User`s guide

of the window (is downstream of the window), it is flagged as an error condition and the
application program can specify what action is to be taken. (See the description of the
BELT.MODE system parameter in V+ Language Reference Guide.)
If the normal error testing options are selected, whenever the V+ system is planning a robot
motion to a belt-relative location and the destination is outside the belt window but
upstream, the system automatically delays motion planning until the destination is within
the window. However, if an application program attempts to perform a motion to a belt-
relative destination that is out of the window at planning time (or is predicted to be out by the
time the destination would be reached) and this destination is downstream, a window-
violation condition exists. Also, if during the execution of a belt-relative motion or while the
robot is tracking the belt, the destination moves outside the belt window for any reason, a
window violation occurs. Depending upon the details of the application program, the program
either prints an error message and halts execution or branches to a specified subroutine
when a window violation occurs.
In order to provide flexibility with regard to the operation of the window-testing mechanism,
several modifications to the normal algorithms can be selected by modifying the value of the
BELT.MODE system parameter.
To assist in teaching the belt window, the Adept conveyor belt calibration program contains
routines that lead the operator through definition of the required bounding transformations.
Conveyor Terms
Belt-Relative Motion Instructions
To define a robot motion relative to a conveyor belt, or to define a relative transformation
with respect to the instantaneous location of a moving frame of reference, a belt variable can
be used in place of a regular transformation in a compound transformation. For example, the
instruction
MOVES %belt:loc_1
Basic Programming Concepts
V+Language User's Guide, v17.0
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