CN116592791B - Shape measurement method, device, apparatus and storage medium - Google Patents
Shape measurement method, device, apparatus and storage medium Download PDFInfo
- Publication number
- CN116592791B CN116592791B CN202310870780.4A CN202310870780A CN116592791B CN 116592791 B CN116592791 B CN 116592791B CN 202310870780 A CN202310870780 A CN 202310870780A CN 116592791 B CN116592791 B CN 116592791B
- Authority
- CN
- China
- Prior art keywords
- angle
- angles
- obtaining
- shape
- shape measurement
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000691 measurement method Methods 0.000 title claims abstract description 37
- 238000003860 storage Methods 0.000 title claims abstract description 11
- 238000005259 measurement Methods 0.000 claims abstract description 73
- 238000000034 method Methods 0.000 claims abstract description 18
- 230000007246 mechanism Effects 0.000 claims description 95
- 230000006870 function Effects 0.000 claims description 6
- 238000012545 processing Methods 0.000 abstract description 9
- 230000008569 process Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 238000004891 communication Methods 0.000 description 5
- 230000008901 benefit Effects 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 238000004364 calculation method Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/002—Measuring arrangements characterised by the use of optical techniques for measuring two or more coordinates
Abstract
The application belongs to the technical field of data processing, and discloses a shape measurement method, a shape measurement device, shape measurement equipment and a storage medium; the method comprises the following steps: acquiring a relative included angle between each laser range finder and a zero reference line; acquiring angle information acquired by an encoder, and acquiring reference angles of a plurality of laser range finders according to the angle information and the relative included angles; when the number of the reference angles meets a preset condition, obtaining an angle set according to a plurality of reference angles; obtaining measurement distances corresponding to all angles in the angle set, and obtaining the shape of the measured object according to the measurement distances, the length of the laser range finder and the angle set; according to the application, the laser distance measuring instrument is continuously rotated to obtain the corresponding angle of the laser distance measuring instrument when measuring the distance, the laser distance measuring instrument collects the distances of the measured object at a plurality of different angles, and curve fitting is carried out according to the measured distances of the angles to obtain the shape of the measured object, so that the shape of the object can be accurately obtained through the low-cost laser distance measuring instrument and the encoder.
Description
Technical Field
The present application relates to the field of data processing technologies, and in particular, to a shape measurement method, apparatus, device, and storage medium.
Background
Currently, object shape measurement techniques mainly include two types of contact measurement and non-contact measurement. Non-contact measurement techniques include two types: visual photographing three-dimensional measurement and laser three-dimensional measurement. The photographic three-dimensional measurement system has the advantages of high measurement speed and high measurement density. The laser measuring system has the advantage of high measuring precision.
Vision measurement can be largely divided into: both passive and active measurement methods. Active measurement methods can be broadly divided into two categories: time-of-flight (TOF) laser measurements and structured light measurements. The TOF laser measurement method acquires the three-dimensional shape of an object by calculating the time of flight of light. Structured light measurement is the projection of coded light onto the object under test by a projector while the camera captures the reconstructed scene. The structured light measurement can meet the requirement of industrial production on precision. At present, many shape measurement requirements exist in the market, but in the process of measuring the shape of an object, the shape measurement cost of the structured light with high accuracy is too high to meet the requirement of shape measurement with low cost in the market.
The foregoing is provided merely for the purpose of facilitating understanding of the technical solutions of the present application and is not intended to represent an admission that the foregoing is prior art.
Disclosure of Invention
The application mainly aims to provide a shape measurement method, which aims to solve the technical problems that the manual measurement accuracy of the prior art with low cost is not high enough, the shape measurement cost of the structured light with high accuracy is too high, and the requirement of the shape measurement with low cost on the market cannot be met.
In order to achieve the above object, the present application provides a shape measurement method, which is applied to a shape measurement system, the shape measurement system includes an encoder, a plurality of laser rangefinders and a planar rotation mechanism, the laser rangefinder is fixedly connected to the periphery of the planar rotation mechanism, the encoder is fixedly connected to the interior of the planar rotation mechanism, and the encoder and the laser rangefinder can rotate along with the planar rotation mechanism;
the shape measurement method comprises the following steps:
acquiring the length of a laser range finder, determining a zero position datum line of the encoder, and acquiring a relative included angle between each laser range finder and the zero position datum line;
acquiring angle information acquired by the encoder when the plane rotating mechanism is in a rotating state, and acquiring reference angles of a plurality of laser range finders according to the angle information and the relative included angle;
when the number of the reference angles meets a preset condition, obtaining an angle set according to a plurality of reference angles;
and obtaining the measurement distance corresponding to each angle in the angle set, and obtaining the shape of the measured object according to the measurement distance, the length of the laser range finder and the angle set.
Optionally, when the plane rotation mechanism is in a rotation state, acquiring angle information acquired by an encoder, and obtaining reference angles of the plurality of laser range finders according to the angle information and the relative included angle, including:
when the plane rotating mechanism is in a rotating state, acquiring an offset angle of the encoder zero position datum line at the current moment;
and obtaining the reference angle of the laser range finder at the current moment according to the offset angle and the relative included angle between each laser range finder and the zero reference line.
Optionally, when the number of the reference angles meets a preset condition, obtaining an angle set according to a plurality of reference angles includes:
continuously rotating the plane rotating mechanism to obtain a plurality of reference angles, and judging whether the number of the angles of the reference angles is larger than a number threshold value;
when the number of the angles of the reference angles is larger than a number threshold, judging whether the angles of the reference angles meet an angle range threshold or not;
and when the angle of the reference angle meets the angle range threshold, obtaining an angle set according to the plurality of reference angles.
Optionally, the obtaining the measurement distance corresponding to each angle in the angle set, and obtaining the shape of the measured object according to the measurement distance, the length of the laser range finder and the angle set includes:
establishing a reference coordinate system by taking a zero position reference line of the encoder as an axis and taking the center of the plane rotation mechanism as an origin;
acquiring measurement distances measured by the laser range finders corresponding to all angles in the angle set;
adding the measured distance and the length of the laser range finder to obtain reference distances corresponding to all angles in the angle set;
determining a reference coordinate of the measured object in the reference coordinate system according to the reference distance and the reference angle by using a trigonometric function;
and obtaining the shape of the measured object according to a plurality of reference coordinates of the measured object in the reference coordinate system.
Optionally, the obtaining the shape of the measured object according to a plurality of reference coordinates of the measured object in the reference coordinate system includes:
obtaining a plane polynomial according to a plurality of reference coordinates of the measured object in the reference coordinate system;
and performing curve fitting on the plane polynomial to obtain a fitting result, and obtaining the shape of the measured object according to the fitting result.
Optionally, the shape measurement system further comprises a vertical movement mechanism for driving the planar rotation mechanism to move up and down perpendicular to the reference coordinate system;
the method for obtaining the measured distance corresponding to each angle in the angle set, after obtaining the shape of the measured object according to the measured distance, the length of the laser range finder and the angle set, further comprises:
when the plane rotating mechanism moves up and down through the vertical motion mechanism, acquiring reference coordinates at different vertical distances;
obtaining a three-dimensional coordinate set according to the reference coordinates of the plane rotating mechanism at different vertical distances;
and obtaining the three-dimensional shape of the measured object according to the three-dimensional coordinate set.
Optionally, the obtaining the three-dimensional shape of the measured object according to the three-dimensional coordinate set includes:
obtaining a plurality of three-dimensional space points according to the three-dimensional coordinate set;
performing surface fitting according to the three-dimensional space points to obtain a three-dimensional surface of the measured object;
and determining the three-dimensional shape of the object to be measured according to the three-dimensional curved surface.
In addition, in order to achieve the above object, the present application also proposes a shape measuring apparatus including:
the acquisition module is used for acquiring the length of the laser range finders, determining zero position datum lines of the encoder and acquiring the relative included angle between each laser range finders and the zero position datum lines;
the acquisition module is further used for acquiring angle information acquired by the encoder when the plane rotation mechanism is in a rotation state, and acquiring reference angles of a plurality of laser range finders according to the angle information and the relative included angle;
the acquisition module is further used for acquiring an angle set according to a plurality of reference angles when the number of the reference angles meets a preset condition;
and the measuring module is used for acquiring the measuring distance corresponding to each angle in the angle set, and obtaining the shape of the measured object according to the measuring distance, the length of the laser range finder and the angle set.
Furthermore, to achieve the above object, the present application also proposes a shape measurement apparatus including: a memory, a processor and a shape measurement program stored on the memory and executable on the processor, the shape measurement program configured to implement the steps of the shape measurement method as described above.
In addition, to achieve the above object, the present application also proposes a storage medium having stored thereon a shape measurement program which, when executed by a processor, implements the steps of the shape measurement method as described above.
According to the application, the laser distance measuring instrument is continuously rotated to obtain the corresponding angle of the laser distance measuring instrument when measuring the distance, the laser distance measuring instrument collects the distances of the measured object at a plurality of different angles, and curve fitting is carried out according to the measured distances of the angles to obtain the shape of the measured object, so that the shape of the object can be accurately obtained through the low-cost laser distance measuring instrument and the encoder.
Drawings
FIG. 1 is a schematic diagram of a shape measurement device of a hardware operating environment according to an embodiment of the present application;
FIG. 2 is a flow chart of a first embodiment of the shape measurement method of the present application;
FIG. 3 is a top view of a planar rotation mechanism and a laser rangefinder according to one embodiment of the shape measurement method of the application;
FIG. 4 is a flow chart of a second embodiment of the shape measurement method of the present application;
FIG. 5 is a schematic diagram of a shape measurement system according to an embodiment of the shape measurement method of the present application;
FIG. 6 is a schematic view showing a rotation state of a plane rotation mechanism according to an embodiment of the shape measurement method of the present application;
FIG. 7 is a schematic diagram showing a linear motion mechanism driving a planar rotation mechanism to move vertically according to an embodiment of the shape measurement method of the present application;
fig. 8 is a block diagram showing the structure of a first embodiment of the shape measuring apparatus of the present application.
The achievement of the objects, functional features and advantages of the present application will be further described with reference to the accompanying drawings, in conjunction with the embodiments.
Detailed Description
It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a shape measurement device in a hardware running environment according to an embodiment of the present application.
As shown in fig. 1, the shape measurement apparatus may include: a processor 1001, such as a central processing unit (Central Processing Unit, CPU), a communication bus 1002, a user interface 1003, a network interface 1004, a memory 1005. Wherein the communication bus 1002 is used to enable connected communication between these components. The user interface 1003 may include a Display, an input unit such as a Keyboard (Keyboard), and the optional user interface 1003 may further include a standard wired interface, a wireless interface. The network interface 1004 may optionally include a standard wired interface, a Wireless interface (e.g., a Wireless-Fidelity (Wi-Fi) interface). The Memory 1005 may be a high-speed random access Memory (Random Access Memory, RAM) Memory or a stable nonvolatile Memory (NVM), such as a disk Memory. The memory 1005 may also optionally be a storage device separate from the processor 1001 described above.
Those skilled in the art will appreciate that the configuration shown in fig. 1 is not limiting of the shape measurement device and may include more or fewer components than shown, or may combine certain components, or may be arranged in different components.
As shown in fig. 1, an operating system, a network communication module, a user interface module, and a shape measurement program may be included in the memory 1005 as one type of storage medium.
In the shape measurement device shown in fig. 1, the network interface 1004 is mainly used for data communication with a network server; the user interface 1003 is mainly used for data interaction with a user; the processor 1001 and the memory 1005 in the shape measurement apparatus of the present application may be provided in the shape measurement apparatus, which invokes the shape measurement program stored in the memory 1005 through the processor 1001 and performs the shape measurement method provided by the embodiment of the present application.
An embodiment of the present application provides a shape measurement method, referring to fig. 2, fig. 2 is a schematic flow chart of a first embodiment of the shape measurement method of the present application.
In this embodiment, the shape measurement method includes the following steps:
step S10: and acquiring the length of the laser range finders, determining a zero position datum line of the encoder, and acquiring the relative included angle between each laser range finders and the zero position datum line.
It should be noted that, the shape measurement method is applied to a shape measurement system, the shape measurement system includes an encoder, a plurality of laser rangefinder and a plane rotation mechanism, the laser rangefinder is fixedly connected to the periphery of the plane rotation mechanism, the encoder is fixedly connected to the inside of the plane rotation mechanism, and the encoder and the laser rangefinder can rotate along with the plane rotation mechanism.
It is understood that the laser range finder may be a commercially available distance measuring instrument using laser, and it is easy to know that the laser range finder body has a certain length, and the length of the laser range finder may be the length of the laser range finder body.
It should be understood that the encoder may be a device for obtaining angle information, and the encoder may be located inside the planar rotation mechanism and fixedly connected thereto. The periphery of the plane rotating mechanism is fixedly connected with a plurality of laser range finders.
The zero reference line of the encoder is one direction that the encoder initially collects before rotating. Referring to fig. 3 in detail, fig. 3 may be regarded as a top view of the plane rotation mechanism and the laser rangefinders, with two circles in the middle constituting the plane rotation mechanism, and 4 laser rangefinders fixedly connected outside the plane rotation mechanism. Referring to fig. 3, the plane rotation mechanism is in an initial static state at this time, and the direction of the encoder in the initial static state, that is, the direction of the encoder zero reference line in the figure, is acquired; further, h1-h4 in the figure respectively represent the body lengths of 4 laser rangefinders, and alpha 1-alpha 4 in the figure represent the relative angles between the 4 laser rangefinders and the encoder zero reference line.
It should be further noted that the relative angle between each laser range finder and the zero reference line can be acquired through an encoder, or can be input into the encoder after manual measurement, and is directly adopted when needed.
Step S20: and when the plane rotating mechanism is in a rotating state, acquiring angle information acquired by the encoder, and acquiring reference angles of a plurality of laser range finders according to the angle information and the relative included angle.
It is understood that the plane rotation mechanism may be a rotation mechanism that rotates in one horizontal plane, so that the plane shape of the object to be measured can be measured by the horizontal rotation mechanism.
It should be appreciated that the angular information collected by the encoder may include information corresponding to the rotated zero reference line.
It is understood that the reference angle may be an angle of each laser rangefinder relative to the initial encoder null reference line during rotation, and it should be noted that the angle indicated in this embodiment may be between 0 and 360 degrees.
It should be noted that, when the plane rotation mechanism is in a rotation state, the angle information collected by the encoder is obtained, and the reference angles of the plurality of laser rangefinders are obtained according to the angle information and the relative included angle, including: when the plane rotating mechanism is in a rotating state, acquiring an offset angle of the encoder zero position datum line at the current moment; and obtaining the reference angle of the laser range finder at the current moment according to the offset angle and the relative included angle between each laser range finder and the zero reference line.
It should be further noted that, because the laser rangefinder is fixedly connected with the plane rotation mechanism, and the encoder is also fixedly connected with the plane rotation mechanism, under the known relative included angle between the laser rangefinder and the encoder zero position datum line, the relative included angle is unchanged no matter how the laser rangefinder rotates, and according to the angle of the encoder zero position datum line relative to the initial zero position datum line after the encoder rotates when the encoder can obtain the rotation, the angle of each laser rangefinder relative to the initial zero position datum line can be further obtained.
Step S30: and when the number of the reference angles meets a preset condition, obtaining an angle set according to the plurality of reference angles.
It is understood that the preset condition includes the number of reference angles and the angular range of the reference angles.
It should be understood that when the number of reference angles satisfies the preset condition, all the reference angles are taken as an angle set, and if the number and the angle range of all the reference angles do not satisfy the preset condition, the rotating mechanism is continuously rotated, and new reference angles are continuously acquired until the reference angles satisfy the preset condition.
It should be noted that, when the number of the reference angles satisfies a preset condition, obtaining an angle set according to a plurality of reference angles includes:
continuously rotating the plane rotating mechanism to obtain a plurality of reference angles, judging whether the number of the angles of the reference angles is larger than a number threshold value, and obtaining the position of a certain point on the measured object through the reference angles and the measurement length of laser measurement, wherein if the number of the measured points is insufficient, the shape of the finally obtained measured object is inaccurate; in short, the more the angle of the laser measuring instrument on the plane rotation mechanism is, the more the number of points of the measured object is, and the more accurate the shape of the measured object is finally obtained according to the points of the measured object, so in order to obtain the more accurate shape of the measured object, the shape of the measured object needs to be obtained according to the reference angle when the number of the reference angles is greater than the threshold value.
When the number of the reference angles is larger than the number threshold, judging whether the angles of the reference angles meet the angle range threshold, wherein the rotation mechanism drives the laser measuring instrument to rotate to obtain a plurality of reference angles, however, all angles are between 0 and 360 degrees in the rotation process, and along with the continuous rotation, the reference angles obtained according to the laser distance measuring instrument may be repeated, if the number of the reference angles is enough, but the reference angles are repeated only in a plurality of areas, and the distances of the measured object at different angles cannot be comprehensively obtained. When the reference angle meets the angle range, the measured distances at different angles can be measured more comprehensively from a plurality of angles, and the more accurate shape of the measured object can be obtained further according to the measured distances at different angles.
And when the angle of the reference angle meets the angle range threshold, obtaining an angle set according to the plurality of reference angles.
Step S40: and obtaining the measurement distance corresponding to each angle in the angle set, and obtaining the shape of the measured object according to the measurement distance, the length of the laser range finder and the angle set.
It can be understood that in the process that the whole laser measuring instrument is driven to rotate by the rotating mechanism, the measuring distance of the laser measuring instrument is measured at each moment, the encoder can obtain the angle of each laser measuring instrument according to the changing angle of the zero position datum line at each moment relative to the initial zero position datum line and the changing angle and the relative angle of the zero position datum line at each moment.
It should be understood that the laser gauge is optionally mounted within the object, and the laser gauge may emit laser light to obtain the distance of a point of the measured object from the laser gauge, and to obtain the angle of the point from the initial zero reference line.
It should be noted that, according to the distance and angle of each point measured by the laser measuring instrument, the position of each point of the measured object in the reference coordinate system is established by taking the zero reference line of the encoder as an axis and taking the center of the plane rotation mechanism as an origin.
It should be further noted that, according to the measured distance, the length of the laser range finder and the angle set, the positions of the points of the measured object in the reference coordinate system may be obtained, the positions of the points of the measured object form a set of points, and the set of points may be subjected to curve fitting by a least square method, where the fitted curve is the shape of the measured object.
It can be understood that the rotating mechanism and the laser range finder in this embodiment may also perform measurement outside the measured object, a first coordinate system may be established with the measured object as an origin, a second coordinate system may be established with the rotating mechanism as the origin, the first coordinate system and the second coordinate system may be calibrated to obtain a conversion relationship between the first coordinate system and the second coordinate system, and then positions of points of the measured object in the second coordinate system may be measured at different positions outside the measured object by the rotating mechanism and the laser range finder.
Further, a plurality of coordinate systems can be built around the measured object, a rotating mechanism is placed at the origin of each coordinate system to measure the coordinates of different positions of the measured object, then coordinate points of the measured object in the coordinate systems are unified to the same coordinate system, finally, a position set of each point of the measured object in the same coordinate system is obtained, and curve fitting is carried out according to the position set of the measured object, so that the shape of the measured object is obtained.
According to the embodiment, the laser range finders are continuously rotated to obtain the angles corresponding to the laser range finders when measuring the distances, the laser range finders collect the distances of the measured object at a plurality of different angles, curve fitting is carried out according to the measured distances of the angles, and the shape of the measured object is obtained, so that the shape of the object is accurately obtained through the low-cost laser range finders and the encoder.
Referring to fig. 4, fig. 4 is a flowchart illustrating a shape measurement method according to a second embodiment of the present application.
Based on the first embodiment, the shape measurement method of the present embodiment includes, at the step S40:
step S41: and establishing a reference coordinate system by taking a zero position reference line of the encoder as an axis and taking the center of the plane rotation mechanism as an origin.
It is understood that the plane coordinate system may be formed by an origin, an x-axis and a y-axis, and the reference coordinate system in this embodiment is formed by taking the center of the rotation mechanism as the origin, taking the zero reference line of the encoder as the axis, and taking the zero reference line of the encoder as the x-axis or the y-axis, and then taking a straight line passing through the origin, being perpendicular to the zero reference line and being parallel to the ground as the other axis.
Step S42: and obtaining the measuring distance measured by the laser range finder corresponding to each angle in the angle set.
It is understood that the measurement distance here is the distance from the laser emission port of the laser rangefinder to the object to be measured.
Step S43: and adding the measured distance and the length of the laser range finder to obtain the reference distance corresponding to each angle in the angle set.
It can be understood that when the distance measurement is performed by the laser distance meter, the distance measured by the laser distance meter is obtained first, and the distance of the point of the measured object measured by the laser distance meter is obtained finally by adding the length of the laser distance meter after the measured distance is obtained by the central processing unit.
It should be understood that when the distance measurement is performed by the laser distance meter, the measured distance is the angle of the laser distance meter, and after the central processing unit receives the distance measured by the laser distance meter and adds the length of the laser distance meter, the central processing unit stores the distance measured by the laser distance meter in one-to-one correspondence with the angle of the laser distance meter at the moment, and each angle in the obtained angle set has a corresponding angle.
In a specific implementation, the shape measurement system may further include a processing unit, referring to fig. 5 in detail, where the rotation mechanism 1, the encoder 2, and the encoder 2 are connected to the rotation mechanism 1, so that the encoder 2 may read a current angle of the rotation mechanism 1, and the plurality of laser rangefinders 3, where the laser rangefinders 3 are fixed on the rotation mechanism and may rotate along with the rotation mechanism 1, and the processing unit 4 may receive real-time position feedback of the encoder 2, and may receive measured distance feedback of the laser rangefinders 3 at the same time.
It should be noted that, measurement accuracy and speed are related to parameters such as rotation speed of a rotating mechanism, sampling time of a laser range finder, installation number of the laser range finder, etc., wherein the shorter the sampling time is, the faster the rotation speed is, the more the installation number is, the more points are collected in the same time, the more accurate the collection is, and conversely, the shorter the time required for collecting the same point is, the faster the collection speed is.
Step S44: and determining the reference coordinates of the measured object in the reference coordinate system through the trigonometric function on the reference distance and the reference angle.
It is understood that in the reference coordinate system, a straight line is formed by connecting a point of the measured object measured by the laser range finder and an origin of the reference coordinate system, the reference distance is a straight line distance from the point to the origin, and the reference angle is an included angle between an axis formed by the straight line and a zero reference line.
It should be understood that the angle based on the included angle and the reference distance may be calculated by trigonometric function or Pythagorean theorem to obtain the abscissa and the ordinate of the point of the measured object in the reference coordinate system, wherein the reference coordinate is composed of the abscissa and the ordinate.
In a specific implementation, during measurement, the rotation mechanism starts to rotate, an encoder angle is acquired at any time T and recorded as θ, and reference may be made to fig. 6 in detail, and at the same time, distances from a measuring surface of the N laser rangefinder to a position of a contour to be measured are l1, l2, and … … lN, where a point measured on the contour to be measured by the N laser rangefinder can be calculated according to a trigonometric function, and a plane coordinate of a cartesian rectangular coordinate system established with a zero position of the encoder as an x-axis positive direction is:
wherein, in brief, l n Indicating the distance measured by each laser range finder, h n Representing the length of each laser range finder, alpha n And the included angle between each laser range finder and the zero reference line is represented. Reference is made in detail to fig. 6.
From this, the set of plane points measured when the encoder angle was noted θ was calculated to be (x 1, y 1), (x 2, y 2), … … (x N ,y N )。
Step S45: and obtaining the shape of the measured object according to a plurality of reference coordinates of the measured object in the reference coordinate system.
It will be appreciated that knowing the coordinates of the individual points that make up the shape of the object under test in the coordinate system, the exact shape of the object under test can be obtained by curve fitting the points that make up the shape of the object under test.
It should be noted that the obtaining the shape of the measured object according to the plurality of reference coordinates of the measured object in the reference coordinate system includes: obtaining a plane polynomial according to a plurality of reference coordinates of the measured object in the reference coordinate system; and performing curve fitting on the plane polynomial to obtain a fitting result, and obtaining the shape of the measured object according to the fitting result.
In a specific implementation, the plane point sets (x 1, y 1), (x 2, y 2), … … (xN, yN) are set, and the following polynomials can be used:
fitting is performed wherein the calculation matrix for calculating the coefficients a0, a1, a2,..ak is:
the values of the coefficients in the polynomials can be obtained through calculation of the matrix, the values of the coefficients are substituted into the original polynomials, the polynomials after the values of the coefficients are substituted can be obtained and displayed in the three-dimensional image, and the shape of the measured object can be obtained.
It is emphasized that the shape measurement system further comprises a vertical movement mechanism for driving the planar rotation mechanism to move up and down perpendicular to the reference coordinate system.
It is further emphasized that reference coordinates at different vertical distances are acquired as the planar rotation mechanism moves up and down by the vertical movement mechanism; obtaining a three-dimensional coordinate set according to the reference coordinates of the plane rotating mechanism at different vertical distances; and obtaining the three-dimensional shape of the measured object according to the three-dimensional coordinate set.
It can be understood that the three-dimensional shape of the measured object can be obtained by a three-dimensional coordinate set or by performing surface fitting by a least square method.
It should be further noted that the obtaining the three-dimensional shape of the measured object according to the three-dimensional coordinate set includes: obtaining a plurality of three-dimensional space points according to the three-dimensional coordinate set; performing surface fitting according to the three-dimensional space points to obtain a three-dimensional surface of the measured object; and determining the three-dimensional shape of the object to be measured according to the three-dimensional curved surface.
It should be noted that, the structure of the vertical movement mechanism may refer to fig. 7, in which 1 is a laser range finder, 2 is a rotation mechanism, 3 is a linear movement mechanism, the rotation mechanism can move back and forth along the linear mechanism under the condition of being rotatable, the movement direction is perpendicular to the rotation plane, and an encoder is mounted on the linear mechanism, so that the current position moved can be read. Thus, each plane point (x, y) calculated according to the previous plane ranging formula is required to be recorded and the position z of the linear mechanism when the point is read is added at the time of recording and is recorded as a three-dimensional space point (x, y, z), and thus the three-dimensional shape to be measured is generated according to the generated three-dimensional point set fitting.
According to the embodiment, the encoder zero line is taken as an axis, the center of the rotating mechanism is taken as an origin, the rotating mechanism is continuously rotated to drive the laser measuring instrument fixedly connected with the rotating mechanism to rotate, the positions of points of the measured object at different angles in the reference coordinate system are measured through the rotating laser measuring instrument, the reference coordinates of a plurality of points of the measured object in the reference coordinate system can be obtained through angle information obtained through the laser measuring instrument and the encoder, then the reference coordinates are fitted through a preset algorithm, the shape of the measured object can be obtained, the more the collected angles are, the larger the angle range is, and the more accurate the finally fitted shape is.
In addition, the embodiment of the application also provides a storage medium, wherein the storage medium stores a shape measurement program, and the shape measurement program realizes the steps of the shape measurement method when being executed by a processor.
Referring to fig. 8, fig. 8 is a block diagram showing the configuration of a first embodiment of the shape measuring apparatus of the present application.
As shown in fig. 8, a shape measurement apparatus according to an embodiment of the present application includes:
the acquisition module 10 is used for acquiring the length of the laser range finders, determining zero position datum lines of the encoder and acquiring the relative included angle between each laser range finders and the zero position datum lines;
the acquiring module 10 is further configured to acquire angle information acquired by the encoder when the plane rotation mechanism is in a rotation state, and obtain reference angles of the plurality of laser rangefinders according to the angle information and the relative included angle;
the obtaining module 10 is further configured to obtain an angle set according to a plurality of reference angles when the number of reference angles meets a preset condition;
and the measurement module 20 is configured to obtain measurement distances corresponding to angles in the angle set, and obtain a shape of the measured object according to the measurement distances, the length of the laser range finder, and the angle set.
According to the embodiment, the laser range finders are continuously rotated to obtain the angles corresponding to the laser range finders when measuring the distances, the laser range finders collect the distances of the measured object at a plurality of different angles, curve fitting is carried out according to the measured distances of the angles, and the shape of the measured object is obtained, so that the shape of the object is accurately obtained through the low-cost laser range finders and the encoder.
In an embodiment, the obtaining module 10 is further configured to obtain, when the plane rotation mechanism is in a rotation state, an offset angle of the encoder zero reference line at a current time;
and obtaining the reference angle of the laser range finder at the current moment according to the offset angle and the relative included angle between each laser range finder and the zero reference line.
In an embodiment, the obtaining module 10 is further configured to continuously rotate the plane rotation mechanism to obtain a plurality of reference angles, and determine whether the number of angles of the reference angles is greater than a number threshold;
when the number of the angles of the reference angles is larger than a number threshold, judging whether the angles of the reference angles meet an angle range threshold or not;
and when the angle of the reference angle meets the angle range threshold, obtaining an angle set according to the plurality of reference angles.
In an embodiment, the measurement module 20 is further configured to establish a reference coordinate system with a zero reference line of the encoder as an axis and a center of the planar rotation mechanism as an origin;
acquiring measurement distances measured by the laser range finders corresponding to all angles in the angle set;
adding the measured distance and the length of the laser range finder to obtain reference distances corresponding to all angles in the angle set;
determining a reference coordinate of the measured object in the reference coordinate system according to the reference distance and the reference angle by using a trigonometric function;
and obtaining the shape of the measured object according to a plurality of reference coordinates of the measured object in the reference coordinate system.
In an embodiment, the measurement module 20 is further configured to obtain a plane polynomial according to a plurality of reference coordinates of the measured object in the reference coordinate system;
and performing curve fitting on the plane polynomial to obtain a fitting result, and obtaining the shape of the measured object according to the fitting result.
In one embodiment, the measuring module 20 is further configured to collect reference coordinates at different vertical distances when the plane rotation mechanism moves up and down through the vertical movement mechanism;
obtaining a three-dimensional coordinate set according to the reference coordinates of the plane rotating mechanism at different vertical distances;
and obtaining the three-dimensional shape of the measured object according to the three-dimensional coordinate set.
In an embodiment, the measurement module 20 is further configured to obtain a plurality of three-dimensional space points according to the three-dimensional coordinate set;
performing surface fitting according to the three-dimensional space points to obtain a three-dimensional surface of the measured object;
and determining the three-dimensional shape of the object to be measured according to the three-dimensional curved surface.
It should be understood that the foregoing is illustrative only and is not limiting, and that in specific applications, those skilled in the art may set the application as desired, and the application is not limited thereto.
It should be noted that the above-described working procedure is merely illustrative, and does not limit the scope of the present application, and in practical application, a person skilled in the art may select part or all of them according to actual needs to achieve the purpose of the embodiment, which is not limited herein.
Furthermore, it should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.
The foregoing embodiment numbers of the present application are merely for the purpose of description, and do not represent the advantages or disadvantages of the embodiments.
From the above description of embodiments, it will be clear to a person skilled in the art that the above embodiment method may be implemented by means of software plus a necessary general hardware platform, but may of course also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. Read Only Memory (ROM)/RAM, magnetic disk, optical disk) and comprising several instructions for causing a terminal device (which may be a mobile phone, a computer, a server, or a network device, etc.) to perform the method according to the embodiments of the present application.
It should be understood that, although the steps in the flowcharts in the embodiments of the present application are shown in order as indicated by the arrows, these steps are not necessarily performed in order as indicated by the arrows. The steps are not strictly limited in order and may be performed in other orders, unless explicitly stated herein. Moreover, at least some of the steps in the figures may include multiple sub-steps or stages that are not necessarily performed at the same time, but may be performed at different times, the order of their execution not necessarily occurring in sequence, but may be performed alternately or alternately with other steps or at least a portion of the other steps or stages.
The foregoing description is only of the preferred embodiments of the present application, and is not intended to limit the scope of the application, but rather is intended to cover any equivalents of the structures or equivalent processes disclosed herein or in the alternative, which may be employed directly or indirectly in other related arts.
Claims (9)
1. The shape measurement method is characterized by being applied to a shape measurement system, wherein the shape measurement system comprises an encoder, a plurality of laser rangefinders and a plane rotation mechanism, the laser rangefinder is fixedly connected to the periphery of the plane rotation mechanism, the encoder is fixedly connected to the inside of the plane rotation mechanism, and the encoder and the laser rangefinder can rotate along with the plane rotation mechanism;
the shape measurement method comprises the following steps:
acquiring the length of a laser range finder, determining a zero position datum line of the encoder, and acquiring a relative included angle between each laser range finder and the zero position datum line;
acquiring angle information acquired by the encoder when the plane rotating mechanism is in a rotating state, and acquiring reference angles of a plurality of laser range finders according to the angle information and the relative included angle;
when the number of the reference angles meets a preset condition, obtaining an angle set according to a plurality of reference angles;
obtaining measurement distances corresponding to all angles in the angle set, and obtaining the shape of the measured object according to the measurement distances, the length of the laser range finder and the angle set;
and when the number of the reference angles meets a preset condition, obtaining an angle set according to a plurality of reference angles, wherein the angle set comprises:
continuously rotating the plane rotating mechanism to obtain a plurality of reference angles, and judging whether the number of the angles of the reference angles is larger than a number threshold value;
when the number of the angles of the reference angles is larger than a number threshold, judging whether the angles of the reference angles meet an angle range threshold or not;
and when the angle of the reference angle meets the angle range threshold, obtaining an angle set according to the plurality of reference angles.
2. The shape measurement method according to claim 1, wherein the obtaining the angle information collected by the encoder when the plane rotation mechanism is in a rotation state, and obtaining the reference angles of the plurality of laser rangefinders according to the angle information and the relative angle, comprises:
when the plane rotating mechanism is in a rotating state, acquiring an offset angle of the encoder zero position datum line at the current moment;
and obtaining the reference angle of the laser range finder at the current moment according to the offset angle and the relative included angle between each laser range finder and the zero reference line.
3. The shape measurement method according to claim 1, wherein the obtaining the measurement distance corresponding to each angle in the angle set, and obtaining the shape of the measured object according to the measurement distance, the length of the laser range finder, and the angle set, includes:
establishing a reference coordinate system by taking a zero position reference line of the encoder as an axis and taking the center of the plane rotation mechanism as an origin;
acquiring measurement distances measured by the laser range finders corresponding to all angles in the angle set;
adding the measured distance and the length of the laser range finder to obtain reference distances corresponding to all angles in the angle set;
determining a reference coordinate of the measured object in the reference coordinate system according to the reference distance and the reference angle by using a trigonometric function;
and obtaining the shape of the measured object according to a plurality of reference coordinates of the measured object in the reference coordinate system.
4. A shape measurement method according to claim 3, wherein the obtaining the shape of the object from a plurality of reference coordinates of the object in the reference coordinate system includes:
obtaining a plane polynomial according to a plurality of reference coordinates of the measured object in the reference coordinate system;
and performing curve fitting on the plane polynomial to obtain a fitting result, and obtaining the shape of the measured object according to the fitting result.
5. A shape measurement method according to claim 3, wherein the shape measurement system further comprises a vertical movement mechanism for driving the planar rotation mechanism to move up and down perpendicular to the reference coordinate system;
the method for obtaining the measured distance corresponding to each angle in the angle set, after obtaining the shape of the measured object according to the measured distance, the length of the laser range finder and the angle set, further comprises:
when the plane rotating mechanism moves up and down through the vertical motion mechanism, acquiring reference coordinates at different vertical distances;
obtaining a three-dimensional coordinate set according to the reference coordinates of the plane rotating mechanism at different vertical distances;
and obtaining the three-dimensional shape of the measured object according to the three-dimensional coordinate set.
6. The shape measurement method according to claim 5, wherein the obtaining the three-dimensional shape of the object to be measured from the three-dimensional coordinate set includes:
obtaining a plurality of three-dimensional space points according to the three-dimensional coordinate set;
performing surface fitting according to the three-dimensional space points to obtain a three-dimensional surface of the measured object;
and determining the three-dimensional shape of the object to be measured according to the three-dimensional curved surface.
7. A shape measurement device, the shape measurement device comprising:
the acquisition module is used for acquiring the length of the laser range finders, determining zero position datum lines of the encoder and acquiring the relative included angle between each laser range finders and the zero position datum lines;
the acquisition module is further used for acquiring angle information acquired by the encoder when the plane rotation mechanism is in a rotation state, and acquiring reference angles of a plurality of laser range finders according to the angle information and the relative included angle;
the acquisition module is further used for acquiring an angle set according to a plurality of reference angles when the number of the reference angles meets a preset condition;
the measuring module is used for obtaining measuring distances corresponding to all angles in the angle set and obtaining the shape of the measured object according to the measuring distances, the length of the laser range finder and the angle set;
the plane rotation mechanism is used for rotating the plane rotation mechanism continuously to obtain a plurality of reference angles, and judging whether the number of the angles of the reference angles is larger than a number threshold value or not; when the number of the angles of the reference angles is larger than a number threshold, judging whether the angles of the reference angles meet an angle range threshold or not; and when the angle of the reference angle meets the angle range threshold, obtaining an angle set according to the plurality of reference angles.
8. A shape measurement device, the device comprising: a memory, a processor, and a shape measurement program stored on the memory and executable on the processor, the shape measurement program configured to implement the shape measurement method of any one of claims 1 to 6.
9. A storage medium having a shape measurement program stored thereon, which when executed by a processor, implements the shape measurement method according to any one of claims 1 to 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310870780.4A CN116592791B (en) | 2023-07-17 | 2023-07-17 | Shape measurement method, device, apparatus and storage medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310870780.4A CN116592791B (en) | 2023-07-17 | 2023-07-17 | Shape measurement method, device, apparatus and storage medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116592791A CN116592791A (en) | 2023-08-15 |
| CN116592791B true CN116592791B (en) | 2023-10-03 |
Family
ID=87608364
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310870780.4A Active CN116592791B (en) | 2023-07-17 | 2023-07-17 | Shape measurement method, device, apparatus and storage medium |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116592791B (en) |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003207318A (en) * | 2002-01-16 | 2003-07-25 | Sumitomo Electric Ind Ltd | Method and device for measuring drill sectional shape |
| JP2005233906A (en) * | 2004-02-23 | 2005-09-02 | Bridgestone Corp | Surface inspecting device for rotating body |
| JP2007225342A (en) * | 2006-02-21 | 2007-09-06 | Toyota Motor Corp | Three-dimensional measuring device and autonomously moving device provided with three-dimensional measuring device |
| CN101187547A (en) * | 2007-12-04 | 2008-05-28 | 武汉理工大学 | Oil tank measuring device and measuring method |
| CN101493526A (en) * | 2008-11-28 | 2009-07-29 | 北京工业大学 | Lunar vehicle high speed three-dimensional laser imaging radar system and imaging method |
| CN101619965A (en) * | 2009-08-14 | 2010-01-06 | 北京领邦仪器技术有限公司 | Wheel-pair automatic measuring device |
| EP2698600A1 (en) * | 2012-08-16 | 2014-02-19 | Leica Geosystems AG | Distance measuring module |
| CN108344379A (en) * | 2018-01-23 | 2018-07-31 | 上海大学 | A kind of system and method measuring insulator cross-section profile shape and creepage distance |
| CN109238162A (en) * | 2018-09-25 | 2019-01-18 | 浙江科技学院 | A kind of tunnel 3 d deformation monitoring and method for early warning |
| CN110050200A (en) * | 2016-11-10 | 2019-07-23 | 莱卡地球系统公开股份有限公司 | Laser scanner |
| CN211043671U (en) * | 2019-09-25 | 2020-07-17 | 武汉海云空间信息技术有限公司 | Synchronous controller module for laser radar and laser radar |
| CN113847898A (en) * | 2021-09-24 | 2021-12-28 | 云南农业大学 | Multipoint distributed rail profile on-line detection device |
| CN114166147A (en) * | 2021-12-16 | 2022-03-11 | 上海应用技术大学 | Portable detector and method for steel rail profile based on three-dimensional laser scanning technology |
-
2023
- 2023-07-17 CN CN202310870780.4A patent/CN116592791B/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003207318A (en) * | 2002-01-16 | 2003-07-25 | Sumitomo Electric Ind Ltd | Method and device for measuring drill sectional shape |
| JP2005233906A (en) * | 2004-02-23 | 2005-09-02 | Bridgestone Corp | Surface inspecting device for rotating body |
| JP2007225342A (en) * | 2006-02-21 | 2007-09-06 | Toyota Motor Corp | Three-dimensional measuring device and autonomously moving device provided with three-dimensional measuring device |
| CN101187547A (en) * | 2007-12-04 | 2008-05-28 | 武汉理工大学 | Oil tank measuring device and measuring method |
| CN101493526A (en) * | 2008-11-28 | 2009-07-29 | 北京工业大学 | Lunar vehicle high speed three-dimensional laser imaging radar system and imaging method |
| CN101619965A (en) * | 2009-08-14 | 2010-01-06 | 北京领邦仪器技术有限公司 | Wheel-pair automatic measuring device |
| EP2698600A1 (en) * | 2012-08-16 | 2014-02-19 | Leica Geosystems AG | Distance measuring module |
| CN110050200A (en) * | 2016-11-10 | 2019-07-23 | 莱卡地球系统公开股份有限公司 | Laser scanner |
| CN108344379A (en) * | 2018-01-23 | 2018-07-31 | 上海大学 | A kind of system and method measuring insulator cross-section profile shape and creepage distance |
| CN109238162A (en) * | 2018-09-25 | 2019-01-18 | 浙江科技学院 | A kind of tunnel 3 d deformation monitoring and method for early warning |
| CN211043671U (en) * | 2019-09-25 | 2020-07-17 | 武汉海云空间信息技术有限公司 | Synchronous controller module for laser radar and laser radar |
| CN113847898A (en) * | 2021-09-24 | 2021-12-28 | 云南农业大学 | Multipoint distributed rail profile on-line detection device |
| CN114166147A (en) * | 2021-12-16 | 2022-03-11 | 上海应用技术大学 | Portable detector and method for steel rail profile based on three-dimensional laser scanning technology |
Also Published As
| Publication number | Publication date |
|---|---|
| CN116592791A (en) | 2023-08-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107340522B (en) | Laser radar positioning method, device and system | |
| Mills et al. | Geomatics techniques for structural surveying | |
| CN112907727B (en) | Calibration method, device and system of relative transformation matrix | |
| US20020162886A1 (en) | Portable apparatus for 3-dimensional scanning | |
| CN105486235A (en) | A target measuring method in ball machine video images | |
| CN111780716A (en) | Monocular real-time distance measurement method based on target pixel area and aspect ratio | |
| CN111402411A (en) | Scattered object identification and grabbing method based on line structured light | |
| US20190080471A1 (en) | Distance measurement system and distance measurement method | |
| US11692812B2 (en) | System and method for measuring three-dimensional coordinates | |
| JP2017524122A (en) | Method and apparatus for measuring displacement of mobile platform | |
| JP2017096813A (en) | Calibration device, calibration method, and calibration program | |
| JP2017004228A (en) | Method, device, and program for trajectory estimation | |
| Harchowdhury et al. | Coordinated nodding of a two-dimensional lidar for dense three-dimensional range measurements | |
| CN112684797B (en) | Obstacle map construction method | |
| CN111385558B (en) | TOF camera module precision measurement method and system thereof | |
| CN116592791B (en) | Shape measurement method, device, apparatus and storage medium | |
| CN108776338A (en) | Signal source space method for sensing, device and active sensor-based system | |
| CN109765567B (en) | Two-dimensional laser range finder positioning method based on cuboid calibration object | |
| CN116592766A (en) | Precise three-dimensional measurement method and device based on fusion of laser and monocular vision | |
| CN116755104A (en) | Method and equipment for positioning object based on three points and two lines | |
| CN112556596B (en) | Three-dimensional deformation measurement system, method, device and storage medium | |
| CN111504269B (en) | Underwater scale measurement method and device thereof | |
| CN112229478A (en) | Method and system for monitoring height change in process of material pile operation | |
| CN114492070A (en) | High-precision mapping geographic information virtual simulation technology and device | |
| CN113487685A (en) | Calibration method, device and equipment of line laser scanning camera and storage medium |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address |
Address after: Room 572, 18th Floor, Building B4, Phase I, Longshan Innovation Park, Wuhan Future Science and Technology City, No. 999 Gaoxin Avenue, Donghu New Technology Development Zone, Wuhan City, Hubei Province, 430000 Patentee after: Wuhan Haiwei Technology Co.,Ltd. Country or region after: China Address before: 430000 room 1588-2, 15 / F, B3 building, zone II, National Geospatial Information Industry base, No. 3, wudayuan 4th Road, East Lake New Technology Development Zone, Wuhan, Hubei Patentee before: WUHAN HAIWEI TECHNOLOGY Co.,Ltd. Country or region before: China |
|
| CP03 | Change of name, title or address |