SIPLACE S-23 HM.pdf - 第224页

6 Vision functions User M anual SIPLACE S -23 HM 6.5 Teach Fiducial Software Version SR.406.xx 02/00 US E dition 224 The uniq ueness v alue appe ars as the mea suremen t results. Th is may v ary between 0 (= un sat- isfa…

User Manual SIPLACE S-23 HM 6 Vision functions

Software Version SR.406.xx 02/00 US Edition 6.5 Teach Fiducial

223

Å Make sure that there are no other structures within the search area. Otherwise, fiducial identi-

fication could be made unnecessarily more difficult.

Å Repeat the tests with different search area sizes. It may also be appropriate to optimize the

uniqueness value.

When you select the Search area option 6

– the menu closes,

– the teaching process is launched,

– the video image is shown with fiducial and search area, and

– header and footer with commentary, measurement results, key assignments and command se-

quences are displayed.

Fig. 6.5 - 16 Teach fiducial menu, Teach search area video image

Å Use the arrow keys to change the camera position. You can specify the step width by entering

a number in the range 1 - 6.

Å Use the + and - keys to move the fiducial structure boundaries and teach them at the same

time. With the space bar you can toggle between horizontal and vertical directions. With the

Tab key you can toggle the field step width between 1 pixel and 10 pixels.

Å Press Return to launch the teaching process.

Fiducial No. = 8 Uniqueness = 70

Blank: hor./vert.

Tab : step width

Change search area

1..6 : x/y step

: y axis +

: y axis -

x/y step width = ...Direction = ...Field step = ...

Ret: teach

- : smaller

+ : larger

: x axis +

: x axis -

6 Vision functions User Manual SIPLACE S-23 HM

6.5 Teach Fiducial Software Version SR.406.xx 02/00 US Edition

224

The uniqueness value appears as the measurement results. This may vary between 0 (= unsat-

isfactory) and 100 (= very good) differentiation capability. 6

Practice shows that a uniqueness value of at least 60 must be achieved for fiducials and ink dots. 6

Å Repeat the teaching process a number of times with changed field sizes. In this way you can

optimize the uniqueness value.

Å Press Esc to quit this option.

NOTE 6

If you wish to use a fiducial despite the fact that it has a low uniqueness value, you should

ensure that the fiducial has a good quality value (see Section 6.5.6.2 on page 235).

If the quality is bad as well, it would be better to select another fiducial (see Criteria for Cre-

ating Fiducials in Section 6.2.5 on page 190). 6

User Manual SIPLACE S-23 HM 6 Vision functions

Software Version SR.406.xx 02/00 US Edition 6.5 Teach Fiducial

225

6.5.5 Contrast Sensitivity Menu

The Contrast sensitivity menu provides options for optimizing the contrast between the fiducial

and its surroundings. 6

NOTE 6

All of the options in this menu are only accessible if you have loaded a fiducial beforehand. If you

have done so, this will be indicated by the text on the button being black (rather than grayed out).

The fiducial number and fiducial name are displayed in the Fiducial display field.

If you have not loaded a fiducial you will only be able to select the Program transform 5 option. 6

Fig. 6.5 - 17 Contrast sensitivity menu, options

Each pixel of the video camera contains one unit of 8-bit gray-scale information. The significance

of the values is as follows: 6

0 = black and

255 = white