WO2024084606A1

WO2024084606A1 - Illumination control system

Info

Publication number: WO2024084606A1
Application number: PCT/JP2022/038855
Authority: WO
Inventors: 旭洋山田; 孝介八木; 冰鄭; 遥寺島; 直紀古畑
Original assignee: 三菱電機株式会社
Priority date: 2022-10-19
Filing date: 2022-10-19
Publication date: 2024-04-25
Also published as: JP2024074970A; JP7475539B1

Abstract

An illumination control system (100) comprises an illumination device (10e) that emits image light (61) diagonally with respect to an illuminated surface (51), a storage unit (10a) that stores optical data associating the light intensity and wavelength of the image light (61) reflected by the illuminated surface (51), an identification unit (10b) that identifies characteristics of the illuminated surface (51) illuminated by the illumination device (10e), an estimation unit (10c) that estimates the position of the eyes of a user (21), and a control unit (10d) that controls the light intensity or wavelength of the image light (61) emitted from the illumination device (10e) on the basis of the characteristics of the illuminated surface (51) and the result estimated by the estimation unit (10c).

Description

Lighting Control System

This disclosure relates to a lighting control system.

In recent years, with the spread of mobile robots, it has become important to use mobile robots to alert users in spaces where mobile robots and people (users) coexist. For example, when alerting users using a lighting device mounted on a mobile robot, there is an issue that the contrast of the light emitted by the lighting device decreases due to the influence of external light. For this reason, a method has been proposed in which the brightness or contrast of an image projected onto an illuminated surface by a video projection means mounted on the robot is adjusted (see, for example, Patent Document 1).

JP 2005-313291 A (paragraph 0011, FIG. 1)

However, conventional technology does not take into account the position of the user's line of sight when the user observes the light that is projected obliquely onto the illuminated surface from the image projection means mounted on the mobile robot, making it difficult to illuminate the image in a way that enhances visibility for the user.

The purpose of this disclosure is to solve the above problems and provide a lighting control system that improves visibility for users.

A lighting control system according to an embodiment of the present disclosure includes:
A mobile robot equipped with a lighting device that illuminates an illuminated surface in an oblique direction,
an illumination device including a light source, an image light forming unit that converts light emitted from the light source into image light, and an optical element that irradiates the image light emitted from the image light forming unit onto the illuminated surface;
a memory unit in which optical data is stored that associates characteristics of the irradiated surface, a specific position, and the light intensity and wavelength of the image light reflected by the irradiated surface detected at the specific position;
An identification unit that identifies the characteristics of the illuminated surface illuminated by the lighting device;
An estimation unit that estimates a position of a user's eyes;
and a control unit that controls the light intensity or wavelength of the image light emitted from the lighting device based on the characteristic of the illuminated surface and the result estimated by the estimation unit.
A lighting control system according to another aspect of the present disclosure includes:
An illumination device that illuminates a first image light indicating a symbol, a character, or a pattern onto an illuminated surface;
A control unit is provided,
a first image formed by the first image light and background light in a state where the first image light is irradiated;
a second image formed by background light in a state where the first image light is not irradiated; and
The control unit performs image processing so that a separation area separating the first image area and the second image area is formed between a first image area corresponding to the first image light and a second image area formed around the first image area.

This disclosure provides a lighting control system that improves visibility for users.

1 is a block diagram illustrating a schematic configuration of a lighting control system according to a first embodiment. FIG. 1 is a diagram illustrating an example of the operation of a lighting control system. FIG. 2 illustrates an example of a hardware configuration of a main control unit. FIG. 13 is a diagram illustrating another example of the hardware configuration of the main control unit. FIG. 1 is a cross-sectional view illustrating a schematic configuration of a lighting device. FIG. 2 is a front view illustrating a schematic structure of an image light forming unit. 4 is a diagram showing the incident angle of incident light from a lighting device and the exit angle of exiting light. FIG. A figure showing an example of the operation of the lighting control system in embodiment 3. 10 is a flowchart illustrating an example of a method for generating mask data. FIG. 1 is a diagram showing one step of a masking process. 11A to 11C are diagrams illustrating other steps of the mask treatment. 11A to 11C are diagrams illustrating other steps of the mask treatment. 11A to 11C are diagrams illustrating other steps of the mask treatment. 11A to 11C are diagrams illustrating other steps of the mask treatment. FIG. 13 is a diagram showing an image obtained by mask processing. 13 is a flowchart showing an example of a process for controlling image light in the third embodiment. FIG. 11 is a diagram illustrating an example of a movable range map. FIG. 2 is a diagram showing an example of a floor surface map. FIG. 13 is a diagram illustrating an example of an illumination map. FIG. 13 is a diagram illustrating an example of an external light map.

<Setting coordinates>
In this embodiment, for ease of explanation, XYZ coordinates are used in the figures shown below. The +Y direction indicates the height direction, and the Z axis direction indicates the direction in which, for example, a mobile robot or a user moves. Clockwise rotation around the X axis is indicated by +RX, clockwise rotation around the Y axis is indicated by +RY, and clockwise rotation around the Z axis is indicated by +RZ.

Embodiment 1.
FIG. 1 is a block diagram illustrating a schematic configuration of a lighting control system 100 according to the first embodiment.
FIG. 2 is a diagram showing an example of the operation of the lighting control system 100.
The lighting control system 100 includes a memory unit 10a, an identification unit 10b, an estimation unit 10c, a control unit 10d, and a lighting device 10e. The lighting control system 100 is mounted on, for example, a mobile robot 11. The lighting control system 100 may further include an imaging device 41a.

<Storage unit 10a>
The storage unit 10a is, for example, a volatile memory or a non-volatile memory, and may be configured with both a volatile memory and a non-volatile memory.

In the example shown in FIG. 2, a lighting device 10e and an imaging device 41a (also referred to as a first imaging device) are mounted on the mobile robot 11, and data captured by the imaging device 41a is stored in the memory unit 10a. This creates a database in the memory unit 10a.

The storage unit 10a prestores the optical characteristics of the image light incident from various irradiated surfaces 51, which are acquired by the imaging device 41b. The imaging device 41b acquires data such as the amount of light (specifically, light intensity) and color (specifically, wavelength) of the image light reflected from the irradiated surface 51 and incident on the imaging device 41b.

Data acquired by an imaging device 41b (also called a second imaging device) different from the imaging device 41a mounted on the mobile robot 11 may be stored in the storage unit 10a. The imaging device 41b is provided, for example, at a position corresponding to the eye height of the user 21 who is positioned opposite the mobile robot 11.

<Specifying unit 10b>
The identification unit 10b identifies characteristics of the irradiated surface 51 illuminated by the lighting device 10e. For example, the identification unit 10b identifies the characteristics of the irradiated surface 51 by using an image of the irradiated surface 51 acquired by the imaging device 41a mounted on the mobile robot 11.

The identification unit 10b may identify the characteristics of the irradiated surface 51 using position information indicating the position of the irradiated surface 51, may identify the characteristics of the irradiated surface 51 using information input to the identification unit 10b from outside the lighting control system 100, or may identify the characteristics of the irradiated surface 51 using data that has been calculated based on data on multiple irradiated surfaces 51.

<Estimation unit 10c>
The estimation unit 10c estimates the position of the eyes of the user 21. The position of the eyes of the user 21 is, for example, the distance from the floor to the eyes of the user 21. The position of the eyes of the user 21 may be estimated using an image acquired by an imaging device 41a mounted on the mobile robot 11. In this case, the image acquired by the imaging device 41a is sent to the estimation unit 10c, and the estimation unit 10c estimates the position of the eyes of the user 21.

The eye position of user 21 may be estimated using an image captured by another imaging device installed indoors where user 21 is present.

The estimation unit 10c may estimate the light intensity and wavelength of the image light reflected by the irradiated surface 51 at the position of the user's 21's eyes. The estimation unit 10c may estimate the light intensity and wavelength at the position of the user's 21's eyes based on the emission angle of the image light emitted from the lighting device 10e, the height of the lighting device 10e, the light intensity of the image light, the wavelength of the image light, and the characteristics of the irradiated surface 51.

Furthermore, a distance measuring device mounted on the mobile robot 11 may be used to measure the distance from the mobile robot 11 to the user 21, and the position of the user's 21 eyes and the reflection angle of the image light reflected by the irradiated surface 51 may be estimated, thereby estimating the light intensity and wavelength at the position of the user's 21 eyes. According to this method, the light intensity and wavelength at the position of the user's 21 eyes can be estimated with high accuracy.

<Control unit 10d>
The control unit 10d controls the light intensity or wavelength of the image light 61 emitted from the illumination device 10e based on the characteristics of the illuminated surface 51 and the result estimated by the estimation unit 10c.

The control unit 10d may control the light intensity or wavelength of the image light 61 emitted from the lighting device 10e based on the data of the image light 61 and the data of the background light (external light).

When the control unit 10d detects a user (also referred to as a second user) other than the user 21 (also referred to as a first user), the control unit 10d may stop the irradiation of the image light from the lighting device 10e. For example, when it detects that another user is approaching the mobile robot 11 from a direction unrelated to the direction of the mobile robot 11 and the user 21, for example the Z-axis direction in FIG. 2, such as the ±X-axis direction, the control unit 10d may turn off the irradiation of the image light to the irradiated surface 51. This makes it possible to prevent a user other than the user 21, who is the target of the image light, from recognizing the image light. To detect the other user, an indoor imaging device may be used, or a human sensor may be installed on the mobile robot 11.

By using the identification unit 10b to identify the optical characteristics of the irradiated surface 51, even if it is detected that another user is approaching the mobile robot 11 from the ±X direction, if the estimation unit 10c can estimate that the reflected light of the image light 61 in the ±X direction is not recognizable by the other user (second user), the lighting device 10e may be kept on.

FIG. 3 is a diagram showing an example of a hardware configuration of the main control unit 42. As shown in FIG.
FIG. 4 is a diagram showing another example of the hardware configuration of the main control unit 42. In FIG.

The identification unit 10b, the estimation unit 10c, and the control unit 10d are configured, for example, by the main control unit 42. In this case, the main control unit 42 is configured, for example, by at least one processor 42a and at least one memory 42b. The storage unit 10a shown in FIG. 1 may be the memory 42b. The processor 42a is, for example, a CPU (Central Processing Unit) that executes a program stored in the memory 42b. In this case, the functions of the identification unit 10b, the estimation unit 10c, and the control unit 10d are realized by software, firmware, or a combination of software and firmware. The software and firmware can be stored as programs in the memory 42b. With this configuration, the program for realizing the functions of the main control unit 42 is executed by the computer.

Memory 42b is a computer-readable recording medium, for example, a volatile memory such as RAM (Random Access Memory) and ROM (Read Only Memory), a non-volatile memory, or a combination of volatile and non-volatile memory.

The main control unit 42 may have multiple processors 42a and multiple memories 42b. In this case, the functions of the identification unit 10b, the estimation unit 10c, and the control unit 10d are realized by these multiple processors 42a and multiple memories 42b.

The main control unit 42 may be configured with a processing circuit 42c as dedicated hardware such as a single circuit or a composite circuit. The processing circuit 42c is, for example, a system LSI. In this case, the functions of the identification unit 10b, the estimation unit 10c, and the control unit 10d are realized by the processing circuit 42c.

<Lighting device 10e>
FIG. 5 is a cross-sectional view that illustrates a schematic configuration of the lighting device 10e.
The illumination device 10e includes an illumination optical system 31b. The illumination device 10e may be, for example, a projection display device capable of displaying moving images, such as a projector. The illumination optical system 31b enables the illumination device 10e to be compact and energy-efficient.

<Illumination optical system 31b>
The illumination optical system 31 b includes a light source 1 , an image light forming section 3 , and a projection optical section 4 .

<Light source 1>
The light source 1 is a solid-state light source that emits light L1. The light source 1 is, for example, an LED (light-emitting diode). The light L1 emitted from the light-emitting surface of the light source 1 is incident on the image light forming unit 3 as diffused light. Note that the light L1 emitted from the light-emitting surface of the light source 1 may be directional light whose divergence angle in the ±RX directions is less than ±60 degrees (1/2 beam angle: 120 degrees).

The light source 1 may be, for example, a light source that emits a mixture of excited fluorescent light and laser light that has passed through a phosphor applied to a flat surface by irradiating the phosphor with an excitation laser light having a central wavelength of 448 nm.

Light source 1 may be a light source that emits only fluorescent light.

The light source 1 may be composed of only a laser diode. In this case, the size of the light-emitting surface of the light source 1 is small. Therefore, a rectangular rod lens or light pipe that increases the size of the light-emitting surface may be disposed between the light source 1 and the image light forming unit 3.

Similarly, if the area of the laser light incident on the phosphor is narrow, a rod lens or light pipe may be disposed between the light source 1 and the image light forming unit 3.

Even in the case of an LED light source, a rod lens or light pipe may be disposed between the light source 1 and the image light forming section 3 in order to form the image light shape and to uniformize the light intensity. In that case, it is preferable that the size of the exit surface of the rod lens or light pipe is larger than the image light forming areas 3a2, 3b2, and 3c2 shown in FIG. 6.

<Image light forming unit 3>
FIG. 6 is a front view showing a schematic structure of the image light forming unit 3. As shown in FIG.
The image light forming section 3 is disposed between the light source 1 and the projection optical section 4. The image light forming section 3 changes the light L1 emitted from the light source 1 into image light and emits it toward the projection optical section 4. The image light forming section 3 is rotatably supported. The image light forming section 3 rotates, for example, by a rotational driving force transmitted from a rotation drive section (for example, a motor). The image light forming section 3 rotates, for example, in the +RZ direction. The image light forming section 3 may also rotate in the -RZ direction.

In the example shown in FIG. 6, the structure of the image light forming unit 3 when viewed in the +Z axis direction is shown. The rotation center axis Ra of the image light forming unit 3 is not positioned coaxially with the optical axis C1.

As shown in FIG. 6, the image light forming unit 3 has multiple segments (segment 3a, segment 3b, and segment 3c in FIG. 6) divided in the +RZ direction. In the example shown in FIG. 6, the image light forming unit 3 is divided into three segments.

The three

segments

3a, 3b, and 3c each include an image light forming area 3a2, 3b2, and 3c2. The image light forming unit 3 can form image light that forms one type of image out of multiple types of images (three types in the example shown in FIG. 6) as it rotates.

Specifically, light L1 that passes through

segments

3a, 3b, and 3c that overlap with optical axis C1 is converted into image light 61. Image light forming unit 3 has light-shielding regions 3a1, 3b1, and 3c1, and light L1 that reaches light-shielding regions 3a1, 3b1, and 3c1 does not travel in the +Z direction.

When any of the image light forming areas 3a2, 3b2, or 3c2 faces the optical axis C1, the light L1 passes through the corresponding image light forming area 3a2, 3b2, or 3c2, travels in the +Z direction, and reaches the projection optical unit 4.

In order to make the lighting device 10e compact, it is preferable to configure the projection optical unit 4 with a small number of optical elements (projection lenses), and considering the imaging performance of the projection optical unit 4 on the illuminated surface 51, the image formed by the image light 61 is preferably a simple pattern such as letters or symbols, but the image formed by the image light 61 is not limited to letters or symbols. Note that Figure 6 shows a configuration in which the projection optical unit 4 has one optical element.

The shape of the image light forming areas 3a2, 3b2, and 3c2 may be a shape that corrects distortion (e.g., trapezoidal distortion) that occurs during oblique projection.

Each of the central angles β1, β2, and β3 shown in FIG. 6 is, for example, 120 degrees. The central angles can be changed according to the number of segments. As long as it is possible to detect the timing at which the image light forming areas 3a2, 3b2, and 3c2 pass the optical axis C1, the central angles β1, β2, and β3 may be different angles. The rotation angle steps may be determined in advance.

<Projection optical unit 4>
The projection optical unit 4 is, for example, an optical element such as a projection lens. The projection optical unit 4 irradiates the image light emitted from the image light forming unit 3 in an oblique direction onto the irradiated surface 51. The projection optical unit 4 forms, for example, a projection pattern of the image light 61 formed by the image light forming unit 3. The projection optical unit 4 has a function of forming an image of the image light 61 formed by the image light forming unit 3 on the irradiated surface 51.

The projection optical unit 4 may project a blurred projection pattern onto the illuminated surface 51. The projection optical unit 4 may be configured with a reflecting mirror or a combination of a reflecting mirror and a lens.

<Database>
The optical data, which associates the characteristics of the irradiated surface 51, a specific position, and the light intensity and wavelength of the image light reflected by the irradiated surface 51 detected at the specific position, is stored in the storage unit 10a. In this way, a database is constructed in the storage unit 10a.

In FIG. 2, when the emission conditions of the illumination device 10e onto the illuminated surface 51 (e.g., the incident angle of the image light 61, the irradiation distance, the installation height, etc.) are fixed, the light intensity and wavelength acquired by the imaging device 41a and the imaging device 41b may be stored in the memory unit 10a as optical data.

The height of the imaging device 41b in the Y-axis direction may be changed and height data acquired by the imaging device 41b may be stored in the memory unit 10a. This makes it possible to take into account the height of the user 21 and the distance between the mobile robot 11 and the user 21. In this way, the light intensity and wavelength acquired by the pair of

imaging devices

41a, 41b may be stored in the memory unit 10a.

Optical data may be created by appropriately changing conditions such as the emission conditions of the lighting device 10e onto the irradiated surface 51 (incident angle, irradiation distance, installation height, etc.) and the placement conditions of the

imaging devices

41a and 41b.

FIG. 7 is a diagram showing the incident angle αi of the incident light Li (i.e., the image light 61) from the illumination device 10e and the exit angle αo of the exit light Lo.
As shown in FIG. 7, in order to create a database taking into consideration the emission conditions (incident angle, irradiation distance, installation height, etc.) of the lighting device 10e mounted on the mobile robot 11 and the eye position of the user 21, for example, the light intensity and reflectance for wavelength for each emission angle αo (-80 degrees to 80 degrees) of the emitted light Lo relative to the incident light Li for each incident angle αi (-80 degrees to -5 degrees) may be acquired as optical data.

When acquiring the characteristics of the irradiated surface 51, the incident light Li does not necessarily have to be light from the lighting device 10e. When identifying the characteristics of the irradiated surface 51 based on data acquired by the imaging device 41a mounted on the mobile robot 11, it is desirable to acquire data on the emission angle αo (-80 degrees to 0 degrees), for example.

The characteristics of the irradiated surface 51 are, for example, reflectance, scattering degree, glossiness, or color. The material of the irradiated surface 51 may be tile or cloth. If the material of the irradiated surface 51 is known, the characteristics of the irradiated surface 51 can be easily identified by storing multiple known materials in the memory unit 10a. In other words, calculation processing based on the data acquired by the imaging device 41a is not required, and the characteristics of the irradiated surface 51 can be easily identified.

By acquiring data on a reference surface (e.g., a completely scattering white surface), it is possible to eliminate the influence of the light source color of the incident light Li (white depends on the light source, e.g., 3000K, 5000K, etc.).

The light intensity of each wavelength of the reflected light is the light intensity of each wavelength obtained by multiplying the light intensity of each wavelength of the light source 1 by the reflectance of each wavelength of the irradiated surface 51. The light obtained by multiplying the spectral distribution (light intensity of each wavelength) of the light source 1 by the reflectance of each wavelength of the irradiated surface 51 enters the eye of the user 21. Therefore, by normalizing the light intensity of each wavelength using the data of the reference surface, it is possible to calculate the relative reflectance of each wavelength of the irradiated surface 51. Here, if the reference surface has a reflectance of 100%, it is possible to calculate the absolute reflectance of each wavelength of the irradiated surface 51. In other words, by storing the data of the reference surface of the lighting device 10e in the storage unit 10a, it is possible to convert a database created with a different light source color into a database of the lighting device 10e. In other words, by normalizing the data of the reference surface of the lighting device 10e with the data of the reference surface of a different light source color, it is possible to calculate the correction coefficient of the reflectance of each wavelength.

Advantages of the First Embodiment
According to the first embodiment, the control unit 10d controls the light intensity or wavelength of the image light 61 emitted from the lighting device 10e based on the characteristics of the irradiated surface 51 and the result estimated by the estimation unit 10c. This makes it possible to provide the lighting control system 100 that improves visibility for the user.

Embodiment 2.
In the second embodiment, the data stored in the storage unit 10a and the control unit 10d are different from those in the first embodiment. The other configurations in the second embodiment are the same as those in the first embodiment.

<Database>
In addition to the data described in embodiment 1, the memory unit 10a may store information regarding the shape of the image light formed by symbols, characters, or simple patterns (including data such as mask data for each pattern).

<Mask data creation>
FIG. 8 is a diagram showing an example of the operation of lighting control system 100 in the second embodiment.
FIG. 9 is a flowchart showing an example of a method for generating mask data.
In the second embodiment, for example, mask data of the image light 61 irradiated from the lighting device 10e is generated when the lighting device 10e is started up.

In step S21, while the lighting device 10e is not emitting light, the imaging device 41a captures an image of the background light (specifically, external light) on the illuminated surface 51.

In step S22, the lighting device 10e irradiates the irradiated surface 51 with image light 61, and the imaging device 41a captures the image (an image combining background light and image light 61) projected onto the irradiated surface 51 by the lighting device 10e. That is, the imaging device 41a captures the image formed on the irradiated surface 51 by the image light 61. In this case, the image formed on the irradiated surface 51 by the image light 61 is, for example, an image showing a symbol, character, or pattern.

In step S23, the control unit 10 acquires the images acquired by the imaging device 41a (an image of the background light and an image combining the background light and the image light 61), and performs image processing such as difference calculation, binarization, and boundary extraction (e.g., mask processing).

In step S24, the mask data (image area, background area, boundary area) for each pattern is stored in the memory unit 10a. The patterns are, for example, the image light formation areas 3a2, 3b2, and 3c2 shown in FIG. 6.

An example of the mask process will be described.
10 to 15 are diagrams showing the steps of the masking process.
When the difference calculation is performed, the illumination device 10e irradiates the illuminated surface 51 with image light 61, and the imaging device 41a captures an image 61A (FIG. 10).

Next, while the illumination device 10e is not emitting image light 61, the imaging device 41a captures an image 61B formed by background light (specifically, external light) on the illuminated surface 51 (FIG. 11). As shown in FIG. 12, a difference image 61C is calculated by taking the difference between the image 61A and the image 61B.

After binarizing the difference image 61C as shown in Fig. 13, the area between the image area 61D (also referred to as the first image area) and the background area 61E (also referred to as the second image area) is extracted as shown in Fig. 14, and divided into three areas, the image area 61D, the background area 61E, and the separation area 61F (also referred to as the boundary area), as shown in Fig. 15. With the above processing, the mask processing is completed.
In addition, when masking, binarization is not essential, and weighting may be applied to the boundary region in stages. In other words, the masking method is not limited as long as the image region 61D, the background region 61E, and the separation region 61F are divided into three regions.
Although the area is divided into three regions in order to perform control with high accuracy, if the accuracy is acceptable, it is also possible to divide only the image area and the background area, i.e., to divide into two areas. This has the advantage of making control easier.

<Control unit 10d>
In the second embodiment, the control unit 10d performs mask processing using images acquired in advance (e.g., an image 61A including a pattern and an image 61B formed by background light), and controls the light intensity of the light emitted from the illumination device 10e using data obtained by the mask processing. Specifically, the control unit 10d compares the light intensity of a first image region formed by an image region 61D with the light intensity of a background region 61E that forms a second image region different from the first image region around the first image region, and controls the light intensity of the image light 61 irradiated from the illumination device 10e so that the light intensity of the image region 61D is greater than the light intensity of the background region 61E.

FIG. 16 is a flowchart showing an example of a process in the control unit 10d according to the second embodiment.
The process shown in FIG. 16 is performed, for example, while the mobile robot 11 is moving.
In step S25, the control unit 10d acquires the image formed on the illuminated surface 51.

In step S26, the control unit 10d separates the acquired image into three regions: an image region 61D, a background region 61E, and a separation region 61F, using mask data corresponding to the pattern of the image light 61. The separation region 61F is provided to avoid the effects of the imaging performance of the image region 61D and image blurring caused by vibrations of the lighting device 10e. This makes it possible to clearly separate the image region 61D and the background region 61E.

In step S27, the control unit 10d calculates the light intensity of the image area 61D and the light intensity of the background area 61E using the data of the image area 61D, the data of the background area 61E, and the data acquired by the imaging device 41a.

In step S28, the control unit 10d controls the illumination device 10e so that the light intensity of the image region 61D forming the first image region is greater than the light intensity of the background region 61E forming the second image region. For example, the control unit 10d controls the light intensity of the image light 61 irradiated from the illumination device 10e so that the relationship between the light intensity of the image region 61D and the light intensity of the background region 61E approaches a preset target value. When the target value is set to a value at which the light intensity of the image region 61D is more than twice the light intensity of the background region 61E, the control unit 10d controls the light intensity of the image light 61 so that the light intensity of the image region 61D is more than twice the light intensity of the background region 61E.

The processes from step S25 to step S28 may be repeated.

It is preferable that the area of the background region 61E is 0.5 times or more the area of the image region 61D irradiated on the irradiated surface 51. This makes it possible to narrow the calculation area and increase the calculation speed. As a result, the contrast can be increased and the image light 61 can be emphasized.

As described above, according to the second embodiment, the control unit 10d compares the light intensity of the first image area formed by the image area 61D with the light intensity of the background area 61E that forms a second image area different from the first image area around the first image area, and controls the light intensity of the image light 61 irradiated from the illumination device 10e so that the light intensity of the image area 61D is greater than the light intensity of the background area 61E.

For example, by separating the image area 61D, background area 61E, and separation area 61F into three areas and excluding separation area 61F from the calculation, it is possible to calculate the contrast ratio with high accuracy. As a result, the image light 61 can be emphasized, and the visibility of the first image for the user 21 can be improved. In addition, it is possible to suppress a decrease in the accuracy of the calculated contrast ratio due to the influence of the imaging performance of the image area 61D, image blur due to vibration of the lighting device 10e, etc.

The control unit 10d preferably controls the lighting device 10e so that the light intensity of the image area 61D forming the first image area is greater than the light intensity of the background area 61E forming the second image area. This can further increase the visibility of the first image area for the user 21.

For example, it is preferable that the control unit 10d controls the light intensity of the image light 61 so that the light intensity of the image region 61D is at least twice the light intensity of the background region 61E. This can further increase the visibility of the first image region for the user 21.

In this embodiment, in order to increase the control speed, masking is performed using images acquired in advance (e.g., image 61A including a pattern and image 61B formed by background light), but image processing may also be performed in real time.
For example, an imaging device 41a mounted on the mobile robot 11 or an imaging device installed on a ceiling or wall surface of a room where the mobile robot 11 moves may acquire a first image area when image light is irradiated, and acquire a second image area formed around the first image area when image light is not irradiated, and the control unit 10d may perform image processing so that a separation area is formed between the first image area and the second image area, separating the first image area from the second image area.
This makes it possible to calculate the contrast ratio with high accuracy.
This separation function is not limited to the configuration shown in Fig. 1. It may be applied to a system that does not include a storage unit, a characteristic unit, and an estimation unit, and may be applied to a system that does not use oblique projection. There are no particular limitations on the system to which it is applied, and it may be used to calculate a contrast ratio with high accuracy. In that case, the imaging device is not limited to the above, and it is sufficient if it can input a captured image of the target area to the system.

Embodiment 3.
In the third embodiment, the data stored in the storage unit 10a is different from that in the first embodiment. Other configurations in the third embodiment are the same as those in the first embodiment.

In the memory unit 10a, an indoor information database is constructed regarding information about the indoor area in which the mobile robot 11 moves. The indoor information database is composed of, for example, a movable range map 81, a floor surface map 82, a lighting map 83, and an external light map 84. The control unit 10d uses the indoor information database to appropriately control the image light (specifically, the light intensity and wavelength of the reflected light from the irradiated surface 51 at the position of the user's 21 eyes).

FIG. 16 is a flowchart showing an example of a process for controlling image light in the third embodiment.
<Movement range map 81>
FIG. 17 is a diagram showing an example of the movable range map 81. As shown in FIG.
The movable range map 81 is data showing the movable range of the mobile robot 11. Specifically, the movable range map 81 is data showing the movable range of the mobile robot 11, taking into consideration indoor conditions such as the indoor floor surface, obstacles, etc. The movable range map 81 is classified into a movable area 81a and an unmovable area 81b, and is composed of data showing these areas.

<Floor Map 82>
FIG. 18 is a diagram showing an example of the floor surface map 82. As shown in FIG.
The floor surface map 82 is data indicating the optical characteristics of the floor surface corresponding to the movable area 81 a or the type of material of the floor surface (i.e., the irradiated surface 51) corresponding to the movable area 81 a. Therefore, the floor surface map 82 is associated with the movable range map 81.

In the example shown in FIG. 18, data "C1" indicates a carpet (first carpet), data "C2" indicates another carpet (a second carpet different from the first carpet), and data "PT" indicates a P tile. The optical characteristics of these data "C1", "C2", and "PT" are stored in advance in the memory unit 10a. The optical characteristics of these data "C1", "C2", and "PT" are identified by the identification unit 10b, for example, based on the position information or movement path information of the mobile robot 11. The movement path information of the mobile robot 11 is, for example, information indicating a movement path set to travel through a specific location during a specific time period, and is stored in advance in the memory unit 10a. Note that the movement path information of the mobile robot 11 may also be information indicating a movement path set arbitrarily before operation.

<Lighting Map 83>
FIG. 19 is a diagram showing an example of the illumination map 83. As shown in FIG.
The illumination map 83 is data indicating the positions (e.g., the position of the ceiling) of the lighting fixtures corresponding to the movable area 81a. Therefore, the illumination map 83 is associated with the movable range map 81. For example, the illumination map 83 indicating the type of lighting fixture for each movable area 81a is stored in the storage unit 10a.

In the example shown in FIG. 19, data "FL" indicates a fluorescent lamp (daylight white), and data "DL" indicates a downlight (warm white). Data such as the type of lighting fixture and light source color, such as the data "FL" and "DL", are pre-stored in the memory unit 10a.

The light intensity at the eye position of the user 21 may be estimated using the illuminance on the floor surface, the positions of the lighting fixtures, and the characteristics of the irradiated surface 51 that are stored in advance in the memory unit 10a. This eliminates the need to estimate the effect of background light using the imaging device 41a mounted on the mobile robot 11 or the imaging device 41b installed indoors.

In the case of color, similar to light intensity, the color distribution of reflected light on the floor surface corresponding to the movable range map 81 may be stored in the storage unit 10a from multiple viewpoints. For example, the color distribution of reflected light may be stored in the storage unit 10a taking into account the eye position and line of sight of the user 21.

The chromaticity or color information of the floor surface (i.e., the irradiated surface 51) may be stored in advance in the memory unit 10a, and the color at the eye position of the user 21 may be estimated using the positions of the lighting fixtures in the illumination map 83, the light source color, and the characteristics of the irradiated surface 51.

<External Light Map 84>
FIG. 20 is a diagram showing an example of the external light map 84. As shown in FIG.
The external light map 84 is data showing the intensity distribution of reflected light in the movable area 81a where external light enters. Therefore, the external light map 84 is associated with the movable range map 81. The intensity distribution of reflected light corresponds to, for example, an estimated value of the solar altitude in the area where external light enters according to conditions such as weather information and season. The intensity distribution of reflected light may be stored in the storage unit 10a, for example, taking into consideration the position of the eyes of the user 21 and the line of sight of the user 21.

The light intensity at the eye position of the user 21 may be estimated using the illuminance on the floor surface, the incident angle of external light, and the characteristics of the irradiated surface 51 that are pre-stored in the memory unit 10a.

In the example shown in FIG. 20, the light intensity of the area indicated by data "N1" and the light intensity of the area indicated by data "N2" when external light enters the house from the upper side of FIG. 20 (e.g., the north side) are stored in advance in the storage unit 10a. The open/closed state of the blinds may also be stored in advance in the storage unit 10a. This makes it possible to estimate the effect of external light using the open/closed information of the blinds.

As described above, according to the third embodiment, the movable range map 81, the floor surface map 82, the illumination map 83, and the external light map 84 are stored in advance in the storage unit 10a. Therefore, by using these data, it is possible to identify the characteristics of the irradiated surface 51 and estimate the light intensity and wavelength at the position of the user 21's eyes based on information such as the position and movement path of the mobile robot 11. In other words, without using the imaging device 41a, for example, by estimating the position of the user 21's eyes using an image acquired by another imaging device installed indoors where the user 21 is present, it is possible to appropriately control the light intensity and wavelength of the image light (i.e., the light reflected on the irradiated surface 51 at the position of the user 21's eyes). As a result, it is possible to improve visibility for the user 21.

When the mobile robot 11 is moving through the movable area 81a of the movable range map 81, the characteristics of the background light and the irradiated surface 51 acquired by the imaging device 41a may be stored in the memory unit 10a.

The data stored in the memory unit 10a may be data generated using artificial intelligence.

The features of each of the embodiments described above can be combined with each other.

1 light source, 3 image light forming section, 4 projection optical section, 10a memory section, 10b identification section, 10c estimation section, 10d control section, 10e lighting device, 11 mobile robot, 21 user, 31b lighting optical system, 41a, 41b imaging device, 42 main control section, 42a processor, 42b memory, 51 irradiated surface, 100 lighting control system.

Claims

A mobile robot equipped with a lighting device that illuminates an illuminated surface in an oblique direction,
an illumination device including a light source, an image light forming unit that converts light emitted from the light source into image light, and an optical element that irradiates the image light emitted from the image light forming unit onto the illuminated surface;
a memory unit in which optical data is stored that associates characteristics of the irradiated surface, a specific position, and the light intensity and wavelength of the image light reflected by the irradiated surface detected at the specific position;
An identification unit that identifies the characteristics of the illuminated surface illuminated by the lighting device;
An estimation unit that estimates a position of a user's eyes;
and a control unit that controls the light intensity or wavelength of the image light emitted from the lighting device based on the characteristics of the illuminated surface and the result estimated by the estimation unit.
Further comprising an imaging device;
The lighting control system according to claim 1 , wherein the estimation unit estimates the position of the user's eyes by using an image captured by the imaging device.
The image light is a first image light indicating a symbol, a character, or a pattern, which is irradiated onto the illumination surface;
The control unit is
a first image formed by the first image light and background light in a state where the image light is irradiated;
a second image formed by the background light in a state where the image light is not irradiated;
The lighting control system according to claim 1 or 2, wherein the control unit performs image processing so that a separation area is formed between a first image area corresponding to the first image light and a second image area formed around the first image area, the separation area separating the first image area and the second image area.
The lighting control system according to claim 3, wherein the control unit controls the lighting device so that the light intensity of the image light forming the first image is greater than the light intensity of the background light forming the second image.
The lighting control system according to claim 3 or 4, wherein the control unit controls the lighting device so that the light intensity of the image light forming the first image is at least twice the light intensity of the background light forming the second image.
The lighting control system according to any one of claims 1 to 5, wherein the control unit stops illumination from the lighting device when it detects a user other than the user.
An indoor information database relating to indoor information is constructed in the storage unit,
The lighting control system according to claim 1 , wherein the control unit controls the image light by using the indoor information database.
An illumination device that irradiates a first image light indicating a symbol, a character, or a pattern onto an illumination target surface;
A control unit is provided,
a first image formed by the first image light and background light in a state where the first image light is irradiated;
a second image formed by the background light in a state where the first image light is not irradiated; and
A lighting control system in which the control unit performs image processing so that a separation area separating the first image area and the second image area is formed between a first image area corresponding to the first image light and a second image area formed around the first image area.