CN102621482B - Testing pen needle lower point correcting method - Google Patents

Abstract

The invention discloses a method for correcting and accurately positioning a needle lower point of a testing pen by using a camera. After the needle lower point is corrected, the arrival of the testing pen at a detected target point can be judged only by observing the alignment of a cross cursor and the detected target point on a computer screen without dropping down the testing pen to enable the detecting needle to contact a circuit board; therefore, the testing pen can accurately fall to the detected target point.

Description

A kind of point calibration method under test probe pen pin

Technical field

The present invention relates to field of automatic testing, relate in particular under a kind of test probe pen pin and put auto-correction method.

Background technology

At present, the use of electronic product is more and more, and electronic product is while breaking down, often needs circuit board wherein to carry out fault diagnosis.The Chinese patent application file that is " CN 101806857A " as publication number discloses a kind of online fault diagnostic apparatus for circuit board, include for carrying out online signal and process with the host computer of fault diagnosis and be used to circuit-under-test plate that desired signal is provided and upload the slave computer of detecting information, host computer is connected and communicates by letter with slave computer employing universal serial bus.Host computer adopts portable notebook computer, in-built Failure Detection Expert System Software, slave computer function comprises generation control and test data collection and the analysis ratiocination etc. of pumping signal, carries out the fault diagnosis of circuit board or components and parts in conjunction with fault diagnosis expert system.After circuit-under-test plate is received on the interfacing equipment of slave computer, apply various pumping signals by PC control slave computer to circuit-under-test plate, then carry out the collection of response signal, according to collection result, start fault diagnosis expert system, localization of fault, to replaceable components and parts, is realized to the on-line fault diagnosis to electronic devices and components.As shown in the above, current Fault Diagnosis of Circuit Board is all, by signal-testing apparatus, signal exciting bank, test probe pen, circuit board is carried out to fault diagnosis, but all need artificial use test probe pen to survey impact point, thereby the leg signal of the components and parts on circuit board is carried out to data acquisition.The not only waste of manpower of method that this artificial use test probe pen is tested, and easily there is mistake, very inconvenient.And for the device pin spacing apart from only having a few tenths of a mm, artificial adjustment test probe pen position is pretty troublesome thing, be difficult to probe to drop on correct position, also can affect thus fault diagnosis result.

Summary of the invention

The object of this invention is to provide a kind of point calibration method under test probe pen pin of the test probe pen that is applicable to mechanical arm or robot, make to test probe pen and can fall accurately measured target point.

The present invention is a kind of point calibration method under test probe pen pin, comprises the following steps:

1., target disc is placed on circuit-under-test plate to certain a bit, wherein target disc is a circular picture;

2., making to test probe pen drops on target disc center and then lifts test probe pen;

3., central control unit control camera is taken pictures to target disc;

4., central control unit is according to taking to such an extent that photo finds the pixel of target disc central point and the corresponding camera photo-sensitive cell of target disc central point, point under pin on the screen that the pixel of the corresponding camera photo-sensitive cell of definition target disc central point is central control unit, on this pixel on the screen of central control unit, mark tracking cross, can complete the trimming process of putting under pin.

The present invention proofreaies and correct point under the pin of test probe pen, after point calibration under pin, later as long as watch tracking cross to aim at measured target point on computer screen, and needn't drop test probe pen make probe contact circuit plate, can judge that test probe pen reaches measured target point, accurately falls measured target point thereby can make to test probe pen.

Brief description of the drawings

Fig. 1 is a kind of mechanical arm proposing in the present invention and the structural representation of testing probe pen;

Fig. 2 is the position view of testing probe pen and circuit-under-test plate and camera in the present invention.

Embodiment

As shown in Figure 1 and Figure 2, in the present invention, drive test probe pen to move by mechanical arm, described mechanical arm (but being not limited only to this kind) is integrally formed to motion 1, Y-direction motion 2, Z-direction motion 3 by X.X is all fixed with the first servomotor 11, the second servomotor 12 and the 3rd servomotor 13 for driving motion motion to the end of motion 21, Y-direction motion 22, Z-direction motion 23, central control unit moves by servo-control system control the first servomotor 11, the second servomotor 12 and the 3rd servomotor 13.Camera 20 is arranged on Z-direction motion 23.Photography/videography head 4 is arranged on Z-direction motion 3, and camera 4 is connected by usb bus with central controller, and central controller is computing machine.When needs are taken pictures, central controller sends control signal takes pictures camera 4, and camera 4 is selected suitable pixel value according to accuracy requirement difference.The optical axis of camera 4 has tiltangleθ with test probe pen 5, and the object of tiltangleθ is to ensure that camera 4 can correctly photograph impact point and certain limit and not tested probe pen 5 is blocked around.When installation, should make the Y coordinate of camera 4 basic identical with the Y coordinate of test probe pen, camera 4 optical axises are substantially crossing with the measured target point M on circuit-under-test plate 6.Here " basic identical " and " substantially crossing " are because reach " identical " and " completely crossing " is very difficult by mechanical erection.

The present invention can become " identical " and " completely crossing " by " basic identical " and " substantially crossing " by point calibration under pin, reaches the data acquisition of correctly carrying out measured target point.Concrete grammar step is as described below,

1., target disc is placed on circuit-under-test plate to certain a bit, wherein target disc is a circular picture, 2., making to test probe pen 5 drops on target disc center and then lifts test probe pen, 3., central controller controls camera 4 is taken pictures to target disc, 4., central control unit is according to taking to such an extent that photo finds the pixel of target disc central point and the corresponding camera photo-sensitive cell of target disc central point, the pixel of the corresponding camera photo-sensitive cell of definition target disc central point is point under the pin on computer screen, and some mark tracking cross under pin on computer screen.After point calibration under pin, later as long as watch tracking cross to aim at measured target point, and needn't drop test probe pen make probe contact circuit plate on computer screen, can judge that test probe pen reaches measured target point.

As shown in Figure 1, mechanical arm drives test probe pen 4 at x, the motion of y direction, and tracking cross moves on screen with probe pen.In the time that tracking cross is fallen impact point, probe pen has reached impact point.Wherein the first servomotor 11 connects Z-direction motion 23 by rotating translation converting means, makes Z-direction motion 23 drive probe pen to move at directions X; The second servomotor 12 turns translation device by rotation and connects X to motion 21, and X is moved in Y-direction to motion 21; The 3rd servomotor 13 turns translation device by rotation and connects card extender 5, probe pen support 3 is arranged on card extender 5, described test probe pen 4 is fixing by probe pen support 3, and the probe of probe pen exposes in the bottom of probe pen support 3, thereby makes card extender 5 drive test probe pen 4 to move in Z direction.Therefore mechanical arm has ensured that test probe pen 4 can move upward in directions X, Y-direction, Z side, and the signal output part of test probe pen 4 is connected with signal transmssion line 9.Wherein the rotation translation converting means described in the present embodiment is the device that the rotation of servomotor is converted to straight line translation, adopts ball-screw to complete.Describe as example in Y-direction motion taking X to motion 21: the second servomotor 12 rotates and drives the ball-screw of Y-direction motion 22 inside to be rotated, thereby the nut on drive ball-screw carries out Y-direction motion, nut is fixedly connected with to motion 21 with X by card extender 10, thereby drives X also to carry out Y-direction motion to motion 21.Z-direction motion 23 is the same at the motion principle of Z direction at motion and the card extender 5 of directions X, does not repeat them here.

Claims (1)

1. a point calibration method under test probe pen pin, is characterized in that: comprise the following steps:

1., target disc is placed on circuit-under-test plate to certain a bit, wherein target disc is a circular picture;

2., making to test probe pen drops on target disc center and then lifts test probe pen;

3., central control unit control camera is taken pictures to target disc;

4., central control unit is according to taking to such an extent that photo finds the pixel of target disc central point and the corresponding camera photo-sensitive cell of target disc central point, point under pin on the screen that the pixel of the corresponding camera photo-sensitive cell of definition target disc central point is central control unit, on this pixel on the screen of central control unit, mark tracking cross, can complete the trimming process of putting under pin.