LIBRARY ı6ıul 0) - Cranfield University

Figure 3.12 Offsets for weld start and end points 91
Figure 3.13 Points used to obtain the transformation matrix between Robot World and CAD 91
co-ordinates frames
Figure 3.14 Welding torch configuration for robot in zero position 92
Figure 3.15 Torch orientation sphere 92
Figure 3.16 Front view of the torch orientation sphere 92
Figure 3.17 Torch orientations for approach vector contained in planes with angles between 60 93
deg and 90 deg
Figure 3.18 Torch orientation for approach vector contained in plane rotated about the 94
sphere's X-axis by 120 deg
Figure 3.19 Torch orientation for approach vector contained in plane rotated about the 94
sphere's X-axis by 150 deg
Figure 3.20 Torch orientation for approach vector contained in plane rotated about the 95
sphere's X-axis by angles between 180 deg and 225 deg
Figure 3.21 Torch orientation for approach vector contained in plane rotated about the sphere's 96
X-axis by angles between -45 deg and 60 deg
Figure 3.22 Definition of "workpiece extension box" and "workpiece clearance box" 97
Figure 3.23 Method used to determine the weld approach and withdrawal points 97
Figure 3.24 Case when four approach points are necessary 98
Figure 3.25 Control system 98
Figure 4.1 Sketch of the moving table implemented in the control system 114
Figure 4.2 Process control shown schematically 114
Figure 5.1 Touch sensor schematic circuit 122
Figure 5.2 Implemented 1 degree-of-freedom moving table 123
Figure 5.3 Full system 123
Figure 5.4 Torque "versus" speed curves for stepper motor used (size 23,5V, IA, using 2A 124
unipolar drive)
Figure 5.5 BDH 550 wire feed speed calibration curve 124
Figure 5.6 Calibration curve for table displacement 125
Figure 5.7 Calibration curve for Robot Interface voltage input channel 125
Figure 5.8 Calibration curve for Robot Interface wire-feed-speed channel 125
Figure 6.1 Mean Voltage "versus" Set-up Voltage chart for the BDH 550 welding power 146
source
Figure 6.2 Comparison between predicted welding current and actual welding current 146
delivered by BDH320 and BDH550 welding power sources
Figure 6.3 Comparison between maximum welding currents in dip mode of metal transfer 147
delivered by BDH320 and BDH550 welding power sources
Figure 6.4 Measured "versus" Predicted leg length 147
Figure 6.5 Measured "versus" Predicted fusion penetration 148
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