ical
>ur-
me
ces
on-
fol-
the
ven
els,
dif-
and
an
oft-
igh
ve-
are
r, it
ree
ree
nt
sor
gle
fast
So
] of
by
reo
for
fast adjustment. Since the LMT functionality
enables the operator to control this adjust-
ment by software means (using single
stage movements e.g. during relative
orientation or data capturing for aerial trian-
gulation), this feature is removed.
After upgrading, the setting of a systematic
deviation in height measurements, at the
original BC performed by the so called spe-
cial keys, may be set at the LMT user
interface.
The speed control lever of the BC for pro-
filing is removed because the LMT supports
a very flexible profiling speed control with
all encoder input devices. Particularly, the
speed control by handwheels makes a finer
adjustment of the stages speed possible.
Like the original BC real-time processor
system, LMT supports the measuring mark
position display.
The so called "PFKB5" function keyboard
for simplified user input at the BC's applica-
tion software user interface is supported
further on for those users who intend to
continue working with their familiar BC ap-
plication software.
The pair of two footpedals of the BC is ex-
tended to three to achieve LMT compatibili-
ty; the interpretation of the switches
depends on the application software that is
enabled by LMT to interpret 6 different sig-
nals: pressed and released for all three
switches.
Like the original BC real-time processor
System, LMT sends a message to the host
application carrying status information
about the BC Ortho/Pseudo lever. Pack-
ages running on the host application com-
puter can access this information very
easily. However, current versions of appli-
cation software have to be adapted if this
feature is required.
Like the original BC real-time processor
System, LMT checks and consideres the
status of the optical positive/negative
95
changeover switch, i.e. diapositives and
negatives may be restituted in the same
way as before. The different positioning of
the stages is handled by LMT itself, without
affecting the application software at all.
The following table gives an overview com-
parison about the features supported by the
original and the upgraded BC instrument.
feature original BC | upgraded BC
free hand controller * *
profiling speed control * +
coordinate display + *
joy stick for fast * *
movements
good photo illumination + *
measuring mark posi- + +
tion display
status information + +
ortho/pseudo
status information + +
positive/negative
zero index of ground + +
height
b, movement + o
potential for superim- - *
position upgrade
Fig.2 : overview comparison of original BC with
upgraded BC instruments;
+ = is supported;
= is supported and improved;
0 = is not supported but replaced
by different tools;
= is not supported
3.3 Computer Replacement
The real-time microprocessor system on
the original BC is replaced by an Intel
based PC that fits into the cabinet of the
BC. If the application host computer is a PC
as well, both computers fit into that cabinet.
The communication between both plat-
forms is serial.