CN103411544A - Photodiode encoding disc and object relative displacement measurement method by using photodiode encoding disc - Google Patents

Abstract

The invention relates to a photodiode encoding disc and an object relative displacement measurement method by using the photodiode encoding disc and belongs to the technical field of measurement. The photodiode encoding disc of the invention comprises a laser receiving plate and a laser emitting device. The photodiode encoding disc is characterized in that the laser receiving plate is composed of a diode encoding disc 1 and a diode encoding disc 2; one end of the diode encoding disc 1 and one end of the diode encoding disc 2 are fixed in a manner that one end of the diode encoding disc 1 and one end of the diode encoding disc 2 are vertical to each other; the diode encoding disc 1 is consistent with the diode encoding disc 2 in size, structure and function; the diode encoding disc 1 is composed of a photodiode array in n lines and n columns; n photodiodes are arranged in each line, and n photodiodes are arranged in each column, wherein the n is a positive odd number which is larger than 1; photodiodes in each line are on the same straight line; photodiodes each column are on the same straight line; each line of photodiodes is parallel to each other; each column of photodiodes is parallel to each other; straight lines formed by each line of photodiodes and straight lines formed by each column of photodiodes are perpendicular to each other; the interval between each line of photodiodes and the interval between each column of photodiodes is m millimeter, wherein m is greater than 0; the laser emitting device is composed of two laser heads; and one end of one laser head and one end of the other laser head are vertical to each other.

Description

The method of the relative displacement of a kind of photodiode code-disc and measurement object thereof

Technical field

The present invention relates to a kind of photodiode code-disc and measure the method for the relative displacement of object, belong to field of measuring technique.

Background technology

Along with bridge, occupy the status become more and more important in communications and transportation, the continuous progress of Bridge Design theory and operating technique makes bridge span that new breakthrough constantly be arranged, and version is also increasingly sophisticated.Be not only the traditional railway bridge, domestic high ferro is also in building on a large scale.Bridge in use can be subject to the factors such as increase, environmental load, reinforcement corrosion, freeze thawing damage, alkali, fatigue effect, damage accumulation, corrosion effect and material aging of external environment such as volume of transport, inevitably make the stability be connected between each member of bridge reduction, structural-load-carrying capacity decline, drag decay, permanance reduction etc. problem, these sum up the variation that can be expressed as each member relative position.So the safety monitoring of the heavy constructions such as bridge should come into one's own gradually.

What existing detection method adopted mostly is manually to carry out regular visit, and drawback one is the real-time measurement that can't guarantee measured object, and continuous data can't be provided; Drawback two is that manual inspection can't record the accumulation that relative position changes.Therefore, we are in the urgent need to a kind of easy, monitoring method of accurately, not needing manual intervention.

Summary of the invention

The present invention is directed to the proposition of above problem, and develop a kind of photodiode code-disc and measure the method for the relative displacement of object.The present invention proposes a kind of simply and accurately to the method for the heavy construction safety monitorings such as bridge.Not only can realize the monitoring of real-time on-site, and the accumulation that the relative position between each member changes can be carried out to record.By the data that collect, also can carry out suitable early warning analysis and maintenance work simultaneously.

Technological means of the present invention is as follows:

A kind of photodiode code-disc, comprise the laser pick-off plate and send out laser aid; The laser pick-off plate consists of diode code-disc one and diode code-disc two, one end of diode code-disc one and diode code-disc two is mutually vertical fixing, the size structure function of diode code-disc one and diode code-disc two is consistent, and diode code-disc one is comprised of the photodiode array of the capable n row of n; Every row arranges n photodiode, and every row arrange n photodiode, and n is greater than 1 positive odd number; The photodiode of every row and every row all is on same straight line and each row and column are parallel to each other, and the straight line that the photodiode of every row and every row forms is mutually vertical, every row and every row be spaced apart the m millimeter, m is greater than 0; Send out laser aid and consist of two laser heads, an end of two laser heads is vertical the setting mutually; Laser pick-off plate and a laser aid are arranged on different stiff ends; Diode code-disc one and diode code-disc two external power supplys; The position of laser pick-off plate and a laser aid is arranged on different positions; The laser pick-off plate is arranged on the object of the position change of wanting tested; Send out laser aid and be arranged on static position, the laser beam vertical irradiation that two laser heads of original state send is on the photodiode of (n+1)/2 row of diode code-disc one and diode code-disc two (2) and (n+1)/2 row; The laser pick-off plate connects computing module.

The intersection point of (n+1)/2 row (n+1)/2 of the capable n row of n diode code-disc one row is set to initial point and sets up two-dimensional coordinate system, (n+1)/2 row is set to coordinate system x axle, and (n+1)/2 row are set to coordinate system y axle; Photodiode to the capable n row of the n of diode code-disc one (1) carries out set positions, from first photodiode in the lower left corner, starting from top to bottom number consecutively is 1 to n to mean line number, from left to right number consecutively 1 to n means row number, and n is greater than 1 positive odd number; The photodiode positions of (n+1)/2 row (n+1)/2 row is for setting coordinate (0,0), the photodiode positions of (n+1)/2 row ((n+1)/2)+1 row is (m, 0), the photodiode positions of (n+1)/2 row ((n+1)/2)-1 row is (m, 0); With this rule, set the diode location of each photoelectricity, namely the diode location of the photoelectricity of the capable k row of s is ((k-(n+1)/2) m, (s-(n+1)/2) and m), s, k is less than or equal to n; When changing, laser pick-off plate stationary device position can drive the change in location of laser pick-off plate, the position of the initial reception laser beam of diode code-disc one can change thereupon like this, receives the change that the laser beam position change can be embodied in the diode of the photoelectricity that receives laser; When should laser pick-off plate stationary device position changing, the position of the initial reception laser beam of diode code-disc two can change thereupon, and diode code-disc two receives the change that the laser beam position changes can be embodied in the diode of the photoelectricity that receives laser; By the algorithm of computing module, can obtain the relative position change of measured object.

The algorithm of computing module is achieved as follows:

Suppose that in use procedure, diode code-disc one at the photodiode coordinate that n receives laser spots constantly is

B′ _n＝(x′ _n,y′ _n)， （1）

(x ' _n, y ' _n) represent that photodiode is the photodiode of the capable k row of s at the position coordinates of diode code-disc one, (x ' _s, y ' _k)=(k-(n+1)/2) m, (s-(n+1)/2) m);

The photodiode coordinate that n+1 receives the point of laser constantly is

B′ _n+1＝(x′ _n+1,y′ _n+1)， （2）

(x ' _N+1, y ' _N+1) represent that photodiode is the photodiode positions of the s ' row k ' row at the position coordinates of diode code-disc one,

(x′ _s,y′ _k)=((k′－(n+1)/2)m,(s′－(n+1)/2)m)，

On diode code-disc one (1) plane, receive the vector of the point of laser

$\stackrel{\→}{d_x}=\stackrel{\→}{B_n^{\′}{B}_{n+1}^{\′}}=[(x_{n+1}^{\′}-x_n^{\′}),(y_{n+1}^{\′}-y_n^{\′})],---\left(3\right)$

With formula (1) (2) (3) in like manner, diode code-disc two at the photodiode coordinate that n receives laser spots constantly is

B′′ _n＝(y′′ _n,z′′ _n)，

(y ' ' _n, z ' ' _n) represent that photodiode is the photodiode positions of the capable k row of s at the position coordinates of diode code-disc two,

(y′′ _n,z′′ _n)=((k－(n+1)/2)m,(s－(n+1)/2)m)，

The photodiode coordinate that n+1 receives laser spots constantly is

B′′ _n+1＝(y′′ _n+1,z′′ _n+1)，

(y ' ' _N+1, z ' ' _N+1) represent photodiode the position coordinates of diode code-disc two namely the photodiode coordinate of the s ' row k ' row be,

(y′′ _n+1,z′′ _n+1)=((k′－(n+1)/2)m,(s′－(n+1)/2)m)，

On diode code-disc two planes, receive the vector of the point of laser

$\stackrel{\→}{d_y}=\stackrel{\→}{B_n^{\′\′}{B}_{n+1}^{\′\′}}=[(y_{n+1}^{\′\′}-y_n^{\′\′}),(z_{n+1}^{\′\′}-z_n^{\′\′})],$

The displacement be located in diode code-disc one is D _x,

$D_x=\left|\stackrel{\→}{B_n^{\′}{B}_{(n+1)}^{\′}}\right|=\sqrt{{(x_{(n+1)}^{\′}-x_n^{\′})}^2+{(y_{(n+1)}^{\′}-y_n^{\′})}^2}$

$=\sqrt{((k^{\′}-(n+1)/2)m-(k-(n+1)/2)m{)}^2-{((s^{\′}-(n+1)/2)m-(s-(n+1)/2)m)}^2,}$

Displacement at diode code-disc (2) is D _y

$D_y=\left|\stackrel{\→}{B_n^{\′\′}+B_{n+1}^{\′\′}}\right|=\sqrt{{(y_{n+1}^{\′\′}-y_n^{\′\′})}^2+{(z_{n+1}^{\′\′}-z_n^{\′\′})}^2},$

$=\sqrt{((k^{\′}-(n+1)/2)m-(k-(n+1)/2)m{)}^2-{((s^{\′}-(n+1)/2)m-(s-(n+1)/2)m)}^2}.$

Ultimate principle of the present invention and beneficial effect:

The laser pick-off plate consists of diode code-disc one and diode code-disc two, one end of diode code-disc one and diode code-disc two is mutually vertical fixing, the size structure function of diode code-disc one and diode code-disc two is consistent, and diode code-disc one is comprised of the photodiode array of the capable n row of n; Every row arranges n photodiode, and every row arrange n photodiode, and n is greater than 1 positive odd number; The photodiode of every row and every row all is on same straight line and each row and column are parallel to each other, and the straight line that the photodiode of every row and every row forms is mutually vertical, every row and every row be spaced apart the m millimeter, m is greater than 0; M is measuring error, and m can adjust size according to actual needs.

When the buildings such as observation bridge, because their each members are positioned at same tectonic plates substantially.

If observe the change conditions of two interface components A and the B of a building, just need the spatial reference point O of an absolute rest.As Fig. 1, suppose that the O point is an absolute reference point in space, A, B be respectively on two members of measured object each a bit.The O point of take is set up the space spheric coordinate system as initial point, and the coordinate of establishing you the n moment A, B is followed successively by

(n+1) A, B respective coordinates are constantly

N constantly with (n+1) constantly

Be followed successively by

Order

$\stackrel{\→}{D}=\stackrel{\→}{{\mathrm{AB}}_{n+1}}-{\stackrel{\→}{\mathrm{AB}}}_n,---\left(5\right)$

If

Illustrate that relative motion does not occur for A and B.Otherwise relative motion occurs in A and B.

The use of absolute reference point can the simplified measurement process and the analytical calculation of data, the method one that the absolute reference point is chosen is absolute reference to be put to O be chosen at the place apart from the measured object infinite distance, even L → ∞, but the size of L is inversely proportional to measuring accuracy, distance precision far away is poorer, causes measuring error excessive.Second method be by absolute reference put O and measured object from very close to, but so just can't guarantee the property independent of one another between the two, one shakes in a process of moving, correlativity is strong, the independence between each member is beyond expression of words, causes measurement data inaccurate.Therefore choosing of absolute reference point is a kind of perfect condition in engineering construction.

Therefore, how to design a kind of real-time not only simple but also can guarantee that the monitoring scheme of the precision of data just becomes a difficult problem.

The present invention is based on the photodiode code-disc and carry out the reception of signal, thereby the relative shift that changes into measured object carries out Real-Time Monitoring to the health status of each member of bridge and various large scale structure buildings.Simplify the method for measuring, and solved inaccuracy and the non real-time property of traditional measured data of manual inspection.

(1) three dimensions variation analysis

The performance of vibration has two kinds, a kind of be in space to shake a kind of be translation on plane.A, B 2 points are arranged on hypothesis space, if take A describes the motion conditions of B as reference point, we can pass through in conjunction with following formula (1) (2) (3) (4) Variation reflect the displacement of B.As shown in Figure 2, establish A point coordinate under the three dimensions spherical coordinate system and be (0,0,0), the B point coordinate is

θ is the subpoint B ' of B point on the xoy plane and the angle of X-axis,

Angle for L and Z axis.{。##.##1},

Can find out thus: the variables L under three-dimensional coordinate system, θ,

All can be by two-dimensional coordinate x, y, z means.

(2) two-dimensional space change record

By formula formula (6), known, for each change in displacement of measured object, the changes in coordinates that we can be decomposed into three planes to it is x ' o ' y ' plane, x ' o ' z ' plane and y ' o ' z ' plane.The change in location of measured object can accurately be expressed with any two planes wherein.

We utilize the photodiode code-disc to carry out the record of relative position in two-dimensional space.Two orthogonal code- discs 1,2 difference corresponding vertical laser instrument 1 and laser instrument 2 placed with it is installed below bridge floor.Two code-discs mean plane x ' o ' y ' and y ' o ' z ' successively.So just, the motion vector in three dimensions has been resolved into to the kinematic variables on two two dimensional surfaces.

By moments of vibration

From three dimensions, being decomposed into two Displacement Analysis on two dimensional surface, that is: B is projected as B ' on x ' o ' y ', is projected as B ' ' on y ' o ' z ' plane.Displacement on x ' o ' y ' horizontal plane is

Displacement on y ' o ' z ' vertical plane is

Can use

With

Mean take the change in location of A as reference point B.

(3) code-disc receives the corresponding relation between data and two-dimensional space amount

The code-disc that apparatus of the present invention are used is a photodiode array, is embedded with code translator, divides horizontal stroke, ordinate are arranged.By the coded system of single-chip microcomputer matrix keyboard, each photodiode is positioned.As shown in Figure 3, suppose that use procedure at the upper coordinate that constantly receives the point of laser at n of the code-disc (code-disc on x ' o ' y ' plane represents diode code-disc 1) on x ' o ' y ' plane is

B′ _n＝(x′ _n,y′ _n) （7）

N+1 constantly

B′ _n+1＝(x′ _n+1,y _′n+1) （8）

Displacement on x ' o ' y ' plane

${\stackrel{\→}{d}}_x=\stackrel{\→}{B_n^{\′}{B}_{n+1}^{\′}}=[(x_{n+1}^{\′}-x_n^{\′}),(y_{n+1}^{\′}-y_n^{\′})]---\left(9\right)$

With formula (7) (8) (9) in like manner, on the code-disc (code-disc on y ' o ' z ' plane represents diode code-disc two (2)) on y ' o ' z ' plane, have

B′′ _n＝(y′′ _n,z′′ _n) （10）

B′′ _n+1＝(y′′ _n+1,z′′ _n+1) （11）

$\stackrel{\→}{d_y}=\stackrel{\→}{B_n^{\′\′}{B}_{n+1}^{\′\′}}=[(y_{n+1}^{\′\′}-y_n^{\′\′}),(z_{n+1}^{\′\′}-z_n^{\′\′})]---\left(12\right)$

The displacement be located in x ' o ' y ' plane is Dx

$D_x=\left|\stackrel{\→}{B_n^{\′}{B}_{(n+1)}^{\′}}\right|=\sqrt{{(x_{(n+1)}^{\′}-x_n^{\′})}^2+{(y_{(n+1)}^{\′}-y_n^{\′})}^2}---\left(13\right)$

Displacement in y ' o ' z ' plane is Dy

$D_y=\left|\stackrel{\→}{B_n^{\′\′}{B}_{(n+1)}^{\′\′}}\right|=\sqrt{{(y_{(n+1)}^{\′\′}-y_n^{\′\′})}^2+{(z_{(n+1)}^{\′\′}-z_n^{\′\′})}^2}---\left(14\right)$

(3) discrete analysis and the precision discussion that mean of code-disc

On code-disc, any time a bit has a double discrete sense, one be heavily spatially discrete one be heavily in time discrete.

(1) discrete on space: because the volume size of diode self be can not ignore, therefore the code-disc that forms of alternately photodiode is a discontinuous plane anyhow, has caused the dispersion error.But it is can be received that the displacement that this error and bridge vibration produce is compared.

(2) temporal discrete: adopting the mode of sampling to take the data that code-disc receives, is also discrete because the uncontinuity of sampling causes monitoring in time.The natural vibration frequency of each bridge of set basis of sampling frequency is formulated sampling frequency.The difference that causes natural frequency due to the difference of bridge material, structure, therefore in engineering construction sampling frequency choose not identical yet.

The double discrete of code-disc caused measurement to have error.The method that reduces error has two kinds: the first, and due to the given volume of photodiode, so we must make code-disc and it is arranged thick and fast with the photodiode of small volume; The second, under the different prerequisite of bridge natural frequency, should guarantee that choosing of sampling frequency is greater than 8 times of bridge natural frequency, with this, reduce the discrete error caused of sample time.

Contrive equipment comprises laser beam emitting device and photodiode code-disc, as signal, occurs and receiving trap respectively.Sender unit is generating laser, and it can produce linear light beam and low-power consumption, high-effect luminous power output, stable performance, high conformity, long service life.Signal receiving device is the receiving screen that diode laser matrix forms, the photodiode array receiving screen is to utilize photodiode just characteristic of conducting when illumination is arranged, when receiving screen receives the laser that emitter launches, convert light signal to electric signal, thus make the photodiode conducting can by receive laser concrete photodiode location presentation out.It has and is quick on the draw, low-power consumption, the advantage such as performance is good, and the life-span is long.

In the device use procedure, the data that collect are divided into three kinds on wholly: i.e. transient data, average data and accumulation.Transient data is the vibration effect of a certain sampling time, but is regressor to a certain extent; Average accumulation is the total displacement variable that records the generation of vibration impact, be a kind of can not regressor; The mean value of the average data impact that to be whole vibration processes bring measured object.

(4) alarm mode

According to the above-mentioned three kinds of data that collect, following two kinds of alarm modes are taked in the early warning of this device:

(1) before device is installed, according to characteristics such as the structure of bridge, amounts of deflection, set the safe thresholding of code-disc, if receive the inswept discrete point of generating laser outside thresholding, report to the police.Type of alarm is for installing some thumpers or light-emitting device reminds to forbid that vehicle passes through bridge at end of the bridge.

(2) in the device use procedure, measured object is carried out to the real-time sampling analysis, all data upload that collect, to administrative center, then are carried out to the related works such as field value set and bridge inspection and maintenance through control data corporation.

Beneficial effect of the present invention: the present invention utilizes real-time health monitoring between a set of each member that is applicable to bridge and various large scale structure buildings of generating laser and photodiode code-disc design and the device of critical early warning.Monitoring method of the present invention is simple, the device simple installation, and the energy that monitoring device consumes is few, can guarantee for a long time normal operation, inaccurate and the non real-time property of the artificial visually examine's method before having avoided, can meet monitoring requirements round-the-clock, real-time on-site, the large error of resulting data precision is little.

The accompanying drawing explanation

Fig. 1 is ultimate principle key diagram of the present invention.

Fig. 2 is three-dimensional spatial analysis of the present invention.

Fig. 3 is the present invention program's schematic diagram.

Fig. 4 (a) is scheme of installation of the present invention.

Fig. 4 (b) is the local enlarged diagram of installing of Fig. 4 of the present invention (a).

Fig. 5 is that the present invention monitors process flow diagram.

Fig. 6 is the structure diagram of apparatus of the present invention.

Fig. 7 is diode code-disc one structure diagram of the present invention.

Embodiment

Monitor flow process as shown in Figure 5:

1. be in static the time when bridge, system is once sampled every 1s, the photodiode that now receives laser should be initial point place (i.e. (n+1)/2 row (n+1)/2 row place), when bridge floor shakes, code-disc shakes with bridge floor, and the diode coordinate that now receives laser changes.

2. after the photodiode coordinate that receives laser being detected and changing, wake equipment set up, start working.

3. after equipment is waken up, increase sample frequency, (such as 100 per seconds of sampling, concrete sample frequency will be according to the project organization of whole bridge, intrinsic vibration frequency is set, because we can't set sampling to synchronize with the vibrations of bridge floor, for bridge being shaken to process, portray out more clearly, we the bridge vibrations need to be arrived to the displacement maximum and the minimum moment of locating samples, we can be made as sample frequency the octuple to ten times of the intrinsic vibration frequency of bridge, to make the data that collected can comprehensively reflect the shock conditions of bridge as far as possible.）

4. after increase sample frequency, the data recording at every turn collected is got off, carry out data calculating by module, calculate the distance of certain photodiode that constantly receives laser and true origin place photodiode.The distance that calculates and the safe distance of bridge (safe distance by bridge construction after, the maximum vibration amplitude of the bridge that the physical property of estimating when bridge security evaluation is set is determined) are compared.

5. comparative result: preserve if this distance in the safe distance scope, only upload the data to control data corporation; If this distance exceeds safe range, start at once warning device.(warning device can be at equipment such as end of the bridge installation warning lights, reminds the staff to stop vehicle to continue to pass through bridge)

6. this process flow diagram is circulation process figure, in the time of by data upload, can proceed the work of data sampling.This project also has an advantage: some expendable displacements, in the process come into operation, often can occur in bridge, such as situation about causing due to loosened screw etc.(such as, in certain vibrations process, the vibrations of 5cm have occurred in bridge floor on certain direction of level, but have only recovered 4cm when recovering, and like this, just make bridge floor position in static that change has occurred.The photodiode coordinate that causes receiving laser in static is no longer (0,0).When this expendable displacement runs up to a certain degree, be a severe test to the safety of bridge.) this device can make monitoring to the displacement accumulation of bridge.

As shown in Figure 6: a kind of photodiode code-disc comprises the laser pick-off plate and sends out laser aid; The laser pick-off plate consists of diode code-disc 1 and diode code-disc 22, one end of diode code-disc 1 and diode code-disc 22 is mutually vertical fixing, the size structure function of diode code-disc 1 and diode code-disc 22 is consistent, and diode code-disc 1 is comprised of the photodiode array of the capable n row of n; Every row arranges n photodiode, and every row arrange n photodiode, and n is greater than 1 positive odd number; The photodiode of every row and every row all is on same straight line and each row and column are parallel to each other, and the straight line that the photodiode of every row and every row forms is mutually vertical, every row and every row be spaced apart the m millimeter, m is greater than 0; Send out laser aid and consist of two laser heads, an end of two laser heads is vertical the setting mutually; Laser pick-off plate and a laser aid are arranged on different stiff ends; Diode code-disc 1 and diode code-disc 22 external power supplys; The position of laser pick-off plate and a laser aid is arranged on different positions; The laser pick-off plate is arranged on the object of the position change of wanting tested; Send out laser aid and be arranged on static position, the laser beam vertical irradiation that two laser heads of original state send is on the photodiode of (n+1)/2 row of diode code-disc 1 and diode code-disc 22 and (n+1)/2 row; The laser pick-off plate connects computing module.

A kind of photodiode code-disc realizes measuring the method for the relative displacement of object: as shown in Figure 7: the intersection point of (n+1)/2 row (n+1)/2 row of the capable n row of n diode code-disc 1 is set to initial point and sets up two-dimensional coordinate system, (n+1)/2 row is set to coordinate system x axle, and (n+1)/2 row are set to coordinate system y axle; Photodiode to the capable n row of the n of diode code-disc 1 carries out set positions, and from first photodiode in the lower left corner, starting from top to bottom number consecutively is 1 to n to mean line number, and from left to right number consecutively 1 to n means row number, and n is greater than 1 positive odd number; The photodiode positions of (n+1)/2 row (n+1)/2 row is for setting coordinate (0,0), the photodiode positions of (n+1)/2 row ((n+1)/2)+1 row is (m, 0), the photodiode positions of (n+1)/2 row ((n+1)/2)-1 row is (m, 0); With this rule, set the diode location of each photoelectricity, namely the diode location of the photoelectricity of the capable k row of s is ((k-(n+1)/2) m, (s-(n+1)/2) and m), s, k is less than or equal to n; When changing, laser pick-off plate stationary device position can drive the change in location of laser pick-off plate, the position of the initial reception laser beam of diode code-disc 1 can change thereupon like this, receives the change that the laser beam position change can be embodied in the diode of the photoelectricity that receives laser; When should laser pick-off plate stationary device position changing, the position of the initial reception laser beam of diode code-disc 22 can change thereupon, and diode code-disc 22 receives the change that the laser beam position changes can be embodied in the diode of the photoelectricity that receives laser; By the algorithm of computing module, can obtain the relative position change of measured object.

The algorithm of computing module is achieved as follows:

Suppose that in use procedure, diode code-disc one (1) at the photodiode coordinate that n receives laser spots constantly is

B′ _n＝(x′ _n,y′ _n)， （1）

(x ' _n, y ' _n) represent that photodiode is the photodiode of the capable k row of s at the position coordinates of diode code-disc one (1), (x ' _s, y ' _k)=(k-(n+1)/2) m, (s-(n+1)/2) m);

The photodiode coordinate that n+1 receives the point of laser constantly is

B′ _n+1＝(x′ _n+1,y′ _n+1)， （2）

(x ' _N+1, y ' _N+1) represent that photodiode is the photodiode positions of the s ' row k ' row at the position coordinates of diode code-disc one (1),

(x′ _s,y′ _k)=((k′－(n+1)/2)m,(s′－(n+1)/2)m)，

On diode code-disc one (1) plane, receive the vector of the point of laser

${\stackrel{\→}{d}}_x=\stackrel{\→}{B_n^{\′}{B}_{n+1}^{\′}}=[(x_{n+1}^{\′}-x_n^{\′}),(y_{n+1}^{\′}-y_n^{\′})]---\left(3\right)$

With formula (1) (2) (3) in like manner, diode code-disc two (2) at the photodiode coordinate that n receives laser spots constantly is

B′′ _n＝(y′′ _n,z′′ _n)，

(y ' ' _n, z ' ' _n) represent that photodiode is the photodiode positions of the capable k row of s at the position coordinates of diode code-disc two (2),

(y′′ _n,z′′ _n)=((k－(n+1)/2)m,(s－(n+1)/2)m)，

The photodiode coordinate that n+1 receives laser spots constantly is

B′′ _n+1＝(y′′ _n+1,z′′ _n+1)，

(y ' ' _N+1, z ' ' _N+1) represent photodiode the position coordinates of diode code-disc two (2) namely the photodiode coordinate of the s ' row k ' row be,

(y′′ _n+1,z′′ _n+1)=((k′－(n+1)/2)m,(s′－(n+1)/2)m)，

On diode code-disc two (2) planes, receive the vector of the point of laser

$d_y=\left|\stackrel{\→}{B_n^{\′\′}+B_{n+1}^{\′\′}}\right|=[(y_{n+1}^{\′\′}-y_n^{\′\′}),(z_{n+1}^{\′\′}-z_n^{\′\′})],$

The displacement be located in diode code-disc one (1) is D _x,

$D_x=\left|\stackrel{\→}{B_n^{\′}{B}_{(n+1)}^{\′}}\right|=\sqrt{{(x_{(n+1)}^{\′}-x_n^{\′})}^2+{(y_{(n+1)}^{\′}-y_n^{\′})}^2}$

$=\sqrt{((k^{\′}-(n+1)/2)m(k-(n+1)/2){m)}^2-{((s^{\′}-(n+1)/2)m-(s-(n+1)/2)m)}^2},$

Displacement at diode code-disc (2) is D _y

$D_y=\left|\stackrel{\→}{B_n^{\′\′}+B_{n+1}^{\′\′}}\right|=\sqrt{{(y_{n+1}^{\′\′}-y_n^{\′\′})}^2+{(z_{n+1}^{\′\′}-z_n^{\′\′})}^2},$

$=\sqrt{{((k^{\′}-(n+1)/2)m-(k-(n+1)/2)m)}^2-{((s^{\′}-(n+1)/2)m-(s-(n+1)/2)m)}^2}.$

Below in conjunction with accompanying drawing 4(a) and Fig. 4 (b) the present invention is conducted further description.

As shown in Fig. 4 (a) and Fig. 4 (b): two vertical diode code-disc 1 and diode code-discs 22 of placing are installed at B point place under tested bridge floor; Bridge when vibration occurs due to the existence of natural reonant frequency, the variation that can produce an amplitude.If the maximal value changing value of measured point B amplitude is U, the damage brought for the vibration of avoiding device in use to be subject to bridge floor, therefore at bridge pier, apart from bridge floor U place, a support is installed, two orthogonal laser beam emitting device Tx1 are installed on support, Tx2, its beam emissions head rushes at respectively diode code-disc 1 and diode code-disc 22.

The vibration effect that produced by the risk factors such as load can be similar to compared to bridge floor to be ignored, therefore we do not consider self-vibration and the resonance situation of support and bridge floor in measuring process, suppose their relative bridge floor absolute rest, the absolute reference point while both having put A for measurement.

We can draw the space displacement amount of B in conjunction with formula (7)-(14)

$D=\sqrt{D_x^2+{\mathrm{<figure-callout\; id="2"\; label="D\; y"\; filenames="HDA00003512412900031.png,HDA00003512412900041.png"\; state="\{\{state\}\}">D</figure-callout>}}_y^{}},---\left(15\right)$

As can be known by following formula: if D _xWith D _yValue larger, prove that displacement D is larger, just the impact that brings of explanation vibration is larger, the potential safety hazard of measured object is just larger.

The sampling interval of photodiode receiving screen is associated with photoreceiver efficiency.We suppose the wakeup time of apparatus of the present invention be zero and the receiving efficiency of photodiode code-disc very high, as long as the light beam that emitter sends slips over code-disc, will be acquired.Rapid due to what vibrate, may on a time point, can on receiving screen, slip over one track by laser, and cause being described accurately.Therefore, adopt the method for sampling to carry out Collection and analysis to the related data of vibration.At a sample point, only record the position received at that time, utilize these discrete points to carry out real-time health monitoring and critical early warning to each member of bridge and various large scale structure buildings.In record data, also to carry out critical early warning.At device, install originally, can set a security domain,, outside security domain, report to the police when the coordinate position of sample point.This security domain is along with the accumulation of time and the displacement accumulation of generation of vibration are changed.

The present invention is not limited to above-mentioned embodiment, and any equivalent concepts or change in the technical scope that the present invention discloses, all classify protection scope of the present invention as.

Claims (3)

1. photodiode code-disc, comprise the laser pick-off plate and send out laser aid, it is characterized in that: the laser pick-off plate consists of diode code-disc one (1) and diode code-disc two (2), one end of diode code-disc one (1) and diode code-disc two (2) is mutually vertical fixing, the size structure function of diode code-disc one (1) and diode code-disc two (2) is consistent, and diode code-disc one (1) is comprised of the photodiode array of the capable n row of n; Every row arranges n photodiode, and every row arrange n photodiode, and n is greater than 1 positive odd number; The photodiode of every row and every row all is on same straight line and each row and column are parallel to each other, and the straight line that the photodiode of every row and every row forms is mutually vertical, every row and every row be spaced apart the m millimeter, m is greater than 0; Send out laser aid and consist of two laser heads, an end of two laser heads is vertical the setting mutually; Laser pick-off plate and a laser aid are arranged on different stiff ends; Diode code-disc one (1) and diode code-disc two (2) external power supplys; The position of laser pick-off plate and a laser aid is arranged on different positions; The laser pick-off plate is arranged on the object of the position change of wanting tested; Send out laser aid and be arranged on static position, the laser beam vertical irradiation that two laser heads of original state send is on the photodiode of (n+1)/2 row of diode code-disc one (1) and diode code-disc two (2) and (n+1)/2 row; The laser pick-off plate connects computing module.

2. a kind of photodiode code-disc according to claim 1 is realized the method for the relative displacement of measurement object, it is characterized in that: the intersection point of (n+1)/2 row (n+1)/2 of the capable n row of n diode code-disc one (1) row is set to initial point and sets up two-dimensional coordinate system, (n+1)/2 row is set to coordinate system x axle, and (n+1)/2 row are set to coordinate system y axle; Photodiode to the capable n row of the n of diode code-disc one (1) carries out set positions, from first photodiode in the lower left corner, starting from top to bottom number consecutively is 1 to n to mean line number, from left to right number consecutively 1 to n means row number, and n is greater than 1 positive odd number; The photodiode positions of (n+1)/2 row (n+1)/2 row is for setting coordinate (0,0), the photodiode positions of (n+1)/2 row ((n+1)/2)+1 row is (m, 0), the photodiode positions of (n+1)/2 row ((n+1)/2)-1 row is (m, 0); With this rule, set the diode location of each photoelectricity, namely the diode location of the photoelectricity of the capable k row of s is ((k-(n+1)/2) m, (s-(n+1)/2) and m), s, k is less than or equal to n; When changing, laser pick-off plate stationary device position can drive the change in location of laser pick-off plate, the position of the initial reception laser beam of diode code-disc one (1) can change thereupon like this, receives the change that the laser beam position change can be embodied in the diode of the photoelectricity that receives laser; When should laser pick-off plate stationary device position changing, the position of the initial reception laser beam of diode code-disc two (2) can change thereupon, and diode code-disc two (2) receives the change that the laser beam position change can be embodied in the diode of the photoelectricity that receives laser; By the algorithm of computing module, can obtain the relative position change of measured object.

3. a kind of photodiode code-disc according to claim 1 is realized the method for the relative displacement of measurement object, and it is characterized in that: the algorithm of computing module is achieved as follows:

Suppose that in use procedure, diode code-disc one (1) at the photodiode coordinate that n receives laser spots constantly is

B′ _n＝(x′ _n,y′ _n)， （1）

(x ' _n, y ' _n) represent that photodiode is the photodiode of the capable k row of s at the position coordinates of diode code-disc one (1), (x ' _s, y ' _k)=(k-(n+1)/2) m, (s-(n+1)/2) m);

The photodiode coordinate that n+1 receives the point of laser constantly is

B′ _n+1＝(x′ _n+1,y′ _n+1)， （2）

(x ' _N+1, y ' _N+1) represent that photodiode is the photodiode positions of the s ' row k ' row at the position coordinates of diode code-disc one (1),

(x′ _s,y′ _k)=((k′－(n+1)/2)m,(s′－(n+1)/2)m)，

On diode code-disc one (1) plane, receive the vector of the point of laser

$\stackrel{\&RightArrow;}{d_x}=\stackrel{\&RightArrow;}{B_n^{\&prime;}{B}_{n+1}^{\&prime;}}=[(x_{n+1}^{\&prime;}-x_n^{\&prime;}),(y_{n+1}^{\&prime;}-y_n^{\&prime;})],---\left(3\right)$

With formula (1) (2) (3) in like manner, diode code-disc two (2) at the photodiode coordinate that n receives laser spots constantly is

B′′ _n＝(y′′ _n,z′′ _n)，

(y ' ' _n, z ' ' _n) represent that photodiode is the photodiode positions of the capable k row of s at the position coordinates of diode code-disc two (2),

(y′′ _n,z′′ _n)=((k－(n+1)/2)m,(s－(n+1)/2)m)，

The photodiode coordinate that n+1 receives laser spots constantly is

B′′ _n+1＝(y′′ _n+1,z′′ _n+1)，

(y ' ' _N+1, z ' ' _N+1) represent photodiode the position coordinates of diode code-disc two (2) namely the photodiode coordinate of the s ' row k ' row be,

(y′′ _n+1,z′′ _n+1)=((k′－(n+1)/2)m,(s′－(n+1)/2)m)，

On diode code-disc two (2) planes, receive the vector of the point of laser

$\stackrel{\&RightArrow;}{d_y}=\stackrel{\&RightArrow;}{B_n^{\&prime;\&prime;}{B}_{n+1}^{\&prime;\&prime;}}=[(y_{n+1}^{\&prime;\&prime;}-y_n^{\&prime;\&prime;}),(z_{n+1}^{\&prime;\&prime;}-z_n^{\&prime;\&prime;})],$

The displacement be located in diode code-disc one (1) is D _x,

$\begin{array}{c}{D}_x=\left|\stackrel{\&RightArrow;}{B_n^{\&prime;}{B}_{(n+1)}^{\&prime;}}\right|=\sqrt{{(x_{(n+1)}^{\&prime;}-x_n^{\&prime;})}^2+{(y_{(n+1)}^{\&prime;}-y_n^{\&prime;})}^2}\\ =\sqrt{{((k\&prime;-(n+1)/2)m-(k-(n+1)/2)m)}^2-{((s\&prime;-(n+1)/2)m-(s-(n+1)/2)m)}^2}\end{array},$

Displacement at diode code-disc (2) is D _y

$\begin{array}{c}{D}_y=\left|\stackrel{\&RightArrow;}{B_n^{\&prime;\&prime;}{B}_{n+1}^{\&prime;\&prime;}}\right|=\sqrt{{(y_{n+1}^{\&prime;\&prime;}-y_n^{\&prime;\&prime;})}^2+{(z_{n+1}^{\&prime;\&prime;}-z_n^{\&prime;\&prime;})}^2}\\ =\sqrt{{((k\&prime;-(n+1)/2)m-(k-(n+1)/2)m)}^2-{((s\&prime;-(n+1)/2)m-(s-(n+1)/2)m)}^2}\end{array}.$

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