WO2017197617A1 - Movable three-dimensional laser scanning system and movable three-dimensional laser scanning method - Google Patents

Abstract

Provided is a movable three-dimensional laser scanning system, comprising: a movable scanning device (100) and a first signal processor (200). The movable scanning device (100) comprises a three-dimensional point cloud scanning instrument (120) and a sensing component (110). The three-dimensional point cloud scanning instrument (120) is used to perform three-dimensional scanning at different scanning locations and obtain corresponding point cloud data. The sensing component (110) is used to measure various parameters required by a simultaneous positioning and mapping algorithm. The first signal processor (200) is electrically connected to the three-dimensional point cloud scanning instrument (120) and the sensing component (110) respectively. The first signal processor (200) is used to update location and status information of a scanning center of the movable scanning device (100) in real time by means of the simultaneous positioning and mapping algorithm on the basis of data collected by the sensing component (110), and is further used to register point cloud data corresponding to any scanning center to a world coordinate system on the basis of real-time location and status information of the scanning center.

Description

Mobile three-dimensional laser scanning system and mobile three-dimensional laser scanning method Technical field

The invention relates to the field of three-dimensional laser scanning technology, in particular to a mobile three-dimensional laser scanning system and a mobile three-dimensional laser scanning method.

Background technique

The 3D laser scanner can be divided into a close range meter and a medium distance meter according to its application and measurement range. Its application range is wide, such as scenes in game development, interior design, measurement of vehicle parts design, accident site restoration, national cultural heritage protection, archaeological work and so on.

The data measured by the 3D laser scanner when scanning scene data once uses a scanning center as a reference point. Among them, the scanning center usually refers to the origin of the 3D laser scanner coordinate system. If in a large scene, multiple scans are required, and the data of multiple scans is subjected to data fusion processing, then the relative positional relationship between the plurality of scan centers, including position information and posture information, is also required. In the space, a certain registration method is required to register the position and posture information of multiple scanning centers.

However, in the traditional registration method, active registration is a manual input of the relative positional relationship (or manual dragging) of each scanning center, which is cumbersome and inefficient. Semi-automatic target registration is to calculate the relative positional relationship of each scanning center by scanning the same calibration device (calibration ball or other calibration device) multiple times. This operation is more complicated, and the positioning device has higher requirements for placement and efficiency. high.

Summary of the invention

Based on this, it is necessary to provide a highly efficient mobile 3D laser scanning system and a mobile 3D laser scanning method.

A mobile three-dimensional laser scanning system comprising:

a movable scanning device, comprising a three-dimensional point cloud scanning instrument and a sensing component; the three-dimensional point cloud scanning instrument is configured to perform three-dimensional scanning at different scanning positions and obtain corresponding point cloud data; the sensing component is used for measurement Simultaneous positioning and mapping parameters required for the mapping algorithm; and

a first signal processor electrically connected to the three-dimensional point cloud scanning instrument and the sensing component; the first signal processor is configured to use the data collected by the sensing component and utilize the simultaneous positioning and mapping The algorithm updates the position and posture information of the scan center of the movable scanning device in real time, and the first signal processor is further configured to use the real-time position and posture of the point cloud data corresponding to any scan center according to the scan center. The information is registered to the world coordinate system and is modeled in three dimensions based on the registered point cloud data.

A mobile three-dimensional laser scanning method, comprising:

Setting the initial position and posture information of the scan center of the movable scanning device;

Receiving initial point cloud data scanned by the 3D point cloud scanning instrument at the initial scanning position;

Registering the initial point cloud data into a world coordinate system according to the initial position and posture information;

Receiving, in the process of moving the movable scanning device to the next scanning position, data collected by the sensing component in real time, and updating the position and posture information by using a simultaneous positioning and mapping algorithm;

Receiving another set of point cloud data scanned by the three-dimensional point cloud scanning instrument at the next scanning position;

And registering the another set of point cloud data into the world coordinate system according to the position and posture information corresponding to the next scanning position;

Determining whether the movable scanning device is scanned, and if so, performing three-dimensional modeling according to the registered point cloud data corresponding to each scanning position; otherwise, performing the process of moving the movable scanning device to the next scanning position And receiving the data collected by the sensing component in real time and updating the position and posture information by using a simultaneous positioning and mapping algorithm.

A mobile three-dimensional laser scanning system comprising:

a movable scanning device, comprising a three-dimensional point cloud scanning instrument and a sensing component; the three-dimensional point cloud scanning instrument is configured to perform three-dimensional scanning at different scanning positions and obtain corresponding point cloud data; Sensing component is used to measure various parameters required for simultaneous positioning and mapping algorithms; and

a second signal processor electrically connected to the three-dimensional point cloud scanning instrument and the sensing component; the second signal processor is configured to use the data collected by the sensing component and utilize the simultaneous positioning and mapping The algorithm updates the position and posture information of the scan center of the movable scanning device in real time, and the first signal processor is further configured to use the real-time position and posture of the point cloud data corresponding to any scan center according to the scan center. The information is registered into the world coordinate system and the registered data is sent to a 3D modeling processor for 3D modeling.

A mobile three-dimensional laser scanning method, comprising:

Setting the initial position and posture information of the scan center of the movable scanning device;

Receiving initial point cloud data scanned by the 3D point cloud scanning instrument at the initial scanning position;

And initializing the initial point cloud data into a world coordinate system according to the initial position and posture information, and transmitting the registered point cloud data to a three-dimensional modeling processor for performing three-dimensional modeling;

Receiving, in the process of moving the movable scanning device to the next scanning position, data collected by the sensing component in real time, and updating the position and posture information by using a simultaneous positioning and mapping algorithm;

Receiving another set of point cloud data scanned by the three-dimensional point cloud data scanning instrument at the next scanning position;

And registering the another set of point cloud data into the world coordinate system according to the position and posture information corresponding to the next scanning position, and transmitting the registered point cloud data to the three-dimensional modeling processor ;

When it is determined that the movable scanning device has not been scanned, continue to perform the process of moving the movable scanning device to the next scanning position, receiving data collected by the sensing component in real time, and updating by using a simultaneous positioning and mapping algorithm. The step of position and posture information.

The above-mentioned mobile three-dimensional laser scanning system and the mobile three-dimensional laser scanning method have the beneficial effects of: a three-dimensional point cloud scanning instrument for performing three-dimensional scanning at different scanning positions and obtaining corresponding point cloud data. The first signal processor is configured to update the position and posture information of the scan center of the movable scanning device in real time according to the data collected by the sensing component and using a simultaneous positioning and mapping algorithm, and the first signal processor is further configured to use any scanning center Corresponding point cloud data according to the real-time bit of the scanning center The position and attitude information is registered to the world coordinate system. Therefore, the mobile three-dimensional laser scanning system and the mobile three-dimensional laser scanning method can automatically update the position and posture information of each scanning center while the scanning process is being performed, thereby realizing a fully automatic registration mode, improving efficiency, and operating. simple.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present invention, and those skilled in the art can obtain drawings of other embodiments according to the drawings without any creative work.

1 is a schematic structural diagram of a mobile three-dimensional laser scanning system according to an embodiment;

2 is a schematic view showing another structure of a mobile three-dimensional laser scanning system of the embodiment shown in FIG. 1;

3 is a schematic structural view of the mobile three-dimensional laser scanning system of FIG. 2;

4 is a flow chart of a mobile three-dimensional laser scanning method performed by the first signal processor in the embodiment shown in FIG. 1;

FIG. 5 is a schematic structural diagram of a mobile three-dimensional laser scanning system according to another embodiment; FIG.

Figure 6 is a flow chart of a mobile three-dimensional laser scanning method performed by a second signal processor in the embodiment of Figure 5.

detailed description

In order to facilitate the understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the understanding of the present disclosure will be more fully understood.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning meaning meaning The terminology used herein is for the purpose of describing the particular embodiments, Used in this article The term "and/or" includes any and all combinations of one or more of the associated listed items.

An embodiment provides a mobile three-dimensional laser scanning system. As shown in FIG. 1, the mobile three-dimensional laser scanning system includes a movable scanning device 100 and a first signal processor 200. The movable scanning device 100 is movable, and the movable scanning device 100 includes a sensing component 110 and a three-dimensional point cloud scanning instrument 120. In other embodiments, the first signal processor 200 can also be disposed in the removable scanning device 100 to follow the movable scanning device 100 for movement. At the same time, the three-dimensional point cloud scanning instrument 120 and the sensing component 110 are electrically connected to the first signal processor 200, respectively.

The three-dimensional point cloud scanning instrument 120 is used for three-dimensional scanning at different scanning positions and to obtain corresponding point cloud data. Since the movable scanning device 100 is capable of moving, it is possible to move to different scanning positions, each scanning position corresponding to one scanning center. Then, the scanning position of the movable scanning device 100 is different, the corresponding scanning center is different, and the point cloud data obtained by the scanning is different. Specifically, the three-dimensional point cloud scanning instrument 120 can be a three-dimensional laser scanner or other instrument capable of three-dimensional scanning. At the same time, the point cloud data that the three-dimensional point cloud scanning instrument 120 can scan can be 360 degrees*180 degree omnidirectional point cloud data in order to obtain accurate scene data.

The first signal processor 200 is configured to update the position and posture information of the scan center of the movable scanning device 100 in real time according to the data collected by the sensing component 110 and using a simultaneous positioning and mapping algorithm. Specifically, in the process of moving the scanning device 100 from the previous scanning position to the next scanning position, the sensing component 110 collects data in real time. At the same time, the first signal processor 200 updates the position and posture information of the scanning center of the movable scanning device 100 in real time according to the data collected by the sensing component 110, thereby ensuring that when the movable scanning device 100 moves to the next scanning position, the corresponding information can be obtained. The position and posture information of the center is scanned, so the first signal processor 200 can automatically register the position and posture information of the plurality of scanning centers. Among them, the principle of simultaneous positioning and mapping algorithm is: in an unfamiliar environment, the moving object uses its own loaded sensor to detect the surrounding environment and generate an environmental map, and determine its position in the environmental problem map.

At the same time, the first signal processor 200 is further configured to register the point cloud data corresponding to any scanning center according to the real-time position and posture information of the scanning center into the world coordinate system, and perform three-dimensional according to the registered point cloud data. Modeling. Wherein, the first signal processor 200 is used each time the registration is performed. The point cloud data, location and attitude information correspond to a corresponding scanning center. After the scanning is completed, the point cloud data in the world coordinate system corresponding to each scanning center can be obtained, so that the three-dimensional modeling can be performed according to the point cloud data. Among them, 3D modeling is a 3D modeling technology based on point cloud, which can be point cloud surface reconstruction technology and point cloud triangle mesh technology.

The sensing component 110 is used to measure various parameters required for the simultaneous positioning and mapping algorithms described above. Among them, the parameters required for the simultaneous positioning and mapping algorithm include various parameters related to the control quantity and the observation measurement. The control amount is control information in the motion model for controlling the relationship between the previous moment of the movable scanning device 100 and the current time pose. Specifically, the amount of control may include speed or angular velocity. The observation is a relative pose relationship between the environmental feature point and the current movable scanning device 100.

In summary, the above-mentioned mobile three-dimensional laser scanning system can automatically update the position and posture information of each scanning center while the scanning process is being performed, thereby realizing a fully automatic registration mode, improving efficiency, and being simple in operation.

Specifically, the first signal processor 200 updates the position and posture information of the scanning center of the movable scanning device 100 by using a simultaneous positioning and mapping algorithm based on unscented Kalman filtering (ie, UKF algorithm). Among them, the simultaneous positioning and mapping algorithm based on unscented Kalman filter, namely UFASTSLAM algorithm, is based on the framework of Fast SLAM (Simultaneous Localization And Mapping) algorithm, which will be EKF (Extended Kalman Filter). The filtering is replaced with unscented Kalman filtering, so that the accuracy of the algorithm is improved compared to the EKF filtering based FASTSLAM, thereby improving the accuracy of the first signal processor 200 for calculating the position and attitude information of the scanning center of the movable scanning device 100. The basic principles of the UFASTSLAM algorithm are described below.

First, the principle of Unscented Kalman filter algorithm is introduced. The execution flow is as follows.

Among them, in the first step, the UKF algorithm extracts 2n+1 sigma points (line 1) according to the mean X _t-1 and variance P _{t-1 of the} state variables of the previous moment, and then passes the Sigma point through the nonlinear motion equation (the first Line 2), predicting the mean value of the current time state variable based on the weight value of the Sigma point

And variance

(Lines 3 and 4). The second step is based on the predicted value obtained in the previous step.

Re-extract 2n+1 sigma points (line 5), and then find the Sigma point transformation of the nonlinear observation equation (line 6). Finally, the variance and mean of the observations can be obtained (lines 7, 8). . In the third step, the interaction covariance and the Kalman gain are calculated based on the results obtained above (lines 9, 10). In the fourth step, the mean and variance of the system state variables are updated according to the difference between the Kalman gain and the actual observations and the predicted observations (lines 11, 12).

Next, the working principle of the position and posture information of the scan center in real time by the first signal processor 200 in the present embodiment using the UFASTSLAM algorithm will be specifically described. In addition, the following principle of operation assumes that the control amount and attitude of the movable scanning device 100 remain unchanged during the time interval of (t-1, t) in an ideal state.

1. Location estimation and update of the removable scanning device 100

First, the position, the control amount, and the noise and observation thereof and the noise thereof at the previous moment (ie, time t-1) of the movable scanning device 100 are jointly added to the matrix of the position and variance of the movable scanning device 100, as shown in the following formula. Show:

Among them, the augmentation matrix

A matrix in which the position of the movable scanning device 100 at time t-1, the amount of control, and the dimension of the observation information are 9 × 1 is included. The amount of control and the observation are derived from the relevant data acquired by the sensing component 110 at time t-1. Augmented matrix

A matrix of 9×9 dimension including the position variance, control noise, and observed noise information of the movable scanning device 100. R _t represents control noise. Q _t represents the observed noise.

Then, according to equation (1), 2n+1 (n is the dimension of the mean vector, where n=9) sigma points are extracted near the mean point, so the extracted Sigma point set is as follows.

Furthermore, the Sigma points of these sigma points transformed by the nonlinear motion model can be obtained as shown below.

Where u _t is the amount of control that the sensing component 110 measures at time t. At this time, the mean value and the predicted value of the variance of the position of the movable scanning device 100 at time t can be calculated from the weights of the respective sigma points, as shown below.

among them,

For the mean weight of the Sigma point,

The mean weight for the Sigma point. Thereafter, the observed information, that is, the actual observation observed by the sensing component 110 at time t, is used to update the predicted value in the above equation, as shown below.

among them

Is the Sigma point through the nonlinear observation equation,

Is the predicted value of the observation,

The vector for the update. From this, the interactive covariance matrix and the Kalman gain can be found as shown below.

Further based on the Kalman gain and the true observed value z _t and the observed predicted value

The difference between the values updates the mean and variance of the position of the removable scanning device 100 as shown below.

The Sigma point set of equation (2) is updated by the above equation as shown below.

2. Estimation and update of the location of environmental feature points

First, a Sigma point set of three-dimensional environmental features is constructed based on the mean of the observations, as shown in the following equation.

among them

Is the mean of the nth environmental feature at time t-1,

It is the variance of the nth environmental feature at time t-1, and the rest of the parameters are as described above. Then these Sigma point sets can be obtained through nonlinear observation equations.

As follows.

Further, the predicted values of the observed mean and variance can be obtained as shown below.

Next, you can calculate the interaction covariance, the Kalman gain, and update the mean and variance of the environmental feature locations as shown below.

3. Calculate particle weights for resampling

First, we need to calculate the weight of each particle, the calculation formula is as follows.

among them

In order to reduce the phenomenon of particle depletion, it is also necessary to judge whether the effective particle number is lower than the threshold. If it is less than the threshold, the algorithm needs to resample, so that resampling can be avoided in each iteration.

The principle of resampling is that the prior probability at time t-1 can be approximated by particles with weights. After systematic observation and recalculation of weights, those with large weights can classify several new particles, while those with small weights will be discarded, so that a new set of particles can be obtained. These new particles are added to the random quantity to predict the state at time t, that is, the system state transition process. Finally, enter the system observation process again and predict the state of the next moment.

Then, based on the principle of the position estimation and update of the movable scanning device 100, the estimation and update of the environmental feature point position, and the calculation of the particle weight and the resampling process, the first signal processor 200 can perform the corresponding iteration according to the UFASTSLAM algorithm. The loop process updates the position and orientation information of the movable scanning device 100 in real time.

Specifically, as shown in FIG. 2, the first signal processor 200 includes a simultaneous positioning and mapping unit 210, a three-dimensional point cloud registration unit 220, and a three-dimensional modeling unit 230 that are sequentially connected. The simultaneous positioning and mapping unit is also connected to the sensing component 110. The three-dimensional point cloud registration unit 220 is also coupled to the three-dimensional point cloud scanning instrument 120.

The simultaneous positioning and mapping unit 210 receives the data collected by the sensing component 110 in real time. In addition, the simultaneous positioning and mapping unit 210 is configured to update the position and posture information of the scanning center of the movable scanning device 100 in real time according to the data collected by the sensing component 110 and using the simultaneous positioning and mapping algorithm. In this embodiment, the simultaneous positioning and mapping unit 210 uses the above-described unscented Kalman filter-based simultaneous positioning and mapping algorithm to update the position and posture information of the scanning center of the movable scanning device 100 in real time.

The three-dimensional point cloud registration unit 220 is configured to receive point cloud data scanned by the three-dimensional point cloud scanning instrument 120 at each scanning position. At the same time, the three-dimensional point cloud registration unit 220 is configured to register the point cloud data corresponding to any scanning center according to the real-time position and posture information of the scanning center into the world coordinate system, and send the registered data to the three-dimensional construction. Modular unit 230. Then, the point cloud data, position and attitude information used by the three-dimensional point cloud registration unit 220 for registration are corresponding to a corresponding one of the scanning centers.

The three-dimensional modeling unit 230 is configured to perform three-dimensional modeling according to the registered point cloud data sent by the three-dimensional point cloud registration unit 220. After the movable scanning device 100 moves to all the scanning positions and scans, the three-dimensional modeling unit 230 can perform three-dimensional modeling according to the registered point cloud data obtained by all the scanning centers.

Wherein, when the movable scanning device 100 moves to the next scanning position from the previous scanning position, the positioning and drawing unit 210 updates the position and posture information of the movable scanning device 100 in real time. After the movable scanning device 100 moves to the next scanning position, the positioning and drawing unit 210 simultaneously transmits the position and posture information corresponding to the next scanning position scanning center to the three-dimensional point cloud registration unit 220. At the same time, the three-dimensional point cloud scanning instrument 120 starts scanning, and sends the scanned point cloud data to the three-dimensional point cloud registration unit 220. The 3D point cloud registration unit 220 can then register the point cloud data according to the position and posture information, and send the registered point cloud data to the 3D modeling unit 230.

It should be noted that the simultaneous positioning and mapping unit 210, the three-dimensional point cloud registration unit 220, and the three-dimensional modeling unit 230 may be disposed on the movable scanning device 100 or may be disposed outside the movable scanning device 100.

It can be understood that the specific structure of the first signal processor 200 is not limited to the above one case. As long as the position and posture information of the scanning center of the movable scanning device 100 can be updated in real time, and the point cloud data is registered into the world coordinate system for three-dimensional modeling.

Specifically, as shown in FIG. 2, the movable scanning device 100 further includes a GPS module 130. The GPS module 130 is coupled to the first signal processor 200 and is used to measure an initial scan position of the movable scanning device 100. When the movable scanning device 100 is in the initial scanning position, the longitude and latitude data of the movable scanning device 100 can be collected by the GPS module 130, thereby facilitating the first signal processor 200 to set the initial position information of the scanning center, and then in the subsequent During the movement, the positional information of each scanning center is updated by calculating the relative displacement between the scanning centers based on the initial position information.

Meanwhile, the sensing component 110 includes an attitude sensor 111, a speed sensor 112, and a distance sensor 113. The attitude sensor 111 is used to measure the posture of the movable scanning device 100, and can be used in the motion model and the observation model of the above simultaneous positioning and mapping algorithm. The attitude sensor 111 can be an electronic compass or other type of attitude sensor.

The speed sensor 112 is used to measure the speed, angular velocity or angular acceleration of the movable scanning device 100, and can provide information on the amount of control in the positioning and mapping algorithms. Speed sensor 112 may include an encoder, an inertial measurement unit, or other type of sensor. Among them, the encoder can measure the speed of the movable scanning device 100. The inertial measurement unit can measure the triaxial angular velocity and the three-cycle angular acceleration of the movable scanning device 100.

The distance sensor 113 is horizontally placed for measuring the relative positional relationship between the surrounding environment features and the movable scanning device 100 within a range of 360 degrees, and can provide related information for simultaneous positioning and mapping measurement. The distance sensor 113 may be a two-dimensional laser radar, a camera based on TOF (Time of Flight) technology, or a three-dimensional laser radar.

It can be understood that the specific sensor type of the sensing component 110 is not limited to the above one, as long as the requirement that the first signal processor 200 update the position and posture information of the scanning center of the movable scanning device 100 in real time can be satisfied.

Specifically, as shown in FIG. 3, the movable scanning device 100 further includes a moving mechanism 140 and a supporting mechanism 150. The moving mechanism 140 is mounted on the bottom of the support mechanism 150 and used to drive the support. Mechanism 150 moves to each scanning position. The movement state of the movement mechanism 140 can be manually operated by the user, or can be moved from the line control movement structure 140 by a corresponding control mechanism. Specifically, the moving mechanism 140 can be a scroll wheel. The support mechanism 150 is configured to carry the related sensors in the three-dimensional point cloud scanning instrument 120 and the sensing component 110.

In the present embodiment, the three-dimensional point cloud scanning instrument 120 is mounted to the support mechanism 150. Specifically, the three-dimensional point cloud scanning instrument 120 is placed on top of the movable scanning device 100, that is, the three-dimensional point cloud scanning instrument 120 is placed on the top of the supporting mechanism 150, so that the three-dimensional point cloud scanning instrument 120 is free from obstructions, thereby being able to A full range of point cloud data.

The sensing assembly 110 is mounted to the moving mechanism 140 or the support mechanism 150. The encoder in the speed sensor 112 is mounted on the moving mechanism 140 to facilitate determining the speed of the movable scanning device 100 based on the rotational speed of the roller. Other sensors can be mounted to both the moving mechanism 140 and the support mechanism 150.

Therefore, in this embodiment, as long as the moving mechanism 140 is controlled, the movable scanning device 100 can be moved to each scanning position, and at the same time, the sensing component 110 and the first signal processor 200 can finally obtain the registration corresponding to each scanning position. After the point cloud data, the three-dimensional modeling is simple, easy to carry, fast and efficient.

It can be understood that the specific structure of the movable scanning device 100 is not limited to the above one case as long as the mobile three-dimensional laser scanning system can be operated normally.

Based on the above mobile three-dimensional laser scanning system, this embodiment also proposes a mobile three-dimensional laser scanning method. The execution steps of the first signal processor 200 include the following, as shown in FIG. 4 .

Step S110, setting the movable scanning device 100 to scan the initial position and posture information of the center.

The first signal processor 200 can obtain the initial longitude and latitude data of the initial scanning position P0 through the GPS module 130, thereby setting the initial position information of the scanning center, which is recorded as (Xp0, Yp0, Zp0). The first signal processor 200 can acquire the initial posture information of the scan center through the attitude sensor 111, and record it as (Ap0, Bp0, Cp0). At the same time, the three-dimensional point cloud scanning instrument 120 scans at the initial scanning position, and sends the initial point cloud data obtained after the scanning to the first signal. Processor 200.

Step S120: Receive initial point cloud data scanned by the three-dimensional point cloud scanning instrument 120 at the initial scanning position P0, and record it as M0.

Step S130: Register initial point cloud data into the world coordinate system according to the initial position and posture information.

The first signal processor 200 registers the initial point cloud data M0 into the world coordinate system according to the initial position information (Xp0, Yp0, Zp0) and the initial posture information (Ap0, Bp0, Cp0), and the registered data. Recorded as M0'.

Step S140: In the process of moving the movable scanning device 100 to the next scanning position P1, the data collected by the sensing component 110 is received in real time, and the position and posture information of the scanning center is updated by using the simultaneous positioning and mapping algorithm.

When the movable scanning device 100 moves to the next scanning position P1, the first signal processor 200 can timely calculate the position information (Xp1, Vp1, Zp1) and the posture information (Ap1, Bp1, of the scanning center of the scanning position P1). Cp1). At the same time, the three-dimensional point cloud scanning instrument 120 scans at the scanning position P1 to obtain another set of point cloud data M1 and transmits it to the first signal processor 200.

Specifically, the simultaneous positioning and mapping algorithm is a simultaneous positioning and mapping algorithm based on unscented Kalman filtering, namely the UFASTSLAM algorithm. The algorithm is based on the framework of Fast SLAM (Simultaneous Localization And Mapping) algorithm, which replaces EKF (Extended Kalman Filter) filtering with unscented Kalman filter, which is better than ASTF-based FASTSLAM. The accuracy of the algorithm is increased, thereby improving the accuracy with which the first signal processor 200 calculates the position and orientation information of the scanning center of the movable scanning device 100.

Step S150: Receive another set of point cloud data M1 scanned by the three-dimensional point cloud scanning instrument 120 at the next scanning position P1.

Step S160: Register another set of point cloud data M1 into the world coordinate system according to the position and posture information corresponding to the next scanning position P1.

The first signal processor 200 registers another set of point cloud data M1 into the world coordinate system according to the position information (Xp1, Vp1, Zp1) and the attitude information (Ap1, Bp1, Cp1). The data after the order is recorded as M1'.

In step S170, it is determined whether the removable scanning device 100 has finished scanning, and if so, step S180 is performed; otherwise, step S140 is continued.

Wherein, the movable scanning device 100 scans all the scanning positions and scans. Then, in the subsequent scanning positions P2, ..., Pn, the corresponding updated position information is (Xp2, Yp2, Zp2), ... (Xpn, Ypn, Zpn), and the posture information is (Ap2, Bp2, Cp2), ... (Apn, Bpn, Cpn), the three-dimensional point cloud scanning instrument 120 obtains point cloud data respectively M2, ... Mn, and the registered point cloud data are M2', ... Mn', respectively.

Step S180: Perform three-dimensional modeling according to the registered point cloud data corresponding to each scanning position.

The first signal processor 200 finally performs three-dimensional modeling according to the group of registered point cloud data M1, M2, . . . , Mn, thereby completing the reconstruction process of the scene data.

In summary, the above-mentioned mobile three-dimensional laser scanning method can automatically update the position and posture information of each scanning center while the scanning process is being performed, thereby realizing a fully automatic registration mode, improving efficiency, and being simple in operation.

It should be understood that although the various steps in the flowchart of FIG. 4 are sequentially displayed as indicated by the arrows, these steps are not necessarily performed in the order indicated by the arrows. Except as explicitly stated herein, the execution of these steps is not strictly limited, and may be performed in other sequences. Moreover, at least some of the steps in FIG. 4 may include a plurality of sub-steps or stages, which are not necessarily performed at the same time, but may be executed at different times, and the order of execution thereof is not necessarily This may be performed in sequence, but may be performed alternately or alternately with other steps or at least a portion of the sub-steps or stages of the other steps.

In another embodiment, as shown in FIG. 5, a mobile three-dimensional laser scanning system 300 is also provided. The mobile three-dimensional laser scanning system 300 is coupled to a three-dimensional modeling processor 400. At the same time, the three-dimensional modeling processor 400 is used for three-dimensional modeling according to data transmitted by the mobile three-dimensional laser scanning system 300.

The mobile 3D laser scanning system 300 includes a movable removable scanning device 310, and the movable scanning device 310 includes a 3D point cloud scanning instrument 312 and a sensing component 311. Mobile three The dimensional laser scanning system 300 also includes a second signal processor 320. The three-dimensional point cloud scanning instrument 312 and the sensing component 311 are electrically connected 320 to the second signal processor, respectively.

The three-dimensional point cloud scanning instrument 312 is configured to perform three-dimensional scanning at different scanning positions and obtain corresponding point cloud data.

The second signal processor 320 is configured to update the position and posture information of the scanning center of the movable scanning device 310 in real time according to the data collected by the sensing component 311 and using a simultaneous positioning and mapping algorithm, and the second signal processor 320 is further used for The point cloud data corresponding to any scan center is registered to the world coordinate system according to the real-time position and posture information of the scan center, and the registered data is sent to the three-dimensional modeling processor 400.

The sensing component 311 is configured to measure various parameters required for the simultaneous positioning and mapping algorithm.

It should be noted that, in this embodiment, the mobile three-dimensional laser scanning system 300 does not have the function of three-dimensional modeling, that is, the second signal processor 320 does not include a three-dimensional modeling unit, and the specific implementation principles of the remaining structures are The above embodiments are the same and will not be described again here.

Based on the mobile three-dimensional laser scanning system in another embodiment described above, a mobile three-dimensional laser scanning method is also provided. The execution step of the second signal processor 320 is as shown in FIG. 6.

Step S210: Set the movable scanning device 310 to scan the initial position and posture information of the center.

The second signal processor 320 can obtain the initial longitude and latitude data of the initial position P0 through the GPS module, thereby setting the initial position information of the scan center, and setting it as (Xp0, Yp0, Zp0). The second signal processor 320 can obtain the initial posture information of the scan center by using the attitude sensor, and set it as (Ap0, Bp0, Cp0). At the same time, the three-dimensional point cloud scanning instrument 312 starts scanning at the initial position, and transmits the initial point cloud data obtained after the scanning to the second signal processor 320.

Step S220: Receive initial point cloud data scanned by the three-dimensional point cloud scanning instrument 312 at the initial position P0, and set it to M0.

Step S230: Register initial point cloud data into the world coordinate system according to the initial position and posture information, and send the registered point cloud data to the three-dimensional modeling processor 400.

The second signal processor 320 registers the initial point cloud data M0 into the world coordinate system according to the initial position information (Xp0, Yp0, Zp0) and the initial posture information (Ap0, Bp0, Cp0). The registered data is recorded as M0'.

Step S240, in the process that the movable scanning device 310 moves to the next scanning position P1, the data collected by the sensing component 311 is received in real time, and the position and posture information of the scanning center is updated by using the simultaneous positioning and mapping algorithm.

Then, when the movable scanning device 310 moves to the next scanning position P1, the second signal processor 320 can calculate the position information (Xp1, Yp1, Zp1) and the posture information (Ap1, Bp1, Cp1) of the position in time. At the same time, the three-dimensional point cloud scanning instrument 312 starts scanning the other set of point cloud data M1 at the next scanning position P1 and sends it to the second signal processor 320.

Specifically, the simultaneous positioning and mapping algorithm is a simultaneous positioning and mapping algorithm based on unscented Kalman filtering, namely the UFASTSLAM algorithm. The algorithm is based on the framework of Fast SLAM (Simultaneous Localization And Mapping) algorithm, which replaces EKF (Extended Kalman Filter) filtering with unscented Kalman filter, which is better than ASTF-based FASTSLAM. The accuracy of the algorithm is increased, thereby improving the accuracy with which the first signal processor 200 calculates the position and orientation information of the scanning center of the movable scanning device 100.

Step S250, receiving another set of point cloud data M1 scanned by the three-dimensional point cloud scanning instrument 312 at the next scanning position P1.

Step S260: Register another set of point cloud data M1 into the world coordinate system according to the position and posture information corresponding to the next scanning position P1, and send the registered point cloud data to the three-dimensional modeling processor 400.

The second signal processor 320 registers another set of point cloud data M1 into the world coordinate system according to the position information (Xp1, Yp1, Zp1) and the posture information (Ap1, Bp1, Cp1), and the registered data. Recorded as M1'.

In step S270, it is determined whether the removable scanning device 310 has finished scanning, and if so, the execution is completed; otherwise, step S240 is continued.

In the subsequent scanning positions P2, ..., Pn, the corresponding updated position information is (Xp2, Yp2, Zp2), ... (Xpn, Ypn, Zpn), and the posture information is (Ap2, Bp2, Cp2), ... (Apn , Bpn, Cpn), the point cloud data obtained by the three-dimensional point cloud scanning instrument 312 is M2, ... Mn, respectively. The point cloud data after the order is M2', ... Mn'.

The removable scanning device 310 scans after all the scanning positions have been traversed. The final three-dimensional modeling processor 400 performs three-dimensional modeling according to all the registered point cloud data sent by the mobile three-dimensional laser scanning system 300, thereby completing the reconstruction process of the scene data.

In summary, the above-mentioned mobile three-dimensional laser scanning method can automatically update the position and posture information of each scanning center while the scanning process is being performed, thereby realizing a fully automatic registration mode, improving efficiency, and being simple in operation.

It should be understood that although the various steps in the flowchart of FIG. 6 are sequentially displayed as indicated by the arrows, these steps are not necessarily performed in the order indicated by the arrows. Except as explicitly stated herein, the execution of these steps is not strictly limited, and may be performed in other sequences. Moreover, at least some of the steps in FIG. 6 may include a plurality of sub-steps or stages, which are not necessarily performed at the same time, but may be executed at different times, and the order of execution thereof is not necessarily This may be performed in sequence, but may be performed alternately or alternately with other steps or at least a portion of the sub-steps or stages of the other steps.

The technical features of the above-described embodiments may be arbitrarily combined. For the sake of brevity of description, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction between the combinations of these technical features, All should be considered as the scope of this manual.

The above-described embodiments are merely illustrative of several embodiments of the present invention, and the description thereof is more specific and detailed, but is not to be construed as limiting the scope of the invention. It should be noted that a number of variations and modifications may be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, the scope of the invention should be determined by the appended claims.

Claims (18)

1. A mobile three-dimensional laser scanning system, comprising:

   a movable scanning device, comprising a three-dimensional point cloud scanning instrument and a sensing component; the three-dimensional point cloud scanning instrument is configured to perform three-dimensional scanning at different scanning positions and obtain corresponding point cloud data; the sensing component is used for measurement Simultaneous positioning and mapping parameters required for the mapping algorithm; and

   a first signal processor electrically connected to the three-dimensional point cloud scanning instrument and the sensing component; the first signal processor is configured to use the data collected by the sensing component and utilize the simultaneous positioning and mapping The algorithm updates the position and posture information of the scan center of the movable scanning device in real time, and the first signal processor is further configured to use the real-time position and posture of the point cloud data corresponding to any scan center according to the scan center. The information is registered to the world coordinate system and is modeled in three dimensions based on the registered point cloud data.
2. The mobile three-dimensional laser scanning system according to claim 1, wherein the first signal processor updates the position and posture of the scanning center of the movable scanning device by using a simultaneous positioning and mapping algorithm based on unscented Kalman filtering. information.
3. The mobile three-dimensional laser scanning system according to claim 1, wherein the first signal processor comprises:

   Simultaneously positioning and drawing unit connected to the sensing component; the simultaneous positioning and drawing unit is configured to update the movable scanning device in real time according to data collected by the sensing component and using the simultaneous positioning and mapping algorithm Scanning location and attitude information; and

   a three-dimensional point cloud registration unit is respectively connected to the simultaneous positioning and mapping unit and the three-dimensional point cloud scanning instrument; the three-dimensional point cloud registration unit is configured to use the point cloud data corresponding to any scanning center according to the scanning The center real-time position and attitude information is registered into the world coordinate system, and the registered data is sent to the three-dimensional modeling unit;

   a three-dimensional modeling unit is connected to the three-dimensional point cloud registration unit; the three-dimensional modeling unit is configured to perform three-dimensional modeling according to the registered point cloud data.
4. The mobile three-dimensional laser scanning system according to claim 1, wherein the movable scanning device further comprises a GPS module; the GPS module is connected to the first signal processor, And used to measure the initial scanning position of the movable scanning device.
5. The mobile three-dimensional laser scanning system according to claim 1, wherein the sensing component comprises an attitude sensor, a speed sensor, and a distance sensor.
6. The mobile three-dimensional laser scanning system according to claim 1, wherein the movable scanning device further comprises a moving mechanism and a supporting mechanism; the moving mechanism is mounted on the bottom of the supporting mechanism and is used to drive the support The mechanism moves to each of the scanning positions;

   The three-dimensional point cloud scanning instrument is mounted to the support mechanism; the sensing component is mounted to the moving mechanism or the support mechanism.
7. The mobile three-dimensional laser scanning system of claim 1 wherein said three-dimensional point cloud scanning instrument is placed on top of said movable scanning device.
8. A mobile three-dimensional laser scanning method, comprising:

   Setting the initial position and posture information of the scan center of the movable scanning device;

   Receiving initial point cloud data scanned by the 3D point cloud scanning instrument at the initial scanning position;

   Registering the initial point cloud data into a world coordinate system according to the initial position and posture information;

   Receiving, in the process of moving the movable scanning device to the next scanning position, data collected by the sensing component in real time, and updating the position and posture information by using a simultaneous positioning and mapping algorithm;

   Receiving another set of point cloud data scanned by the three-dimensional point cloud scanning instrument at the next scanning position;

   And registering the another set of point cloud data into the world coordinate system according to the position and posture information corresponding to the next scanning position;

   Determining whether the movable scanning device is scanned, and if so, performing three-dimensional modeling according to the registered point cloud data corresponding to each scanning position; otherwise, performing the process of moving the movable scanning device to the next scanning position And receiving the data collected by the sensing component in real time and updating the position and posture information by using a simultaneous positioning and mapping algorithm.
9. The mobile three-dimensional laser scanning method according to claim 8, wherein the simultaneous positioning and mapping algorithm is a simultaneous positioning and mapping algorithm based on unscented Kalman filtering.
10. A mobile three-dimensional laser scanning system, comprising:

    a movable scanning device, comprising a three-dimensional point cloud scanning instrument and a sensing component; the three-dimensional point cloud scanning instrument is configured to perform three-dimensional scanning at different scanning positions and obtain corresponding point cloud data; the sensing component is used for measurement Simultaneous positioning and mapping parameters required for the mapping algorithm; and

    a second signal processor electrically connected to the three-dimensional point cloud scanning instrument and the sensing component; the second signal processor is configured to use the data collected by the sensing component and utilize the simultaneous positioning and mapping The algorithm updates the position and posture information of the scan center of the movable scanning device in real time, and the first signal processor is further configured to use the real-time position and posture of the point cloud data corresponding to any scan center according to the scan center. The information is registered into the world coordinate system and the registered data is sent to a 3D modeling processor for 3D modeling.
11. The mobile three-dimensional laser scanning system according to claim 10, wherein the second signal processor updates the position and posture of the scanning center of the movable scanning device by using a simultaneous positioning and mapping algorithm based on unscented Kalman filtering. information.
12. The mobile three-dimensional laser scanning system according to claim 10, wherein the second signal processor comprises:

    Simultaneously positioning and drawing unit connected to the sensing component; the simultaneous positioning and drawing unit is configured to update the movable scanning device in real time according to data collected by the sensing component and using the simultaneous positioning and mapping algorithm Scanning location and attitude information; and

    a three-dimensional point cloud registration unit is respectively connected to the simultaneous positioning and mapping unit and the three-dimensional point cloud scanning instrument; the three-dimensional point cloud registration unit is configured to use the point cloud data corresponding to any scanning center according to the scanning The central real-time position and attitude information is registered into the world coordinate system and the registered data is sent to the three-dimensional modeling processor.
13. A mobile three-dimensional laser scanning system according to claim 10, wherein said movable scanning device further comprises a GPS module; said GPS module being coupled to said second signal processor and for measuring said movable Scan the initial scan position of the device.
14. The mobile three-dimensional laser scanning system according to claim 10, wherein the sensing component comprises an attitude sensor, a speed sensor, and a distance sensor.
15. The mobile three-dimensional laser scanning system according to claim 10, wherein the movable scanning device further comprises a moving mechanism and a supporting mechanism; the moving mechanism is mounted on the bottom of the supporting mechanism and is used to drive the support The mechanism moves to each of the scanning positions;

    The three-dimensional point cloud scanning instrument is mounted to the support mechanism; the sensing component is mounted to the moving mechanism or the support mechanism.
16. The mobile three-dimensional laser scanning system of claim 10 wherein said three-dimensional point cloud scanning instrument is placed on top of said movable scanning device.
17. A mobile three-dimensional laser scanning method, comprising:

    Setting the initial position and posture information of the scan center of the movable scanning device;

    Receiving initial point cloud data scanned by the three-dimensional point cloud data scanning instrument at the initial scanning position;

    And initializing the initial point cloud data into a world coordinate system according to the initial position and posture information, and transmitting the registered point cloud data to a three-dimensional modeling processor for performing three-dimensional modeling;

    Receiving, in the process of moving the movable scanning device to the next scanning position, data collected by the sensing component in real time, and updating the position and posture information by using a simultaneous positioning and mapping algorithm;

    Receiving another set of point cloud data scanned by the three-dimensional point cloud scanning instrument at the next scanning position;

    And registering the another set of point cloud data into the world coordinate system according to the position and posture information corresponding to the next scanning position, and transmitting the registered point cloud data to the three-dimensional modeling processor ;

    When it is determined that the movable scanning device has not been scanned, continue to perform the process of moving the movable scanning device to the next scanning position, receiving data collected by the sensing component in real time, and updating by using a simultaneous positioning and mapping algorithm. The step of position and posture information.
18. The mobile three-dimensional laser scanning method according to claim 17, wherein the simultaneous positioning and mapping algorithm is a simultaneous positioning and mapping algorithm based on unscented Kalman filtering.

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