CN207963796U - Spatial digitizer in the caliberating device and mouth of spatial digitizer - Google Patents
Spatial digitizer in the caliberating device and mouth of spatial digitizer Download PDFInfo
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Abstract
The utility model provides spatial digitizer in a kind of caliberating device and mouth of spatial digitizer, wherein the caliberating device of spatial digitizer includes：The shaft of driving mechanism, driving mechanism is connect with calibration unit, for being driven to calibration unit, so that calibration unit motion；Control unit is connect with driving mechanism, for generating control instruction, wherein control instruction is used to control the opening and closing of driving mechanism.By technical solution provided by the utility model, it can solve the problem of that spatial digitizer calibration process is complicated in the prior art and operation error easily occur.
Description
Technical Field
The utility model relates to a three-dimensional scanner technical field particularly, relates to a calibration device and intraoral three-dimensional scanner of three-dimensional scanner.
Background
Three-dimensional scanners are used to detect and analyze the shape (geometry) and appearance data (color, surface albedo, etc.) of an object or environment in the real world, and the collected data is often used to perform three-dimensional reconstruction calculations to create a data model of the actual object in the virtual world. However, before scanning, the three-dimensional scanner needs to calibrate internal and external parameters of the camera, and needs to change the position and posture of the calibration plate for many times to acquire a required image, so as to calculate a required result.
Aiming at the problems that the three-dimensional scanner in the prior art is complex in calibration process and prone to misoperation, an effective solution is not provided at present.
SUMMERY OF THE UTILITY MODEL
The utility model provides a calibration device and intraoral three-dimensional scanner of three-dimensional scanner to three-dimensional scanner calibration process is complicated among the solution prior art, easy misoperation's problem appears.
In order to solve the above problem, according to the utility model discloses an aspect, the utility model provides a calibration device of three-dimensional scanner, include: the calibration unit is used for calibrating the camera; the rotating shaft of the driving mechanism is connected with the calibration unit and used for driving the calibration unit to enable the calibration unit to move; and the control unit is connected with the driving mechanism and used for generating a control command, wherein the control command is used for controlling the opening and closing of the driving mechanism.
Further, the calibration unit includes: the calibration seat is a circular table with an inclined angle on the front end surface and is connected with the driving mechanism; the calibration plate is arranged on the front end face of the calibration seat and used for calibrating the camera.
Further, the calibration apparatus of the three-dimensional scanner further includes: and the first end of the connecting unit is connected with the rotating shaft of the driving mechanism, and the second end of the connecting unit is connected with the calibration unit, so that the driving mechanism controls the calibration unit to move through the connecting unit.
Further, the connection unit includes: a coupling; the rotating screw is connected with the rotating shaft of the driving mechanism through the coupler; the rotating nut is sleeved on the periphery of the rotating screw in a matching manner and is connected with the calibration unit.
Further, the calibration apparatus of the three-dimensional scanner further includes: and the travel switch is connected with the driving mechanism and used for controlling the driving mechanism based on the moving position of the calibration unit.
Further, the calibration apparatus of the three-dimensional scanner further includes: and the slip ring unit is connected with the driving mechanism and used for conveying energy and communicating signals for the driving mechanism.
Further, the calibration apparatus of the three-dimensional scanner further includes: the calibration unit, the driving mechanism and the control unit are arranged in the shell, wherein an opening is formed in the first end, close to the calibration unit, of the shell, and the opening is used for installing a main body of the three-dimensional scanner.
Further, the housing is a cylindrical housing which can be split along the longitudinal direction, the opening is arranged corresponding to the calibration unit, and the calibration device of the three-dimensional scanner further comprises: the device ring is sleeved on the periphery of the first end of the shell and used for fastening the cylindrical shell which can be longitudinally disassembled.
Further, the calibration apparatus of the three-dimensional scanner further includes: the adapter, the adapter pad extremely the uncovered of shell is used for the switching calibration unit's optical display, just the adapter is connected with the three-dimensional scanner.
According to the utility model discloses a further aspect provides an intraoral three-dimensional scanner, including calibration equipment, calibration equipment is the calibration equipment of above-mentioned arbitrary three-dimensional scanner.
Use the technical scheme of the utility model, the order is markd the unit and is connected with actuating mechanism, drives the unit of maring through actuating mechanism, makes the unit motion of maring to change the position gesture of unit of maring, and then reach the technical purpose that three-dimensional scanner gathered, markd through the various position gestures to the unit of maring. In addition, the control unit is connected with the driving mechanism and controls the driving mechanism to be opened and closed based on the generated control instruction, so that the calibration unit is controlled to move, namely the calibration unit is controlled to change the position posture, the aim of directly and simply controlling the position posture of the calibration unit through the control unit is achieved, the calibration process of the three-dimensional scanner is simplified, and meanwhile the phenomenon of calibration misoperation is avoided.
Drawings
The accompanying drawings, which form a part of the specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without unduly limiting the scope of the invention. In the drawings:
fig. 1 shows an exploded view of a calibration apparatus of a three-dimensional scanner provided by the present invention;
fig. 2 shows an exploded view of a component of a calibration apparatus of a three-dimensional scanner provided by the present invention;
fig. 3 shows a functional explosion diagram of a calibration apparatus of a three-dimensional scanner provided by the present invention;
fig. 4 shows a schematic diagram of a calibration board pattern of a calibration apparatus of a three-dimensional scanner provided by the present invention.
Wherein the figures include the following reference numerals:
10. a calibration unit; 20. a drive mechanism; 30. a control unit; 40. a connection unit; 50. a travel switch; 60. a slip ring unit; 70. a housing; 80. a device ring; 90. an adapter; 11. a calibration seat; 12. calibrating the plate; 21. a rotating shaft; 41. a coupling; 42. rotating the screw; 43. rotating the nut; 44. a base.
Detailed Description
The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
As shown in fig. 1 to 3, an embodiment of the present invention provides a calibration apparatus for a three-dimensional scanner, the calibration apparatus for a three-dimensional scanner includes: a calibration unit 10 for performing camera calibration; the driving mechanism 20, a rotating shaft 21 of the driving mechanism 20 is connected with the calibration unit 10, and is used for driving the calibration unit 10 to make the calibration unit 10 move; and the control unit 30 is connected with the driving mechanism 20 and used for generating a control command, wherein the control command is used for controlling the opening and closing of the driving mechanism 20.
Use the technical scheme of the utility model, the order is markd unit 10 and is connected with actuating mechanism 20, drives demarcation unit 10 through actuating mechanism 20, makes demarcation unit 10 move to change the position gesture of demarcation unit 10, and then reach the technical purpose that three-dimensional scanner gathered, was markd through the various position gestures to demarcation unit 10. In addition, the control unit 30 is connected with the driving mechanism 20, and controls the driving mechanism 20 to open and close based on the generated control instruction, so as to control the calibration unit 10 to move, that is, control the calibration unit 10 to change the position and posture, thereby achieving the purpose of directly and simply controlling the position and posture of the calibration unit 10 through the control unit 30, so as to simplify the calibration process of the three-dimensional scanner, and simultaneously avoiding the occurrence of the calibration operation error.
Optionally, the Calibration unit 10 may be a Calibration board 12, which is called Calibration entirely in english, and is used for correcting lens distortion in machine vision, image measurement, photogrammetry, three-dimensional reconstruction, and other applications; determining a conversion relation between the physical size and the pixel; and determining the mutual relation between the three-dimensional geometric position of a certain point on the surface of the space object and the corresponding point in the image, shooting the array flat plate with the fixed spacing pattern by the camera, and calculating by a calibration algorithm to obtain a geometric model of the camera so as to obtain high-precision measurement and reconstruction results, wherein the array flat plate with the fixed spacing pattern is a calibration module.
Alternatively, as shown in fig. 4, the pattern on the calibration plate 12 is a dot matrix, and circles are disposed at the periphery of a plurality of dots, and the distance between the dots, the diameter of the circle, and the distance between the circles are all predetermined values. And then, acquiring a plurality of patterns on the calibration plate 12, acquiring two-dimensional coordinates of the patterns, calculating internal and external parameters of the camera, and completing a calibration algorithm.
Alternatively, the size of the calibration plate 12 may be 20 × 15mm2Wherein the area of the calibration plate 12 is 20 × 20mm2。
Alternatively, the driving mechanism 20 may be a micro motor, by which the calibration module is controlled to move.
Alternatively, the control unit 30 may be electrically connected to the driving mechanism 20 and the three-dimensional scanner, respectively, and the three-dimensional scanner and the driving mechanism 20 are controlled by one control unit 30, respectively.
Optionally, the utility model provides a calibration device of three-dimensional scanner can use in small-size three-dimensional scanner, realizes the automatic calibration to miniaturized three-dimensional scanner, and wherein, small-size three-dimensional scanner's size is 50 x 250mm, and three-dimensional scanner's axis direction's length is 250mm, and the cross sectional area on three-dimensional scanner's the axis vertical direction is 50 x 50mm2。
In this embodiment, the calibration unit 10 includes: the calibration base 11 is a circular table with a tilt angle on the front end surface, and the calibration base 11 is connected with the driving mechanism 20; calibration board 12, calibration board 12 set up in the preceding terminal surface of calibration seat 11, and calibration board 12 is used for carrying out the camera and marks. In order to obtain the postures of more calibration units 10, let the calibration unit 10 include: preceding terminal surface has the calibration seat 11 of inclination and is used for the calibration board 12 that the camera was markd, and then makes the calibration board 12 that sets up the terminal surface before the calibration seat 11 have certain inclination to calibration board 12 obtains the calibration board of multiple position gesture under the rotatory circumstances, has reached the variety that improves the calibration board 12 patterns of gathering, has increased the technological effect of the accuracy of demarcation.
Alternatively, the calibration plate 12 and the calibration base 11 may be provided in a single body, that is, the calibration plate 12 having a front end surface with an inclination angle.
Optionally, a plurality of calibration seats 11 with different inclination angles on the front end surface may be provided, and then under the condition of different requirements, the calibration seats 11 with different inclination angles are correspondingly used, that is, the calibration seats 11 are detachable and replaceable calibration seats 11.
In this embodiment, the calibration apparatus of the three-dimensional scanner further includes: and the first end of the connecting unit 40 is connected with the rotating shaft 21 of the driving mechanism 20, and the second end of the connecting unit 40 is connected with the calibration unit 10, so that the driving mechanism 20 controls the calibration unit 10 to move through the connecting unit 40. A more stable connection relationship between the driving mechanism 20 and the calibration unit 10 is achieved, and the possibility of occurrence of an accident is reduced.
Optionally, the connection unit 40 includes: a coupling 41; a rotating screw rod 42, wherein the rotating screw rod 42 is connected with the rotating shaft 21 of the driving mechanism 20 through a coupler 41; the rotating nut 43, the rotating nut 43 is fittingly sleeved on the periphery of the rotating screw rod 42, and the rotating nut 43 is connected with the calibration unit 10; the driving mechanism 20 controls the calibration unit 10 to rotate around the central axis of the connecting unit 40 by rotating the screw rod 42 and the rotating nut 43, and the calibration unit 10 moves along the central axis of the calibration unit 10. That is, the rotating screw 42 and the rotating shaft 21 of the driving mechanism 20 are connected by the coupling 41, when the driving mechanism 20 starts to operate, the rotating shaft 21 of the driving mechanism 20 starts to rotate, and further drives the rotating screw 42 connected by the coupling 41 to start to rotate, based on which, the rotating nut 43 sleeved on the periphery of the rotating screw 42 also starts to rotate, and the calibration unit 10 connected with the rotating nut 43 also starts to rotate.
Further, it should be noted that: based on the basic principle of the screw of the rotating shaft 21 and the rotating nut 43, when the driving mechanism 20 drives the rotating screw 42 and the rotating nut 43 to rotate, the rotating nut 43 can extend and retract within a certain range in the extending direction of the rotating screw 42 based on the rotation degree, so as to drive the calibration unit 10 to also extend and retract within a certain range, and further increase the change condition of the position and the posture of the calibration plate 12.
Alternatively, the coupling 41 is a device that connects the shaft and the rotating member, and rotates together during the process of transmitting motion and power, and is not disengaged under normal conditions.
Alternatively, the calibration plate 12 is connected to the driving mechanism 20 via a connection unit 40, and the plane of the calibration plate 12 is maintained at an angle, for example 30 °, to the optical axis of the camera by the calibration base 11.
It should be noted that: in the present embodiment, the coupling 41 is used to connect the turning screw 42 and the driving mechanism 20 in order to prevent the turning screw 42 from bearing an excessive load, and the coupling 41 also has the functions of compensating the offset between the two shafts due to inaccurate manufacturing and installation, deformation or thermal expansion during operation, and the like, and relieving and absorbing impact, i.e., the coupling 41 plays a certain role in protection.
In order to avoid the coupling 41, the turning screw 42 and the turning nut 43 from bearing excessive downward gravity (non-rotational force), the connection unit 40 further includes: and a base 44, wherein the base 44 is connected with the driving mechanism 20 and is used for placing the coupler 41.
In this embodiment, the calibration apparatus of the three-dimensional scanner further includes: a travel switch 50, the travel switch 50 being connected to the drive mechanism 20 for controlling the drive mechanism 20 based on the movement position of the calibration unit 10. Since the driving mechanism 20 and the calibration unit 10 are connected through the connection unit 40 including the rotating screw 42 and the rotating nut 43, based on the operation principle of the rotating screw 42 and the rotating nut 43, the calibration unit 10 connected to the rotating nut 43 will change its position based on the degree of rotation, that is, the calibration unit 10 will move a certain amount in the extending direction of the rotating screw 42, therefore, in the case that the driving mechanism 20 controls the calibration unit 10 to rotate, the calibration unit 10 will move a certain amount in the extending direction of the rotating screw 42, and the travel switch 50 includes a contact, when the calibration unit 10 touches its contact, the travel switch 50 immediately controls the driving mechanism 20 to stop operating, that is, the travel switch 50 immediately disconnects the circuit of the driving mechanism 20 to achieve the operating state of the driving mechanism 20, and avoids the calibration unit 10 from moving too far, causing damage to the components. Thereby, the calibration unit 10 can rotate within a certain range, and the connection unit 40 and the calibration unit 10 can be protected.
In addition, the travel switch 50 is mainly configured to turn on or off the control circuit by operating the contact thereof through collision of a mechanical moving member, that is, the travel switch 50 may further control the driving mechanism 20 according to a movement condition of a member that moves synchronously with the calibration unit 10, for example: the nut 43 is turned.
In addition, the drive mechanism 20 can be controlled by connecting and disconnecting the circuit of the drive mechanism 20 based on the travel switch 50, and therefore, different circuits of the drive mechanism 20 can be set so that the calibration unit 10 automatically stops moving, moves reversely, moves at a variable speed, and automatically moves back and forth at a certain moving position or moving travel.
In this embodiment, the calibration apparatus of the three-dimensional scanner further includes: and the slip ring unit 60 is connected with the driving mechanism 20, and is used for transmitting energy to the driving mechanism 20 and communicating signals. The drive mechanism 20 is based on its principle of operation and requires connection to a certain power supply line, for example, an electrical cord. And the driving mechanism 20 generates a control command based on the control unit 30 to perform an opening command or a closing command, it is necessary to connect a certain line for transmitting a signal, for example, an electric wire. In order to prevent the power transmission line and the signal transmission line from being subjected to a certain loss in the case where the driving mechanism 20 is continuously rotated by 360 °, the power transmission and signal transmission are performed by the slip ring unit 60, that is, the power transmission line and the signal transmission line are connected to the slip ring unit 60, and the slip ring unit 60 transmits power and a signal to the driving mechanism 20.
Optionally, the slip ring unit 60 comprises a conductive slip ring and a slip ring holder. The slip ring support is hollow cylinder, the conductive slip ring is cylinder matched with the hollow cylinder, and the periphery of the cylinder is provided with a thin-sheet circular ring.
In order to protect the calibration apparatus of the three-dimensional scanner, optionally, in this embodiment, the calibration apparatus of the three-dimensional scanner further includes: a housing 70, in which the calibration unit 10, the driving mechanism 20 and the control unit 30 are arranged, wherein a first end of the housing near the calibration unit 10 has an opening for mounting the main body of the three-dimensional scanner.
As an alternative example, the opening of the first end of the housing 70 is arranged in the direction of the central axis of the calibration unit 10.
Further, the housing 70 is provided with a communication hole at an end near the driving mechanism 20 so that a line for transmitting power and a line for transmitting a signal can be connected to the driving mechanism 20 inside the housing 70 through the communication hole.
In order to facilitate the mounting and dismounting of the housing, as an alternative example, the housing 70 is a column-shaped housing that is detachable in the longitudinal direction, and an opening is provided corresponding to the calibration unit 10.
Based on the column-shaped housing which can be split along the longitudinal direction, as an optional example, the calibration apparatus of the three-dimensional scanner further includes: the device ring 80 is sleeved on the periphery of the first end of the shell 70, and is used for fastening the cylindrical shell 70 which can be longitudinally disassembled.
In addition, the housing 70 may be fastened by other means, for example, by providing a plurality of snaps on the cylindrical housing 70 that is detachable in the longitudinal direction.
In this embodiment, in the calibration apparatus of the three-dimensional scanner, the calibration apparatus of the three-dimensional scanner further includes: the adapter 90 is plugged into an opening of the housing, and is used for switching the optical display of the calibration unit 10, and the adapter 90 is connected with the three-dimensional scanner. That is, the adapter 90 is disposed at the open position, so that the three-dimensional scanner can obtain the calibration patterns of the calibration unit 10 at various positions and postures, and further calculate the required calibration result to complete the calibration operation.
It should be noted that: as shown in fig. 1 and fig. 2, the device ring 80 is connected to the adapter 90 in a matching manner, the inner wall of the front end of the device ring 80 is connected to the adapter 90 in a clamping manner, and the inner wall of the rear end of the device ring 80 is connected to the periphery of the first end of the housing 70 in a clamping manner, so as to achieve the technical characteristic that the adapter 90 is plugged into the opening of the housing 70.
Another embodiment of the utility model provides an intraoral three-dimensional scanner, including calibration device, its calibration device is the calibration device of above-mentioned arbitrary three-dimensional scanner. Through using the technical scheme of the utility model, make calibration unit 10 be connected with actuating mechanism 20, drive calibration unit 10 through actuating mechanism 20, make calibration unit 10 move to change calibration unit 10's position gesture, and then reach the technical purpose that three-dimensional scanner gathered, markd through the various position gestures to calibration unit 10. In addition, the control unit 30 is connected with the driving mechanism 20, and controls the driving mechanism 20 to open and close based on the generated control instruction, so as to control the calibration unit 10 to move, that is, control the calibration unit 10 to change the position and posture, thereby achieving the purpose of directly and simply controlling the position and posture of the calibration unit 10 through the control unit 30, so as to simplify the calibration process of the three-dimensional scanner, and simultaneously avoiding the occurrence of the calibration operation error.
Optionally, six external parameters to be calibrated in the camera calibration work are provided, that is, the rotation angle around three coordinate axes in the rotation matrix and the displacement along three coordinate axes in the translation matrix; there are six internal parameters, namely Cx, Cy, Sx, Sy, f, and k, where Cx, Cy, Sy have been determined by pre-calibration. Therefore, only Sx, effective focal length f and radial distortion coefficient k in six external parameters need to be solved.
Optionally, the method adopts a camera model based on first-order radial distortion, utilizes a stepwise decomposition camera linear calibration method to decompose each parameter step by step, calculates a rotation matrix and a translation matrix by solving a linear equation system, and finally calculates the internal parameter focal length and the radial distortion coefficient. The specific derivation is as follows:
according to the projection and perspective transformation theory and the matrix transformation knowledge, the complete transformation from the three-dimensional world coordinate system to the computer image coordinate system can be divided into four steps:
(1) the transformation of the three-dimensional space coordinate system into the camera coordinate system, i.e. from (x, yw, zw) to (x, y, z).
Wherein,
wherein, R and T are respectively the rotation and translation transformation from the world coordinate system to the camera coordinate system, R is a 3 × 3 orthogonal matrix, T is a 3 × 1 translation vector, and the total number of independent variables is six. I.e. three corners reflecting a rotational transformation and three translational components reflecting a translational transformation.
Wherein,T＝[TxTyTz]。
(2) the ideal perspective projection transformation under the pinhole camera model, i.e. the transformation from (x, y, z) to (Xu, Yu).
Wherein,
(3) distortion model: the relationship between the actual image coordinates (Xd, Yd) and the ideal image coordinates (Xu, Yu) in the image coordinate system is described. Most experiments have shown that the distortion at the centre point of the image is small and the distortion at the edges of the image is large, so that kR is chosend 2As distortion factors, the following distortion model was established:
wherein, Xd＝(1+kRd 2)XuFormula (1.4);
Yd＝(1+kRd 2)Yuformula (1.5); rd 2＝Xd 2+Yd 2And Rd is the square of the radial radius and k is the radial distortion coefficient.
(4) The transformation of the actual image coordinates to computer image coordinates, i.e. from (Xd, Yd) to (Xf, Yf).
Wherein, Xf＝Cx+SxXdFormula (1.6); y isf＝Cy+SyYdThe expressions (1.7), (Cx, Cy) are coordinates of the center of the image stored in the computer frame, and Sx, Sy are the number of pixels (pixels/mm) per unit distance in the X and Y directions in the image plane, i.e., the scale factor.
if Sx/Sy is equal to β, Xd ═ Xf-Cx/Sy, and Xd ═ Xd'/β.
It can be seen that the parameters to be calibrated include:
external parameters: r and T share six independent variables;
the internal parameters are f is effective focal length, k is radial distortion coefficient, Sx and Sy are respectively proportional coefficient of X and Y directions, β is scale factor, and (Cx and Cy) are central coordinates of computer frame stored image.
Wherein Cx, Cy and Sy can be obtained by pre-calibration.
Setting a rotation matrixTranslation matrixThe Tx, Ty components of the rotation matrices R and T are calculated.
Obtained by the formula (1.1)From the formulae (1.2), (1.3), (1.4) and (1.5)Therefore, it is not only easy to useThe formula is subjected to line shifting and finishing to obtain:
optionally, for each index point, one of X 'may be listed when its three-dimensional coordinates and corresponding image coordinates are known'dThe equation of (c). In the above X'dIn the equation (2), seven elements of the column vector are unknowns, seven calibration points are taken, and the seven unknowns can be solved by solving a linear equation set. Considering that random errors exist in the values of three-dimensional coordinate points and image coordinates in the calibration process, some calibration points (A) and (B) should be additionally taken>7) And solving the optimal solution with the minimum total error of each calibration point according to the least square principle. Then, according to the orthogonal property of R of the rotation matrix, each element in the rotation matrix R and Tx and Ty can be further calculated.
Alternatively, solving the above overdetermined system of equations (N > ═ 7) using the least squares method may yield the following variables:
alternatively, β, Ty, Tx and R1, R2 can be calculated using the orthogonality of R (orthonormal matrix), as follows:
(1) calculate | Ty |, where | T |y|＝(α5 2+α6 2+α7 2)1/2。
(2) calculating β and Sx, wherein β ═ alpha1 2+α2 2+α3 2)1/2|Tyif yes, then Sx ═ β Sy.
(3) After obtaining | Ty |, there is still Ty symbol to be determined, and it is actually known from the imaging geometry that Xd and x have the same symbol, and Yd and y also have the same symbol, which can be used to determine Ty symbol. That is, after | Ty | is obtained, a feature point Pk (xk, yk, zk) is selected, Ty is assumed to be a positive sign, and r1 to r6 and Tx can be calculated using variables solved by the above-described overdetermined equation system (N > ═ 7).
Alternatively, x and y may be computed for the feature points. If x and Xd, y and Yd have the same sign at the moment, the Ty sign is positive, otherwise, the Ty sign is negative.
(4) knowing Ty and β, the above-described overdetermined system of equations (N) can be utilized>7) directly calculate r1-r6, Tx. By using the orthogonality of R and the right-hand system characteristic (corresponding to the world coordinate system as the right-hand system), it can be seen that R7-R9 is obtained by cross multiplication of the first two rows: r is7＝r2r6-r3r5；r8＝r3r4-r1r6；r9＝r1r5-r2r4。
through the above process, the Tx, Ty components and the image scale factor β in the entire rotation matrices R and T have been solved.
Alternatively, the Tz component of the effective focal length f, T and the lens distortion coefficient k are calculated to obtain:
suppose that: hx＝r1xw+r2yw+r3zw+Tx，Hy＝r4xw+r5yw+r6zw+Ty，W＝r7xw+r8yw+r9zw，fkH can be obtained as f.kx·f+Hxrd 2·fk-Xd·Tz＝Xd·W，Hy·f+Hxrd 2·fk-Yd·Tz＝Yd·W。
Optionally, for N feature points, performing joint optimal parameter estimation on the two equations by using a least square method to obtain f, fk, Tz, and further obtain f, k, Tz.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
Unless specifically stated otherwise, the relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.
In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the orientation words such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplification of description, and in the case of not making a contrary explanation, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be interpreted as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.
Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and if not stated otherwise, the terms have no special meaning, and therefore, the scope of the present invention should not be construed as being limited.
Claims (10)
1. A calibration device of a three-dimensional scanner is characterized by comprising:
a calibration unit (10) for performing camera calibration;
the rotating shaft (21) of the driving mechanism (20) is connected with the calibration unit (10) and used for driving the calibration unit (10) to enable the calibration unit (10) to move;
the control unit (30) is connected with the driving mechanism (20) and used for generating a control command, wherein the control command is used for controlling the opening and the closing of the driving mechanism (20).
2. Calibration arrangement of a three-dimensional scanner according to claim 1, wherein the calibration unit (10) comprises:
the calibration seat (11) is a circular table with an inclined angle on the front end surface, and the calibration seat (11) is connected with the driving mechanism (20);
the calibration plate (12), the calibration plate (12) set up in the preceding terminal surface of calibration seat (11), calibration plate (12) are used for carrying out camera calibration.
3. The calibration device of the three-dimensional scanner as claimed in claim 1, further comprising:
a connecting unit (40), wherein a first end of the connecting unit (40) is connected with the rotating shaft (21) of the driving mechanism (20), and a second end of the connecting unit (40) is connected with the calibration unit (10) for enabling the driving mechanism (20) to control the calibration unit (10) to rotate and/or move through the connecting unit (40).
4. Calibration arrangement of a three-dimensional scanner according to claim 3, wherein the connection unit (40) comprises:
a coupling (41);
the rotating screw (42), the rotating screw (42) is connected with the rotating shaft (21) of the driving mechanism (20) through the coupler (41);
the rotating nut (43), the rotating nut (43) is fittingly sleeved on the periphery of the rotating screw rod (42), and the rotating nut (43) is connected with the calibration unit (10).
5. The calibration device of the three-dimensional scanner as claimed in claim 3, further comprising:
a travel switch (50), the travel switch (50) being connected with the drive mechanism (20) for controlling the drive mechanism (20) based on the movement position of the calibration unit (10).
6. The calibration device of the three-dimensional scanner as claimed in claim 1, further comprising:
the slip ring unit (60) is connected with the driving mechanism (20) and used for transmitting energy to the driving mechanism (20) and communicating signals.
7. The calibration device of the three-dimensional scanner as claimed in claim 1, further comprising:
a housing (70), wherein the calibration unit (10), the driving mechanism (20) and the control unit (30) are arranged in the housing (70), and a first end of the housing close to the calibration unit (10) is provided with an opening for installing the main body of the three-dimensional scanner.
8. The calibration device of three-dimensional scanner according to claim 7, wherein the housing (70) is a column-shaped housing detachable along a longitudinal direction, the opening is disposed corresponding to the calibration unit (10), and the calibration device of three-dimensional scanner further comprises:
the device ring (80) is sleeved on the periphery of the first end of the shell (70) and used for fastening the cylindrical shell which can be disassembled along the longitudinal direction.
9. The calibration device of the three-dimensional scanner as claimed in claim 7, further comprising:
the adapter (90), adapter (90) fill to the uncovered of shell (70), be used for the switching the optical display of calibration unit (10), just adapter (90) are connected with the three-dimensional scanner.
10. An intraoral three-dimensional scanner comprising calibration means, characterized in that the calibration means are calibration means of the three-dimensional scanner according to any one of claims 1 to 9.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820389308.3U CN207963796U (en) | 2018-03-21 | 2018-03-21 | Spatial digitizer in the caliberating device and mouth of spatial digitizer |
| PCT/CN2018/085029 WO2019056755A1 (en) | 2017-09-19 | 2018-04-28 | Calibration apparatus, method and system for three-dimensional scanner, and intraoral three-dimensional scanner |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820389308.3U CN207963796U (en) | 2018-03-21 | 2018-03-21 | Spatial digitizer in the caliberating device and mouth of spatial digitizer |
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| CN207963796U true CN207963796U (en) | 2018-10-12 |
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| CN201820389308.3U Active CN207963796U (en) | 2017-09-19 | 2018-03-21 | Spatial digitizer in the caliberating device and mouth of spatial digitizer |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110132165A (en) * | 2019-04-23 | 2019-08-16 | 先临三维科技股份有限公司 | Calibration device for 3D scanner and intraoral 3D scanner |
| CN114205483A (en) * | 2022-02-17 | 2022-03-18 | 杭州思看科技有限公司 | Scanner precision calibration method and device and computer equipment |
| CN114652471A (en) * | 2021-04-22 | 2022-06-24 | 宁波频泰光电科技有限公司 | Calibrator for three-dimensional oral cavity scanner |
| CN115150517A (en) * | 2022-06-30 | 2022-10-04 | 先临三维科技股份有限公司 | Scanner base and scanner |
| CN118687473A (en) * | 2024-07-01 | 2024-09-24 | 滇西应用技术大学 | An automatic correction device for industrial three-dimensional scanner, use method and application |
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2018
- 2018-03-21 CN CN201820389308.3U patent/CN207963796U/en active Active
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110132165A (en) * | 2019-04-23 | 2019-08-16 | 先临三维科技股份有限公司 | Calibration device for 3D scanner and intraoral 3D scanner |
| CN114652471A (en) * | 2021-04-22 | 2022-06-24 | 宁波频泰光电科技有限公司 | Calibrator for three-dimensional oral cavity scanner |
| CN114652471B (en) * | 2021-04-22 | 2024-04-19 | 宁波频泰光电科技有限公司 | Calibrator for three-dimensional oral cavity scanner |
| CN114205483A (en) * | 2022-02-17 | 2022-03-18 | 杭州思看科技有限公司 | Scanner precision calibration method and device and computer equipment |
| CN114205483B (en) * | 2022-02-17 | 2022-07-29 | 杭州思看科技有限公司 | Scanner precision calibration method and device and computer equipment |
| CN115150517A (en) * | 2022-06-30 | 2022-10-04 | 先临三维科技股份有限公司 | Scanner base and scanner |
| CN118687473A (en) * | 2024-07-01 | 2024-09-24 | 滇西应用技术大学 | An automatic correction device for industrial three-dimensional scanner, use method and application |
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Address after: 311258 No. 1398, Wenbin Road, Wenyan street, Xiaoshan District, Hangzhou, Zhejiang. Patentee after: First facing the three dimensional Polytron Technologies Inc Address before: 311258 No. 1398, Wenbin Road, Wenyan street, Xiaoshan District, Hangzhou, Zhejiang. Patentee before: Hangzhou Shining 3D Technology Co., Ltd. |
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