A kind of environmental characteristic expression based on 3 d grid map and knowledge method for distinguishing
Technical field
The discrete orthogonal transforms technologies such as the present invention relates to artificial intelligence, pattern-recognition and Fourier to convert, Walsh transformation,
Especially robot to the modeling of the three-dimensional environment of complex environment with know method for distinguishing, be applied to the Context awareness of robot with it is autonomous
In terms of movement.
Background technology
With industrial machine man-based development in recent years, the gradual turn up of service robot industry has been driven, while from 2014
The Intelligent hardware field that year starts also begins to protrusion, according to the statistics of international alliance of robot, service robot sale in 2015
Volume will be up to 8,500,000,000 dollars, and higher 20%~30% growth rate is kept to be studied according to Ai Rui in Intelligent hardware field, and 2014
Year, global Intelligent hardware installation amount reached 6,000,000,000, it is contemplated that 2017 will be more than 14,000,000,000.
The behind of high speed development in market, problem is equally apparent, and the potentiality in one side market are also excavated far away, another
Aspect, robot and Intelligent hardware enter service industry, and there is also the features of some technological difficulties, especially three-dimensional environment to build
Mould and identification technology, such as robot enter in actual home environment, carry out Context awareness and safely autonomous etc.,
All there are certain technological difficulties at present.
Goal of the invention
The main object of the present invention be exactly environmental characteristic after solving the environmental modeling based on 3 d grid map indicate with
Identification problem, it provides a kind of method so that the environmental characteristic based on 3 d grid map convenient for storage and calculates, to reach
To the purpose for facilitating identification, technical support is provided for other practical applications.It can be, but not limited to apply in the machine towards family
People plays and robot cleaner aspect.
Technical solution
The object of the present invention is achieved like this:By three-dimensional laser radar or binocular vision sensor, obtain
The 3 d grid cartographic information of actual environment indicates system by environmental characteristic, calculates and the feature of storage volume elements to three-dimensional grid
In lattice map, after the information for setting required target volume elements, by environmental characteristic identifying system, matched in 3 d grid map
Go out all required candidate volume elements.It includes the following steps:
(1) in environmental characteristic expression system, it is contemplated that the convenience of calculating, we set an influence distance delta, i.e. obstacle
For object member to the coverage of periphery volume elements, σ can be but not limited to Euclidean distance, Manhattan (Manhattan) distance etc..Together
When also for convenience of calculation, volume elements x on impacted all average discretes to eight yaw faces of volume elements x;δ0, δπ/4, δπ/2,
δ3π/4, δπ, δ5π/4, δ3π/2, δ7π/4], then each yaw face δiInterior influence component is all discrete to arrive yaw face δiInterior eight bow
[ on the elevation angle;η0, ηπ/12, ηπ/4, η5π/12, η7π/12, η3π/4, η11π/12, ηπ], the suffered influence matrix f (x) of volume elements x is formed, and count
The eigenmatrix and characteristic spectrum for calculating the suffered influence matrix f (x) of volume elements x, provide two kinds of eigenmatrixes and the meter of characteristic spectrum here
Calculation method,
(2) in environmental characteristic expression system, each element of the influence matrix of each idle volume elements is initialized as 0,
Influence of each barrier volume elements to all volume elements in σ distances is analyzed one by one, for example, during analysis, obstructing objects
Yaw angles of first ξ with respect to volume elements x is θ, pitch angle β, and distance is d, d≤σ, then influences of the barrier volume elements ξ to volume elements x
Function can be but not limited to f (xβ, θ, d)=1/d, if θ just on a certain yaw face of volume elements x, directly this partially
It is superimposed on movable surface, if θ, between certain two yaw face, such as θ ∈ (π/4, pi/2) are then decomposed according to vector, f
(xβ, θ, d) decompose project to yaw face δπ/4On vector faWith yaw face δπ/2On vector fb(two projection vector faWith fbSame Z
Axle clamp angle is equal, and with f (xβ, θ, d) coplanar), by same vector decomposition method again respectively vector faWith fbDecomposition projects to
On two neighboring pitching angular direction in each yaw face, after the completion of to all obstructing objects meta analysis, each volume elements
Influence matrix has calculated completion, and is stored in grid, is denoted as:
(3) in environmental characteristic expression system, it is contemplated that the convenience of calculating, we seek the eigenmatrix F (x) of f (x),
And it is stored in grid:
Method one seeks F (x) by two-dimensional fourier transform, enables transformation operatorAccording to fast two-dimensional
Fourier transformation calculations obtain,
Method two seeks F (x) by Walsh transformation, enables transformation operatorAccording to fast two-dimensional Walsh
Hadama changes convert,
8x8 matrixes in above-mentioned formula, are the Walsh Hadama transformation matrixs of 8 dimensions, and different dimensions is corresponding
Walsh Hadama transformation matrixs are different, wherein:
(4) in environmental characteristic expression system, it is contemplated that the convenience of calculating, we seek the characteristic spectrum of eigenmatrix F (x)
P (x), and be stored in grid:Method one converts eigenmatrix F (x), the Wo Menyou found out according to fast two-dimensional Fourier,
Pass through modulus operation, feature spectral element P (x);i][j]=|F(x)[i][j]=|FI+1, j+1|, i, j ∈ [0,7]
Method two converts eigenmatrix F (x), the Wo Menyou found out according to fast two-dimensional Walsh Hadama,
(5) in environmental characteristic identifying system, we are given threshold deg reethreshold, and construct target environment volume elements y
Influence matrixTwo dimension Walsh Hadama transform methods are used according to above step, are asked
Corresponding characteristic spectrum P (y) is taken, all volume elements x are searched on 3 d grid map, and compare corresponding characteristic spectrum, note vector P
(x) angle between vector P (y) is ∠ (P (x), P (y))≤deg reethreshold, calculateIf cos ∠ (P (x), P (y)) >=cos (deg reethreshold), with regard to table
Show that volume elements x with target volume elements y is similar in the actual environment, match volume elements of one of candidate,
(6) passing through environmental characteristic expression and identifying system, we can successfully find out all environment with object matching,
Support is provided for subsequent applications.
System composition used in the present invention is as follows:Environmental characteristic indicates system, environmental characteristic identifying system.This two are
System is the software systems according to function setting, and each subsystem concrete function is as follows:
* environmental characteristic indicates system:On existing 3 d grid map, relevant volume elements is analyzed, calculates simultaneously memory bank
The influence matrix of member, eigenmatrix, characteristic spectrum,
* environmental characteristic identifying system:The corresponding volume elements influence matrix of desired environment is provided, in have volume elements feature three
It ties up to search on grating map and search, match all volume elements similar with desired environment.
Description of the drawings:
Fig. 1 is the method for the present invention system for use in carrying composition figure
Fig. 2 (a) is 3 d grid map, is (b) the influence vector and decomposition method of volume elements, is (c) that the decomposition of yaw face is shown
It is intended to
Fig. 3 (a) is the yaw face of volume elements and the discretization of pitch angle, is (b) matrix after discretization
Fig. 4 is the schematic diagram of Yishanmen
Specific implementation mode
Below in conjunction with the accompanying drawings, illustrate embodiments of the present invention.
Overall system architecture used in the method for the present invention can refer to Fig. 1, it is made of two subsystems, specifically comprising as follows
Step:
The first step
First, environmental characteristic indicates that system, definition distance are Euclidean distance, and setting influences distance delta=4, i.e. obstructing objects
Member only influences the volume elements within peripheral distance 4, if Fig. 2 (a) is the 3 d grid map of environment, the shadow of Fig. 2 (b) barrier volume elements
Ring vector and decomposition method:
f(xβ, θ, d)=f1+f2
=f1+f3+f4(f3With f4It is f2Component on two adjacent yaw faces)
=f '3+f′4+f3+f4(f1By f3With f4The long ratio of mould resolve into f '3With f '4)
=(f '3+f3)+(f′4+f4)
=fa+fb(faWith fbIt is equal with Z axis angle)
By shown in Fig. 3 (a) discrete to eight of the influence of volume elements yaw faces on eight pitch angles, it is discrete after matrix such as
Shown in Fig. 3 (b).
Secondly, environmental characteristic identifying system, setting deg reethreshold=5 °.
Second step
Environmental characteristic indicates system, initializes the element f of the influence matrix of each volume elementsij=0, i, j ∈ [1,8], one by one
Each volume elements in 3 d grid map is scanned, to each influence of the barrier volume elements total calculation to periphery volume elements.
For example, as shown in figure 4, barrier volume elements (1,1,1) is to the influence f (x of volume elements (2,1,1)Pi/2, π, 1)=1, to this
It influences in discretization to the yaw face of volume elements (2,1,1) and pitch angle, is apparent from f (xPi/2, π, 1) just in yaw face δπOn, and bowing
Elevation angle η5π/12With η7π/12Between, so in such a way that vector decomposes, it only need to be f (xPi/2, π, 1) project to pitch angle η5π/12With
η7π/12It is upper, f (x are known by Fig. 2 and Fig. 3Pi/2, π, 1) decompose later obtain:
Similarly, influence of the barrier volume elements (1,2,1) to volume elements (2,1,1)It is discrete to arrive yaw face
δ3π/4On pitch angle η5π/12With η7π/12On, after decomposition:
Influence of the barrier volume elements (1,3,1) to volume elements (2,1,1)It is discrete to arrive yaw face
δ3π/4With yaw face δπ/2It is respectively after upper:
Again faWith fbPitch angle η on yaw face belonging to projecting to5π/12With η7π/12On, it decomposes
Afterwards:
Influence of the barrier volume elements (1,1,2) to volume elements (2,1,1)It is discrete to arrive yaw face δπOn bow
Elevation angle ηπ/4On, after decomposition:
Influence of the barrier volume elements (1,2,2) to volume elements (2,1,1)It is discrete to arrive yaw face δ3π/4
On pitch angle ηπ/4With η5π/12On, after decomposition:
Influence of the barrier volume elements (1,3,2) to volume elements (2,1,1)It is discrete to arrive yaw face
δ3π/4With yaw face δπ/2It is respectively after upper (coordinate representation in each yaw face, do not consider directionality):
Again faWith fbPitch angle η on yaw face belonging to projecting to5π/12With ηπ/4On, it is as follows:
After decomposition:
Influence of the barrier volume elements (1,1,3) to volume elements (2,1,1)It is discrete to arrive yaw face δπOn
Pitch angle η5π/12With ηπ/4After upper:
Influence of the barrier volume elements (1,2,3) to volume elements (2,1,1)It is discrete to arrive yaw face δ3π/4
On pitch angle ηπ/4With ηπ/12On, after decomposition:
Influence of the barrier volume elements (1,3,3) to volume elements (2,1,1)It is discrete to arrive yaw face
δ3π/4With yaw face δπ/2It is respectively after upper:
Again faWith fbPitch angle η on yaw face belonging to projecting to5π/12With ηπ/4On, it is as follows:
After decomposition:
To sum up, the influence matrix suffered by volume elements (2,1,1)
Third walks
The eigenmatrix F of the influence matrix f (2,1,1) of volume elements (2,1,1) is found out according to Fast W alsh Hadama transformation
(2,1,1), Wo Menyou:
4th step
The characteristic spectrum P (2,1,1) that volume elements (2,1,1) is found out according to Fast W alsh Hadama transformation, by the spy of previous step
Levying matrix F (2,1,1), we have:
P (2,1,1)=[0.0051,0.0001,0.0057,0.0325]
5th step
In environmental characteristic identifying system, such as we are interested in Yishanmen, we want to look on 3 d grid map
Place near to door constructs the influence matrix of this fitting of door environment first, as follows:
Similarly we have:
P (door)=s [0.0045,0.0003,0.0064,0.0336]
6th step
By environmental characteristic identifying system, entire 3 d grid map is searched for, searches and all matches with P (door)
Volume elements, such as we compare P (2,1,1) and P (door)
Cos ∠ (P (2,1,1), P (door))=0.999625 >=cos (deg reethreshold)=0.996195
Similarly, we are interested in another Yishanmen, we want to find the place near door, ring on 3 d grid map
The influence matrix in border is as follows:
Equally we have:
P ' (door)=s [0.0045,0.0003,0.0064,0.0336]
To sum up, it may be seen that characteristic spectrum P (door) and the P ' (door) of f (door) and f ' (door) is identical,
It is in the actual environment and similar, it is indicated by our environmental characteristics and identifying system, it can be these whole of " door " environment
It allots, this has just absolutely proved our system, has rotational invariance for similar environment, in the mistake of environmental characteristic identification
Cheng Zhong is considerably reduced exhaustive comparison number, and the efficiency of entire method is high, the time complexity and grid of entire method
The size of lattice map is linear.