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Appendix C
This appendix shows the user interface of the off-line programming module
developed for AutoCAD r12 using the AutoLISP programming language. The
dialogue boxes were defined using the Dialogue Control Language' .
The user interface was designed to guide the user through all the steps
necessary to define a weld. To use the off-line programming module the user must
create the solid model of the component in its final welded form. When the model is
ready, the off-line programming module must be loaded. This is carried out by
activating the AutoCAD pull down menu, selecting "Welding" and choosing "Load
Welding Module... " (see Figure C. 1). Once the off-line programming module is
loaded a weld can be defined. If no weld has been previously defined, the program
will show the dialogue box shown in Figure C. 2, which is used to define the model
coefficients' file which corresponds to the welding cell set-up. If the user wants to see
and/or modify a file shown in the list, he has to select it and "press" the button "View
File... " (see Figure C. 2). If a new file is to be added to the list, the user must select
"Add new file... ". If no change is necessary, the user just has to select the suitable file
description in the list and "press" the "OK" button (see Figure C. 2).
After selecting the coefficients file, the welding procedure generator main
dialogue box will appear (see Figure C. 3). This dialogue box guides the user
interactively through all the steps necessary to fully define a weld. These steps start by
defining the identification number for the weld followed by the selection of the edge
that represents the joint. The start and end points of the weld are then defined by
choosing the start and end points of the edge, respectively, and the offsets by which
the weld start and end points will be displaced from the corresponding edge points
along the joint line (see Figure C. 4). After having the weld positioning aspects
defined, the weld geometrical requirements are input (see Figure C. 5 and Figure C. 6).
If it is known from previous production experience that a gap is expected to be
present, its estimated value can be input by selecting "Yes" in the Gap definition
window (see Figure C. 5). The last parameter requested is the stand-off, this is
defaulted to 15 mm but the user can change this to any value within the allowable
range (12 mm to 15 nun). Having defined all the necessary parameters, the welding
parameters generator lists a series of possible welding parameters, from which the
user has to select one set (see Figure C. 7). The selected set is stored together with
other data as extended entity data associated with the edge representing the joint line
(see Appendix A).
After defining all the welds of the component, the robot program and the file
containing the robot teach points can be generated. This is carried out by selecting the
"Welding" pull down menu, "Output" and "Teach Robot". If no program has been
generated before during the same off-line programming session, a dialogue box used
to define the transformation matrix between the CAD co-ordinates system and the
Robot world co-ordinates system is launched (see Figure C. 8). In this dialogue box,
other data such as maximum and normal robot speed for non-welding movements and
' For more details Please refer to the AutoCAD r12 Customisation Manual
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