Summary of the invention
Purpose of this disclosure is to provide SLAM method, apparatus, storage medium and the equipment of a kind of view-based access control model inertia, to
Solve the problems, such as the computational efficiency and positioning accuracy existing in the prior art for being difficult to take into account SLAM.
To achieve the goals above, according to the first aspect of the embodiments of the present disclosure, a kind of view-based access control model inertia is provided
SLAM method, which comprises
The motion information of the image information of first moment image acquisition units acquisition and Inertial Measurement Unit IMU acquisition is pressed
It is merged according to expanded Kalman filtration algorithm, to obtain initial pose;
According to described image information and the initial pose, initial local map is determined;
The initial pose and the initial local map are optimized according to preset nonlinear optimization algorithm, to obtain
Take optimization pose and optimization local map;
According to the optimization pose and the optimization local map, more fresh target initial bit appearance and target initial local
Figure, the initial pose of target is that the image information for acquiring the second moment described image acquisition unit and the IMU are acquired
Motion information is merged according to the expanded Kalman filtration algorithm, the initial pose of acquisition, the target initial local
Figure be determined according to the image information and the initial pose of the target of the second moment described image acquisition unit acquisition just
Beginning local map, second moment are at the time of obtaining the optimization pose and the optimization local map.
Optionally, described to acquire the image information of the first moment image acquisition units acquisition and Inertial Measurement Unit IMU
Motion information merged according to expanded Kalman filtration algorithm, to obtain initial pose, comprising:
It is defeated to obtain the IMU motion model using the motion information and history pose as the input of IMU motion model
Prediction pose out, the history pose are the image information for acquiring third moment described image acquisition unit and the IMU
The motion information of acquisition is merged according to the expanded Kalman filtration algorithm, the initial pose of acquisition, the third moment
At the time of for before first moment;
Described image information is handled according to preset image processing algorithm, to obtain the vision for including in described image information
The constraint relationship;
The prediction pose is updated according to the Vision Constraints relationship, to obtain the initial pose, the view
Feel that the constraint relationship includes: that re-projection error is minimum or luminosity error is minimum.
Optionally, described according to described image information and the initial pose, determine initial local map, comprising:
The pixel for meeting preset condition in described image information is determined as characteristic point;
Three-dimensional reconstruction is carried out according to the characteristic point and the initial pose, to obtain the initial local map.
Optionally, it is described according to preset nonlinear optimization algorithm to the initial pose and the initial local map into
Row optimization, to obtain optimization pose and optimization local map, comprising:
When described image information is key frame, according to the initial pose, the initial local map and described first
The crucial posture information of preset quantity before moment establishes objective function, and the objective function includes that the measurement of the IMU is residual
The measurement residual error of difference and described image acquisition unit, the key posture information is the first moment foregoing description Image Acquisition
When the history image information of unit acquisition is key frame, the posture information that includes in the history image information;
The objective function is iterated according to preset algorithm, it is right under the conditions of the objective function is the smallest to obtain
The optimization pose answered and the optimization local map.
Optionally, described according to the optimization pose and the optimization local map, more fresh target initial bit appearance and target
Initial local map, comprising:
It is the optimization local map by the target initial local map rejuvenation;
When the Vision Constraints relationship is re-projection error minimum, by the optimization pose and pre- before the second moment
If quantity key posture information is merged according to Kalman filtering algorithm, the initial pose of the target is updated to described
The pose of Kalman filtering algorithm output, the key posture information are that the second moment foregoing description image acquisition units are adopted
When the history image information integrated is key frame, the posture information that includes in the history image information;
When the Vision Constraints relationship is luminosity error minimum, obtain between the initial pose and the optimization pose
Offset;
The initial pose of target is updated according to the offset.
Optionally, described according to the optimization pose and the optimization local map, more fresh target initial bit appearance and target
Initial local map, further includes:
The updated target initial local map is stored in global map.
According to the second aspect of an embodiment of the present disclosure, a kind of SLAM device of view-based access control model inertia, described device packet are provided
It includes:
Fusion Module, image information and Inertial Measurement Unit IMU for acquiring the first moment image acquisition units are adopted
The motion information of collection is merged according to expanded Kalman filtration algorithm, to obtain initial pose;
Determining module, for determining initial local map according to described image information and the initial pose;
Optimization module is used for according to preset nonlinear optimization algorithm to the initial pose and the initial local map
It optimizes, to obtain optimization pose and optimization local map;
Update module, for according to the optimization pose and the optimization local map, more fresh target initial bit appearance and mesh
Initial local map is marked, the initial pose of target is the image information for acquiring the second moment described image acquisition unit and institute
The motion information for stating IMU acquisition is merged according to the expanded Kalman filtration algorithm, the initial pose of acquisition, the target
Initial local map is the image information and the target initial bit acquired according to the second moment described image acquisition unit
The initial local map that appearance determines, second moment are at the time of obtaining the optimization pose and the optimization local map.
Optionally, the Fusion Module includes:
Submodule is predicted, for using the motion information and history pose as the input of IMU motion model, to obtain
The prediction pose of IMU motion model output is stated, the history pose is the figure for acquiring third moment described image acquisition unit
As information and the IMU motion information acquired are merged according to the expanded Kalman filtration algorithm, the initial bit of acquisition
Appearance, at the time of the third moment is before first moment;
Image procossing submodule, for handling described image information according to preset image processing algorithm, described in obtaining
The Vision Constraints relationship for including in image information;
Submodule is updated, for being updated according to the Vision Constraints relationship to the prediction pose, described in obtaining
Initial pose, the Vision Constraints relationship include: that re-projection error is minimum or luminosity error is minimum.
Optionally, the determining module includes:
Submodule is determined, for the pixel for meeting preset condition in described image information to be determined as characteristic point;
Figure submodule is built, it is described first to obtain for carrying out three-dimensional reconstruction according to the characteristic point and the initial pose
Beginning local map.
Optionally, the optimization module includes:
Setting up submodule is used for when described image information is key frame, according to the initial pose, the initial local
Map and the crucial posture information of preset quantity before first moment establish objective function, and the objective function includes institute
State IMU measurement residual sum described image acquisition unit measurement residual error, it is described key posture information be first moment it
When the history image information of preceding described image acquisition unit acquisition is key frame, the pose for including in the history image information is believed
Breath;
Iteration submodule, for being iterated according to preset algorithm to the objective function, to obtain in the target letter
The corresponding optimization pose and the optimization local map under the conditions of number is the smallest.
Optionally, the update module includes:
Map rejuvenation submodule, for being the optimization local map by the target initial local map rejuvenation;
Pose updates submodule, is used for when the Vision Constraints relationship is re-projection error minimum, by the optimization position
Appearance and the crucial posture information of preset quantity before the second moment are merged according to Kalman filtering algorithm, by the mesh
Mark the pose that initial pose is updated to Kalman filtering algorithm output, the key posture information be second moment it
When the history image information of preceding described image acquisition unit acquisition is key frame, the pose for including in the history image information is believed
Breath;
The pose updates submodule, is also used to when the Vision Constraints relationship is luminosity error minimum, described in acquisition
Offset between initial pose and the optimization pose, and the initial pose of target is updated according to the offset.
Optionally, the map rejuvenation submodule is also used to the updated target initial local map deposit is complete
Local figure.
According to the third aspect of an embodiment of the present disclosure, a kind of computer readable storage medium is provided, calculating is stored thereon with
The step of machine program, the SLAM method for the view-based access control model inertia that realization first aspect provides when which is executed by processor.
According to a fourth aspect of embodiments of the present disclosure, a kind of electronic equipment is provided, comprising:
Memory is stored thereon with computer program;
Processor, for executing the computer program in the memory, with realize first aspect provide based on
The step of SLAM method of vision inertia.
Through the above technical solutions, the disclosure first believes image acquisition units and IMU in the image that the first moment acquired
Breath and motion information are merged according to expanded Kalman filtration algorithm, to obtain initial pose, further according to image information and just
Beginning pose determines initial local map, later according to preset nonlinear optimization algorithm to the initial pose and described initial
Local map optimizes, to obtain optimization pose and optimization local map, finally according to the optimization pose and the optimization
Local map updates the initial pose of the second moment corresponding target and target initial local map.By the way that spreading kalman is filtered
Input of the output of wave algorithm as nonlinear optimization algorithm, and extension karr is corrected using the output of nonlinear optimization algorithm
The output of graceful filtering algorithm, to improve the computational efficiency and positioning accuracy of SLAM.
Other feature and advantage of the disclosure will the following detailed description will be given in the detailed implementation section.
Specific embodiment
Example embodiments are described in detail here, and the example is illustrated in the accompanying drawings.Following description is related to
When attached drawing, unless otherwise indicated, the same numbers in different drawings indicate the same or similar elements.Following exemplary embodiment
Described in embodiment do not represent all implementations consistent with this disclosure.On the contrary, they be only with it is such as appended
The example of the consistent device and method of some aspects be described in detail in claims, the disclosure.
Before the SLAM method, apparatus of view-based access control model inertia of disclosure offer, storage medium and equipment are provided, first
Application scenarios involved by each embodiment of the disclosure are introduced.The application scenarios can be any terminal for needing SLAM
(such as: robot), can be set that there are two types of information collecting devices in the terminal, comprising: image acquisition units and IMU (English:
Inertial Measurement Unit, Chinese: Inertial Measurement Unit).Wherein, image acquisition units for example can be camera shooting
Head or camera may include: the sensors such as gyroscope, accelerometer in IMU, and image acquisition units and IMU can be fixed on one
Rise (i.e. image acquisition units with the position consistency where IMU), with ensure image acquisition units acquired image information with
The motion information of IMU acquisition is with uniformity.
Fig. 1 is a kind of flow chart of the SLAM method of view-based access control model inertia shown according to an exemplary embodiment, such as Fig. 1
It is shown, method includes the following steps:
Step 101, by the fortune of the image information of the first moment image acquisition units acquisition and Inertial Measurement Unit IMU acquisition
Dynamic information is merged according to expanded Kalman filtration algorithm, to obtain initial pose.
Step 102, according to image information and initial pose, initial local map is determined.
For example, the image for obtaining physical environment locating for the terminal that image acquisition units acquires at the first moment first is believed
Motion information corresponding with the terminal that IMU is acquired at the first moment is ceased, motion information for example may include: the orientation of terminal, position
It sets, speed, amount of bias etc..Wherein, pose, then root can be predicted by inertia measurement by the terminal for including in motion information
Prediction pose is updated according to the Vision Constraints relationship (can be understood as observational equation) for including in image information, to determine terminal
Pose.Image is believed according to expanded Kalman filtration algorithm (English: Extended Kalman Filtering, abbreviation: EKF)
Breath and motion information are merged, to obtain terminal in the initial pose and initial local map at the first moment.Spreading kalman
Filtering algorithm calculates comparatively fast, and the occupancy of CPU memory is lower, therefore computational efficiency is high.It is possible, firstly, to which motion information is made
For the input of the expanded Kalman filtration algorithm equation of motion, rough prediction is carried out to the pose of terminal, to obtain extension karr
The prediction pose of graceful filtering algorithm equation of motion output.Since the sensor for including in IMU is usually the sensor of consumption levels,
Error is larger, be easy to cause drift, can be further according to the Vision Constraints relationship for including in image information as extension karr
The observational equation of graceful filtering algorithm is updated the pose of terminal, to obtain initial pose.
Further, image information can be handled according to preset image processing method, to extract image information
In include texture information obtain capableing of the initial of reactive terminal local environment locating for the first moment in conjunction with initial pose
Local map.It should be noted that initial local map is the preset quantity acquired by image acquisition units before the first moment
In a key frame, the local map for the road sign point composition that can be observed, it can be understood as pre-set a sliding time
Window, for the N-1 key frame and the first moment corresponding image information before storing for the first moment.Initial local map
It is corresponding relationship with sliding time window, when the key frame in sliding time window updates, initial local map is also corresponded to
It updates.
Step 103, initial pose and initial local map are optimized according to preset nonlinear optimization algorithm, to obtain
Take optimization pose and optimization local map.
It is exemplary, since the positioning accuracy of EFK algorithm is lower, initial pose and initial local map can obtained
Afterwards, preset nonlinear optimization algorithm is selected, BA (English: Bundle is carried out to initial pose and initial local map
Adjustment, Chinese: bundle adjustment) optimization, to obtain the higher optimization pose of positioning accuracy and optimization local map.It can
To be interpreted as, using initial pose and initial local map as nonlinear optimization algorithm initial value, nonlinear optimization can be made to calculate
Method more rapid convergence (i.e. computational efficiency is higher), and obtain more accurately positioning.
For example, can be first according to the measurement residual error of IMU (English: Measurement Residual) and image acquisition units
Measurement residual error establish an objective function, initial pose and initial local map are brought into objective function, recycled non-
Linear optimization method is iterated objective function, until objective function reaches optimum state (i.e. minimum objective function), this
When objective function determine pose and local map be optimize pose and optimization local map.Wherein, nonlinear optimization algorithm
It may include: Gaussian-Newton method, LM (English: Levenberg-Marquardt algorithm, Chinese: Lai Wenbei
Lattice-Marquart algorithm) optimize scheduling algorithm, the disclosure is not specifically limited nonlinear optimization algorithm.
Step 104, according to optimization pose and optimization local map, more fresh target initial bit appearance and target initial local
Figure, the initial pose of target be the motion information that acquires of the image information for acquiring the second moment image acquisition units and IMU according to
Expanded Kalman filtration algorithm is merged, the initial pose of acquisition, and target initial local map is according to the second moment image
The initial local map that the image information and the initial pose of target of acquisition unit acquisition determine, the second moment are to obtain optimization pose
At the time of with optimization local map.
It is exemplary, obtaining the higher optimization pose of positioning accuracy and optimization local map, can will optimization pose and
Optimization local map is fed back in step 101 and step 102, to utilize expanded Kalman filtration algorithm true in Optimization Steps 101
The target initial local map determined in the initial pose of fixed target and step 102, to improve the positioning accuracy of SLAM.It needs
Illustrate, since expanded Kalman filtration algorithm is different with the computational efficiency of nonlinear optimization algorithm, step 101, step
Rapid 102 and step 103 may be performed simultaneously, it can be interpreted as step 101, step 102 and step 103 respectively correspond two can
With the thread executed parallel, such as step 101 and step 102 are front end thread, and step 103 is rear end thread, and front end thread is not
It needs to wait rear end thread, can execute always.Front end thread is determining the first moment corresponding initial pose and initial local
After map, initial pose and initial local map are sent to rear end thread, optimization pose and optimization office are determined by rear end thread
Portion's map, rear end thread will optimize pose at the second moment and optimization local map feeds back to front end thread, Lai Youhua front end of line
The initial pose of target and target initial local map that journey determines at the second moment.
After step 101 has determined the first moment corresponding initial pose and initial local map, when can continue first
The image letter of subsequent time (it is to be understood that subsequent time=first moment+T) image acquisition units and IMU acquisition after quarter
Breath and motion information are merged, to obtain the corresponding initial pose of subsequent time and initial local map.And step 102 is right
First moment corresponding initial pose and initial local map optimize, to obtain optimization pose and optimize local map, by
It is taken a long time in the iterative process of nonlinear optimization algorithm, therefore the time for obtaining optimization pose and optimization local map has been
At the second moment, there may be multiple T (usually a few tens of milliseconds), i.e. the second moment=the first between the second moment and the first moment
Moment+x*T.Step 101 is executing always, therefore in the second moment, the figure that the second moment image acquisition units and IMU are acquired
As information and motion information are merged, the initial pose of the second moment corresponding target got and target initial local
Figure.At this point, the first moment corresponding initial pose and initial local map are no longer valid, do not have practical significance, it is possible to
According to optimization pose and optimization local map, the initial pose of the second moment corresponding target and target initial local map are updated,
To improve positioning accuracy.
In conclusion image information and movement that the disclosure first acquires image acquisition units and IMU at the first moment
Information is merged according to expanded Kalman filtration algorithm, to obtain initial pose, is come further according to image information and initial pose
Initial local map is determined, later according to preset nonlinear optimization algorithm to the initial pose and the initial local map
It optimizes, to obtain optimization pose and optimization local map, finally according to the optimization pose and the optimization local map,
Update the initial pose of the second moment corresponding target and target initial local map.By by the defeated of expanded Kalman filtration algorithm
Out as the input of nonlinear optimization algorithm, and expanded Kalman filtration algorithm is corrected using the output of nonlinear optimization algorithm
Output, to improve the computational efficiency and positioning accuracy of SLAM.
Fig. 2 is the flow chart of the SLAM method of another view-based access control model inertia shown according to an exemplary embodiment, such as
Shown in Fig. 2, step 101 can be accomplished by the following way:
Step 1011, using motion information and history pose as the input of IMU motion model, to obtain IMU motion model
The prediction pose of output, history pose are the movement of the image information for acquiring third moment image acquisition units and IMU acquisition
Information is merged according to expanded Kalman filtration algorithm, the initial pose of acquisition, the third moment be the first moment before when
It carves.
Step 1012, image information is handled according to preset image processing algorithm, to obtain the view for including in image information
Feel the constraint relationship.
Step 1013, prediction pose is updated according to Vision Constraints relationship, to obtain initial pose, Vision Constraints are closed
System includes: that re-projection error is minimum or luminosity error is minimum.
Expanded Kalman filtration algorithm in the disclosure may include two kinds: MSCKF (English: Multi-State
Constraint Kalman Filter, Chinese: multimode constraint Kalman filter) algorithm and ROVIO (English: Robust
Visual Inertial Odometry, Chinese: robust vision inertia odometer) algorithm.Two kinds of algorithms are all made of IMU movement mould
Type is as the expanded Kalman filtration algorithm equation of motion, and to obtain prediction pose, and the Vision Constraints relationship in MSCKF algorithm is
Re-projection error is minimum, in this, as observational equation, is updated to prediction pose, the Vision Constraints relationship in ROVIO algorithm
It is luminosity error minimum in this, as observational equation, prediction pose is updated.
Fig. 3 is the flow chart of the SLAM method of another view-based access control model inertia shown according to an exemplary embodiment, such as
Shown in Fig. 3, step 102 be may comprise steps of:
Step 1021, the pixel that preset condition is met in image information is determined as characteristic point.
Step 1022, three-dimensional reconstruction is carried out according to characteristic point and initial pose, to obtain initial local map.
Exemplary, the acquisition modes of initial local map can be first choose in image information and meet preset condition
Pixel is as characteristic point.Wherein, characteristic point can be it is multiple (such as;100), preset condition for example may is that with it is adjacent
Luminance difference between pixel is greater than the point of preset luminance threshold.The characteristic point for recycling multiple moment to be mutually matched later
Three-dimensional reconstruction is carried out with the initial pose determined in step 101, it being capable of reactive terminal office locating for the first moment to obtain one
Portion's environment, three-dimensional initial local map.
The realization of two kinds of algorithms is illustrated individually below:
In MSCKF algorithm, i.e., Vision Constraints relationship is that re-projection error is minimum, and the pose obtained in step 1011 is believed
Breath, motion information and preset quantity key posture information before the first moment (such as can as the input of IMU motion model
With the newest crucial posture information before being the first moment), to obtain the prediction pose of IMU motion model output.
For example, input MSCKF algorithm state vector to be estimated can beIts
In, For the motion information for the IMU that MSCKF measurement obtains,For orientation of the IMU under global coordinate system,For the amount of bias of gyroscope,For speed of the IMU under global coordinate system,For the amount of bias of accelerometer,For position of the IMU under global coordinate system,For the pose obtained in step 1011
Information,For i-th of crucial posture information in N-1 before the first moment crucial posture information,For i-th of key
Orientation of the image acquisition units under global coordinate system in posture information,For Image Acquisition in i-th of crucial posture information
Position of the unit under global coordinate system.Using the output of IMU motion model as prediction pose, drift about since IMU exists,
It predicts that pose is not accurate enough, further, according to the minimum Vision Constraints relationship of re-projection error, prediction pose is updated,
Obtained pose is initial pose.
It should be noted that IMU motion model, describes the constraint relationship between posture information and motion information, due to
Image acquisition units and IMU are fixed together, therefore image information and motion information are with uniformity, such as: acceleration measuring
The acceleration measured is to time quadratic integral, and obtained value should be identical as the position in posture information, and gyroscope measures
To time integral, obtained value should be mutually same with the orientation in posture information in the orientation arrived.
Crucial posture information is understood that a certain moment should when the image information of image acquisition units acquisition is key frame
The posture information for including in moment image information.The crucial posture information of preset quantity before first moment, it can be understood as
The time window for pre-setting a sliding, for storing N number of posture information, comprising: N-1 before the first moment is crucial
Posture information and the first moment corresponding posture information.Wherein, judge image information whether be key frame rule, can be
By the image information compared with the image information that the previous keyframe moment obtains carries out pose, when the variable quantity of position has been more than pre-
If distance threshold and/or the variable quantity in orientation be more than preset angle threshold, then it is determined that the image information is key
Frame.
In ROVIO algorithm, i.e., when Vision Constraints relationship is that luminosity error (the luminosity error of characteristic point) is minimum, by step
Input of the posture information, motion information and road sign point obtained in 1011 as IMU motion model, to obtain IMU motion model
The prediction pose of output, road sign point are characterized a corresponding coordinate in local map.
For example, inputting the ROVIO state vector to be estimated for being can be χ=(r, v, q, bf,bw,c,z,μ0,…,
μM,ρ0,…,ρM), wherein r is coordinate of the IMU under global coordinate system, and v is speed of the IMU under global coordinate system, q IMU
Orientation under global coordinate system, bfFor the amount of bias of accelerometer, bwFor the amount of bias of gyroscope, c be image acquisition units with
The translational component joined outside IMU, z are the rotational component joined outside image acquisition units and IMU, μ0,…,μMIt is M characteristic point in image
Bearing vector, ρ under acquisition unit coordinate system0,…,ρMIt is inverse under image acquisition units coordinate system for M characteristic point
Depth parameter, inverse depth are the inverse of distance parameter.Using the output of IMU motion model as prediction pose, since IMU exists
Drift, therefore predict that pose is not accurate enough, further, according to the minimum Vision Constraints relationship of luminosity error, to prediction pose into
Row updates, and obtained pose is initial pose.
Fig. 4 is the flow chart of the SLAM method of another view-based access control model inertia shown according to an exemplary embodiment, such as
Shown in Fig. 4, step 103 includes:
Step 1031, when image information is key frame, according to initial pose, initial local map and before the first moment
The crucial posture information of preset quantity establish objective function, objective function includes the measurement residual sum image acquisition units of IMU
Measurement residual error, before crucial posture information was the first moment image acquisition units acquire history image information be key frame
When, the posture information for including in history image information can also include the information such as speed and amount of bias that IMU measurement obtains.
Step 1032, objective function is iterated according to preset algorithm, to obtain under the conditions of objective function is the smallest
Corresponding optimization pose and optimization local map.
For step 103, initial pose and initial local map are optimized, need to establish objective function come into
Row winding detection, to obtain optimization pose and optimization local map.Since nonlinear optimization algorithm calculating is slower, and in CPU
The occupancy deposited is higher, and therefore, the initial pose and initial local map that can be obtained to step 101 screen, just for
In the case that image information is key frame, just initial pose and initial local map are optimized, i.e. front end thread is in determination
When image information is key frame, initial pose and initial local map are just sent to rear end thread, determined by rear end thread excellent
Change pose and optimization local map.When image information is not key frame, it can be understood as the image information at the first moment with it is upper
Change between the image information at one moment less, without being optimized to initial pose and initial local map.Under normal conditions,
The time interval of the continuous key frame of two got in step 101 is long (such as 100ms), therefore reduces step
103 calculation amount, to further increase the computational efficiency and positioning accuracy of SLAM.
When image information is key frame, according to initial pose, initial local map and the present count before the first moment
The crucial posture information of amount establishes objective function.Wherein, objective function may include the measurement residual sum image acquisition units of IMU
Measurement residual error, such as: IMU pre-integration residual sum vision luminosity error etc..After selected target function, to objective function according to
Preset algorithm (such as: Gaussian-Newton method) is iterated, until objective function reaches optimum state, (i.e. objective function is most
It is small), the pose and local map that objective function determines at this time are to optimize pose and optimization local map.
Fig. 5 is the flow chart of the SLAM method of another view-based access control model inertia shown according to an exemplary embodiment, such as
Shown in Fig. 5, step 104 includes:
It step 1041, is optimization local map by target initial local map rejuvenation.
For example, local map optimization can be divided into step 104 and pose optimizes two parts, is existed for step 101
The target initial local map that second moment determined directly can substitute target initial local map with optimization local map, right
In the initial pose of target that step 101 determines at the second moment, and can be according in step 101 in expanded Kalman filtration algorithm
The difference of Vision Constraints is divided into two kinds of processing modes.
Step 1042, when Vision Constraints relationship is re-projection error minimum, by optimization pose and before the second moment
Preset quantity key posture information is merged according to Kalman filtering algorithm, and the initial pose of target is updated to Kalman
The pose of filtering algorithm output, the history image information that image acquisition units acquire before crucial posture information was the second moment are
When key frame, the posture information that includes in history image information.
For example, crucial using preset quantity of the Kalman filtering algorithm to optimization pose and before the second moment
When posture information is merged, it can be and merge Optimal State amount and Key state, wherein Optimal State amount includes
Optimize pose, can also include optimizing obtained speed and IMU amount of bias by step 103, Key state includes crucial position
Appearance information and corresponding speed and IMU amount of bias.Target original state amount is updated to Kalman filtering algorithm output later
Quantity of state, wherein target original state amount includes: the initial pose of target and corresponding speed and IMU amount of bias.
It further, may include: to use optimization locally for the update of the target original state amount at the second moment
It is residual that the quantity of state of figure, the second moment corresponding key frame and the N-1 key frame establishes vision back projection residual sum IMU pre-integration
Poor item carries out nonlinear iteration optimization (such as Gaussian-Newton method etc.), obtains the second moment high-precision quantity of state.With
Optimization in the step 103 of rear end is not required to optimization local map and the except that only optimize the quantity of state at the second moment here
The quantity of state of N-1 frame (because the two amounts are that rear end step 103 is fed back, accuracy is high).
Step 1043, it when Vision Constraints relationship is luminosity error minimum, obtains between initial pose and optimization pose
Offset.
Step 1044, according to offset more fresh target initial bit appearance.
Specifically, that is, Vision Constraints relationship is that re-projection error is minimum in MSCKF algorithm, pose and second will be optimized
The crucial posture information of preset quantity before moment is as Kalman filtering algorithm (English: Kalman Filtering, contracting
Write: KF) input obtain the pose of Kalman filtering algorithm output using state covariance matrix and process covariance matrix,
And the pose and covariance matrix for exporting the initial pose of target and corresponding covariance matrix update for Kalman filtering algorithm.
Wherein, the crucial posture information of the preset quantity before the second moment, it can be understood as pre-set the time of a sliding
Window, for N-1 crucial posture information before storing for the second moment.
In ROVIO algorithm, i.e., when Vision Constraints relationship is luminosity error minimum, it is corresponding can first to obtain for the first moment
Offset between initial pose and optimization pose, recycles the initial pose of offset correction target.Be t with the first moment,
Second moment was t+M to illustrate, offset Xdiff=tXbac*tX'fro, wherein the first moment, corresponding initial pose wastX'fro,
Optimizing pose istXbac.The so updated initial pose of targett+MX=Xdiff*t+MXfro, whereint+MXfroIt is corresponding for the second moment
Update before the initial pose of target.
Fig. 6 is the flow chart of the SLAM method of another view-based access control model inertia shown according to an exemplary embodiment, such as
Shown in Fig. 6, step 104 can also include:
Step 1045, updated target initial local map is stored in global map.
It further, can also by updated target initial local after to target initial local map rejuvenation
Figure deposit global map, i.e., the global map stored on more new terminal according to target initial local map.For example, can basis
The location information that target initial local map is included is referred to the location information in target initial local map substitution global map
The corresponding map in the region shown.
In conclusion image information and movement that the disclosure first acquires image acquisition units and IMU at the first moment
Information is merged according to expanded Kalman filtration algorithm, to obtain initial pose, is come further according to image information and initial pose
Initial local map is determined, later according to preset nonlinear optimization algorithm to the initial pose and the initial local map
It optimizes, to obtain optimization pose and optimization local map, finally according to the optimization pose and the optimization local map,
Update the initial pose of the second moment corresponding target and target initial local map.By by the defeated of expanded Kalman filtration algorithm
Out as the input of nonlinear optimization algorithm, and expanded Kalman filtration algorithm is corrected using the output of nonlinear optimization algorithm
Output, to improve the computational efficiency and positioning accuracy of SLAM.
Fig. 7 is a kind of block diagram of the SLAM device of view-based access control model inertia shown according to an exemplary embodiment, such as Fig. 7 institute
Show, which includes:
Fusion Module 201, image information and Inertial Measurement Unit IMU for acquiring the first moment image acquisition units
The motion information of acquisition is merged according to expanded Kalman filtration algorithm, to obtain initial pose.
Determining module 202, for determining initial local map according to image information and initial pose.
Optimization module 203, for being carried out according to preset nonlinear optimization algorithm to initial pose and initial local map
Optimization, to obtain optimization pose and optimization local map.
Update module 204, for according to optimization pose and optimization local map, more fresh target initial bit appearance and target to be initial
Local map, the initial pose of target are the movement letter of the image information for acquiring the second moment image acquisition units and IMU acquisition
Breath is merged according to expanded Kalman filtration algorithm, the initial pose of acquisition, when target initial local map is according to second
The initial local map that the image information and the initial pose of target for carving image acquisition units acquisition determine, the second moment was that acquisition is excellent
At the time of changing pose and optimization local map.
Fig. 8 is the block diagram of the SLAM device of another view-based access control model inertia shown according to an exemplary embodiment, such as Fig. 8
Shown, Fusion Module 201 includes:
Submodule 2011 is predicted, for regarding motion information and history pose as the input of IMU motion model, with acquisition
The prediction pose of IMU motion model output, history pose is the image information for acquiring third moment image acquisition units and IMU
The motion information of acquisition is merged according to expanded Kalman filtration algorithm, the initial pose of acquisition, when the third moment is first
At the time of before quarter.
Image procossing submodule 2012, for handling image information according to preset image processing algorithm, to obtain image
The Vision Constraints relationship for including in information.
Submodule 2013 is updated, for being updated according to Vision Constraints relationship to prediction pose, to obtain initial pose,
Vision Constraints relationship includes: that re-projection error is minimum or luminosity error is minimum.
Fig. 9 is the block diagram of the SLAM device of another view-based access control model inertia shown according to an exemplary embodiment, such as Fig. 9
Shown, determining module 202 includes:
Submodule 2021 is determined, for the pixel for meeting preset condition in image information to be determined as characteristic point.
Figure submodule 2022 is built, for carrying out three-dimensional reconstruction according to characteristic point and initial pose, with obtaining initial local
Figure.
Figure 10 is the block diagram of the SLAM device of another view-based access control model inertia shown according to an exemplary embodiment, is such as schemed
Shown in 10, optimization module 203 includes:
Setting up submodule 2031, for when image information is key frame, according to initial pose, initial local map and the
The crucial posture information of preset quantity before one moment establishes objective function, and objective function includes the measurement residual sum figure of IMU
As the measurement residual error of acquisition unit, the history image information that image acquisition units acquire before crucial posture information was the first moment
When for key frame, the posture information that includes in history image information.
Iteration submodule 2032, for being iterated according to preset algorithm to objective function, with obtain objective function most
Corresponding optimization pose and optimization local map under conditions of small.
Figure 11 is the block diagram of the SLAM device of another view-based access control model inertia shown according to an exemplary embodiment, is such as schemed
Shown in 11, update module 204 includes:
Map rejuvenation submodule 2041, for being optimization local map by target initial local map rejuvenation.
Pose update submodule 2042, for when Vision Constraints relationship be re-projection error minimum when, will optimization pose and
The crucial posture information of preset quantity before second moment is merged according to Kalman filtering algorithm, by target initial bit
Appearance is updated to the pose of Kalman filtering algorithm output, and image acquisition units acquire before crucial posture information was the second moment
The posture information for including when history image information is key frame, in history image information.
Pose updates submodule 2042, is also used to obtain initial pose when Vision Constraints relationship is luminosity error minimum
With the offset between optimization pose, and according to offset more fresh target initial bit appearance.
Further, map rejuvenation submodule 2041 can be also used for for updated target initial local map being stored in complete
Local figure.
About the device in above-described embodiment, wherein modules execute the concrete mode of operation in related this method
Embodiment in be described in detail, no detailed explanation will be given here.
In conclusion image information and movement that the disclosure first acquires image acquisition units and IMU at the first moment
Information is merged according to expanded Kalman filtration algorithm, to obtain initial pose, is come further according to image information and initial pose
Initial local map is determined, later according to preset nonlinear optimization algorithm to the initial pose and the initial local map
It optimizes, to obtain optimization pose and optimization local map, finally according to the optimization pose and the optimization local map,
Update the initial pose of the second moment corresponding target and target initial local map.By by the defeated of expanded Kalman filtration algorithm
Out as the input of nonlinear optimization algorithm, and expanded Kalman filtration algorithm is corrected using the output of nonlinear optimization algorithm
Output, to improve the computational efficiency and positioning accuracy of SLAM.
Figure 12 is the block diagram of a kind of electronic equipment 300 shown according to an exemplary embodiment.As shown in figure 12, the electronics
Equipment 300 may include: processor 301, memory 302.The electronic equipment 300 can also include multimedia component 303, defeated
Enter/export one or more of (I/O) interface 304 and communication component 305.
Wherein, processor 301 is used to control the integrated operation of the electronic equipment 300, used to complete above-mentioned view-based access control model
All or part of the steps in the SLAM method of property.Memory 302 is for storing various types of data to support in the electronics
The operation of equipment 300, these data for example may include any application program or side for operating on the electronic equipment 300
The instruction of method and the relevant data of application program, such as contact data, the message of transmitting-receiving, picture, audio, video etc..
The memory 302 can realize by any kind of volatibility or non-volatile memory device or their combination, such as quiet
State random access memory (Static Random Access Memory, abbreviation SRAM), the read-only storage of electrically erasable
Device (Electrically Erasable Programmable Read-Only Memory, abbreviation EEPROM), it is erasable to compile
Journey read-only memory (Erasable Programmable Read-Only Memory, abbreviation EPROM), may be programmed read-only storage
Device (Programmable Read-Only Memory, abbreviation PROM), and read-only memory (Read-Only Memory, referred to as
ROM), magnetic memory, flash memory, disk or CD.Multimedia component 303 may include screen and audio component.Wherein
Screen for example can be touch screen, and audio component is used for output and/or input audio signal.For example, audio component may include
One microphone, microphone is for receiving external audio signal.The received audio signal can be further stored in storage
Device 302 is sent by communication component 305.Audio component further includes at least one loudspeaker, is used for output audio signal.I/O
Interface 304 provides interface between processor 301 and other interface modules, other above-mentioned interface modules can be keyboard, mouse,
Button etc..These buttons can be virtual push button or entity button.Communication component 305 is for the electronic equipment 300 and other
Wired or wireless communication is carried out between equipment.Wireless communication, such as Wi-Fi, bluetooth, near-field communication (Near Field
Communication, abbreviation NFC), 2G, 3G or 4G or they one or more of combination, therefore corresponding communication
Component 305 may include: Wi-Fi module, bluetooth module, NFC module.
In one exemplary embodiment, electronic equipment 300 can be by one or more application specific integrated circuit
(Application Specific Integrated Circuit, abbreviation ASIC), digital signal processor (Digital
Signal Processor, abbreviation DSP), digital signal processing appts (Digital Signal Processing Device,
Abbreviation DSPD), programmable logic device (Programmable Logic Device, abbreviation PLD), field programmable gate array
(Field Programmable Gate Array, abbreviation FPGA), controller, microcontroller, microprocessor or other electronics member
Part is realized, for executing the SLAM method of above-mentioned view-based access control model inertia.
In a further exemplary embodiment, a kind of computer readable storage medium including program instruction is additionally provided, it should
The step of SLAM method of above-mentioned view-based access control model inertia is realized when program instruction is executed by processor.For example, the computer can
Reading storage medium can be the above-mentioned memory 302 including program instruction, and above procedure instruction can be by the processing of electronic equipment 300
Device 301 is executed to complete the SLAM method of above-mentioned view-based access control model inertia.
In conclusion image information and movement that the disclosure first acquires image acquisition units and IMU at the first moment
Information is merged according to expanded Kalman filtration algorithm, to obtain initial pose, is come further according to image information and initial pose
Initial local map is determined, later according to preset nonlinear optimization algorithm to the initial pose and the initial local map
It optimizes, to obtain optimization pose and optimization local map, finally according to the optimization pose and the optimization local map,
Update the initial pose of the second moment corresponding target and target initial local map.By by the defeated of expanded Kalman filtration algorithm
Out as the input of nonlinear optimization algorithm, and expanded Kalman filtration algorithm is corrected using the output of nonlinear optimization algorithm
Output, to improve the computational efficiency and positioning accuracy of SLAM.
The preferred embodiment of the disclosure is described in detail in conjunction with attached drawing above, still, the disclosure is not limited to above-mentioned reality
The detail in mode is applied, in the range of the technology design of the disclosure, a variety of letters can be carried out to the technical solution of the disclosure
Monotropic type, these simple variants belong to the protection scope of the disclosure.
It is further to note that specific technical features described in the above specific embodiments, in not lance
In the case where shield, can be combined in any appropriate way, in order to avoid unnecessary repetition, the disclosure to it is various can
No further explanation will be given for the combination of energy.
In addition, any combination can also be carried out between a variety of different embodiments of the disclosure, as long as it is without prejudice to originally
Disclosed thought equally should be considered as disclosure disclosure of that.