CN105635516A - Desktop type 3D scanner - Google Patents

Abstract

The invention discloses a desktop type 3D scanner. The desktop type 3D scanner comprises an information acquisition part and an information processing part, wherein the information acquisition part is concise in structure, easy to manufacture, relatively low in cost and easy to popularize and has good application prospect; the information processing part is used for combining the traditional triangular ranging method with the modern common CMOS; by means of matching of a linear laser and an electric turntable, close-distance and high-precision laser ranging of a measurement object can be realized within a short time through later precise data processing; compared with the field-depth camera type scanner, the desktop type 3D scanner has relatively high scanning precision; and a good 3D scanning experience is provided for users.

Description

Table top type 3D scanner

Technical field

The present invention relates to a kind of 3D scanner, be specifically related to a kind of Table top type 3D scanner, for the measurement of the structure of 3D model of certain size article and relevant parameter, belong to reverse-engineering field.

Background technology

3D scanning technique is to be obtained a kind of new technique of a 3D model in kind by related scans equipment. Along with the progress of technology, the 3D technology printing to representative with 3D is vigorously developed, and progressively comes into our life. 3D scans as associated and provided basis to a certain extent a kind of technology, will have wide prospect in future.

The 3D existed on the market at present scan equipment towards client be usually enterprise or school, although precision is high, but cost and cost are also very high, and this will necessarily affect 3D and scan the popularization of this technology that should bring benefit to the mankind.

Along with the appearance of domestic level 3D printer, corresponding domestic level 3D scanner will be had strong demand by society.

Utilize depth of field camera to realize the equipment of 3D scanning despite some applicable domestic in the market, for instance the 3D based on Microsoft Kinect scans equipment, but this kind of 3D scans equipment and there is the problem that scanning accuracy is relatively low.

Summary of the invention

For solving the deficiencies in the prior art, it is an object of the invention to provide a kind of Table top type 3D scanner, not only scanning accuracy is high for it, and cost is low.

In order to realize above-mentioned target, the present invention adopts the following technical scheme that:

A kind of Table top type 3D scanner, including: information gathering portion and information treatment part, it is characterised in that

Aforementioned information collection portion includes: base (11), cmos image harvester (14), electrical turntable (15) and two linear laser (12, 13), aforementioned cmos image harvester (14) is arranged on base (11) by vertical support (16), aforementioned electrical turntable (15) is positioned at the dead ahead of cmos image harvester (14), it is arranged on base (11) by turret supports (17), and rotated in the horizontal plane by motor (18) driving, aforementioned linear laser instrument (12, 13) it is positioned in same level with cmos image harvester (14), and it is symmetrically distributed in the both sides of the axis of cmos image harvester (14), two linear laser (12, 13) the infrared wordline got intersects, the dead in line of reticule and electrical turntable (15),

The infrared wordline that linear laser (12,13) is got demarcates the point on object to be scanned, signal is carried out information gathering through 850nm narrow band pass filter by cmos image harvester (14), in the process that electrical turntable (15) rotates a circle, cmos image harvester (14) just can complete body surface information gathering work a little, all images signal collected is transferred to information treatment part by USB interface, and to carry out storage etc. pending.

Aforesaid Table top type 3D scanner, it is characterised in that aforementioned information process portion utilizes virtual coordinates that the picture signal collected is converted to 3D model, and concrete transformation process is:

One, right angled triangle ABC is built:

(1) optical center of cmos image harvester (14) is designated as a C;

(2) on the axis of electrical turntable (15), take one point union be designated as an A, put A contour with some C, light vertical incidence cmos image harvester (14) in straight line AC direction;

(3) cross some C in the horizontal plane to make the reverse extending line of an infrared wordline that the vertical line BC, vertical line BC of straight line AC and linear laser (12) get or an infrared wordline and intersect at a B;

(4) A, some B, some C form right angle triangle ABC are put;

Two, the plane of reference is built:

(1) it is in the part in cmos image harvester (14) visual field removes any one point union outside an A at line segment AB is designated as an E, be the vertical line EF of straight line AC, vertical line EF and straight line AC through an E and intersect at a F;

(2) plane being perpendicular to plane ABC is taken as the plane of reference through line segment EF;

Three, relevant parameter is determined:

(1) EF distance, BE distance, BC distance, AB distance are measured;

(2) calculate amplification n, aforementioned amplification n and refer to the pixel number purpose ratio of the actual physics length on the plane of reference in kind and imaging;

Four, the relative altitude h of object point, relative level distance l are calculated_bo:

(1) picture point corresponding to labelling point E is a some E ', and the picture point corresponding to object point point O ' on surface in kind is a some O ", put O " relative coordinate of corresponding point E ' be (x, y);

(2) order point O ' is projected as an O on plane ABC, similar to triangle OBC according to triangle OED, calculating OB distance l_bo:

$l_{bo}=\frac{l_{be}}{1-\frac{xn}{l_{bc}}}$

(3) junction point O ' and some C, line segment O ' C hand over the plane of reference in a D, junction point D ' and to put D at the projection intersection section EF of horizontal plane A BC in a D ', line segment O ' C, similar to triangle O ' OC according to triangle D ' DC, seek the length h of line segment O ' O:

$h=\frac{yn}{1-\frac{xn}{l_{bc}}}$

Five, set up cylindrical coordinate and determine cylindrical coordinates parameter:

(1) with an A for initial point, cross some A and be perpendicular to the straight line of plane ABC, remember that this straight line is z-axis, set up cylindrical coordinate with straight line AC for x-axis;

(2) cylindrical coordinates parameter r, ��, z are respectively as follows:

R=l_ab-l_bo

��=�� t

Z=h

In formula, �� is the rotational angular velocity of electrical turntable (15), and t is the rotation time of electrical turntable (15);

(3) so far, the picture signal collected has been completely converted into 3D model by information treatment part.

Aforesaid Table top type 3D scanner, it is characterised in that the live width of the laser rays of linear laser (12,13) is taken as a pixel wide.

Aforesaid Table top type 3D scanner, it is characterised in that before the picture signal collected is converted to 3D model by aforementioned information process portion, first carries out binary conversion treatment by the picture signal collected, and is purified by filter algorithm of making an uproar.

The invention have benefit that:

(1) CMOS common traditional triangle telemetry and modern times is combined, utilize the collocation of linear laser and electrical turntable, the data accurate by the later stage process, achieve at short notice to measure object closely, high-precision laser ranging, there is higher scanning accuracy compared to the scanner of depth of field camera-type, provided the user good 3D scanning and experienced;

(2) simple for structure, it is easy to manufacture, less costly, it is easy to universal, have a good application prospect.

Accompanying drawing explanation

Fig. 1 is the structural representation in the information gathering portion of the Table top type 3D scanner of the present invention;

Fig. 2 is the top view in the information gathering portion in Fig. 1;

Fig. 3 is the schematic diagram of traditional trigonometry laser ranging;

Fig. 4 is the schematic diagram of the trigonometry laser ranging of the present invention.

The implication of accompanying drawing labelling in figure: 11-base, 12-linear laser, 13-linear laser, 14-CMOS image acquisition device, 15-electrical turntable, 16-found support, 17-turret supports, 18-motor, 19-object.

Detailed description of the invention

Below in conjunction with the drawings and specific embodiments, the present invention done concrete introduction.

The Table top type 3D scanner of the present invention includes: information gathering portion and information treatment part.

One, information gathering portion

Seeing figures.1.and.2, information gathering portion includes: base 11, cmos image harvester 14, electrical turntable 15, linear laser 12 and linear laser 13.

Cmos image harvester 14 supports 16 installations on the pedestal 11 by vertical.

Electrical turntable 15 is positioned at the dead ahead of cmos image harvester 14, is installed on the pedestal 11 by turret supports 17, and is driven by motor 18 and rotate in the horizontal plane.

Linear laser 12 and linear laser 13 are positioned in same level with cmos image harvester 14, and it is symmetrically distributed in the both sides of the axis of cmos image harvester 14, the infrared wordline that linear laser 12 and linear laser 13 are got intersects, the dead in line of reticule and electrical turntable 15.

The infrared wordline that linear laser 12 and linear laser 13 are got demarcates the point on object 19 to be scanned, signal is carried out information gathering through 850nm narrow band pass filter by cmos image harvester 14, in the process that electrical turntable 15 rotates a circle, cmos image harvester 14 just can complete body surface a little information gathering work.

Two, information treatment part

The all images signal that cmos image harvester 14 collects is transferred to information treatment part by USB interface, information treatment part store, and then the picture signal collected is converted to 3D model.

Fig. 3 is the principle of traditional trigonometry laser ranging.

Principle according to laser triangulation range finding, on laser rays, each some position of imaging on cmos image harvester becomes a fixing functional relationship with the position of this some distance cmos image harvester.

In figure 3, S is the distance between laser instrument at grade and photographic head, �� is the angle between the plane that laser direction and laser instrument and the photographic head that laser instrument is launched forms, a virtual point can be calculated according to angle �� and photographic head focal distance f, the i.e. intersection point of dotted line and photographic head in figure, then can obtain Measuring Object relative laser device according to similar triangles relation and distance q between the plane that photographic head forms:

$\frac{f\cot \mathrm{\β}+x}{f}=\frac{s}{q}$

In formula, x represents the relative abscissa measuring the corresponding picture point of point relative to cmos image harvester central point.

Due to the low side concrete Parameter uncertainties of cmos image harvester, so traditional trigonometry laser ranging exists the deficiencies such as measurement result randomness is relatively big, certainty of measurement is not ideal enough.

In order to overcome above-mentioned deficiency, present invention employs a kind of new algorithm, this algorithm is by increasing a new plane of reference, and determine relevant parameter, can be implemented in the short time to measure object closely, high-precision laser ranging, higher scanning accuracy is had, it is possible to provide the user better 3D scanning and experience compared to the scanner of depth of field camera-type.

Electrical turntable 15 is to rotate continuously, the information that cmos image harvester 14 gathers is mainly a series of image, due to the impact by veiling glare, the picture signal collected first is carried out binary conversion treatment by information treatment part, and purified by filter algorithm of making an uproar, then again the picture signal after purifying is converted to 3D model.

With reference to Fig. 4, information treatment part utilizes the detailed process that the picture signal collected is converted to 3D model by virtual coordinates to be:

The first step: build right angled triangle ABC

1, the optical center of cmos image harvester 14 is designated as a C.

2, on the axis of electrical turntable 15, take one point union be designated as an A, put A contour with some C, the light vertical incidence cmos image harvester 14 in straight line AC direction.

Distance and the angle of visual field of cmos image harvester 14 between some A and some C are negative correlation.

3, cross some C in the horizontal plane to make the reverse extending line of an infrared wordline that the vertical line BC, vertical line BC of straight line AC and linear laser 12 get or an infrared wordline and intersect at a B.

4, A, some B, some C form right angle triangle ABC are put.

Second step: build the plane of reference

1, it is in the part in cmos image harvester 14 visual field removes any one point union outside an A at line segment AB is designated as an E, be the vertical line EF of straight line AC, vertical line EF and straight line AC through an E and intersect at a F.

2, the plane being perpendicular to plane ABC is taken as the plane of reference through line segment EF.

3rd step: determine relevant parameter

1, measure EF distance and (be designated as l_ef), BE distance (be designated as l_be), BC distance (be designated as l_bc), AB distance (be designated as l_ab)��

2, amplification n is calculated.

Amplification n refers to the pixel number purpose ratio of the actual physics length on the plane of reference in kind and imaging.

The image-forming principle of cmos image harvester is the imaging of pixel cell (i.e. pixel), and owing to we cannot calculate the actual size of picture, and the picture that can only obtain correspondence account for several pixel, so we refer to " amplification n " this concept.

4th step: calculate the relative altitude h of object point, relative level distance l_bo

1, the picture point corresponding to labelling point E is a some E ', and the picture point corresponding to object point point O ' on surface in kind is a some O ", put O " relative coordinate of corresponding point E ' be (x, y).

2, order point O ' is projected as an O on plane ABC, similar to triangle OBC according to triangle OED, calculating OB distance l_bo:

$l_{bo}=\frac{l_{be}}{1-\frac{xn}{l_{bc}}}.$

Calculate OB distance l_boDetailed process be:

By ED=x �� n, have according to similar triangle theory:

$\frac{ED}{BC}=\frac{OE}{OB}=\frac{OB-BE}{OB}$

That is:

$\frac{xn}{l_{bc}}=\frac{l_{bo}-l_{be}}{l_{bo}}$

Then have:

$l_{bo}=\frac{l_{be}}{1-\frac{xn}{l_{bc}}}.$

3, junction point O ' and some C, line segment O ' C hand over the plane of reference in a D, junction point D ' and to put D at the projection intersection section EF of horizontal plane A BC in a D ', line segment O ' C. Similar to triangle O ' OC according to triangle D ' DC, seek length (i.e. the relative altitude of object point and the horizontal plane) h of line segment O ' O:

$h=\frac{yn}{1-\frac{xn}{l_{bc}}}.$

The detailed process seeking the length h of line segment O ' O is:

By D'D=y �� n, have according to similar triangle theory:

$\frac{{\mathrm{DD}}^{\′}}{{\mathrm{OO}}^{\′}}=\frac{BE}{BO}=1-\frac{xn}{l_{bc}}$

Then have:

$h={\mathrm{OO}}^{\′}=\frac{yn}{1-\frac{xn}{l_{bc}}}.$

Note: all represent the length of subscript line segment in formula with lower target letter.

5th step: set up cylindrical coordinate

With an A for initial point, cross some A and be perpendicular to the straight line of plane ABC, remember that this straight line is z-axis, set up cylindrical coordinate with straight line AC for x-axis.

6th step: determine cylindrical coordinates parameter

By obtained as above to relative altitude h, the relative level distance l of object point (some O ')_bo, in conjunction with the uniform rotation angular velocity omega of electrical turntable 15, time t, the cylindrical coordinates of body surface each point can be obtained.

Cylindrical coordinates parameter r, ��, z are respectively as follows:

R=l_ab-l_bo

��=�� t

Z=h.

So far, the picture signal collected has been completely converted into 3D model by information treatment part.

In order to reduce amount of calculation, improving the computational accuracy of x and y, the live width of the laser rays of linear laser 12 and linear laser 13 is taken as a pixel wide simultaneously.

As can be seen here, the CMOS common traditional triangle telemetry and modern times is combined by the present invention, utilize the collocation of linear laser and electrical turntable, the data accurate by the later stage process, can scan at short notice and obtain the other threedimensional model of object submillimeter level, there is higher scanning accuracy compared to the scanner of depth of field camera-type, provided the user good 3D scanning and experienced.

Additionally, the overall cost of the scanner of the present invention is below 1000 yuan, the 3D scanner comparing same precision on the market greatly reduces cost, has a good application prospect.

Assuming that new reference plane adopt new algorithm, thus avoid the rigors to hardware parameter, so the present invention can effectively reduce the error of the range finding aspect caused due to the CMOS of low cost and the parameter error of relevant lens group, and more easily realize.

It should be noted that above-described embodiment does not limit the present invention in any form, all employings are equal to the technical scheme that the mode of replacement or equivalent transformation obtains, and all fall within protection scope of the present invention.

Claims (4)

1. a Table top type 3D scanner, including: information gathering portion and information treatment part, it is characterised in that

Described information gathering portion includes: base (11), cmos image harvester (14), electrical turntable (15) and two linear laser (12, 13), described cmos image harvester (14) is arranged on base (11) by vertical support (16), described electrical turntable (15) is positioned at the dead ahead of cmos image harvester (14), it is arranged on base (11) by turret supports (17), and rotated in the horizontal plane by motor (18) driving, described linear laser (12, 13) it is positioned in same level with cmos image harvester (14), and it is symmetrically distributed in the both sides of the axis of cmos image harvester (14), two linear laser (12, 13) the infrared wordline got intersects, the dead in line of reticule and electrical turntable (15),

The infrared wordline that linear laser (12,13) is got demarcates the point on object to be scanned, signal is carried out information gathering through 850nm narrow band pass filter by cmos image harvester (14), in the process that electrical turntable (15) rotates a circle, cmos image harvester (14) just can complete body surface information gathering work a little, all images signal collected is transferred to information treatment part by USB interface, and to carry out storage etc. pending.

2. Table top type 3D scanner according to claim 1, it is characterised in that described information treatment part utilizes virtual coordinates that the picture signal collected is converted to 3D model, and concrete transformation process is:

One, right angled triangle ABC is built:

(1) optical center of cmos image harvester (14) is designated as a C;

(2) on the axis of electrical turntable (15), take one point union be designated as an A, put A contour with some C, light vertical incidence cmos image harvester (14) in straight line AC direction;

(3) cross some C in the horizontal plane to make the reverse extending line of an infrared wordline that the vertical line BC, vertical line BC of straight line AC and linear laser (12) get or an infrared wordline and intersect at a B;

(4) A, some B, some C form right angle triangle ABC are put;

Two, the plane of reference is built:

(1) it is in the part in cmos image harvester (14) visual field removes any one point union outside an A at line segment AB is designated as an E, be the vertical line EF of straight line AC, vertical line EF and straight line AC through an E and intersect at a F;

(2) plane being perpendicular to plane ABC is taken as the plane of reference through line segment EF;

Three, relevant parameter is determined:

(1) EF distance, BE distance, BC distance, AB distance are measured;

(2) calculate amplification n, described amplification n and refer to the pixel number purpose ratio of the actual physics length on the plane of reference in kind and imaging;

Four, the relative altitude h of object point, relative level distance l are calculated_bo:

(1) picture point corresponding to labelling point E is a some E ', and the picture point corresponding to object point point O ' on surface in kind is a some O ", put O " relative coordinate of corresponding point E ' be (x, y);

(2) order point O ' is projected as an O on plane ABC, similar to triangle OBC according to triangle OED, calculating OB distance l_bo:

$l_{bo}=\frac{l_{be}}{1-\frac{xn}{l_{bc}}};$

(3) junction point O ' and some C, line segment O ' C hand over the plane of reference in a D, junction point D ' and to put D at the projection intersection section EF of horizontal plane A BC in a D ', line segment O ' C, similar to triangle O ' OC according to triangle D ' DC, seek the length h of line segment O ' O:

$h=\frac{yn}{1-\frac{xn}{l_{bc}}}$

Five, set up cylindrical coordinate and determine cylindrical coordinates parameter:

(1) with an A for initial point, cross some A and be perpendicular to the straight line of plane ABC, remember that this straight line is z-axis, set up cylindrical coordinate with straight line AC for x-axis;

(2) cylindrical coordinates parameter r, ��, z are respectively as follows:

R=l_ab-l_bo

��=�� t

Z=h

In formula, �� is the rotational angular velocity of electrical turntable (15), and t is the rotation time of electrical turntable (15);

(3) so far, the picture signal collected has been completely converted into 3D model by information treatment part.

3. Table top type 3D scanner according to claim 2, it is characterised in that the live width of the laser rays of linear laser (12,13) is taken as a pixel wide.

4. Table top type 3D scanner according to claim 2, it is characterised in that the picture signal collected is converted to before 3D model by described information treatment part, first carries out binary conversion treatment by the picture signal collected, and is purified by filter algorithm of making an uproar.