en Description B Color line sensor FE 5002

6.2 Optimising and setting
specific parameters
Color line sensor FE 5002
In the case of clear guiding criteria no changes to the following
parameters are necessary. To display the sensor scan
and optimize parameters a CANMON program or command
station DO 2000 is required.
Default values are selected so that the majority of guiding criteria
may be detected. As guiding criteria are mostly subject to certain
fluctuations the individual tolerances are wide. Nevertheless in order
to identify the guiding criterion with great reliability the guiding
criterion must adhere to all tolerances.
The effect of changes in the relevant parameters may be checked
immediately in parameter "DSP reason of lost" and "per cent of valid"
Attention: a "per cent of valid" of 100 % may not be achieved by
widening the tolerances (increasing parameter values). A "per cent of
valid" of 70 % is a very good value! At 15 % guiding still works (e.g.
broken guiding criterion).
If tolerances are widened the sensor will no longer be able to distinguish
different guiding criteria, the sensor may then also jump to a
similar guiding criterion!
In the case of difficult criteria better results may be achieved with
narrower tolerances.
Optimization example (line width tolerance):
First of all the line width parameter value is reduced until the "percent
of valid" parameter value decreases.
If the parameter value is increased a little again the sensor should
permanently signal valid. Loss of a constant guiding criterion is
henceforth more or less excluded.
If each parameter in question is successively set in this way operation
will be with very narrow tolerances, precisely adjusted to the
guiding criterion.
The benefit is a clear identification of the guiding criterion without
possible limiting of the search range.
The following parameters are suitable for optimizing:
.3.3. / .4.0. width tolerance
.3.5. /.4.2. / .4.8. contrast tol
.3.7. /.4.4. / .5.0. color tolerance
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