CN103690145A - Computer optometry unit - Google Patents

Abstract

The invention relates to a computer optometry unit which is characterized by comprising a base assembly, a control assembly, a screen assembly, a head support assembly, a three-dimensional translation assembly and a monitoring assembly. The control assembly comprises an electrical control hardware portion and an electrical control algorithm software portion, the electrical control hardware portion drives a stepping motor by subdivision driving of an integrated chip through a high-performance microcontroller and a constant current chopping two-phase stepping motor, the microcontroller inputs pulse and level signals to control the running step number and the direction of the stepping motor, the electrical control software algorithm simulates acceleration and deceleration S-shaped curves by an S-shaped curve acceleration and deceleration control method, simulates a corresponding speed change step curve and calculates the frequency and the execution step number of each discrete point, a PWM (pulse width modulation) functional module inside the microcontroller is configured according to frequency parameters to output square-wave signals under corresponding frequency, the execution step number of the motor is accumulated in the output process, and the stepping motor reaches a specified position after all frequency pulses are outputted.

Description

A kind of rafractive

Technical field

The present invention relates to a kind of eyes measuring device, specifically a kind of rafractive.

Background technology

Current rafractive adopts objective measurement mode, and it produces dispersion image at the bottom of infrared image is projected to human eye on human eye retina, and the measurement image collecting by analyzing CCD calculates the diopter of eyes objectively.

When measuring, operator with the movement of the front, back, left, right, up, down of the light control instrument of have gentle hands, catches the pupil of measured's eyes, aims at after eyeball pupil, presses measurement key, and measurement result can be presented on screen immediately.

The accuracy of rafractive is subject to the impact of several factors, for example measured's head and eye coordinate bad, move about, eye fixation eye refractometer internal object is concentrated not, so that loosens adjusting not, must affect the accuracy of dioptroscopy result, even the number of degrees of rechecking differ greatly, especially child patient, the error of rafractive test is larger, even can not check out refractive diopter.

Therefore, existing rafractive requires high to operator, and he also must constantly pay close attention to measured's cooperation situation in skilled manipulation instrument, completes fast the system actings such as seizure, aligning, button, could obtain measurement result accurately.

Summary of the invention

The present invention is directed to above-mentioned defect, a kind of rafractive is provided, can automatically detect fast and accurately, simple to operate, each parts operate steadily, and use comfortable.

For this reason, the present invention takes following technical scheme, a kind of rafractive, comprise base assembly, control assembly, screen assembly are also being set on the platform of base assembly, the front end of base assembly is arranging head rest assembly, it is characterized in that at head rest assembly and control between assembly three-dimensional translating assembly is set, and by controlling assembly, completes the automatic of eyes or manual control detection;

Described three-dimensional translating assembly comprises Lift Part, on Lift Part, arrange and move forward and backward parts and to move left and right parts, described in move left and right parts top monitoring assembly is set; Described Lift Part comprises attitude reference device and actuating unit, makes to move forward and backward parts make vertical displacement movement by attitude reference device and actuating unit.

Described control assembly comprises electrical control hardware components and electrical control algorithm software part, electrical control hardware components is in conjunction with the segmentation of constant current chopper formula two-phase stepping motor, to drive the mode of integrated chip to realize the driving to motor with high-performance microcontroller, and microcontroller input pulse and level signal are carried out operation step number and the direction of control step motor; The algorithm of electrical control, it adopts S type curve Acceleration-deceleration Control Method to simulate acceleration and deceleration S type curve, by discrete logarithm, acceleration and deceleration curves is carried out to discretization again, make the final acceleration and deceleration curves of motor become stepped change shape, the desired value moving according to measuring device and the difference of current location are determined the maximum speed V of this motor running _maxwith acceleration time T, by algorithm simulation, go out corresponding velocity variations staircase curve, and calculate the frequency of various discrete point and carry out step number, then press the square-wave signal of the PWM functional module output respective frequencies of frequency parameter configuration microcontroller inside, and accumulative total motor is carried out step number in output procedure, after the execution podometer of current Frequency point is expired, jump to next Frequency point and carry out identical flow process, after the output that completes all Frequency point pulses, motor arrives assigned address.

The described parts that move forward and backward comprise and move forward and backward base plate and motor, described moving forward and backward on base plate arranging and moving forward and backward mandrel, front and back translation screw rod and move forward and backward seat, the two ends that move forward and backward the front linear axis bearing in seat are all provided with linear bearing, in rear linear axis bearing, be provided with a linear bearing, the linear bearing that is trapezoidal profile is enclosed within and moves forward and backward in mandrel, by the travel mechanism's band that comprises motor, front and back translation screw combinations, moves forward and backward parts action front and back parallel;

The described parts that move left and right comprise being arranged on and move forward and backward moving left and right mandrel and moving left and right seat on seat, moving left and right mandrel is fixed by mandrel pressing plate, the two ends that move left and right the front linear axis bearing in seat are also all provided with linear bearing, in rear linear axis bearing, be provided with a linear bearing, the linear bearing that is equally trapezoidal profile is enclosed within and moves left and right in mandrel, moves left and right parts make left and right parallel by the travel mechanism's drive that comprises motor, left and right translation screw combinations.

Described Lift Part comprises lifting main shaft and is fixed on the column on base plate, lifting main shaft is inserted in the linear bearing in column, lifting main shaft upper end arranges and moves forward and backward parts, pressing plate is fastened on the bottom of lifting main shaft, makes to move forward and backward parts make vertical displacement movement by attitude reference device, actuating unit;

Described attitude reference device comprises lifting location-plate, lifting location-plate is provided with two through holes, the first through hole is enclosed within the linear bearing in column fixing, the second through hole is by the fixing linear bearing of lifting positioning seat, lifting locating shaft is located in this linear bearing, and the upper end of lifting locating shaft is fixed on and moves forward and backward in base plate.

Described actuating unit comprises apparatus for controlling of lifting and push-rod electric machine, and the upper end of push-rod electric machine is connected with lifting main shaft, and the lower end of push-rod electric machine is connected with base plate, and apparatus for controlling of lifting is controlled the work of push-rod electric machine.

Described head rest assembly comprises head bracket, chin strap, guide pad, elevating lever, lifting limit control device, location bearing, lifting screw, motor, described guide pad is fixed in head bracket, elevating lever is inserted in the axis hole of guide pad, its top is connecting chin strap, its range of movement, by the drive disk assembly band action elevating movement that comprises lifting screw, location bearing 46, motor combination, is controlled by lifting limit control device in its underpart.

Described discrete logarithm is as follows:

1) time T that will speed up rising is separated into n section uniformly, and n is positive integer, and every first gear speed is running time

2) in accelerator, the speed of i shelves (i is positive integer) is v _i

$v_i=\left\{\begin{array}{cc}2V_{\max }{\left(\frac{i}{n}\right)}^2,& i<\frac{n}{2}\\ V_{\max }(\frac{4i}{n}-\frac{{2i}^2}{n^2}-1),& \frac{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}<i<n\end{array}\right.$

3) the input pulse frequency f of i shelves speed in accelerator _i

Use the motor that step angle is θ, its step number of moving required execution in a week is

If the segmentation number of stepper motor driver is S _v, the input pulse frequency of i shelves speed is

$f_i=\left\{\begin{array}{cc}\frac{720}{\mathrm{\&theta;}}{S}_v{V}_{\max }{\left(\frac{i}{n}\right)}^2,& 0<i<\frac{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}\\ \frac{360}{\mathrm{\&theta;}}{S}_v{V}_{\max }(\frac{4i}{n}-\frac{{2i}^2}{n^2}-1),& \frac{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}<i<n\end{array}\right.$

4) the execution step number N having accelerated _i

The i shelves speed time of implementation

the step number that i shelves speed is carried out is

$N_i=f_i{t}_i=\left\{\begin{array}{cc}\frac{720}{\mathrm{\&theta;}}{S}_v{V}_{\max }{\left(\frac{i}{n}\right)}^2\frac{T}{n},& 0<i<\frac{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}\\ \frac{360}{\mathrm{\&theta;}}{S}_v{V}_{\max }(\frac{4i}{n}-\frac{{2i}^2}{n^2}-1)\frac{T}{n},& \frac{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}<i<n\end{array}\right.$

Completing the total step number that acceleration need to carry out is

Deceleration is the inverse process accelerating, and its discrete logarithm step is consistent with above-mentioned steps.

The present invention has the following advantages: 1, adopt automatic metering system, under automatic mode, to defocused, do not touch the button and also can automatically measure fast, it brings glad tidings for unskilled user.

2, the full-automatic mode of mobile employing of the front, back, left, right, up, down of this instrument checkout gear, it not only can three-dimensional move simultaneously, and accurate positioning, quick, steady, measured can easily detected under state, and after measuring images of left and right eyes diopter, the interpupillary distance that automatically completes two is measured.

3, user measured's the situation of constantly maintaining order at a public gathering, makes measurement result accurately and reliably, to detecting by manual measurement pattern as special measured such as ocular media opacities.

4, the three-dimensional translating assembly of this instrument, has solved the ubiquitous heavy and unstable problem of existing loom base plate Move Mode, makes checkout gear no matter under mode state manually or automatically, guarantees mobile freely steady.

Accompanying drawing explanation

Fig. 1 is structural representation of the present invention

Fig. 2 is the structural representation of head rest of the present invention

Fig. 3 is the side view of three-dimensional translating assembly of the present invention

Fig. 4 is the partial sectional view of three-dimensional translating assembly of the present invention.

Fig. 5 is the main block diagram of electrical control hardware of the present invention

Fig. 6 is the speed change curves figure of S type curve Acceleration-deceleration Control Method of the present invention

Fig. 7 is the acceleration change curve chart of S type curve Acceleration-deceleration Control Method of the present invention

Fig. 8 is the speed change curves after discretization in discrete logarithm of the present invention

In figure 1: screen assembly, 2. control assembly, 3. detect assembly, 4. head rest assembly, 5. base assembly, 6. three-dimensional translating assembly, 41. head brackets, 42. chin straps, 43. guide pads, 44. elevating levers, 45. lifting limit control devices, 46. location bearings, 47. lifting screws, 48. motors, 61. move forward and backward base plate, 62. move forward and backward seat, 63. motors, 64. move left and right mandrel, 65. rear linear axis bearings, 66. move forward and backward mandrel, 67. front linear axis bearings, 68. mandrel pressing plates, 69. move left and right seat, 70. front and back translation screw rods, 71. lifting location-plates, 72. lifting main shafts, 73. lifting positioning seats, 74. lifting locating shafts, 75. apparatus for controlling of lifting, 76. push-rod electric machines, 77. columns, 78. base plates, 79. left and right translation screw rods.

The specific embodiment

Below in conjunction with specific embodiment, further set forth the present invention.

A kind of rafractive as shown in Figure 1, comprise base assembly 5, control assembly 2, screen assembly 1 are also being set on the platform of base assembly 5, the front end of base assembly 5 is arranging head rest assembly 4, between head rest assembly 4 and control assembly 2, three-dimensional translating assembly 6 is set, by controlling assembly 2, completes the automatic of eyes or manual control detection;

As shown in Figures 2 and 3, three-dimensional translating assembly 6 comprises Lift Part, on Lift Part, arranges and moves forward and backward parts and move left and right parts, and the top that moves left and right parts arranges monitoring assembly; Lift Part comprises attitude reference device and actuating unit, makes to move forward and backward parts make vertical displacement movement by attitude reference device and actuating unit.

Moving forward and backward parts comprises and moves forward and backward base plate 61 and motor 63, move forward and backward on base plate 61 and arranging and moving forward and backward mandrel 66, front and back translation screw rod 70 and move forward and backward seat 62, the two ends that move forward and backward the front linear axis bearing 67 in seat 62 are all provided with linear bearing, in rear linear axis bearing 65, be provided with a linear bearing, the linear bearing that is trapezoidal profile is enclosed within and moves forward and backward in mandrel 66, by the travel mechanism's band that comprises motor 63,70 combinations of front and back translation screw rod, moves forward and backward parts action front and back parallel;

Moving left and right parts comprises being arranged on and moves forward and backward seat moving left and right mandrel 64 and moving left and right seat 69 on 62, move left and right mandrel 64 fixing by mandrel pressing plate 68, the two ends that move left and right the front linear axis bearing in seat 69 are also all provided with linear bearing, in rear linear axis bearing, be provided with a linear bearing, the linear bearing that is equally trapezoidal profile is enclosed within and moves left and right in mandrel 64, moves left and right parts make left and right parallel by the travel mechanism's drive that comprises motor 63,79 combinations of left and right translation screw rod.

Lift Part comprises lifting main shaft 72 and is fixed on the column 77 on base plate 78, lifting main shaft 72 is inserted in the linear bearing in column 77, lifting main shaft 72 upper ends arrange and move forward and backward parts, pressing plate is fastened on the bottom of lifting main shaft 72, makes to move forward and backward parts make vertical displacement movement by attitude reference device, actuating unit;

Attitude reference device comprises lifting location-plate, lifting location-plate 71 is provided with two through holes, the first through hole is enclosed within the linear bearing in column 77 fixing, the second through hole is by the fixing linear bearing of lifting positioning seat 73, lifting locating shaft 74 is located in this linear bearing, and the upper end of lifting locating shaft 74 is fixed on and moves forward and backward in base plate.

Actuating unit comprises apparatus for controlling of lifting 75 and push-rod electric machine 76, and the upper end of push-rod electric machine 76 is connected with lifting main shaft 72, and the lower end of push-rod electric machine 76 is connected with base plate 78, and apparatus for controlling of lifting 75 is controlled the work of push-rod electric machine.

As shown in Figure 4, head rest assembly 4 comprises head bracket 41, chin strap 42, guide pad 43, elevating lever 44, lifting limit control device 45, location bearing 46, lifting screw 47, motor 48, described guide pad 43 is fixed in head bracket 41, elevating lever 44 is inserted in the axis hole of guide pad 43, its top is connecting chin strap 42, its range of movement, by the drive disk assembly band action elevating movement that comprises lifting screw 47, location bearing 46, motor 48 combinations, is controlled by lifting limit control device 45 in its underpart.

Motor 63 and push-rod electric machine 76 are a kind of permanent magnet induction motors.Permanent magnet induction formula motor has the features such as step angle is little, output torque is large, dynamic property is good, effective actuator of moving as measuring device three-dimensional in the design.Wherein motor 63 is realized the movement of the front, rear, left and right of measuring device, and push-rod electric machine 76 is realized moving up and down of measuring device.According to the difference of all directions mobile motor load, select respectively the motor of different torques (load capacity).(mark moves left and right as X-direction, move forward and backward as Y direction, move up and down as Z-direction) wherein, so the basic identical this patent of X-axis and Y-axis load is used 57BYG series motor, and Z axis need to drive the movement of whole detection assembly, so this patent is used 86BYG series high-torque stepper motor.

As shown in Figure 5, control assembly of the present invention comprises electrical control hardware components and electrical control algorithm software part, electrical control hardware components is in conjunction with the segmentation of constant current chopper formula two-phase stepping motor, to drive the mode of integrated chip to realize the driving to motor with high-performance microcontroller, and microcontroller input pulse and level signal are carried out operation step number and the direction of control step motor; The algorithm of electrical control, it adopts S type curve Acceleration-deceleration Control Method to simulate acceleration and deceleration S type curve, by discrete logarithm, acceleration and deceleration curves is carried out to discretization again, make the final acceleration and deceleration curves of motor become stepped change shape, the desired value moving according to measuring device and the difference of current location are determined the maximum speed V of this motor running _maxwith acceleration time T, by algorithm simulation, go out corresponding velocity variations staircase curve, and calculate the frequency of various discrete point and carry out step number, then press the square-wave signal of the PWM functional module output respective frequencies of frequency parameter configuration microcontroller inside, and accumulative total motor is carried out step number in output procedure, after the execution podometer of current Frequency point is expired, jump to next Frequency point and carry out identical flow process, after the output that completes all Frequency point pulses, motor arrives assigned address.

For overcoming start and stop in motor running, impact large, in running, vibrations are large, noise is large, the shortcomings such as poor stability during frequent commutation, on the software control algorithm of this patent, adopt S type curve Acceleration-deceleration Control Method conventional in numerically-controlled machine tool system with level and smooth motor acceleration and deceleration process.

(1) acceleration and deceleration curves simulation

Adopt this control method to make the S-type curve shape of motor speed change (as shown in Figure 6).Motor by S type rate curve change the general experience of operation accelerate, subtract accelerations, at the uniform velocity, acceleration and deceleration, five processes of deceleration.And the acceleration value in its each velocity variations process is constant.

If the acceleration value of Ta, Tb, Tc, Td and Te time period is respectively A1, A2, A3, A4 and A5 in Fig. 1

And | A1|=|A2|=|A4|=|A5| ... 1.

If acceleration is a adding the accessible peak acceleration of accelerator _max, minimum acceleration is a ₀=0, acceleration temporal evolution curve as shown in Figure 7

Can obtain a _t1=a _t4=-a _max, a _t2=a _t2=a _t5=a ₀=0

And $A_1=\frac{a_{T1}}{T1}=\frac{a_{\max }}{\mathrm{Ta}},A_2=\frac{a_{T2}-a_{T1}}{T2-T1}=\frac{a_{\max }}{\mathrm{Tb}},$

$A_4=\frac{a_{T4}-a_{T3}}{T4-T3}=\frac{a_{\max }}{\mathrm{Td}},A_5=\frac{a_{T5}-a_{T4}}{T5-\mathrm{<figure-callout\; id="4"\; label="T"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">T</figure-callout>}4}=\frac{a_{\max }}{\mathrm{Te}}$ ……?……②

According to formula 1., 2. obtain Ta=Tb=Td=Te=T ₁,

And T ₂=Ta+Tb=2T ₁, T ₃=T ₂+ Tc=2T ₁+ Tc,

T ₄＝T ₃+Td＝3T ₁+Tc，T ₅＝T ₄+Te＝4T ₁+Tc…………③

Therefore can obtain a-t piecewise function

$a\left(t\right)=\left\{\begin{array}{cc}{A}_{1}t,& t\&Element;[0,T_1]\\ 2A_1{T}_1-A_{1}t,& t\&Element;(T_1,T_2]\\ 0,& t\&Element;({\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">T</figure-callout>}}_2,T_3]\\ 2A_1{T}_1-A_1(t-T_c),& t\&Element;(T_3,T_4]\\ A_1(t-T_c)-4A_1{T}_1,& t\&Element;({\mathrm{<figure-callout\; id="4"\; label="T"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">T</figure-callout>}}_4,T_5]\end{array}\right.$ ……?……④

According to becoming, accelerate space rate formula ?

$v\left(t\right)=\left\{\begin{array}{cc}{\mathrm{<figure-callout\; id="0"\; label="V"\; filenames="2013107247871100003DEST\_PATH\_IMAGE001.png,2013107247871100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">V</figure-callout>}}_0+{\&Integral;}_0^{t}a\left(t\right)\mathrm{dt},& t\&Element;[0,T_1]\\ {\mathrm{<figure-callout\; id="0"\; label="V"\; filenames="2013107247871100003DEST\_PATH\_IMAGE001.png,2013107247871100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">V</figure-callout>}}_0+{\&Integral;}_0^{t}a\left(t\right)\mathrm{dt}-{\&Integral;}_0^{T1}a\left(t\right)\mathrm{dt},& t\&Element;(T_1,T_2]\\ {\mathrm{<figure-callout\; id="0"\; label="V"\; filenames="2013107247871100003DEST\_PATH\_IMAGE001.png,2013107247871100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">V</figure-callout>}}_0+{\&Integral;}_0^{T2}a\left(t\right)\mathrm{dt}-{\&Integral;}_0^{T1}a\left(t\right)\mathrm{dt},& t\&Element;({\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">T</figure-callout>}}_2,T_3]\\ {\mathrm{<figure-callout\; id="0"\; label="V"\; filenames="2013107247871100003DEST\_PATH\_IMAGE001.png,2013107247871100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">V</figure-callout>}}_0+{\&Integral;}_0^{t}a\left(t\right)\mathrm{dt}-{\&Integral;}_0^{T3}a\left(t\right)\mathrm{dt},& t\&Element;(T_3,T_4]\\ {\mathrm{<figure-callout\; id="0"\; label="V"\; filenames="2013107247871100003DEST\_PATH\_IMAGE001.png,2013107247871100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">V</figure-callout>}}_0+{\&Integral;}_0^{t}a\left(t\right)\mathrm{dt}-{\&Integral;}_0^{T4}a\left(t\right)\mathrm{dt},& t\&Element;({\mathrm{<figure-callout\; id="4"\; label="T"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">T</figure-callout>}}_4,T_5]\end{array}\right.$ ……?……

To 3. 4. in substitution 5., obtain

$v\left(t\right)=\left\{\begin{array}{cc}{\mathrm{<figure-callout\; id="0"\; label="V"\; filenames="2013107247871100003DEST\_PATH\_IMAGE001.png,2013107247871100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">V</figure-callout>}}_0+\frac{1}{2}{A}_1{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">t</figure-callout>}}^2,& t\&Element;[0,T1]\\ {\mathrm{<figure-callout\; id="0"\; label="V"\; filenames="2013107247871100003DEST\_PATH\_IMAGE001.png,2013107247871100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">V</figure-callout>}}_0+2A_1{T}_{1}t-A_1{T}_1^2-\frac{1}{2}{A}_1{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">t</figure-callout>}}^2,& t\&Element;(T1,T2]\\ {\mathrm{<figure-callout\; id="0"\; label="V"\; filenames="2013107247871100003DEST\_PATH\_IMAGE001.png,2013107247871100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">V</figure-callout>}}_0+A_1{T}_1^2,& t\&Element;(\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">T</figure-callout>}2,T3]\\ {\mathrm{<figure-callout\; id="0"\; label="V"\; filenames="2013107247871100003DEST\_PATH\_IMAGE001.png,2013107247871100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">V</figure-callout>}}_0+A_1{T}_1^2-\frac{1}{2}{A}_1{(2T_1+T_c-t)}^2,& t\&Element;(T3,T4]\\ {\mathrm{<figure-callout\; id="0"\; label="V"\; filenames="2013107247871100003DEST\_PATH\_IMAGE001.png,2013107247871100003DEST\_PATH\_IMAGE002.png"\; state="\{\{state\}\}">V</figure-callout>}}_0+\frac{1}{2}{A}_1{(4T_1+T_c-t)}^2,& t\&Element;(\mathrm{<figure-callout\; id="4"\; label="T"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">T</figure-callout>}4,T5]\end{array}\right.$ ……?……⑥

If V ₀=0, and maximum speed and acceleration time be respectively V _maxand T

Can 6. be solved by formula

and can simulate acceleration and deceleration curves

(2) acceleration and deceleration curves discretization

Actual motor is carried out when digital control carrying out discretization to acceleration and deceleration curves, make the final acceleration and deceleration curves of motor become stepped change shape, as shown in Figure 8.

1) time T that will speed up rising is separated into n section (n is positive integer) uniformly

Every first gear speed is running time

2) in accelerator, the speed of i shelves is

$V_i=\left\{\begin{array}{cc}{2V}_{\max }{\left(\frac{i}{n}\right)}^2,& i<\frac{n}{2}\\ V_{\max }(\frac{4i}{n}-\frac{{2i}^2}{n^2}-1),& \frac{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}<i<n\end{array}\right.$

3) the input pulse frequency of i shelves speed in accelerator

For example, the motor step angle that patent is used is 1.8 °

Motor moves the step number of required execution in a week and is

If the segmentation number of stepper motor driver is S _v, the input pulse frequency of i shelves speed is

$f_i=\left\{\begin{array}{cc}400S_v{V_{\max \left(\frac{i}{n}\right)}}^2,& 0<i<\frac{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}\\ 200S_v{V}_{\max (\frac{4i}{n}-\frac{{2i}^2}{n^2}-1),}& \frac{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}<i<n\end{array}\right.$

4) the execution step number of having accelerated

The step number that i shelves speed is carried out is

$N_i=f_{i}t=\left\{\begin{array}{cc}400S_v{V}_{\max }{\left(\frac{i}{n}\right)}^2\frac{T}{n},& 0<i<\frac{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}\\ 200S_v{V}_{\max }(\frac{4i}{n}-\frac{{2i}^2}{n^2}-1)\frac{T}{n},& \frac{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000445868550000011.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}<i<n\end{array}\right.$

Completing the total step number that acceleration need to carry out is

Deceleration is the inverse process accelerating, and its discrete step is consistent with above-mentioned steps.

First the maximum speed V that the desired value of moving according to motor and current difference are determined this running _maxwith acceleration time T, by algorithm simulation, go out corresponding velocity variations staircase curve, and calculate the frequency of various discrete point and carry out step number.Then press the square-wave signal of the PWM functional module output respective frequencies of frequency parameter configuration microcontroller inside, and accumulative total motor is carried out step number in output procedure.After the execution podometer of current Frequency point is full, jump to next Frequency point and carry out identical flow process (signal of configuration PWM functional module output corresponding frequencies also judge that motor carry out step number), after the output that completes all Frequency point pulses, motor arrives assigned address.

The design of head rest assembly makes pupil position only understand variation in certain limit, so two kinds of modes position below can adopting in the movement of checkout gear: a kind of is that the motor of controlling X-axis, Y-axis, Z axis moves, and the second positions X-axis, Y-axis, Z axis according to precedence respectively successively simultaneously.For making instrument can keep the operation of long-term steady low shake, the design adopts the second way, the three-dimensional coordinate position information of the pupil focus that driver calculates according to measuring device successively mobile each shaft step motor makes measuring device finally arrive measuring position accurately, because pupil (determinand focus) changes limited space, make 3 d space coordinate excursion less, so that the arrival pupil position that measuring device can be exceedingly fast measure.

Should be understood that these embodiment are only not used in and limit the scope of the invention for the present invention is described.In addition should be understood that those skilled in the art can make various changes or modifications the present invention after having read the content of the present invention's instruction, these equivalent form of values fall within the application's appended claims limited range equally.

Claims (8)

1. a rafractive, comprise base assembly (5), upper control assembly (2), the screen assembly (1) arranging of base assembly (5), the head rest assembly (4) that base assembly (5) front end arranges, it is characterized in that being positioned on head rest assembly (4) base assembly (5) below three-dimensional translating assembly (6) is being set, detection assembly (3) is being set on three-dimensional translating assembly (6), by controlling assembly (2), is completing the automatic of eyes or manual control detection;

Described three-dimensional translating assembly (6) comprises Lift Part, arranges and move forward and backward parts and move left and right parts on Lift Part; Described Lift Part comprises attitude reference device and actuating unit, makes to move forward and backward parts make vertical displacement movement by attitude reference device and actuating unit;

Described control assembly (2) comprises electrical control hardware components and electrical control algorithm software part, electrical control hardware components is in conjunction with the segmentation of constant current chopper formula two-phase stepping motor, to drive the mode of integrated chip to realize the driving to motor with high-performance microcontroller, and microcontroller input pulse and level signal are carried out operation step number and the direction of control step motor; The algorithm of electrical control, it adopts S type curve Acceleration-deceleration Control Method to simulate acceleration and deceleration S type curve, by discrete logarithm, acceleration and deceleration curves is carried out to discretization again, make the final acceleration and deceleration curves of motor become stepped change shape, the desired value moving according to measuring device and the difference of current location are determined the maximum speed V of this motor running _maxwith acceleration time T, by algorithm simulation, go out corresponding velocity variations staircase curve, and calculate the frequency of various discrete point and carry out step number, then press the square-wave signal of the PWM functional module output respective frequencies of frequency parameter configuration microcontroller inside, and accumulative total motor is carried out step number in output procedure, after the execution podometer of current Frequency point is expired, jump to next Frequency point and carry out identical flow process, after the output that completes all Frequency point pulses, motor arrives assigned address.

2. rafractive according to claim 1, it is characterized in that the described parts that move forward and backward comprise and move forward and backward base plate (61) and motor (63), described moving forward and backward on base plate (61) arranging and moving forward and backward mandrel (66), before and after a translation screw rod (70) and move forward and backward (62), the two ends that move forward and backward the front linear axis bearing (67) in seat (62) are all provided with linear bearing, in rear linear axis bearing (65), be provided with a linear bearing, the linear bearing that is trapezoidal profile is enclosed within and moves forward and backward in mandrel (66), by comprising motor (63), travel mechanism's band of front and back translation screw rods (70) combination moves forward and backward parts action front and back parallel.

3. rafractive according to claim 2, it is characterized in that the described parts that move left and right comprise being arranged on and move forward and backward moving left and right mandrel (64) and moving left and right (69) on seat (62), move left and right mandrel (64) fixing by mandrel pressing plate (68), the two ends that move left and right the front linear axis bearing in seat (69) are also all provided with linear bearing, in rear linear axis bearing (65), be provided with a linear bearing, the linear bearing that is equally trapezoidal profile is enclosed within and moves left and right in mandrel (64), by comprising motor (63), travel mechanism's drive of left and right translation screw rod (79) combination moves left and right parts and makes left and right parallel.

4. rafractive according to claim 3, it is characterized in that described Lift Part comprises lifting main shaft (72) and is fixed on the column (77) on base plate (78), lifting main shaft (72) is inserted in the linear bearing in column (77), lifting main shaft (72) upper end arranges and moves forward and backward parts, pressing plate is fastened on the bottom of lifting main shaft (72), makes to move forward and backward parts make vertical displacement movement by attitude reference device, actuating unit.

5. rafractive according to claim 4, it is characterized in that described attitude reference device comprises lifting location-plate, lifting location-plate (71) is provided with two through holes, the first through hole is enclosed within the linear bearing in column (77) fixing, the second through hole is by the fixing linear bearing of lifting positioning seat (73), lifting locating shaft (74) is located in this linear bearing, and the upper end of lifting locating shaft (74) is fixed on and moves forward and backward in base plate.

6. rafractive according to claim 5, it is characterized in that described actuating unit comprises apparatus for controlling of lifting (75) and push-rod electric machine (76), the upper end of push-rod electric machine (76) is connected with lifting main shaft (72), the lower end of push-rod electric machine (76) is connected with base plate (78), and apparatus for controlling of lifting (75) is controlled the work of push-rod electric machine.

7. rafractive according to claim 6, it is characterized in that described head rest assembly (4) comprises head bracket (41), chin strap (42), guide pad (43), elevating lever (44), lifting limit control device (45), location bearing (46), lifting screw (47), motor (48), described guide pad (43) is fixed in head bracket (41), elevating lever (44) is inserted in the axis hole of guide pad (43), its top is connecting chin strap (42), its underpart is by comprising lifting screw (47), location bearing (46), the drive disk assembly band action elevating movement of motor (48) combination, by lifting limit control device (45), control its range of movement.

8. according to the rafractive described in claim 1 or 7, it is characterized in that described discrete logarithm is as follows:

1) time T that will speed up rising is separated into n section uniformly, and n is positive integer, and every first gear speed is running time

2) in accelerator, the speed of i shelves (i is positive integer) is v _i

3) the input pulse frequency f of i shelves speed in accelerator _i

Use the motor that step angle is θ, its step number of moving required execution in a week is

If the segmentation number of stepper motor driver is S _v, the input pulse frequency of i shelves speed is

4) the execution step number N having accelerated _i

The i shelves speed time of implementation

the step number that i shelves speed is carried out is

Completing the total step number that acceleration need to carry out is

Deceleration is the inverse process accelerating, and its discrete logarithm step is consistent with above-mentioned steps.

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