CN103047944B - Three-dimensional object measuring method and device - Google Patents
Three-dimensional object measuring method and device Download PDFInfo
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- CN103047944B CN103047944B CN201310024956.0A CN201310024956A CN103047944B CN 103047944 B CN103047944 B CN 103047944B CN 201310024956 A CN201310024956 A CN 201310024956A CN 103047944 B CN103047944 B CN 103047944B
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Abstract
The invention discloses a three-dimensional object measuring method and device for solder paste printing and detecting. The three-dimensional object measuring method is characterized by comprising the following steps of: acquiring the height of an object by adopting an N-step phase shift method and a triangulation method, further acquiring three-dimensional data of the height, area, center, volume, shape and the like of a to-be-measured object, and judging whether a solder paste is qualified. The measuring device for implementing the method provided by the invention is simple in structure, is easy to operate, and is beneficial to the implementation of the N-step measuring method.
Description
Technical field
The present invention relates to three-dimensional body measuring technique, especially small items is measured, specifically tell about method and implement device thereof that three-dimensional body is measured, with obtain the area, center of this object, highly, the parameter such as shape, volume, the paste solder printing that can be applied in SMT (surface mounting technology) field detects.
Background technology
It has been a undisputable fact that paste solder printing flow process can produce a lot of defects, some reports even point out that this class defects count has accounted for 80% of overall defect quantity, and the well-known fact of another one is that tin cream amount is an important indicator of judgement quality of welding spot and reliability thereof.Adopting three-dimensional tin cream to detect (SPI) technology will contribute to reduce and in printing-flow, produce welding point defect, and can become the original loss that waste product brings that reduces by minimum doing over again (as cleaning circuit plate), another one benefit is that welding spot reliability will be guaranteed.
Result of calculation shows: the loss of paste solder printing defect is lost littlely 10 times than printing defects after Reflow Soldering before Reflow Soldering, loses littlely 70 times than on-line testing defect, loses little 700 times than planar disfigurement.As can be seen here, along with the appearance of tin cream detection technique, the flow process control that combines the front three-dimensional tin cream detection of paste solder printing and Reflow Soldering is just imperative, and in line, flow process is controlled has become chance of raising reliability and saving cost.
Common method for three-dimensional measurement, is mainly divided into contact and contactless two large classes at present.For contact type measurement, adopt the such equipment of similar three coordinate measuring machine, with probe contact measurement body surface, carry out body form measurement, the shortcoming of the method is apparent, and speed is slow, and invalid to the such flexible article of similar tin cream.And for non-contact measurement, because measuring speed is fast, and contact measurement object not, so there is clear superiority, at present mainly based on three major types technology: binocular vision, laser scanning and sine stripe projection.Wherein, binocular vision equipment cost is higher, and whole system structure is all very complicated with demarcation, so seldom adopt in industrial detection field.Laser scanning method, the measuring principle of employing is the same with sine stripe projection, and difference is, and the former adopts single laser to measure, and can only measure an object point on light at every turn, and overall rate will be slower than sine stripe projection.So industry projection algorithm that generally adopt or based on sine streak carries out three-dimensional body detection at present.But based on sine stripe projection algorithm, carry out three-dimensional body while detecting, easily occur that striped is piled up and the optical problem such as reflective, shade.
Summary of the invention
For this reason, especially for the paste solder printing accuracy of detection problem existing in SMT field, spy of the present invention provides a kind of three-dimensional body measuring method and measurement mechanism thereof, with obtain the area, center of tin cream, highly, the parameter such as shape, volume, thereby determine that whether paste solder printing qualified.
For achieving the above object, the present invention takes following technical scheme: a kind of three-dimensional body measuring method, it is characterized in that, and comprise the steps:
1) be provided with the measurement mechanism that comprises sample camera, light source and moving grating, the parameters of measurement mechanism is demarcated in advance, and the sampling camera ceramic motor used with moving grating is connected with computing machine;
2) measurement datum is placed on to device below, makes can obtain striped picture clearly on reference field;
3) open source of parallel light, controlling ceramic motor voltage is 0, makes grating move to origin position, and camera looks like to take pictures to the deforming stripe of origin position, is stored in computing machine;
4) control the n/N position that ceramic motor driving grating moves to fringe period successively, n=1... (N-1), once, camera all looks like to take pictures to deforming stripe and is stored in computing machine in every movement;
5) in each photos obtaining, computing machine extracts respectively the grey scale pixel value I of same pixel (x, y)
n(x, y), and utilize N step phase-shift method, try to achieve the initial bit phase φ of this pixel
0(x, y); The initial bit of other pixels is also tried to achieve with same method mutually;
6) determinand with certain altitude is placed on reference field, makes can obtain striped picture clearly on determinand;
7) equally according to above-mentioned 3)-6) operation of step, utilizes N step phase-shift method to try to achieve on determinand the deforming position phase φ producing with pixel corresponding on reference field after height change
h(x, y);
8) utilize formula AB=[φ
h(x, y)-φ
0(x, y)] * p/ (2 π), the plan range of trying to achieve this pixel changes, and wherein p is the fringe period that projection obtains, and is system constant;
9) according to triangulation formula: h=L*AB/ (AB+D), calculate the height h of this pixel, wherein L be camera photocentre to the vertical range of reference field, D is the horizontal range between camera and grating photocentre;
10) utilize 7)-9) computing method of step, try to achieve the height of other pixels of determinand, the altitude information of each pixel on comprehensive determinand, just can obtain the three-dimensional datas such as height, area, center, volume, shape of determinand;
11), according to three-dimensional datas such as the height of determinand, area, center, volume, shapes, judge that whether tin cream is qualified.
The height that the present invention is applicable to detect determinand is less than the object in grating deforming stripe cycle.
Described reference field is a plane.
Described moving grating can in conjunction with the measurement result of a plurality of gratings, be obtained weighted mean value according to weight for a plurality of, and actual measured results is multiplied by weighted mean value, obtains actual measurement height, can effectively avoid like this optical problem such as reflective, shade.
Described moving grating is sinusoidal grating or Ronchi grating.
Described N step phase-shift method, refers to: when optical grating mold plate is projected to three-dimensional diffuse reflection body surface, the deforming stripe picture of observing, is formulated as:
I(x，y)＝A(x，y)+B(x，y)*cos[φ(x，y)] (1)
(1), in formula, I (x, y) represents that planimetric coordinates is (x, the light intensity of object point y), A (x, y) is background intensity, B (x, y)/A (x, y) be fringe contrast, phase function φ (x, y) represents the striped distortion causing due to object surface shape, when grating is along often move to n/N step perpendicular to stripe direction, just produce a deforming stripe as I
n(x, y):
I
n(x，y)＝A
n(x，y)+B
n(x，y)*cos[φ
n(x，y)] (2)
Continuous moving and obtain K frame deforming stripe picture, thus can be in the hope of the position phase distribution phi (x, y) of this point:
φ(x，y)＝arctg{[∑I
n(x，y)*sin(2πn/N)]/[∑I
n(x，y)*cos(2πn/N)]} (3)
(2), in (3) formula, n=1 ... K, 3≤K≤N, A
n(x, y) is background intensity, B
n(x, y)/A
n(x, y) is fringe contrast, so from above formula, can be in the hope of φ (x, y).
In N step phase-shift method, the deforming position phase φ (x being calculated by formula (2), (3), y), must use unwrapping algorithm to recover original continuous distribution form, use φ (x, y) deduct the initial bit phase of this point, and require within the scope of arrive+π of must drop on-π of this phase differential, if discovery phase differential is super, go beyond the scope, just automatically by deforming position phase φ (x, y) add or deduct one-period π, until meet restriction.
A kind of device of realizing three-dimensional body measurement, it is characterized in that, comprise a worktable, on worktable, fix a column, on column, fix a camera and a grating erecting frame height variable, on described grating erecting frame, grating assembly is installed, described grating assembly comprises that one is slidably arranged in the lenticular lenses on grating erecting frame, with the source of parallel light that is positioned at lenticular lenses top, described lenticular lenses is driven by ceramic motor, and described camera and ceramic motor are by computer control.
Described camera and grating erecting frame are arranged on column by multidigit bolt hole, and the variation by position, hole changes its setting height(from bottom) on column.
On described grating erecting frame by a plurality of grating assemblies of a plurality of grating frame installations that branch out, described in each, on grating framework, be provided with slide rail, described lenticular lenses is slidably installed on described slide rail by grating installing plate, and described grating installing plate is driven and connected by described ceramic motor.
The present invention is owing to taking above technical scheme, it has the following advantages: the present invention adopts N step phase-shift measurement method, calculate the deforming position phase of object point to be measured, by the feature of deforming position phase, further try to achieve the in-plane displancement of object point, according to triangulation, try to achieve again the height of object point, and then try to achieve the parameters such as area, center, shape, volume, thereby determine that whether paste solder printing is qualified.The method has effectively improved paste solder printing accuracy of detection problem.The measurement mechanism arranging for realizing the inventive method, simple in structure easy to operate, be beneficial to the realization of N step mensuration.
Accompanying drawing explanation
Fig. 1 is principle of triangulation figure;
Fig. 2 is deforming stripe image;
Fig. 3 is measuring method process flow diagram;
Fig. 4 is measurement mechanism front view;
Fig. 5 is measurement mechanism lateral plan;
Fig. 6 is measurement mechanism vertical view;
Fig. 7 is measurement mechanism stereographic map;
Fig. 8 is that view is disassembled in measurement mechanism part;
Fig. 9 is the primary structure cut-open view of grating assembly.
Embodiment
Below in conjunction with drawings and Examples, the present invention is described in detail.
For tin cream is comprised area, center, highly, the three-dimensional measurement of the aspect such as volume, shape, the measurement data that we need to obtain most critical is exactly the height of each point on tin cream.The altitude information of comprehensive each pixel, just can further obtain the area, center of tin cream, highly, the three-dimensional data such as volume, shape, according to above data, just can judge that whether tin cream qualified.
In order to obtain altitude information, the present invention has utilized triangulation, principle as shown in Figure 1:
In Fig. 1, establish: R is reference field, C is sampling camera, P is grating (so-called grating, in fact on a clear glass, engrave exactly many equidistant wide grooves, while making light see through this glass to project, can form overleaf light and dark striated projection); Camera C and grating P are in same level, and the horizontal range between photocentre is D, and the vertical projection point of camera C photocentre on reference field R is O, and the vertical range of photocentre and reference field is L; Establish: H is the object point that needs measuring height, the vertical projection point of H on reference field R is H ', HH '=h again; The intersection point of the extended line of grating P photocentre and H line on reference field R is A, and the intersection point of the extended line of camera C photocentre and H line on reference field R is B.
From Fig. 1, can apparently find out, two triangle HBA and HCP are similar triangles, and in order to try to achieve object point H apart from the height h of reference field R, we can utilize the relation of two similar triangles:
h/L＝AB/(AB+D)
From above formula, derive, we can know:
h＝L*AB/(AB+D) (1)
Because L and D are hardware system structure parameter, after completing, Standard can demarcate acquisition.Therefore,, in order to obtain the height h of object point H, we only need to be by obtaining the length of AB someway.
In order to obtain AB length, we utilize the N step phase-shift method (being also called PMP algorithm) based on Moire fringe projection, it is measured, algorithm principle as shown in Figure 2:
In Fig. 1, P1 and P2 are entrance pupil and the emergent pupils of optical projection system (being grating P), and I1 and I2 are entrance pupil and the emergent pupils of imaging system (being camera C).When sinusoidal grating template is broken while projecting to three-dimensional diffuse reflection body surface, the deforming stripe picture of observing as shown in Figure 2, can be formulated as:
I(x，y)＝A(x，y)+B(x，y)*cosφ(x，y)] (2)
In above formula, I (x, y) represents the light intensity of the object point that planimetric coordinates is (x, y), A (x, y) be background intensity, B (x, y)/A (x, y) be fringe contrast, phase function φ (x, y) represents the striped distortion causing due to object surface shape, thereby comprises testee elevation information.About phase function φ (x, y) can so understand: after optical grating projection, the striped obtaining on object is a sine streak, that is to say, along the direction perpendicular to striped, light intensity becomes Sine distribution, so-called fringe period, be exactly that light intensity is from the brightest to next time the brightest distance along striped vertical direction.Take any point on this vertical line is reference point, and other points just represent by function phi (x, y) position of this reference point relatively mutually so.
So-called N step phase-shift method, is exactly that the every transverse shifting of projection grating (with striped vertical direction) walks to n/N, just produces new deforming stripe as I
n(x, y):
I
n(x，y)＝A
n(x，y)+B
n(x，y)*cos[φ
n(x，y)] (3)，
Continuous moving and obtain K frame (3≤K≤N) deforming stripe picture, thus can distribute mutually in the hope of the position of this point:
φ(x，y)＝arctg{[∑I
n(x，y)*sin(2πn/N)]/[∑I
n(x，y)*cos(2πn/N)]} (4)。
(3), in (4) formula, n=1 ... K, 3≤K≤N, I
n(x, y) is that grating moves to the x that n step obtains, and the light intensity that y is ordered directly gets after can taking pictures from image; A
n(x, y), B
n(x, y) is constant, so from above formula, can be in the hope of φ (x, y).
For N step phase shift algorithm, at every turn necessary mobile 1/N, such as four-step phase-shifting, so each grating all moves 1/4.
The position phase distribution phi (x, y) being calculated by above formula, due to the character of inverse trigonometric function, can be truncated within the scope of its main value, ± k π place discontinuous (K is natural number), so must use unwrapping algorithm can recover the original continuous distribution form of φ (x, y).
So-called parcel, is also a position phase convolution, refers to when object surpasses a fringe period with respect to the height of reference field, there will be many stripeds to squeeze situation about cannot distinguish at a place, thus an impact calculating mutually.At this time, just need to the position of each point be reverted to reasonable interval mutually by certain algorithm.The unwrapping algorithm that we adopt is exactly: the striped phase change that supposition object height causes, can not surpass a fringe period (namely the present invention implies a restriction: can not measuring height over the object of fringe period), so, we try to achieve deforming position phase φ (x by above formula, y) afterwards, (initial bit is exactly the position phase φ of object point to be measured subpoint on reference field mutually to understand the initial bit phase of using φ (x, y) to deduct this point
0(x, y), the position phase while being equivalent to this object point height and being zero), and require within the scope of arrive+π of must drop on-π of this phase differential.If once discovery phase differential is super, gone beyond the scope, we will add or deduct one-period π by deforming position phase φ (x, y) automatically, until meet restriction.
According to the structural parameters of system itself, can calculate the position of space light field in reference planes and distribute mutually, set up reference planes coordinate R (x, y) and initial bit phase φ
0mapping relations between (x, y), by these mapping relations with the form of tables of data be stored in standby in computing machine can (foundation of mapping table also can be determined by a reference plane is carried out to actual measurement).
In real work, we just can obtain φ (x, y) according to planimetric coordinates R (x, y) by formula (4), and then try to achieve AB and h.By φ (x, y), further ask the method for AB to be:
1) first allow grating upper mobile at reference field R (being a plane), obtain N width plane deformation striped picture, thereby according to above formula (4), can put in the hope of determinand the initial bit phase φ of H
0(x, y), wherein R (x, y) is the planar coordinate of object point H vertical projection on reference field R;
2) on reference field R, place (in determinand, comprise is highly the object point H to be measured of h) after determinand, moving grating, obtains N width deforming stripe picture, thereby according to above formula (4), can be in the hope of being highly the deforming position phase φ of the object point H of h
h(x, y);
3), according to above two steps, can obtain the phasic difference φ that object point H produces after height change
h(x, y)-φ
0(x, y);
4) striped obtaining due to us similarly is sine streak, that is to say, and phase change one-period, the plan range causing is changed to 2 π, so when phase change is φ
h(x, y)-φ
0when (x, y), it is exactly AB=[φ that the plan range producing changes
h(x, y)-φ
0(x, y)] * p/ (2 π) (namely plan range AB), wherein p is the fringe period that projection obtains, and is also system constant, after Standard completes, demarcates and can obtain;
5) obtain after AB, can try to achieve the height h of object point H according to formula (1).
Actual measuring process, we can embody by process flow diagram 3.
1) measuring system is in place, connects computing machine, and each calibrating parameters is definite, prepares to start;
2) system is positioned at origin position (origin position is exactly the grating working position of ceramic motor input voltage while being 0V, the principle of work of pottery motor is, according to the magnitude of voltage of input, grating produces corresponding in-plane displancement), camera looks like to take pictures to origin position deforming stripe, be stored in computing machine, the detection software in computing machine carries out subsequent treatment to image;
3) control the n/N position that ceramic motor driving lenticular lenses moves to the grating cycle, n=1... (N-1), once, camera all looks like to take pictures to deforming stripe in every movement, at least gets continuous three shooting results storage;
4) utilize N step phase-shift method, try to achieve the deforming position phase of each pixel in image, comprising the deforming position phase of object point H to be measured;
5) deforming position phase and initial bit are compared mutually, obtain distance A B (initial bit mutually reality is also to adopt N step phase-shift method to record, in advance the mapping relations table of memory plane coordinate and initial bit phase in computing machine);
6), according to triangulation formula, calculate the height h of object point to be measured;
7) altitude information of other pixels on comprehensive determinand, just can obtain the three-dimensional datas such as height, area, center, volume, shape of tin cream;
8), according to above data, judge that whether tin cream is qualified.
In the process of calculating pixel point height, because grating is oblique projection (the present invention use sinusoidal grating or Ronchi grating can), so can form at body surface the optical effect of similar mirror-reflection and shadow region, thereby affect the degree of accuracy of phase measurement.We can be in conjunction with the measurement results of many group gratings, and obtain weighted mean value according to weight, and actual measured results is multiplied by weighted mean value, can obtain so the comparatively conclusion of science, effectively avoid the optical problem such as reflective, shade.
Therefore,, in order to realize N step phase-shift method, the present invention adopts and measures with lower device:
As shown in Fig. 4～8, a work in combination platform 1, is fixed with camera support 2 and grating erecting frame 3 on it.On camera support 2 and grating erecting frame 3, can be fixed with camera 4 and grating assembly 5 respectively change location.Wherein camera 4 has one to be enough to, and 5 of grating assemblies can arrange many groups.
Further, camera support 2 comprises that one is fixed on the column 21 on worktable 1, longitudinally arranges on two row's bolt hole 22, two row's bolts hole 22 and be bolted a camera slide block 23 on column 21, and described camera 4 is installed on camera slide block 23.Because bolt hole 22 is a plurality of, so the position of conversion camera slide block 23 on bolt hole just can in a disguised form regulate the height of camera 4 on camera support 2, what is called can be fixed change location.
Or, two slide rails are set on column 21, camera slide block 23 is slidedly arranged on described slide rail, and drives connection by the motor being fixed on column.When camera slide block 23 slides along slide rail, camera 4 also moves thereupon, thus conversion height.
Grating erecting frame 3 can be to comprise that one is fixed on the column on worktable 1, and a grating framework 31 is installed on column, and on grating framework, level is installed described grating assembly 5, and grating assembly 5 can move horizontally on grating framework 31.When having many group grating assemblies 5, set up a plurality of columns and a plurality of grating framework, a grating assembly of a corresponding installation of grating framework, the mounting means of grating framework on column can be taked the mounting means between two kinds of camera supports 2 as above and camera 4, is height variable position and fixes (in Fig. 4～8 not depending on going out this structure).
As shown in Fig. 4,7, more preferably, grating erecting frame 3 can be installed by means of column 21, now grating erecting frame 3 is the same with camera slide block 23, also be can fix on column 21 by bolt hole 22 or slide rail, camera slide block 23 goes to upper and lower position with grating erecting frame 3 and arranges on column change location.In grating erecting frame 3 top sets, go out a plurality of grating frameworks 31, on each grating framework 31 for a grating assembly 5 is installed.
As shown in Figure 8, in grating framework 31 inside, be provided with two grating slide rails 14, along tending to/be away from the direction setting at device center; In the centre position of two grating slide rails 14, be provided with camera aperture 32.Grating slide rail 14 is provided with grating slide block 6, and grating slide block 6 is driven by the ceramic motor 13 being fixed on motor mount 12.Grating assembly 5 has comprised a grating installing plate 7 being fixed on grating slide block 6, is fixed with lenticular lenses 8 on grating installing plate 7, and lenticular lenses 8 is covered on camera aperture 32; In the installation of camera aperture part below 32 is an optical grating projection camera lens 9.Grating assembly 5 has also comprised a grating protective cover 10, is located on grating framework 31, and the grating slide rail 14 by grating framework more than 31, grating slide block 6, grating installing plate 7, lenticular lenses 8 are all protected inside.At grating protective cover 10 center, also there is a light source hole 15, at the top of light source hole 15, lay source of parallel light 11.
Using method about this device is:
1, first measurement datum R is placed on to whole device below, makes can obtain striped picture clearly on reference field R;
2, open source of parallel light 11;
3, computer control software sends voltage 0V, drives ceramic motor 13 to get back to origin position, thereby drives the lenticular lenses 8 on grating slide block 6 to get back to reference position;
4, use camera 4 to take pictures, and the software that the image of taking acquisition is sent in computing machine is stored simultaneously;
5, control software and send again suitable magnitude of voltage, drive ceramic motor 13 to travel forward for 1/5 cycle (supposing will be divided into 5 steps the cycle in this embodiment), thereby drive the lenticular lenses 8 on grating slide block 6 to move forward for 1/5 cycle;
6, use camera 4 to take pictures, and the software that the image of taking acquisition is sent in computing machine is stored simultaneously;
7, continue to control software and send suitable voltage, drive ceramic motor 13 to travel forward again for 1/5 cycle, thereby drive the lenticular lenses 8 on grating slide block 6 also to continue to move forward 1/5 cycle;
8, use camera 4 to take pictures, and the software that the image of taking acquisition is sent in computing machine is stored simultaneously;
9, so according to 5-6 step, (or the mode cycling of 7-8 step moved forward for 1/5 cycle at every turn, until moved to for the 4/5th cycle, mobilely all used camera 4 to take pictures at every turn, and stored taking the software that the image that obtains sends in computing machine;
10,, in five photos that obtain in above step 3-10, computing machine extracts respectively the grey scale pixel value I of same point (x, y)
n(x, y), i.e. light intensity value;
11, by five groups of light intensity value I
n(x, y) substitution formula (4), the initial bit phase φ of the acquisition object point H of plane place (x, y)
0(x, y), this process is completed by computing machine;
12, the thing to be measured with certain altitude (height can not surpass the determinand deforming stripe cycle) is placed on the reference field R of whole device below;
13, same according to the operation of above-mentioned 211 steps, calculate the deforming position phase φ that object point H produces before and after height change
h(x, y), this process is completed by computing machine;
14, the deforming position phase φ 13 steps being obtained
hthe initial bit phase φ that (x, y) and 11 steps obtain
0(x, y) does and subtracts, and obtains the phasic difference φ that height change produces
h(x, y)-φ
0(x, y), this process is completed by computing machine;
15, the striped obtaining due to us similarly is sine streak, that is to say, and phase change one-period, the plan range causing is changed to 2 π, so work as phase change, is φ
h(x, y)-φ
0when (x, y), it is exactly [φ that the plan range producing changes
h(x, y)-φ
0(x, y)] * p/ (2 π), plan range AB namely, wherein p is the fringe period that projection obtains, and is also system constant, this process is completed by computing machine;
16, obtain after AB, can according to formula (1), try to achieve the height h of object point H, this process is completed by computing machine.
Claims (6)
1. a three-dimensional body measuring method, is characterized in that, comprises the steps:
1) be provided with the measurement mechanism that comprises sample camera, light source and moving grating, the parameters of measurement mechanism is demarcated in advance, and the sampling camera ceramic motor used with moving grating is connected with computing machine;
2) measurement datum is placed on to device below, makes can obtain striped picture clearly on reference field;
3) open light source, control ceramic motor and make grating move to origin position, camera looks like to take pictures to the deforming stripe of origin position, is stored in computing machine;
4) control the n/N position that ceramic motor driving grating moves to fringe period successively, n=1... (N-1), once, camera all looks like to take pictures to deforming stripe and is stored in computing machine in every movement;
5) in each photos obtaining, computing machine extracts respectively the grey scale pixel value I of same pixel (x, y)
n(x, y), i.e. light intensity value, and utilize N step phase-shift method, try to achieve the initial bit phase φ of this pixel
0(x, y); The initial bit of other pixels is also tried to achieve with same method mutually;
6) determinand with certain altitude is placed on reference field, makes can obtain striped picture clearly on determinand;
7) equally according to above-mentioned 3)-6) operation of step, utilizes N step phase-shift method to try to achieve the deforming position phase φ that determinand and corresponding pixel points on reference field produce after height change
h(x, y);
8) utilize formula AB=[φ
h(x, y)-φ
0(x, y)] * p/ (2 π), the plan range of trying to achieve this pixel changes, and wherein p is the fringe period that projection obtains, and is system constant;
9) according to triangulation formula: h=L*AB/ (AB+D), calculate the height h of this pixel, wherein L be camera photocentre to the vertical range of reference field, D is the horizontal range between camera and grating photocentre;
10) utilize 7)-9) computing method of step, try to achieve the height of other pixels of determinand, the altitude information of each pixel on comprehensive determinand, just can obtain the three-dimensional datas such as height, area, center, volume, shape of determinand;
11), according to three-dimensional datas such as the height of determinand, area, center, volume, shapes, judge that whether tin cream is qualified;
Wherein, described N step phase-shift method, refers to: when optical grating mold plate is projected to three-dimensional diffuse reflection body surface, the deforming stripe picture of observing, is formulated as:
I(x，y)＝A(x，y)+B(x，y)*cos[φ(x，y)] (1)
(1), in formula, I (x, y) represents that planimetric coordinates is (x, the light intensity of object point y), A (x, y) is background intensity, B (x, y)/A (x, y) be fringe contrast, phase function φ (x, y) represents the striped distortion causing due to object surface shape, when grating is along often move to n/N step perpendicular to stripe direction, just produce a deforming stripe as I
n(x, y):
I
n(x，y)＝A
n(x，y)+B
n(x，y)*cos[φ
n(x，y)] (2)
Continuous moving and obtain K frame deforming stripe picture, thus can be in the hope of the deforming position phase φ (x, y) of this point:
φ(x，y)＝arctg{[∑I
n(x，y)*sin(2πn/N)]/[∑I
n(x，y)*cos(2πn/N)]} (3)
(2), in (3) formula, n=1 ... K, 3≤K≤N, A
n(x, y) is background intensity, B
n(x, y)/A
n(x, y) is fringe contrast, so from above formula, can be in the hope of φ (x, y).
2. three-dimensional body measuring method according to claim 1, is characterized in that, the height of described determinand is less than the fringe period of its grating distortion.
3. three-dimensional body measuring method according to claim 1, is characterized in that, described reference field is a plane.
4. three-dimensional body measuring method according to claim 1, is characterized in that, described moving grating can be for a plurality of, measurement result in conjunction with a plurality of gratings, according to weight, obtain weighted mean value, actual measured results is multiplied by weighted mean value, obtain actual measurement height.
5. three-dimensional body measuring method according to claim 1, is characterized in that, described moving grating is sinusoidal grating or Ronchi grating.
6. three-dimensional body measuring method according to claim 1, it is characterized in that, in N step phase-shift method, the deforming position phase φ (x being calculated by formula (2), (3), y), must use unwrapping algorithm to recover original continuous distribution form, use φ (x, y) deduct the initial bit phase of this point, and require within the scope of arrive+π of must drop on-π of this phase differential, if discovery phase differential is super, go beyond the scope, just automatically by deforming position phase φ (x, y) add or deduct one-period π, until meet restriction.
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| CN201310024956.0A CN103047944B (en) | 2013-01-22 | 2013-01-22 | Three-dimensional object measuring method and device |
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| CN105486245A (en) * | 2015-11-19 | 2016-04-13 | 中国航空工业集团公司北京航空材料研究院 | Experimental device and method for measuring depression depth of composite material after impact |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5450204A (en) * | 1992-03-30 | 1995-09-12 | Sharp Kabushiki Kaisha | Inspecting device for inspecting printed state of cream solder |
| CN1483999A (en) * | 2003-08-15 | 2004-03-24 | 清华大学 | Method and system for measruing object two-dimensiond surface outline |
| CN101451826A (en) * | 2008-12-17 | 2009-06-10 | 中国科学院上海光学精密机械研究所 | Object three-dimensional contour outline measuring set and measuring method |
| CN102155924A (en) * | 2010-12-17 | 2011-08-17 | 南京航空航天大学 | Four-step phase shifting method based on absolute phase recovery |
| CN202126246U (en) * | 2011-05-17 | 2012-01-25 | 东莞市神州视觉科技有限公司 | Fast three-dimensional measuring system for patch printing solder pastes |
-
2013
- 2013-01-22 CN CN201310024956.0A patent/CN103047944B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5450204A (en) * | 1992-03-30 | 1995-09-12 | Sharp Kabushiki Kaisha | Inspecting device for inspecting printed state of cream solder |
| CN1483999A (en) * | 2003-08-15 | 2004-03-24 | 清华大学 | Method and system for measruing object two-dimensiond surface outline |
| CN101451826A (en) * | 2008-12-17 | 2009-06-10 | 中国科学院上海光学精密机械研究所 | Object three-dimensional contour outline measuring set and measuring method |
| CN102155924A (en) * | 2010-12-17 | 2011-08-17 | 南京航空航天大学 | Four-step phase shifting method based on absolute phase recovery |
| CN202126246U (en) * | 2011-05-17 | 2012-01-25 | 东莞市神州视觉科技有限公司 | Fast three-dimensional measuring system for patch printing solder pastes |
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