阅读说明：本技术 一种基于激光位移传感器的螺栓螺距测量装置及测量方法 (A kind of bolt pitch measurement device and measurement method based on laser displacement sensor ) 是由 杨炯 张健 梁杰 王帅普 崔松涛 于 2019-09-27 设计创作，主要内容包括：本发明提供一种基于激光位移传感器的螺栓螺距测量装置及测量方法,本发明首先利用激光位移传感器采集待测螺栓的轮廓信息以形成数据点集合；然后设定阈值将数据点集合中符合要求的数据点筛选后形成新的数据点集合；利用波峰提取算法提取波峰并对相邻波峰之间的距离进行计算；最后根据相邻波峰之间的距离得出螺距,本发明测量方式简单、效率高,而且,本发明在将新的数据点集合构建成数据点曲线并对该数据点曲线进行分段拟合,从而可提高本发明的测量精度。(The present invention provides a kind of bolt pitch measurement device and measurement method based on laser displacement sensor, and the invention firstly uses laser displacement sensors to acquire the profile information of bolt to be measured to form set of data points；Then given threshold will form new set of data points after data point satisfactory in set of data points screening；Wave crest is extracted using wave crest extraction algorithm and the distance between adjacent peaks are calculated；Finally screw pitch is obtained according to the distance between adjacent peaks, measurement method of the present invention is simple, high-efficient, moreover, the present invention new set of data points is built into data point curve and carries out piecewise fitting to the data point curve, so that measurement accuracy of the invention can be improved.)

1. a kind of bolt pitch measurement device based on laser displacement sensor, what is be connected including experimental bench (7), with host computer swashs Optical displacement sensor (4), the fixing axle (1) for installing laser displacement sensor (4) and multiple for placing bolt to be measured (5) V-block (6), the measuring device is for measuring the screw pitch of bolt to be measured (5), it is characterised in that: described in multiple V-block (6) is along the setting of the length direction interval of experimental bench (7) and bolt to be measured (5) is placed on multiple V-blocks (6) Top, fixing axle (1) is arranged along the vertical direction and the bottom end of fixing axle (1) connects by the way that fixed plate (8) and experimental bench (7) are fixed It connects, the top of fixing axle (1) is provided with column support (2), and laser displacement sensor (4) passes through sensor mounting plate (3) and vertical Column holder (2) is connected.

2. a kind of bolt pitch measurement device based on laser displacement sensor according to claim 1, it is characterised in that: The V-groove for placing bolt to be measured (5) is offered at the top of the V-block (6).

3. a kind of bolt pitch measurement device based on laser displacement sensor according to claim 1, it is characterised in that: The central axis of the fixing axle (1) is vertical with the plane where experimental bench (7).

4. a kind of measurement method of bolt pitch measurement device based on laser displacement sensor according to claim 1, Characterized by comprising the following steps: first with laser displacement sensor (4) acquire the profile information of bolt (5) to be measured with Form set of data points；Then given threshold will form new data point after data point satisfactory in set of data points screening Set；Wave crest is extracted using wave crest extraction algorithm and the distance between adjacent peaks are calculated；Finally according to adjacent peaks The distance between obtain screw pitch.

5. a kind of measurement method of bolt pitch measurement device based on laser displacement sensor according to claim 4, It is characterized by: data point set described in definition is combined into { Q_i(x_i,y_i), wherein 0 < i < 800mm, given threshold u, if y_i> U, point Q_i(x_i,y_i) storage is into new set of data points, to form new set of data points { P_i(x_i,y_i)}；

In new set of data points { P_i(x_i,y_i) in, if there is data point meets y_i>y_i-1And y_i>y_i+1, then will be satisfactory Data point is extracted as wave crest Q₁(x_i,y_i), if new set of data points { P_i(x_i,y_i) in distance between every two consecutive number strong point For fixed value q, then the distance between adjacent peaks can be acquired are as follows:Finally according to the distance between adjacent peaks Screw pitch that you can get it.

6. a kind of measurement method of bolt pitch measurement device based on laser displacement sensor according to claim 5, It is characterized by: forming new set of data points { P_i(x_i,y_i) after, it is further comprising the steps of: by new set of data points {P_i(x_i,y_i) be built into data point curve and piecewise fitting is carried out to the data point curve.

7. a kind of measurement method of bolt pitch measurement device based on laser displacement sensor according to claim 6, It is characterized by: using B-spline curves fitting algorithm piecewise fitting when carrying out piecewise fitting to data point curve.

Technical field

The invention belongs to bolt pitch measurement technical fields, and in particular to a kind of bolt spiral shell based on laser displacement sensor Away from measuring device and measuring method.

Background technique

Currently, the measuring device of measurement screw pitch largely uses screw gauge and projector to measure.These measurements are set Standby measurement efficiency is low, and measurement accuracy is not high, is unable to satisfy some pairs of higher requirements of bolt pitch measurement ratio of precision.

Summary of the invention

The high and high spiral shell based on laser displacement sensor of measurement accuracy the object of the present invention is to provide a kind of measurement efficiency Bolt pitch measurement device and measurement method.

In order to achieve the above object, the technical scheme adopted by the invention is that: a kind of spiral shell based on laser displacement sensor Bolt pitch measurement device, including experimental bench, the laser displacement sensor being connected with host computer, for installing laser displacement sensor Fixing axle and multiple for placing the V-block of bolt to be measured, the measuring device is for surveying the screw pitch of bolt to be measured Amount, multiple V-blocks are along the setting of the length direction interval of experimental bench and bolt to be measured is placed on multiple V-blocks Top, fixing axle is arranged along the vertical direction and the bottom end of fixing axle is fixedly connected by fixed plate with experimental bench, the top of fixing axle End is provided with column support, and laser displacement sensor is connected by sensor mounting plate with column support.

Further, the V-groove for placing bolt to be measured is offered at the top of the V-block.

Further, the plane where the central axis with experimental bench of the fixing axle is vertical.

A kind of measurement method of the bolt pitch measurement device based on laser displacement sensor, comprising the following steps: first The profile information of bolt to be measured is acquired using laser displacement sensor to form set of data points；Then given threshold is by data point New set of data points is formed after satisfactory data point screening in set；Wave crest is extracted using wave crest extraction algorithm and to phase The distance between adjacent wave peak is calculated；Finally screw pitch is obtained according to the distance between adjacent peaks.

Further, it defines the data point set and is combined into { Q_i(x_i,y_i), wherein 0 < i < 800mm, given threshold u, If y_i> u, point Q_i(x_i,y_i) storage is into new set of data points, to form new set of data points { P_i(x_i,y_i)}；

In new set of data points { P_i(x_i,y_i) in, if there is data point meets y_i>y_i-1And y_i>y_i+1, then will meet the requirements Data point be extracted as wave crest Q₁(x_i,y_i), if new set of data points { P_i(x_i,y_i) between every two consecutive number strong point away from From for fixed value q, then the distance between adjacent peaks can be acquired are as follows:Finally according between adjacent peaks away from From you can get it screw pitch.

Further, new set of data points { P is being formed_i(x_i,y_i) after, it is further comprising the steps of: by new data point Gather { P_i(x_i,y_i) be built into data point curve and piecewise fitting is carried out to the data point curve.

Further, B-spline curves fitting algorithm piecewise fitting is used when carrying out piecewise fitting to data point curve.

Compared with prior art, the beneficial effects of the present invention are: the invention firstly uses laser displacement sensor acquisition to The profile information of bolt is surveyed to form set of data points；Then given threshold sieves data point satisfactory in set of data points New set of data points is formed after choosing；Wave crest is extracted using wave crest extraction algorithm and the distance between adjacent peaks are counted It calculates；Screw pitch finally is obtained according to the distance between adjacent peaks, and measurement method of the present invention is simple, high-efficient, moreover, the present invention exists New set of data points is built into data point curve and piecewise fitting is carried out to the data point curve, so that the present invention can be improved Measurement accuracy.

Detailed description of the invention

Fig. 1 is a kind of overall structure diagram of bolt pitch measurement device based on laser displacement sensor；

Marked in the figure: 1, fixing axle, 2, column support, 3, sensor mounting plate, 4, laser displacement sensor, 5, bolt to be measured, 6, V-block, 7, experimental bench, 8, fixed plate.

Specific embodiment

In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with attached in the present invention Figure, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is the present invention A part of the embodiment, instead of all the embodiments, based on the embodiments of the present invention, those of ordinary skill in the art are not having Every other embodiment obtained under the premise of creative work is made, shall fall within the protection scope of the present invention.

As shown in Figure 1, a kind of bolt pitch measurement device based on laser displacement sensor, including experimental bench 7, with it is upper The connected laser displacement sensor 4 of machine, the fixing axle 1 for installing laser displacement sensor 4 and multiple to be measured for placing The V-block 6 of bolt 5, the measuring device is for measuring the screw pitch of bolt 5 to be measured, and multiple V-blocks 6 are along experiment The length direction interval of platform 7 is arranged and bolt to be measured 5 is placed on the tops of multiple V-blocks 6, and fixing axle 1 is along vertical side Be fixedly connected to the bottom end of setting and fixing axle 1 by fixed plate 8 with experimental bench 7, herein, fixed plate 8 can be set it is multiple, Multiple fixed plates 8 are the rectangular aluminium sheet with tapped through hole, and multiple fixed plates 8 are fixed by screws on experimental bench 7；It is fixed The top of axis 1 is provided with column support 2, and laser displacement sensor 4 is connected by sensor mounting plate 3 with column support 2, laser The Laser emission of displacement sensor 4 rectifies the thread segment to bolt 5 to be measured, the collected profile information of laser displacement sensor 4 Master system (not drawn in the figure) is transmitted in the form of data point to carry out the processing of data and the calculating of screw pitch.

This programme is advanced optimized, the top of the V-block 6 offers the V-groove for placing bolt 5 to be measured.

This programme is advanced optimized, the central axis of the fixing axle 1 is vertical with the plane where experimental bench 7.

A kind of measurement method of the bolt pitch measurement device based on laser displacement sensor, comprising the following steps: first The profile information of bolt 5 to be measured is acquired using laser displacement sensor 4 to form set of data points；Then given threshold is by data New set of data points is formed after satisfactory data point screening in point set；Wave crest and right is extracted using wave crest extraction algorithm The distance between adjacent peaks are calculated；Finally screw pitch is obtained according to the distance between adjacent peaks.

This programme is advanced optimized, the data point set is defined and is combined into { Q_i(x_i,y_i), wherein 0 < i < 800mm, setting Threshold value is u, if y_i> u, point Q_i(x_i,y_i) storage is into new set of data points, to form new set of data points { P_i (x_i,y_i)}；

In new set of data points { P_i(x_i,y_i) in, if there is data point meets y_i>y_i-1And y_i>y_i+1, then will meet the requirements Data point be extracted as wave crest Q₁(x_i,y_i), if new set of data points { P_i(x_i,y_i) between every two consecutive number strong point away from From for fixed value q, then the distance between adjacent peaks can be acquired are as follows:Finally according between adjacent peaks away from From you can get it screw pitch.

This programme is advanced optimized, new set of data points { P is being formed_i(x_i,y_i) after, it is further comprising the steps of: will be new Set of data points { P_i(x_i,y_i) be built into data point curve and piecewise fitting is carried out to the data point curve.

This programme is advanced optimized, when carrying out piecewise fitting to data point curve using B-spline curves fitting algorithm point Section fitting.

The process for carrying out piecewise fitting to data point curve is specific as follows:

The parameter value of data point is calculated firstWith knot vector U, the linear minimum of unknown control vertex is then established and solved Two multiply problem.If giving m+1 Orderly data points Q₀,Q₁,···,Q_m(m >=n), approximating curve number k >=1, k B-spline Curve are as follows:

Meet endpoint constraint i.e. interpolation both ends data point Q₀=P (0), Q_m=p (1), remaining data points Q_i(i=1,2, M-1 it) is approached in least square meaning, i.e. objective function:

The general inaccurate excessively interior data point Q of approximating curve_i, andIt is not the distance q on curve_iClosest approach, if

By parameter valueAnd above formula brings preceding formula into, then has

Using the linear least square fitting technology of standard, objective function f to be made is minimum, it should be made about n-1 control vertex d_iThe derivative of (j=1,2, n-1) is equal to zero.Its first of derivative are as follows:

It is available

Then

One is defined with control vertex d₁,d₂,···,d_n-1For the system of linear equations of unknown quantity, l=1,2, n-1, Then obtain the equation group of the n-1 equation containing the n-1 unknown quantitys are as follows:

(N^TN) D=R

N is (m-1) × n-1 rank scalar matrix

N^TIt is the transposed matrix of N, R and D are the matrixes containing n-1 vector element

The above-mentioned least-squares algorithm approached for B-spline curves, it is known that data point set { P } can fit piecewise B-Spline song Line.

When there are small gap, directly with spacing of the quantity multiplied by point is put, there are large errors, in order to reduce error, Fitting cubic B-spline function can make up missing a little, improve the precision of measurement.

The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, as defined herein General Principle can be realized in other embodiments without departing from the spirit or scope of the present invention.Therefore, of the invention It is not intended to be limited to the embodiments shown herein, and is to fit to and the principles and novel features disclosed herein phase one The widest scope of cause.