Device for indoor calibration in cooperation with binocular camera

Abstract

The invention discloses a device for indoor calibration by matching with a binocular camera, which mainly comprises a camera guide rail, a support, an adjusting turntable and a mounting turntable, and can be used for indoor calibration of the binocular camera by matching with the binocular camera, a collimator, an electronic theodolite and a computer. According to the invention, translation of the binocular camera on the camera guide rail along the transverse axis direction can be realized, through the design of the support and the adjusting turntable, the mounting turntable carrying the collimator and the electronic theodolite is endowed with three rotational degrees of freedom, and meanwhile, through the design of the mounting turntable, the mounting heights of the collimator and the electronic theodolite can be adjusted. The device can assist in building a binocular vision system, can be compatible with binocular cameras or optical instruments of different specifications for indoor calibration within a certain distance, and has good universality.

Description

TECHNICAL FIELD

[0001] The application relates to a device for indoor calibration of a binocular camera, and belongs to the binocular calibration field. TECHNICAL BACKGROUND

[0002] A binocular vision system can measure three-dimensional space coordinates, has the characteristics of fast measurement and does not need to contact the measured object, and is used in many fields. The core of the construction of the binocular vision system is to calibrate the binocular camera used in the system, so as to obtain necessary system parameters. Existing calibration contents can be divided into indoor calibration, which aims to build a binocular camera, calibrate and obtain internal parameters of the system, and outdoor calibration, which aims to obtain unknown parameters in the transfer matrix.

[0003] The existing indoor calibration method of the binocular camera mainly relies on electronic theodolites and parallel light tubes and other optical instruments in the room, simulates an infinite target by using a scale plate, obtains and calculates internal and external parameters of the binocular camera, and calibrates the binocular camera (referring to Jiang Haijun. Camera calibration method under large field of view[D]. National University of Defense Technology, 2017.). The method mainly calibrates the internal and external parameters of the camera, needs to be carried out in indoor and outdoor environments respectively, and the parameters obtained by single indoor calibration are less, and outdoor calibration needs the assistance of a total station. In addition, the existing baseline distance measurement method relies on two electronic theodolites to measure a prefabricated calibration plate at the same time (referring to Li Qingan, Wang Xia, Sun Zhiyuan, Qiao Yanfeng and Zhu Wei. Calibration of binocular CCD measurement system based on electronic theodolite[J]. Journal of Instruments and meters, 2006(S1):188-190. DOI:10.19650 / j.cnki.cjsi.2006.s1.072.). The method needs to use two electronic theodolites and a prefabricated high flatness glass plate, has high requirements for equipment, has great limitations on the specifications of the calibrated binocular camera, and the baseline distance obtained by indirect measurement and calculation is not intuitive.

[0004] The existing method lacks a specific working device to assist in completing the indoor calibration of the binocular camera, needs precise movement of multiple target objects during calibration, is prone to cumulative error caused by multiple movements of optical instruments, has large calibration workload, and different binocular camera specifications also need corresponding calibration system construction, so there is a need for a device for reducing calibration movement error and assisting in indoor calibration of a binocular camera to solve the problems existing in the prior art. SUMMARY

[0005] The application aims to provide a device for indoor calibration of a binocular camera, solve the problems of large calibration workload of the binocular camera, easy accumulation of error, weak generalization of the camera specifications and the like in the prior art, and have reference significance for engineering practice.

[0006] To achieve the above object, the present application adopts the following scheme: The present application provides a device for indoor calibration of binocular camera, which comprises a camera guide rail, a support, an adjusting turntable, a mounting turntable, and can be used for indoor calibration of binocular camera in cooperation with binocular camera, collimator, electronic theodolite and computer, wherein: The binocular camera is mounted at both ends of the mounting crossbar, the mounting crossbar is mounted at the center of the sliding block, and the sliding block is placed on the guide rail and can slide along the guide rail. The camera guide rail is placed on the support. The adjusting turntable is mounted on the adjustable support. The mounting turntable is placed on the adjusting turntable. The collimator and the electronic theodolite are mounted on the adjustable support. The computer is connected to and controls the No. 1 camera and the No. 2 camera for obtaining imaging information of the two cameras.

[0007] Further, the central mounting crossbar of the camera guide rail is provided with a universal level bubble for controlling the relative levelness of the two cameras.

[0008] Further, the sliding block is connected with a vernier, and the guide rail is connected with a scale, the vernier and the scale cooperate with each other to measure the translation distance.

[0009] Further, the camera guide rail is placed on the four mounting columns in the support through the four adjusting studs at the bottom and the corresponding nuts.

[0010] Further, the adjustable support has two pairs of grooves which cooperate with the two pairs of ridges on the fixed support, and the fixed support has two locking screws for locking the adjustable support.

[0011] Further, the adjustable support has a ball head, the adjusting turntable has a ball joint and a locking screw at the bottom, and the ball head and the ball joint are assembled together and locked by the locking screw.

[0012] Further, the adjusting turntable has three positioning pins and one rotating shaft at the upper part, the axis of the rotating shaft coincides with the axis of the ball head in the vertical direction, the positioning pins are arranged at intervals of 90° with the rotating shaft as the center, and the distance from each positioning pin to the rotating shaft is equal.

[0013] Further, a rotating shaft hole is opened on the mounting turntable base plate of the mounting turntable, the position and hole diameter correspond to the rotating shaft, and two positioning holes are opened on the mounting turntable base plate, the position and hole diameter correspond to the two adjacent positioning pins.

[0014] Further, the two pairs of adjustable supports are fixed on the mounting turntable base, and the middle line between the two side supports of each pair of adjustable supports coincides with the line connecting the positioning hole below the middle line and the rotating shaft hole. A stepped long waist hole is formed on each side support, and a locking bolt is arranged on the stepped long waist hole, the locking bolt is used for connecting and fixing the base of the parallel light pipe and the electronic theodolite, and the height of the base on the adjustable support can be adjusted.

[0015] Compared with the prior art, the present application has the following beneficial effects: 1. The present application can quickly adjust the binocular camera to be in the same horizontal position by rotating the nut on the adjusting stud, cooperating with the installation crossbar and the universal level bubble, which is conducive to the construction of the binocular vision system.

[0016] 2. The present application can intuitively obtain the position degree of the sliding block before and after moving through the combination of the vernier and the scale, and then quickly obtain the baseline distance of the binocular camera, which is intuitive and simple to operate.

[0017] 3. The present application gives the mounting turntable three degrees of rotational freedom by cooperating the ball head with the ball joint; and gives the parallel light pipe and the electronic theodolite the freedom of translation along the horizontal axis and the vertical axis by cooperating the fixed support with the adjustable support and designing the adjustable support. The present application can be compatible with different specifications of binocular cameras or optical instruments, and can realize indoor calibration within a certain distance, which has strong universality.

[0018] 4. The present application can rotate the mounting turntable to turn the electronic theodolite to the other side when using the parallel light pipe, and then turn back to the original position when using the electronic theodolite by cooperating the positioning pin with the positioning hole, which reduces the number of debugging and calibrating the optical instrument, improves the error caused by frequent moving and recalibrating the optical instrument, and greatly reduces the related workload. DETAILED DESCRIPTION

[0019] Figure 1 is a device schematic diagram of the present application.

[0020] Figure 2 is a camera guide rail schematic diagram.

[0021] Figure 3 is a support schematic diagram.

[0022] Figure 4 is an adjusting turntable schematic diagram.

[0023] Figure 5 is a mounting turntable schematic diagram.

[0024] In the diagram: binocular camera (1), camera 1 (11), camera 2 (12), camera guide rail (2), slider (21), guide rail (22), vernier (23), scale (24), adjusting stud (25), mounting crossbar (26), universal level (27), support (3), fixed support (31), adjustable support (32), ball head (33), locking screw (34), mounting column (35), adjusting turntable (4), positioning pin (41), rotating shaft (42), ball joint (43), locking screw (44), adjusting turntable base plate (45), mounting turntable (5), mounting turntable base plate (51), adjustable bracket (52), locking bolt (53), rotating shaft hole (54), positioning hole (55), collimator (6), electronic theodolite (7), computer (8). Detailed Implementation

[0025] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments: like Figure 1 As shown, this invention provides a device for indoor calibration of a binocular camera. The device includes a camera guide rail (2), a support (3), an adjustment turntable (4), and a mounting turntable (5). It can be used with a binocular camera (1), a collimator (6), an electronic theodolite (7), and a computer (8) for indoor calibration of the binocular camera. Specifically: the binocular camera (1) is the object to be set up and calibrated; the camera guide rail (2) supports the binocular camera (1), allowing it to move along the guide rail, and can also assist in measuring the baseline distance, and adjust the binocular camera (1) to a horizontal state using a gimbal level (27); the support (3) connects all parts of the device, providing support, and can also... The adjustment turntable (4) provides the conditions for longitudinal movement; the adjustment turntable (4) is responsible for supporting the installation turntable (5) and connecting itself to the support (3), while providing three rotational degrees of freedom for the installation turntable (5); the installation turntable (5) is responsible for installing optical instruments and providing them with the conditions for movement along the vertical axis, while the installation turntable (5) can rotate around the rotation axis (42); the collimator (6) is responsible for providing a parallel light source to assist in the construction of the binocular vision system; the electronic theodolite (7) is responsible for leveling the camera and assisting in the calibration of the binocular camera; the computer (8) connects to and controls camera 1 (11) and camera 2 (12) to obtain the imaging information of the above two cameras and assist in the calibration of the binocular camera.

[0026] like Figure 2 As shown, a gimbal level (27) is installed in the center of the mounting bar (26) to ensure that the binocular camera (1) is in a horizontal position. Camera 1 (11) and camera 2 (12) are installed at both ends of the mounting bar (26). The upper and lower end faces of the cameras, the upper end face of the mounting bar (26), and the bottom face of the gimbal level (27) are parallel to each other.

[0027] The binocular camera (1) is fixed in the center of the slider (21) by means of a mounting bar (26).

[0028] like Figure 3 As shown, a vernier (23) is connected to the slider (21), and a ruler (24) is connected to the guide rail (22). The zero mark of the vernier (23) and the center line of the binocular camera (1) are in the same vertical plane. The vernier (23) and the ruler (24) work together to measure distance with an accuracy of 0.02 mm.

[0029] The camera rail (2) is placed on the four mounting posts (35) in the support (3) by four adjusting studs (25) at the bottom and corresponding nuts. The height of the camera rail can be adjusted or it can be adjusted to a horizontal position by rotating the nuts.

[0030] like Figure 4 As shown, the adjustable support (32) has two pairs of grooves that engage with the two pairs of ridges on the fixed support (31). The fixed support (31) has two locking screws (34) for locking the adjustable support (32). When it is necessary to change the extension length of the adjustable support (32), first loosen the locking screws (34), then pull out or retract the adjustable support (32), and finally tighten the locking screws (34) to fix it.

[0031] The adjustable support (32) has a ball head (33) at its end, which is engaged with the ball joint (43) at the bottom of the adjustable turntable (4) and fixed by a locking screw (44); this method gives the adjustable turntable (4) and the mounting turntable (5) on which the optical instrument is mounted three degrees of rotational freedom while connecting the adjustable turntable (4) to the adjustable support (32).

[0032] like Figure 5 As shown, the upper part of the adjustment turntable (4) has 3 positioning pins (41) and 1 rotating shaft (42). The axis of the rotating shaft (42) coincides with the vertical axis of the ball head (33). The positioning pins (41) are arranged at 90° intervals with the rotating shaft (42) as the center, and the distance from each positioning pin (41) to the rotating shaft (42) is equal. The mounting turntable base plate (51) of the mounting turntable (5) has 1 rotating shaft hole (54) with the position and diameter corresponding to the rotating shaft (42). The mounting turntable base plate (51) has 2 positioning holes (55) with the position and diameter corresponding to the 2 adjacent positioning pins (41).

[0033] In actual use, the pivot hole (54) coincides with the pivot (42), and the two positioning holes (55) coincide with the two adjacent positioning pins (41) (e.g. Figure 5, the right side and the middle positioning pin first coincides with the positioning hole), so that the installation turntable (5) is fixed on the adjusting turntable (4); when conversion is needed, the installation turntable (5) is lifted and rotated by 90°, so that the positioning hole coincides with another positioning pin (for example Figure 5 , at this time the left side and the middle positioning pin coincides with the positioning hole again), so as to complete the conversion of the optical instrument.

[0034] As shown in Figure 5 , the adjustable supports (52) are two pairs in total and are fixed on the installation turntable base plate (51), and the middle line between the two supports of each pair of adjustable supports (52) coincides with the line connecting the positioning hole (55) below and the rotating shaft hole (54). This design can ensure that even if the installation turntable (5) is rotated, the axis of the optical instrument installed on the adjustable support (52) can still point to the binocular camera (1) along the longitudinal axis direction.

[0035] Each side support has a stepped long waist hole and is provided with a locking bolt (53) for connecting and fixing the base of the collimator (6) or the electronic theodolite (7) and adjusting the height of the base on the adjustable support (52). When the locking bolt (53) is tightened, the base of the collimator or the electronic theodolite can be locked at any position within the length limit of the long waist hole, and when the locking bolt (53) is loosened, the base can move within the length limit of the long waist hole, so as to adjust the height of the base on the adjustable support (52).

[0036] The general steps of using the device to build and calibrate the binocular vision system are as follows: S1) The device is arranged in the room, and the installation cross rod (26), the camera guide rail (2), the support (3), the adjusting turntable (4), and the installation turntable (5) are installed according to the schematic diagram Figure 1 , the bubble of the universal level bubble (27) is located at the center by rotating the corresponding nut on the adjusting stud (25), and the installation cross rod (26) is in a horizontal state; S2) No. 1 camera (11) is installed on the installation cross rod (26), the slide block (21) is moved, and the camera is roughly moved to the center of the camera guide rail (2). The electronic theodolite (7) is installed on the adjustable support (52) opposite the camera guide rail (2), and the height of the base is adjusted so that the lens of No. 1 camera (11) is at the same height as the lens of the electronic theodolite (7); S3) The position of No. 1 camera (11) is adjusted by the electronic theodolite based on the outer end face of the installation cross rod (26), so as to ensure that the lens mounting end face of No. 1 camera (11) is parallel to the outer end face of the installation cross rod (26), and the installation position of No. 1 camera (11) relative to the installation cross rod (26) is fixed; S4) Rotate the mounting turntable (5) by 90°, so that the other pair of adjustable supports (52) is opposite the camera guide rail (2), and install the collimator (6) on the adjustable support (52), so that the lens of the collimator (6) is at about the same height as the lens of the No. 1 camera (11); S5) Connect the No. 1 camera (11) with the computer (8), and the computer generates a bright spot at the center of the displayed field of view of the No. 1 camera (11). Turn on the collimator (6), and by adjusting the height of the base of the collimator (6) on the adjustable support (52) and adjusting the rotation of the turntable (4) around the ball head (33), make the star point image of the collimator (6) be imaged at the center of the field of view of the No. 1 camera (11). That is, make the bright spot coincide with the star point image in the image displayed by the computer; S6) Keep the position and posture of the collimator (6) determined in S5) unchanged, install the No. 2 camera (12) on the mounting crossbar (26) and connect it with the computer (8). Move the slide block (21) to make the star point image of the collimator (6) enter the field of view of the No. 2 camera (12), and adjust the mounting posture of the No. 2 camera (12) to make the star point image of the collimator (6) coincide with the bright spot at the center of the field of view of the No. 2 camera (12); S7) Rotate the mounting turntable (5) back by 90°, and move the slide block (21) to make the electronic theodolite (7) re-opposite the No. 1 camera (11). Remove the lenses of the two cameras, adjust the electronic theodolite (7) to make the cross image emitted thereby be at the center of the field of view of the No. 1 camera (11), and record the degree of the vernier (23) on the scale (24) at this time Move the slide block (21) to make the cross image be at the center of the field of view of the No. 2 camera (12), and record the degree of the vernier (23) on the scale (24) at this time ; The calibrated baseline distance of the binocular camera is represented as: ; From the above, the application can assist in the construction of a binocular vision system and indoor calibration of a binocular camera, and can provide a certain reference for engineering practice.

[0037] The above is only a specific implementation in the application, but the protection scope of the application is not limited thereto, and any changes or modifications made by those skilled in the art within the spirit and principles of the application shall be covered within the patent scope of the application.

Claims

1. A device for indoor calibration in conjunction with a binocular camera, characterized in that, The device includes a camera guide rail (2), a support (3), an adjustment turntable (4), and a mounting turntable (5), and can be used with a binocular camera (1), a collimator (6), an electronic theodolite (7), and a computer (8) for indoor binocular aiming, wherein: The binocular camera (1) includes camera 1 (11) and camera 2 (12). The camera guide rail (2) includes a slider (21), a guide rail (22), a vernier (23), a scale (24), an adjusting stud (25), a mounting crossbar (26), and a universal level (27). The support (3) includes a fixed support (31), an adjustable support (32), a ball joint (33), a locking screw (34), and a mounting post (35). The adjusting turntable (4) includes a positioning pin (41), a rotating shaft (42), a ball joint (43), a locking screw (44), and an adjusting turntable base plate (45). The mounting turntable (5) includes a mounting turntable base plate (51), an adjustable bracket (52), a locking bolt (53), a rotating shaft hole (54), and a positioning hole (55). The binocular camera (1) is installed at both ends of the mounting crossbar (26), the mounting crossbar (26) is installed in the center of the slider (21), and the slider (21) is placed on the guide rail (22) and can slide along the guide rail (22); The camera guide rail (2) is placed on the support (3); The adjustable turntable (4) is mounted on the adjustable support (32); The mounting turntable (5) is placed on the adjusting turntable (4); The collimator (6) and the electronic theodolite (7) are mounted on an adjustable bracket (52); The computer (8) connects to and controls camera 1 (11) and camera 2 (12) to acquire their imaging information.

2. The device for indoor calibration in conjunction with a binocular camera according to claim 1, characterized in that, The camera guide rail (2) has a universal level bubble (27) in the center of the mounting crossbar (26).

3. The device for indoor calibration in conjunction with a binocular camera according to claim 1, characterized in that, A vernier (23) is connected to the slider (21); a ruler (24) is connected to the guide rail (22); the vernier (23) and the ruler (24) cooperate to measure the translation distance.

4. The device for indoor calibration in conjunction with a binocular camera according to claim 1, characterized in that, The camera guide rail (2) is mounted on the four mounting posts (35) in the support (3) by four adjusting studs (25) at the bottom and corresponding nuts.

5. The apparatus for indoor calibration in conjunction with a binocular camera according to claim 1, characterized in that, The adjustable support (32) has two pairs of grooves that engage with the two pairs of ridges on the fixed support (31); the fixed support (31) has two locking screws (34) for locking the adjustable support (32).

6. The apparatus for indoor calibration in conjunction with a binocular camera according to claim 1, characterized in that, The adjustable support (32) has a ball head (33); the bottom of the adjustable turntable (4) has a ball joint (43) and a locking screw (44). The ball head (33) is assembled with the ball joint (43) and locked by the locking screw (44).

7. The apparatus for indoor calibration in conjunction with a binocular camera according to claim 1, characterized in that, The upper part of the adjustment turntable (4) has 3 positioning pins (41) and 1 rotating shaft (42). The axis of the rotating shaft (42) coincides with the axis of the ball head (33) in the vertical direction. The positioning pins (41) are arranged at 90° intervals with the rotating shaft (42) as the center, and the distance from each positioning pin (41) to the rotating shaft (42) is equal.

8. The apparatus for indoor calibration in conjunction with a binocular camera according to claim 1, characterized in that, The mounting turntable (5) has a rotating shaft hole (54) on its mounting turntable base plate (51), the position and diameter of which correspond to the rotating shaft (42); the mounting turntable base plate (51) has two positioning holes (55), the position and diameter of which correspond to the two adjacent positioning pins (41).

9. The apparatus for indoor calibration in conjunction with a binocular camera according to claim 1, characterized in that, There are two pairs of adjustable brackets (52), which are fixed on the mounting turntable base plate (51). The center line between the two brackets of each pair of adjustable brackets (52) coincides with the line connecting the positioning hole (55) below it to the rotating shaft hole (54). Each side of the bracket has a stepped elongated hole and a locking bolt (53); the locking bolt (53) is used to connect and fix the base of the parallel light tube (6) and the electronic theodolite (7), and can adjust the height of the base on the adjustable bracket (52). Claim 1.

Images