CN202928567U - Inclination angle measuring device based on CCD (Charge Coupled Device) - Google Patents

Abstract

The utility model relates to an inclination angle measuring device based on a CCD (Charge Coupled Device). A light spot position on a screen is measured by using the CCD, and then, an inclination angle is measured by using an image processing algorithm. The inclination angle measuring device has the structure as follows: damping liquid is stored in a container (4) in a shell (9); a pendulum bob (2) is hung in the damping liquid (3); a laser tube (1) fixed on the pendulum bob (2) emits light with the wavelength of 650nm; the light is emitted to the screen (6) through a reflecting mirror (5); a light spot image is collected by the CCD (7); and a computer image processor (8) is used for calculating the light spot position and giving out the inclination angle. The device is lower in cost and suitable for high-precision measuring of inclination angles.

Description

Dip measuring device based on CCD

Technical field:

The utility model relates to a kind of dip measuring device, specifically a kind of dip measuring device based on CCD.

Background technology:

Dip measuring device is commonly used mechanical pendulum angle measurement, air-bubble level, optical interference angular instrument etc.These devices are mostly that the lower one direction of precision is measured.Adopt the electric slope angle instrument precision of MEMS acceleration transducer higher, but temperature influence is larger.Patent CN1439863A proposes to adopt the device at liquid surface floating thing reflected light measurement inclination angle, and this measurement device precision is higher, but because Multi reflection light limits its measurement of dip angle scope.

Summary of the invention:

The purpose of this utility model is to propose a kind of dip measuring device based on CCD.This device adopts CCD to measure the position of luminous point, and measuring accuracy is high, and measurement range is large, and can measure simultaneously the inclination angle of both direction.

The technical solution of the utility model:

Have damping fluid in container, pendulum is suspended in damping fluid, is fixed on the light that laser tube on pendulum sends the 650nm wavelength, incides on screen through catoptron, and CCD gathers the dot pattern picture, and computer image processor is calculated light spot position and also provided the inclination angle size.

Computer image processor can adopt DSP embedded, utilizes the grey scale centre of gravity algorithm to calculate spot center, then calculates the inclination angle size.

The beneficial effects of the utility model are: compared with the prior art, the utility model is a kind of dip measuring device based on CCD, adopts common computer image processor, algorithm is simple, and measuring accuracy is high, and measurement range is large, can provide simultaneously the inclination angle of both direction, cost is very limited.

Description of drawings:

Fig. 1 is structural representation of the present utility model.

Fig. 2 is measurement of dip angle principle schematic of the present utility model.

Mark in figure: 1 laser tube, 2 pendulums, 3 damping fluids, 4 containers, 5 catoptrons, 6 screens, 7CCD, 8 computer image processor, 9 housings.

Embodiment:

As shown in Figure 1, based on the dip measuring device of CCD.Comprise 1 laser tube, 2 pendulums, 3 damping fluids, 4 containers, 5 catoptrons, 6 screens, 7CCD, 8 computer image processor, 9 housings.

Described laser tube 1 is fixed on pendulum 2, and pendulum 2 is put into the damping fluid 3 of container 4.

Described computer image processor 8 can adopt the DSP embedded based on TMS320DM642, and measurement result is presented on little liquid crystal display, is convenient to the measurement mechanism instrumentation.

Laser tube 1 sends the light of 650nm wavelength, incides on screen 6 through catoptron 5, and CCD7 gathers the dot pattern picture, and computer image processor 8 is calculated light spot position and provides the inclination angle size.Measuring principle is as follows:

As shown in Figure 2, establishing the inclination angle is α, and luminous point is s at the screen top offset, and catoptron is d to the distance of screen, and the inclination angle computing formula is arranged:

$\mathrm{\α}=\arctan \frac{s}{d}$

Wherein displacement s is obtained by computer image processor.Adopt the grey scale centre of gravity formula:

$x_c=\frac{{\mathrm{\Σ}}_{i_0}^{i_f}{\mathrm{\Σ}}_{j_0}^{j_f}j(T-f_{\mathrm{ij}})}{{\mathrm{\Σ}}_{i_0}^{i_f}{\mathrm{\Σ}}_{j_0}^{j_f}(T-f_{\mathrm{ij}})}$

$y_c=\frac{{\mathrm{\Σ}}_{i_0}^{i_f}{\mathrm{\Σ}}_{j_0}^{j_f}i(T-f_{\mathrm{ij}})}{{\mathrm{\Σ}}_{i_0}^{i_f}{\mathrm{\Σ}}_{j_0}^{j_f}(T-f_{\mathrm{ij}})}$

In formula T be dot pattern as gray threshold, f is the gray-scale value of each pixel, x and y are luminous point gray scale centre coordinates.Before and after tilting, the difference of luminous point gray scale centre coordinate is the displacement of x and y two directions.

The grey scale centre of gravity arithmetic accuracy is 0.02 pixel, and in image processing system, every pixel is corresponding 0.1 millimeter, and when catoptron was 200 millimeters to the distance of screen, this device measurement of dip angle precision was 10 ^-5Radian or 0.0005 °, luminous point are when mobile size is 50 millimeters on screen, and the measurement of dip angle scope is 14 °.

Claims (1)

1. dip measuring device based on CCD, it is characterized in that: have damping fluid in container (4) in housing (9), pendulum (2) is suspended in damping fluid (3), be fixed on the light that laser tube (1) on pendulum (2) sends the 650nm wavelength, incide on screen (6) through catoptron (5), CCD(7) gather the dot pattern picture, computer image processor (8) is calculated light spot position and is provided the inclination angle size.

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