CN109784232A - A kind of vision SLAM winding detection method and device merging depth information - Google Patents

A kind of vision SLAM winding detection method and device merging depth information Download PDF

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CN109784232A
CN109784232A CN201811632974.6A CN201811632974A CN109784232A CN 109784232 A CN109784232 A CN 109784232A CN 201811632974 A CN201811632974 A CN 201811632974A CN 109784232 A CN109784232 A CN 109784232A
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key frame
map
winding detection
depth information
depth
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吴俊君
陈世浪
周林
邝辉宇
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Foshan University
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Foshan University
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Abstract

The present invention relates to robot simultaneous localization and mapping technical fields, more particularly to a kind of vision SLAM winding detection method and device for merging depth information, obtain the video streaming image shot in robot kinematics, and the key frame in video streaming image is extracted offline, the depth map of key frame is obtained with deep neural network training, the global characteristics descriptor of depth map is extracted using M2DP algorithm, and then the COS distance of depth map is calculated using matrix-vector multiplication, to match the similarity of key frame, winding detection is carried out to key frame, method provided by the invention has the invariance to illumination, it is able to achieve accurate positionin and the map structuring of robot.

Description

A kind of vision SLAM winding detection method and device merging depth information
Technical field
The present invention relates to robot simultaneous localization and mapping technical field, and in particular to a kind of fusion depth information Vision SLAM winding detection method and device.
Background technique
Since the appearance of bionics and intelligent robot technology, researchers just thirst for some day, and robot can As the mankind, by eyes go to observe and understand around the world, and can deftly autonomous in the natural environment, Realize man-machine harmony and co-existence.
Wherein, one it is important and fundamental problem is, how by the three-dimensional structure of two-dimensional image information analysis scenery, Determine camera in position wherein.The solution of this problem be unable to do without the research of a basic fundamental: while positioning and map structure (Simultaneous-Localizationand-Mapping, SLAM) is built, the SLAM technology of vision is based particularly on.
In order to achieve the effect that the SLAM technology of view-based access control model realizes that human eye is the same, as long as looking around surrounding, object is recognized, just It can judge the position of oneself, and be currently based on the algorithm of characteristic point and pixel, it is obviously far from enough from such purpose.Almost institute Closed loop detection method be all vision description to be carried out using key frame to environment, then by currently using visual sensing Image matched with key frame in map complete closed loop detection work.
On closed loop test problems, robot research work mainly stresses to solve two problems: first is to have to expand Property, images match suitable for overall situation because many mission requirements robots need to use thousands of or even million width Key frame describes environment, thus generates the requirement that can be expanded i.e. suitable for the high-speed, high precision image matching algorithm of overall situation. The problem that second needs solves should have environmental condition invariance when being images match, this is referred to various different items The image that acquires under part carries out accurate match, including the processing to illumination variation, and to dynamic environment, season, weather and The ability of visual angle change processing.
It is weaker to illumination invariant in current method, and robot how is improved to the invariance of illumination, to realize The accurate positionin of robot and map structuring are to be worth solving the problems, such as.
Summary of the invention
The purpose of the present invention is to provide a kind of vision SLAM winding detection method and device for merging depth information, it is intended to Robot is improved to the invariance of illumination, to realize accurate positionin and the map structuring of robot.
To achieve the goals above, the present invention the following technical schemes are provided:
The present invention provides a kind of vision SLAM winding detection method for merging depth information, comprising the following steps:
Step S100, the video streaming image shot in robot kinematics is obtained;
Step S200, the key frame in video flowing is extracted offline;
Step S300, the depth map of key frame is obtained with deep neural network training;
Step S400, the global characteristics descriptor of depth map is extracted using M2DP algorithm;
Step S500, the COS distance that depth map is calculated using matrix-vector multiplication, to match the similarity of key frame;
Step S600, winding detection is carried out to key frame.
Further, the video streaming image in the step S100 is acquired by the camera being set in robot.
Further, the step S300 is specifically included:
Step S310, the database of key frame relative depth is constructed;
Step S320, two picture points are randomly selected in same key frame, mark two figures in same key frame The relatively far and near information of picture point;
Step S330, the relative depth information among original image is obtained by the training of neural network;
Step S340, the image with object information is obtained, described image and original image are in the same size.
Further, the step S400 is specifically included: after depth map is transformed into a cloud, the plane that Xiang Ruogan is set is thrown Shadow generates 2D image descriptor, then generates 128 dimensions to the 2D image descriptor dimensionality reduction of overlapping by principal component analytical method Global characteristics descriptor.
Further, the COS distance of depth map is calculated in the step S500 using matrix-vector multiplication specifically: pass through Obtain the matrix-vector of key frame in current key frame and map, and using matrix-vector multiplication calculate the cosine of depth map away from From to obtain key frame similarity in current key frame and map.
Further, the step S600 is specifically included:
When key frame similarity reaches setting ratio in the current key frame and map, then winding detection has been determined Occur, so as to adjust map offset and update global map;When the current key frame is low with key frame similarity in map When setting ratio, then determine that there is no to create key frame and expand map for winding detection.
The present invention also provides a kind of vision SLAM winding detection device for merging depth information, described device includes: storage Device, processor and storage in the memory and the computer program that can run on the processor, the processor It executes the computer program and operates in lower module of described device:
Module is obtained, for obtaining the video streaming image shot in robot kinematics;
Abstraction module, for extracting the key frame in video flowing offline;
Training module, for obtaining the depth map of key frame with deep neural network training;
Extraction module, for extracting the global characteristics descriptor of depth map using M2DP algorithm;
Matching module, for calculating the COS distance of depth map using matrix-vector multiplication, to match the phase of key frame Like degree;
Detection module, for carrying out winding detection to key frame.
The beneficial effects of the present invention are: the present invention disclose it is a kind of merge depth information vision SLAM winding detection method and Device obtains the video streaming image shot in robot kinematics, and extracts the key frame in video streaming image offline, uses Deep neural network training obtains the depth map of key frame, and the global characteristics descriptor of depth map is extracted using M2DP algorithm, into And the COS distance for utilizing matrix-vector multiplication to calculate depth map returns key frame to match the similarity of key frame Ring detection, method provided by the invention have the invariance to illumination, are able to achieve accurate positionin and the map structuring of robot.
Detailed description of the invention
By the way that the embodiment in conjunction with shown by attached drawing is described in detail, above-mentioned and other features of the disclosure will More obvious, identical reference label indicates the same or similar element in disclosure attached drawing, it should be apparent that, it is described below Attached drawing be only some embodiments of the present disclosure, for those of ordinary skill in the art, do not making the creative labor Under the premise of, it is also possible to obtain other drawings based on these drawings, in the accompanying drawings:
Fig. 1 is a kind of flow chart for the vision SLAM winding detection method for merging depth information of the embodiment of the present invention;
Fig. 2 is a kind of structural schematic diagram for the vision SLAM winding detection device for merging depth information of the embodiment of the present invention.
Specific embodiment
Clear, complete description is carried out to technical solution of the present invention below in conjunction with attached drawing, it is clear that described implementation Example is a part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, ordinary skill Personnel are obtained without making creative work so other embodiments, belong to protection scope of the present invention.
As shown in Figure 1, a kind of vision SLAM winding detection method for merging depth information provided in an embodiment of the present invention, Robot operating system (Robot Operating System abbreviation ROS) is carried in 2 mobile robot of Turtlebot, it is upper Machine is set as NVIDIA TX2, and the Kinect V2 camera being loaded on Turtlebot 2 transmits video by ROS system and arrives In SLAM winding detection system;
Detection method includes the following steps for the winding:
Step S100, the video streaming image shot in robot kinematics is obtained;
Step S200, the key frame in video flowing is extracted offline;
Step S300, the depth map of key frame is obtained with deep neural network training;
Step S400, the global characteristics descriptor of depth map is extracted using M2DP algorithm;
Step S500, the COS distance that depth map is calculated using matrix-vector multiplication, to match the similarity of key frame;
Step S600, winding detection is carried out to key frame, provides reliable support for robot autonomous navigation.
Further, the video streaming image in the step S100 is acquired by the camera being set in robot.
Further, the method for the key frame in video flowing is extracted in the step S200 offline are as follows: detect using similarity Method, the detection method are based on perceptual hash algorithm, specifically include:
Step S210, the image in video flowing is extracted, and reduces the size of described image;
Step S220, simplify the color of image;
Step S230, the discrete cosine transform of image is calculated;
Step S240, the discrete cosine transform of downscaled images;
Step S250, the average value of image is calculated;
Step S260, the cryptographic Hash of image is calculated with Hamming distance method.
Further, the step S300 is specifically included:
Step S310, the database of key frame relative depth is constructed;
Step S320, two picture points are randomly selected in same key frame, mark two figures in same key frame The relatively far and near information of picture point;
Step S330, the relative depth information among original image is obtained by the training of neural network;
Step S340, the image with object information is obtained, described image and original image are in the same size.
Further, the step S400 is specifically included: after depth map is transformed into a cloud, the plane that Xiang Ruogan is set is thrown Shadow generates 2D image descriptor, then forms the complete of 128 dimensions to the 2D descriptor dimensionality reduction of overlapping by principal component analytical method Office's feature descriptor, the global characteristics descriptor succinctly can comprehensively express characteristics of image, though the 2D image descriptor Right redundancy is still conducive to point Yun Chongjian.
Specially following steps:
Step S410, three-dimensional space is defined, and sets the two-dimensional surface of n different location;
It step S420, will in OpenCV and PCL (Point Cloud Library point Yun Ku) using coordinate conversion relation Depth image is converted to m three dimensional point cloud;
Step S430, m three dimensional point cloud is normalized using principal component analytical method (PCA);
Step S440, m three dimensional point cloud is projected in respectively on n two-dimensional surface, obtains the n two-dimensional surfaces It is respectively provided with m subpoint;
Step S450, the point cloud data center after projecting in the n two-dimensional surfaces is calculated;
Step S460, using the point cloud data center as origin, calculate separately m subpoint to the n origin away from From to obtain n Vector Groups;
Step S470, the n vector is formed into matrix A, singular value decomposition then is carried out to matrix A, it will be in result First left singular vector and first right singular vector connect, to obtain the image descriptor of one 128 dimension.
Further, since the dimension of description vectors is all in 1K hereinafter, utilize matrix-vector multiplication meter in the step S500 Calculate the COS distance of depth map specifically: by obtaining the matrix-vector of key frame in current key frame and map, and utilize square Battle array vector multiplication calculates cosine (angle) distance of depth map, to obtain key frame similarity in current key frame and map.
Further, the step S600 is specifically included:
When key frame similarity reaches setting ratio in the current key frame and map, then winding detection has been determined Occur, so as to adjust map offset and update global map;When the current key frame is low with key frame similarity in map When setting ratio, then determine that there is no to create key frame and expand map for winding detection.
A kind of vision SLAM winding detection device for fusion depth information that embodiment of the disclosure provides, as shown in Figure 2 For a kind of vision SLAM winding detection device figure of fusion depth information of the disclosure, a kind of fusion depth information of the embodiment Vision SLAM winding detection device include: processor, memory and storage in the memory and can be in the processing The computer program run on device, the processor realize a kind of above-mentioned fusion depth information when executing the computer program Step in vision SLAM winding detection device embodiment.
Described device includes: memory, processor and storage in the memory and can transport on the processor Capable computer program, the processor execute the computer program and operate in lower module of described device:
Module is obtained, for obtaining the video streaming image shot in robot kinematics;
Abstraction module, for extracting the key frame in video flowing offline;
Training module, for obtaining the depth map of key frame with deep neural network training;
Extraction module, for extracting the global characteristics descriptor of depth map using M2DP algorithm;
Matching module, for calculating the COS distance of depth map using matrix-vector multiplication, to match the phase of key frame Like degree;
Detection module, for carrying out winding detection to key frame.
A kind of vision SLAM winding detection device merging depth information, include but are not limited to, processor is deposited Reservoir.It will be understood by those skilled in the art that the example is only a kind of vision SLAM winding detection for merging depth information The example of device does not constitute the restriction to a kind of vision SLAM winding detection device for merging depth information, may include ratio The more components of example perhaps combine certain components or different components, such as a kind of vision for merging depth information SLAM winding detection device can also be including input-output equipment etc..
Alleged processor can be central processing unit (Central-Processing-Unit, CPU), can also be it His general processor, digital signal processor (Digital-Signal-Processor, DSP), specific integrated circuit (Application-Specific-Integrated-Circuit, ASIC), ready-made programmable gate array (Field- Programmable-Gate-Array, FPGA) either other programmable logic device, discrete gate or transistor logic, Discrete hardware components etc..General processor can be microprocessor or the processor is also possible to any conventional processor Deng, the processor is a kind of control centre of vision SLAM winding detection device running gear for merging depth information, It can running gear using a kind of various interfaces and connection entire vision SLAM winding detection device for merging depth information Various pieces.
The memory can be used for storing the computer program and/or module, and the processor is by operation or executes Computer program in the memory and/or module are stored, and calls the data being stored in memory, described in realization A kind of various functions for the vision SLAM winding detection device merging depth information.The memory can mainly include storage program Area and storage data area, wherein storing program area can application program needed for storage program area, at least one function;Storage Data field can store the data of creation.In addition, memory may include high-speed random access memory, it can also include non-volatile Property memory, such as intelligent memory card (Smart-Media-Card, SMC), secure digital (Secure-Digital, SD) card, Flash card (Flash-Card), at least one disk memory, flush memory device or other volatile solid-state parts.
Although the description of the disclosure is quite detailed and especially several embodiments are described, it is not Any of these details or embodiment or any specific embodiments are intended to be limited to, but should be considered as is by reference to appended A possibility that claim provides broad sense in view of the prior art for these claims explanation, to effectively cover the disclosure Preset range.In addition, the disclosure is described with inventor's foreseeable embodiment above, its purpose is to be provided with Description, and those equivalent modifications that the disclosure can be still represented to the unsubstantiality change of the disclosure still unforeseen at present.

Claims (7)

1. a kind of vision SLAM winding detection method for merging depth information, which comprises the following steps:
Step S100, the video streaming image shot in robot kinematics is obtained;
Step S200, the key frame in video flowing is extracted offline;
Step S300, the depth map of key frame is obtained with deep neural network training;
Step S400, the global characteristics descriptor of depth map is extracted using M2DP algorithm;
Step S500, the COS distance that depth map is calculated using matrix-vector multiplication, to match the similarity of key frame;
Step S600, winding detection is carried out to key frame.
2. a kind of vision SLAM winding detection method for merging depth information according to claim 1, which is characterized in that institute The video streaming image stated in step S100 is acquired by the camera being set in robot.
3. a kind of vision SLAM winding detection method for merging depth information according to claim 1, which is characterized in that institute Step S300 is stated to specifically include:
Step S310, the database of key frame relative depth is constructed;
Step S320, two picture points are randomly selected in same key frame, mark two described image points in same key frame Relatively far and near information;
Step S330, the relative depth information among original image is obtained by the training of neural network;
Step S340, the image with object information is obtained, described image and original image are in the same size.
4. a kind of vision SLAM winding detection method for merging depth information according to claim 1, which is characterized in that institute State step S400 to specifically include: after depth map is transformed into a cloud, the plane projection that Xiang Ruogan is set generates 2D iamge description Then symbol generates the global characteristics descriptor of 128 dimensions to the 2D image descriptor dimensionality reduction of overlapping by principal component analytical method.
5. a kind of vision SLAM winding detection method for merging depth information according to claim 1, which is characterized in that institute State the COS distance for calculating depth map in step S500 using matrix-vector multiplication specifically:
Depth map is calculated by obtaining the matrix-vector of key frame in current key frame and map, and using matrix-vector multiplication COS distance, to obtain key frame similarity in current key frame and map.
6. a kind of vision SLAM winding detection method for merging depth information according to claim 5, which is characterized in that institute Step S600 is stated to specifically include:
When key frame similarity reaches setting ratio in the current key frame and map, then determine that winding detection has been sent out It is raw, so as to adjust map offset and update global map;When the current key frame and key frame similarity in map are lower than When setting ratio, then determine that there is no to create key frame and expand map for winding detection.
7. it is a kind of merge depth information vision SLAM winding detection device, which is characterized in that described device include: memory, Processor and storage in the memory and the computer program that can run on the processor, the processor execution The computer program operates in lower module of described device:
Module is obtained, for obtaining the video streaming image shot in robot kinematics;
Abstraction module, for extracting the key frame in video flowing offline;
Training module, for obtaining the depth map of key frame with deep neural network training;
Extraction module, for extracting the global characteristics descriptor of depth map using M2DP algorithm;
Matching module, for calculating the COS distance of depth map using matrix-vector multiplication, to match the similarity of key frame;
Detection module, for carrying out winding detection to key frame.
CN201811632974.6A 2018-12-29 2018-12-29 A kind of vision SLAM winding detection method and device merging depth information Pending CN109784232A (en)

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Application publication date: 20190521