CN211401219U

CN211401219U - Apply to mobile robot of indoor navigation

Info

Publication number: CN211401219U
Application number: CN201922002632.2U
Authority: CN
Inventors: 赖钦伟
Original assignee: Zhuhai Amicro Semiconductor Co Ltd
Current assignee: Zhuhai Amicro Semiconductor Co Ltd
Priority date: 2019-11-19
Filing date: 2019-11-19
Publication date: 2020-09-01
Anticipated expiration: 2029-11-19

Abstract

The utility model discloses a mobile robot for indoor navigation, the organism top shell front end of this mobile robot is equipped with camera system, this camera system includes laser source transmitter and camera module, this camera module includes optical lens and the image sensor according to conventional camera fixed connection in proper order, this camera module still includes the light filter, image sensor's predetermined photosensitive area coats and is stamped the light filter, optical lens is just to the light filter with predetermined working distance, the light filter is used for focusing on the light signal of reflection in the effective detection area before image sensor's predetermined photosensitive area, the visible light in the light signal of filtration reflection; the system comprises a mobile robot, a camera module, a laser source emitter, a camera module and a camera module, wherein a laser source signal emitted by the laser source emitter is intersected with the visual angle of the camera module to form an effective detection area positioned in front of and below the mobile robot; and the image sensor is not covered with a light sensitive area of the optical filter and is used for acquiring an indoor environment image in front of the mobile robot so as to perform positioning navigation.

Description

Apply to mobile robot of indoor navigation

Technical Field

The utility model relates to a technical field of laser visual detection barrier especially relates to an apply to mobile robot of indoor navigation.

Background

The positioning navigation technology based on a single camera has the characteristics of simple structure, high reliability and convenience in production, and is increasingly applied. However, this technique has a disadvantage that the depth information of the front object is highly complex to recover, the prior art must rely on the image feature library to perform feature comparison to identify the obstacle, and the accuracy of the obstacle location identification is limited by various scenes.

Chinese patent 201420865149.1 discloses a novel obstacle recognition device, which comprises a laser source and a light curtain modulation device, and is used for emitting a light curtain parallel to the ground to identify an obstacle, and is also provided with a camera matched with the emitting direction of the light curtain emitting device and used for shooting the reflected light spot of the obstacle, when a horizontal light curtain irradiates the obstacle in the advancing direction, a bright strip-shaped light spot is formed on the obstacle, a scene picture containing the reflected light spot is shot by the camera, then the distribution condition of the obstacle on the advancing path can be judged by a light spot detection device according to the light spot distribution condition on the picture, the technology for detecting the obstacle according to the light spot does not need to rely on an image feature library to carry out feature comparison to recognize the obstacle, however, in the process of detecting the obstacle by the obstacle recognition device in the working environment, the parallel light curtain emitted by the light curtain modulation device is reflected by the wall area of the indoor environment, or other visible light with strong reflectivity exists, so that the reflected light spot image shot by the camera does not necessarily represent the obstacle existing in the front, and is possibly a misjudgment result caused by ambient light, thereby increasing the difficulty of identifying the obstacle through the light spot, and further influencing the accuracy of robot navigation.

SUMMERY OF THE UTILITY MODEL

Aiming at the technical problems, the technical scheme adds the infrared filter at the lower part of the camera sensor, filters out visible light, greatly reduces the influence caused by the environment and increases the reliability of the system. The specific technical scheme is as follows:

a mobile robot applied to indoor navigation is provided, wherein a camera system is assembled at the front end of a top shell of a machine body of the mobile robot and comprises a laser source emitter and a camera module, the camera module comprises an optical lens and an image sensor which are sequentially and fixedly connected according to a conventional camera, the camera module further comprises an optical filter, an optical filter covers a preset photosensitive area of the image sensor, the optical lens is opposite to the optical filter by a preset working distance, and the optical filter is used for focusing an optical signal reflected in an effective detection area in front of the preset photosensitive area of the image sensor and filtering visible light in the reflected optical signal; the system comprises a mobile robot, a camera module, a laser source emitter, a camera module and a camera module, wherein a laser source signal emitted by the laser source emitter is intersected with the visual angle of the camera module to form an effective detection area positioned in front of and below the mobile robot; and a photosensitive area which is not covered by the optical filter on the image sensor is used for acquiring an indoor environment image in front of the mobile robot so as to perform positioning navigation. Compared with the prior art, the laser light source transmitter cooperates the light filter of camera module to detect closely the barrier, utilizes the facula that invisible light reflection formed to go to discernment effective detection area intra-area barrier, reduces the facula image detection barrier's that the camera passes through to shoot the degree of difficulty, utilizes the regional image information of gathering that is not covered by the light filter of camera module to carry out conventional visual navigation simultaneously. Therefore, the technical scheme can not only avoid the misjudgment of the image sensor on the imaging plane due to the interference of visible light, but also keep executing the normal navigation and positioning functions.

Furthermore, the laser light source emitter is installed above the camera module, the emitting direction of the laser light source emitter is obliquely arranged downwards relative to the horizontal plane, and the emitting direction of the laser light source emitter and the optical axis of the optical lens of the camera module form a preset acute angle, so that the laser light source signal emitted by the laser light source emitter is in the range of the preset distance in front of the camera system and is intersected with the visual angle of the optical lens of the camera module to form the effective detection area. In the technical scheme, a laser light source signal emitted by the laser light source emitter is reflected by the obstacle in the effective detection area and enters the effective detection visual angle range of the camera module, so that the area for detecting the obstacle is limited in an area close to the camera system, and the influence of reflected light of a distant indoor obstacle is eliminated; and the detection of obstacles with raised ground plane is also facilitated.

Further, the optical axis of the optical lens is set to be 20 degrees upward horizontally, the range of the viewing angle of the camera module is set to be 80 degrees to 120 degrees, and the preset acute angle is set to be 40 degrees to 50 degrees. The camera module is beneficial to covering and crossing the effective detection visual angle of the camera module, so that an effective detection area is formed by crossing.

Further, the laser light source emitter comprises a left laser light source emitter and a right laser light source emitter which are symmetrically arranged on the left side and the right side of the camera module, a laser light source signal emitted by the left laser light source emitter, a laser light source signal emitted by the right laser light source emitter and the visual angle of the camera module are intersected to form an effective detection area located on the front lower side of the mobile robot, and the left laser light source emitter and the right laser light source emitter provided by the technical scheme are in a left-right opposite-emitting structure, so that the coverage area of the laser light source signal emitted by the laser light source emitter is increased, and the effective detection area is enlarged.

Further, at the position of the fixing position of the photosensitive surface built in the image sensor, the preset photosensitive area is an area covering a quarter of the surface area of the photosensitive surface from the lower edge of the photosensitive surface to the upper edge of the photosensitive surface. And the imaging of the incident light signal in the preset photosensitive area is facilitated.

Furthermore, a preset distance value exists between the installation position of the laser light source emitter and the installation position of the camera, so that the barrier reflection light spots at different distances are distributed at different positions of an imaging picture of the camera; on the premise of keeping the preset acute angle and the optical axis of the optical lens unchanged, the larger the preset distance value is set, the larger the effective detection area is. According to the technical scheme, the relative distance between the laser light source emitter and the camera module can be adjusted according to the distribution condition of the indoor environment, so that the optical filter can effectively filter visible light, more infrared laser signals from the laser light source emitter are incident, and the detection effect of the barrier is further improved.

Furthermore, the optical filter is attached to the preset photosensitive area by a preset material, and the area of the optical filter is equal to that of the preset photosensitive area. The optical filter fixing structure is simple, the structure of the camera module is simplified, the cost is saved, the incident infrared laser signal can be guided to be in the infrared imaging in the preset photosensitive area, and the visible light is filtered to be in the imaging in the preset photosensitive area.

Further, the laser light source emitter is an infrared laser emitting tube, and a laser light source signal emitted by the laser light source emitter is represented by a straight line of infrared laser, and the wavelength of the infrared laser is 800nm to 920nm, or is a combination of one or a preset number of infrared light sources within the wavelength range. According to the technical scheme, the infrared laser light source is adopted, the characteristics of high directivity and low scattering of infrared laser are fully utilized, the divergence angle of irradiated laser is extremely small, almost no scattered light exists, and meanwhile, the interference of visible light is weakened.

Further, the optical filter is an infrared band-pass filter or an infrared low-pass filter, and is used for filtering the infrared laser and finishing infrared light spot imaging in the preset photosensitive area; the optical filter is an infrared optical filter for inhibiting or filtering visible light, or a coating film adhered to the photosensitive surface of the image sensor. According to the technical scheme, the infrared light is adopted to identify the barrier, so that the purpose of reducing interference caused by the ambient light is achieved.

Drawings

Fig. 1 is a schematic diagram of a mobile robot for indoor navigation and an effective detection area formed by the mobile robot provided by the embodiment of the present invention (the laser source emitter is installed above the camera module, and the emitting direction of the laser source emitter is set obliquely downward relative to the horizontal plane).

Fig. 2 is a schematic view of light spot images displayed on the photosensitive surface corresponding to the camera module by two obstacles with different heights according to an embodiment of the present invention.

Fig. 3 is a schematic view of a mobile robot for indoor navigation and an effective detection area formed by the mobile robot according to an embodiment of the present invention (the laser light source emitter is installed on the left and right sides of the housing of the mobile robot).

Fig. 4 is a schematic view of a top view of a mobile robot for indoor navigation and an effective detection area formed by the top view (the laser light source emitter is installed on the left and right sides of the camera module, and is in a left and right correlation assembly state).

Fig. 5 is an internal assembly schematic diagram of a camera module according to an embodiment of the present invention.

Reference numerals:

101: a body of the mobile robot; 102: a drive wheel; 103: a camera module; 104: laser light source transmitter, 1041: right laser light source emitter, 1042: a left laser light source emitter; 105: a laser light source; 106: the angle of view of the camera module 103; 107: an effective detection area.

201: a light spot image with the center A and the height h; 202:201 on the image sensing chip; 203: spot images with center a1 height h 1; 204: 203.

1031: a light-sensing surface of the image sensor; 1032: an optical filter; 1033. an optical lens.

Detailed Description

The technical solution in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings in the embodiments of the present invention. To further illustrate the embodiments, the present invention provides the accompanying drawings. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the embodiments. With these references, one of ordinary skill in the art will appreciate other possible embodiments and advantages of the present invention. Elements in the figures are not drawn to scale and like reference numerals are generally used to indicate like elements.

The embodiment of the utility model provides a mobile robot for indoor navigation, as shown in fig. 1 and fig. 3, the front end of the housing of the body 101 of the mobile robot is equipped with a camera system with a laser source, the bottom of the body 101 of the mobile robot is equipped with a driving wheel 102, the camera system comprises a laser source emitter and a camera module 103, the camera module 103 comprises an optical lens and an image sensor which are connected in sequence according to a conventional camera, the camera module 103 further comprises a light filter, the embodiment covers the light filter on the preset photosensitive area of the photosensitive surface of the image sensor, in the preferred application, the light filter can be attached on the preset photosensitive area of the photosensitive surface of the image sensor through special materials, thereby fixing the light filter inside the camera module 103, compared with the prior art, the light filter and the photosensitive surface of the image sensor are kept at a certain distance through the support, the design of this embodiment reduces the design degree of difficulty of camera module, improves the imaging performance of camera module and reduces the transmissivity of visible light, also adapts to the technical trend of ultra-thin camera system of mobile robot. The emitting end of the laser light source emitter and the optical lens of the camera module 103 are both set to face the advancing direction of the mobile robot, the laser light source 105 emitted by the laser light source emitter intersects with the visual angle 106 of the camera module 103 within a preset distance range in front of the mobile robot to form an effective detection area, and the effective detection area 107 is located in the front lower portion of the mobile robot. The optical lens is opposite to the optical filter by a preset working distance, and is fixedly arranged on one side of a preset photosensitive area far away from the image sensor through a conventional lens seat in the camera module 103 and used for focusing an optical signal reflected in the effective detection area 107 on the preset photosensitive area of the image sensor; the optical filter is used for filtering visible light in the reflected optical signal before the laser light source 105 signal is focused on the light-sensitive surface, so that a preset light-sensitive area of the light-sensitive surface only receives the infrared spectrum emitted by the laser light source emitter 104, while a light-sensitive area on the image sensor, which is not covered by the optical filter, is continuously used for collecting an indoor environment image in front of the mobile robot, and a map is synchronously constructed according to the image collected in real time, so that the visual positioning navigation function is continuously executed. Compared with the prior art, the laser light source emitter is matched with the optical filter of the camera module to detect the obstacles in a close range, the light spots formed by reflection of invisible light are used for identifying the obstacles in the effective detection area, misjudgment of the image sensor in an imaging plane due to interference of visible light is avoided, and meanwhile, the image information is collected in the area, which is not covered by the optical filter, of the camera module to carry out conventional visual navigation. Therefore, the mobile robot provided by the embodiment can not only avoid misjudgment of the image sensor on the imaging plane due to visible light interference, but also keep executing a normal navigation positioning function. The difficulty of the camera in detecting the obstacle through the shot light spot image is further reduced, and meanwhile, the operation resources matched with the image library are also reduced.

As an embodiment, as shown in fig. 1, the laser light source emitter 104 is installed above the camera module 103, and the emitting direction of the laser light source emitter 104 is set obliquely downward with respect to a horizontal plane, the optical axis L of the optical lens of the camera module 103 is set obliquely upward with respect to the horizontal plane, the emitting direction of the laser light source emitter 104 and the optical axis L of the optical lens of the camera module 103 form a preset acute angle, so that the laser light source 105 emitted from the laser light source emitter 104 intersects with the viewing angle 106 of the camera module 103 to form an effective detection area 107, the laser light source 105 covers and intersects with the effective detection viewing angle range of the camera module 103 from top to bottom, and then the visible light is removed by using the optical filter installed inside the camera module 103, so as to limit the area for detecting obstacles in the area close to the front and the bottom of the mobile robot, the influence of reflected light of an indoor obstacle at a long distance is eliminated to assist in detecting an obstacle raised in the effective detection area 107.

Specifically, the emitting direction of the laser light source emitter 104 and the optical axis L of the optical lens of the camera module 103 form a preset acute angle between 40 degrees and 50 degrees, the emitting end of the laser light source emitter 104 and the optical lens of the camera module 103 both face the front of the camera system, the obstacle protruding on the front ground plane of the camera system is detected in an auxiliary manner, and a preset emergent angle is formed between the emitting direction of the laser light source emitter 104 and the horizontal direction, so that the laser light source 105 emitted by the laser light source emitter 104 intersects with the visual angle of the camera module 103 within a preset distance range in front of the camera system to form an effective detection area 107. In this embodiment, the installation mode of the camera module 103 limits the region for detecting the obstacle to the region near the camera system, that is, the effective detection region 107, and after the optical filter of the camera module 103 eliminates visible light, interference of reflected light of a distant indoor obstacle or external strong visible light reflection can be eliminated, false obstacles caused by strong light spots are eliminated, and the camera module is suitable for various indoor complex environments. It is noted that the predetermined exit angle ranges from 40 degrees to 80 degrees. The emitting direction of the laser light source emitter relative to the horizontal plane is accurately limited, and the effective detection visual angle range of the camera can be covered and crossed.

As an embodiment, as can be seen from fig. 3 and 4, the laser source transmitter 104 includes a left laser source transmitter 1042 and a right laser source transmitter 1041, which are symmetrically or asymmetrically installed on the left and right sides of the camera module 103 as shown in fig. 4, and are correspondingly installed on the left and right side housings of the body 101 of the mobile robot, and both keep a certain distance from the camera module 103. The laser light source signal 105 emitted from the left laser light source emitter 1042, the laser light source signal 105 emitted from the right laser light source emitter 1041, and the view angle 106 of the camera module 103 intersect to form an effective detection area 107 located in the front lower part of the mobile robot, and compared with the structure in which the laser light source emitter 104 is installed above the camera module 103 provided in the foregoing embodiment, the left-right opposite-emitting structure of the left laser light source emitter 1042 and the right laser light source emitter 1041 provided in this embodiment increases the coverage area of the laser light source signal emitted from the laser light source emitter 104, and expands the effective detection area.

Specifically, the laser light source emitter 1042 and the right laser light source emitter 1041 are both preferably single line laser radars, and the laser light source signals 105 emitted by the laser light source emitters are all single lines and used for scanning a plane, so that the mobile robot can be helped to avoid obstacles, and the mobile robot is high in scanning speed, high in resolution and high in reliability. In this embodiment, the laser light source emitters 1042 and the right laser light source emitter 1041 are arranged on the left and right sides of the camera module 103 according to a certain shape, and their emitting directions are intersected with the optical axis of the optical lens of the camera module 103, and form a certain angle with each other, so as to greatly enhance the linear concentration degree of the laser light source 105.

The preferred embodiment can also be provided with a preset number of left laser light source emitters and right laser light source emitters which are correspondingly arranged on the left side and the right side of the camera module 103 to be arranged in a regular shape, so that light spots formed by the laser light source emitters on the reflecting surface of the obstacle have a certain shape, and the light spots form a graph which is easy to identify in the imaging plane of the camera module 103, thereby being beneficial to identifying the obstacle through the light spots; the laser emitted by the laser light source emitters can form a plurality of light spots on the obstacle, and the light spots are particularly used for forming a pattern which can be conveniently identified, so that the interference caused by bright spots formed by the obstacle by external light (such as strong light) is further reduced. And is also beneficial to detect the raised obstacles around the ground plane in front of the camera system from multiple directions, as shown in fig. 4, the obstacle on the right side of the advancing direction of the body 101 of the mobile robot is detected by the light spot formed by the left laser source emitter 1042, and the obstacle on the left side of the advancing direction of the body 101 of the mobile robot is detected by the light spot formed by the right laser source emitter 1041.

On the basis of the foregoing embodiment, at the current fixed position of the photosensitive surface 301 built in the image sensor, the preset photosensitive region is a region covering a quarter of the surface of the photosensitive surface 301 in a direction from the lower edge of the photosensitive surface 301 to the upper edge thereof, such as a region covered by black oblique lines in fig. 5, and in combination with the preset acute angle between the emitting direction of the laser source emitter 104 and the optical axis L of the optical lens of the camera module 103 in the foregoing embodiment, the preset acute angle is between 40 degrees and 50 degrees, which is favorable for guiding the incident light signal to form an image in the preset photosensitive region. The photosensitive surface 301 is formed by regularly arranging a plurality of three-primary-color (R, G, B) photosensitive components according to a specific sequence, and in this embodiment, the photosensitive components in the preset photosensitive area are set to be covered by the infrared light imaging area and used for outputting infrared light imaging data.

The laser light source emitter is preferably an infrared laser emitting tube, a laser light source signal emitted by the laser light source emitter is represented by a straight line of infrared laser, the wavelength of the infrared laser is 800nm to 920nm, or the combination of one or a preset number of wavelengths in the wavelength range is adopted, the infrared laser is a near-infrared light source, the infrared laser is invisible light, human eyes can sense infrared sensing weakly or even cannot sense infrared sensing, the infrared laser does not disturb people, the infrared laser is applied to the process of human imperceptibility, and the camera system can utilize the infrared laser to avoid obstacles in the dark. The embodiment adopts the infrared laser light source, fully utilizes the characteristics of high directivity and low scattering of the infrared laser, ensures that the divergence angle of the irradiated laser is extremely small, almost no scattered light exists, and simultaneously weakens the interference of visible light. As shown in the laser light source 105 of fig. 1, the laser light source always intersects with the ground, and the light spot reflected by the ground can only be shot by the camera module 103 when entering the effective detection area 107. When the laser light source 105 irradiates an object, a bright strip-shaped light spot is projected on the object. As shown in fig. 1, when the laser light source 105 intersects with the road surface and irradiates downward at the preset exit angle, if there is an obstacle on the road surface, a bright light spot is reflected on the surface of the obstacle, and enters the effective detection area 107 to be captured by the camera module 103.

Therefore, the optical filter is preferably an infrared band-pass filter or an infrared low-pass filter, and is used for suppressing or filtering visible light and spectral signals in a high frequency band, and only allowing infrared light signals to pass through, in a specific application, the optical filter is a low-pass type, a band-pass type, a long-pass cut-off type or a cut-off type infrared filter, for example, when the laser source transmitter emits 850nm infrared laser to perform obstacle identification, an infrared band-pass filter with a central wavelength of 850nm may be used in cooperation, so that 850nm infrared reflected laser passes through, and reflected light with other wavelengths is filtered. The infrared band-pass filter or the infrared low-pass filter adopted in this embodiment may be an infrared filter that suppresses or filters visible light, or a coating that is attached to the photosensitive surface of the image sensor, and they are used to filter out the infrared laser, thereby blocking visible light from entering the photosensitive surface 301 of the image sensor, so that the light spot imaging of the photosensitive surface 301 in the preset photosensitive area may not be interfered by visible light, and the infrared light imaging quality is improved, thereby realizing that the image sensor receives the infrared laser, and the infrared light spot imaging is completed in the preset photosensitive area. This embodiment is in predetermine photosensitive area configuration in the camera system behind the light filter, adopt infrared light discernment barrier, reduce the interference that ambient light brought, simultaneously the camera system can also utilize visible light to carry out the vision navigation location, will keep away barrier function and synchronous positioning function by the different photosensitive area distributions of the image sensor of camera system undertake, accelerate the processing speed of mobile robot also increases the reliability of camera system.

As shown in fig. 5, the optical filter 1032 is attached to the preset photosensitive region by a preset material, and the area of the optical filter 1032 is equal to the area of the preset photosensitive region, and is configured to filter out the infrared laser in the optical signal incident to the optical lens 1033 in a manner of absorbing or reflecting the visible light, so that the infrared laser is incident to the photosensitive surface 1031 of the image sensor, as shown in the dotted line with an arrow in fig. 5, the dotted line with an arrow on the right side of the optical lens 1033 represents the optical signal incident from the outside of the camera module, and the optical signal first enters the optical lens 1033, then is refracted to become the dotted line with an arrow on the left side of the optical lens 1033, and enters the preset photosensitive region of the photosensitive surface 1031 of the image sensor, that is, enters the corresponding optical filter 1032 of fig. 5 to filter out the visible light.

In fig. 5, the optical filter may be adhered to a preset photosensitive area of the photosensitive surface 1031 of the image sensor by a special glue, so as to fix the optical filter 1032 inside the camera module 103, wherein the image sensor may be fixed to the bracket in any feasible manner in a specific application, and then fixed to the circuit board by the bracket, so as to allow the optical lens 1033 to be disposed over against the photosensitive surface of the image sensor, for example, the optical lens is fixed to the bracket by means of fastening by a snap fastener, adhering by a glue, or fastening by a threaded fastener. The optical lens 1033 faces the optical filter 1032 with a preset working distance. Similarly, the optical lens 1031 passes through the lens holder inside the camera module 103 is fixed on the side of the preset photosensitive area far away from the image sensor for focusing the optical signal reflected in the effective detection area 107 on the optical filter 1032 attached to the photosensitive surface 1031, wherein the optical lens 1033 is specifically fixed on the conventional lens holder through the snap-fit, the glue or the fastening of the threaded fastener. In this embodiment, the optical filter 1032 is configured to filter visible light in the reflected optical signal before the laser source signal is focused on the light-sensing surface 1031, so that a preset light-sensing area of the light-sensing surface 1031 only receives the infrared spectrum emitted by the laser source emitter 104. In this embodiment, the fixing structure of the optical filter 1032 on the image sensor is set to be relatively simple, which is beneficial to guiding the incident infrared laser signal to perform infrared imaging in the preset photosensitive area and filtering out visible light.

Preferably, a preset distance value exists between the installation position of the laser light source emitter 104 and the installation position of the camera module 103, so that the distances of infrared light spots reflected by obstacles at different distances from the optical center of the optical lens are different, the positions of imaging pictures distributed on the camera module 103 are also different, and the position of the optical axis of the lens of the camera module 103 is fixed. On the premise of keeping the preset acute angle and the optical axis of the optical lens 1033 unchanged, when the preset distance value is set to be larger, the larger the area of the angle of view 106 covered and intersected by the laser light source 105 is, the larger the effective detection area 107 is formed. According to the embodiment, the relative distance between the laser light source emitter and the camera module can be adjusted according to the distribution condition of the indoor environment, so that the optical filter can effectively filter visible light, more infrared laser signals from the laser light source emitter are emitted, and the detection effect of the barrier is improved.

As can be seen from fig. 1 and fig. 2, the camera module 103 captures an obstacle reflected light spot at a first preset position in the effective detection area 107, and forms a light spot image 201 on the image sensor sheet 202 at an imaging picture position of the camera module 103, where a height of a center position a of the light spot image 201 on the image sensor sheet 202 is h; when the obstacle is close to the first preset position, the distance between the obstacle and the camera module 103 is short, the camera module 103 shoots the obstacle reflection light spot at the second preset position in the effective detection area 107, and forms a light spot image 203 on the image sensing sheet 204 at the position of the imaging picture of the camera module 103, the height of the central position a1 of the light spot image 203 on the image sensing sheet 204 is h1, wherein the height h1 is obviously greater than the height h, and the horizontal distance between the first preset position and the camera module 103 is greater than the horizontal distance between the second preset position and the camera module 103. Therefore, the present embodiment can determine the distance between the image of the infrared spot reflected by the imaging frame of the camera module 103 and the obstacle in the effective detection area 107. It should be noted that after the camera system recognizes the obstacle, the distance of the obstacle can be estimated according to the height difference of the light spots distributed in the imaging picture of the camera module 103, which is based on the convex lens imaging principle in the geometric optics of the middle school textbook. Similarly, the light spot image with the rule shown in fig. 2 may appear in the embodiment corresponding to fig. 3, but the light spot image rotates 90 degrees relatively, but the embodiment corresponding to fig. 3 may still determine the distance between the reflected infrared light spot image on the imaging picture of the camera module 103 and the obstacle in the effective detection area 107 according to the reflected infrared light spot image.

As can be seen from fig. 1, 2 and 3, when a front obstacle is outside the effective detection area 107 during the moving process of the mobile robot, there is no light spot image reflected by the front obstacle on the imaging plane of the camera module 103, and the imaging plane of the camera module 103 may be regarded as the light sensing surface 1031 of the image sensor in this embodiment; in the moving robot process of marcing forward, the barrier that is in the place ahead is than far away, laser source 105 with camera module 103 visual angle does not have the intersection, camera module 103 can not shoot laser source, and there is the barrier to be close to gradually at the current face, begins to get into laser source 105 with when the intersection point region of camera module 103's visual angle 106, the barrier in the place ahead appears in effective detection area 107, and the infrared facula image that comes from the barrier reflection in the place ahead appears on image sensor's the sensitization face 1031, and in effective detection area 107, the barrier in the place ahead is closer to moving robot, the facula image is in the position deviation on image sensor's the sensitization face 1031 the distance of optical lens's optical center is the bigger. Therefore, the mobile robot can determine the distance between the mobile robot and the obstacle in the effective detection area 107 according to the reflected light spot image on the imaging picture of the camera module 103, and further make a corresponding obstacle avoidance path plan. According to the distribution condition of the indoor environment, the relative distance between the laser light source emitter 104 and the camera module 103 is adjusted on the body 101 of the mobile robot, so that the detection effect of the obstacles is improved as much as possible.

The above embodiments are only for illustrating the technical conception and the features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and to implement the present invention, which cannot limit the protection scope of the present invention. All changes and modifications that come within the spirit of the invention are desired to be protected.

Claims

1. A mobile robot applied to indoor navigation is provided, wherein a camera system is assembled at the front end of a top shell of a machine body of the mobile robot, the camera system comprises a laser source emitter and a camera module, the camera module comprises an optical lens and an image sensor which are sequentially and fixedly connected according to a conventional camera, and the mobile robot is characterized in that the camera module further comprises an optical filter, the preset photosensitive area of the image sensor is covered with the optical filter, the optical lens is opposite to the optical filter by a preset working distance, and the optical filter is used for filtering visible light in reflected optical signals before focusing the optical signals reflected in an effective detection area to the preset photosensitive area of the image sensor;

the system comprises a mobile robot, a camera module, a laser source emitter, a camera module and a camera module, wherein a laser source signal emitted by the laser source emitter is intersected with the visual angle of the camera module to form an effective detection area positioned in front of and below the mobile robot;

the image sensor also has a photosensitive area which is not covered by the filter.

2. The mobile robot of claim 1, wherein the laser source emitter is installed above the camera module, an emitting direction of the laser source emitter is inclined downward with respect to a horizontal plane, and the emitting direction of the laser source emitter and an optical axis of an optical lens of the camera module form a predetermined acute angle, so that a laser source signal emitted by the laser source emitter intersects with a viewing angle of the optical lens of the camera module within a predetermined distance range in front of the camera system to form the effective detection area.

3. The mobile robot of claim 2, wherein the optical axis of the optical lens is set to 20 degrees upward horizontally, the range of the viewing angle of the camera module is set to 80 degrees to 120 degrees, and the preset acute angle is set to between 40 degrees and 50 degrees.

4. The mobile robot of claim 2, wherein the laser light source emitter comprises a left laser light source emitter and a right laser light source emitter respectively mounted on the left and right sides of the camera module, and a laser light source signal emitted from the left laser light source emitter and a laser light source signal emitted from the right laser light source emitter intersect with the viewing angle of the camera module to form an effective detection area located in the front and below of the mobile robot.

5. The mobile robot as claimed in any one of claims 2 to 4, wherein there is a preset distance value between the installation position of the laser light source emitter and the installation position of the camera, so that the distances of the reflected light spots of the obstacles at different distances from the optical center of the optical lens are different;

on the premise of keeping the preset acute angle and the optical axis of the optical lens unchanged, the larger the preset distance value is set, the larger the effective detection area is.

6. The mobile robot according to claim 5, wherein the predetermined photosensitive area is an area covering a quarter of the surface area of the photosensitive surface in a direction from a lower edge of the photosensitive surface toward an upper edge thereof at a photosensitive surface fixing position built in the image sensor.

7. The mobile robot of claim 6, wherein the optical filter is attached to the predetermined photosensitive area with a predetermined material, and an area of the optical filter is equal to an area of the predetermined photosensitive area.

8. The mobile robot of claim 5, wherein the laser source transmitter is an infrared laser transmitter tube, and the laser source signal is represented by a straight line of near-infrared laser with a wavelength of 800nm to 920nm, or a combination of one or a predetermined number of infrared sources with a wavelength in the wavelength range.

9. The mobile robot of claim 8, wherein the optical filter is an infrared band-pass filter or an infrared low-pass filter, and is configured to filter out the infrared laser and complete infrared spot imaging in the preset photosensitive area;

the optical filter is an infrared optical filter for inhibiting or filtering visible light, or a coating film adhered to the photosensitive surface of the image sensor.