axis direction. the orientation estimation control unit executes a process of estimating a rotation angle of the optical input device about a roll axis based on an angle between one of two lines constituting a cross shape drawn on the light receiving surface detected by the light detection unit and a reference line on the light receiving surface.

8. The optical transmission system according to claim 7.

9. The figure is a cross shape in which two lines intersect at a reference point, When the cross-shaped reference point is drawn at the center position of the light receiving surface, a direction in which the output light is output is defined as a roll axis direction, a direction perpendicular to the roll axis direction is defined as a pitch axis direction, and a direction perpendicular to the roll axis direction and the pitch axis direction is defined as a yaw axis direction. the attitude estimation control unit executes a process of estimating a rotation angle about a pitch axis and a rotation angle about a yaw axis of the optical input device using trigonometric functions, based on an angle at which the optical output direction switching unit switches the direction of the output light along two directions, a horizontal direction and a vertical direction, in order to draw the two lines constituting the cross shape, and on lengths of the two lines constituting the cross shape drawn on the light receiving surface detected by the optical detection unit.

8. The optical transmission system according to claim 7.

10. The figure is a cross shape in which two lines intersect at a reference point, When the cross-shaped reference point is drawn at the center position of the light receiving surface, a direction in which the output light is output is defined as a roll axis direction, a direction perpendicular to the roll axis direction is defined as a pitch axis direction, and a direction perpendicular to the roll axis direction and the pitch axis direction is defined as a yaw axis direction. the attitude estimation control unit executes a process of estimating a rotation angle of the optical input device about a roll axis based on an angle between one of two lines constituting a cross shape drawn on the light receiving surface detected by the optical detection unit and a reference line on the light receiving surface, and a process of estimating a rotation angle of the optical input device about a pitch axis and a rotation angle of the optical input device about a yaw axis using trigonometric functions based on an angle at which the optical output direction switching unit switches the direction of the output light along two directions, the horizontal direction and the vertical direction, in order to draw the two lines constituting the cross shape and lengths of the two lines constituting the cross shape drawn on the light receiving surface detected by the optical detection unit, and estimating a distance between the optical output device and a center position of the light receiving surface.

8. The optical transmission system according to claim 7.

11. The output light is transmitted to the optical input device for optical power supply by spatial transmission.

11. The optical transmission system according to claim 7.

12. The output light is transmitted to transmit information to the optical input device by spatial transmission.

11. The optical transmission system according to claim 7.

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