Page 15 - Welding Robots Technology, System Issues, and Applications

List of Figures xvii

background pulse time respectively, and I p and I b denote the peak
current and background current respectively. ............................................... 89
3.12. Butt joint with out of joint weld path. The weld voltage variance
shows only a slight change as the weld errors occur. A sophisticated
monitoring feature will however provide a robust alarm detection, in
this case a sequential probability ratio test (SPRT) [1]................................. 95
3.13. Block diagram for a monitoring system. ...................................................... 97
3.14. Sample T-joint with a step disturbance as illustrated with a gap. The
decision function will set the alarm above the threshold level. The
values of the x-axis represents millimeters along the weld joint [1]........... 100
4.1. Overview of a welding control system. ...................................................... 107
4.2. V-groove and fillet weld geometrical parameters....................................... 108
4.3. Using the current signal to find the joint center position............................ 109
4.4. Explanation of the laser vision principle. ................................................... 110
4.5. Basic scheme of a robotic welding control system..................................... 112
4.6. Single cell robotic welding system............................................................. 113
4.7. Networked robotic welding system: multi-cell........................................... 114
4.8. Using a programmable sensor. ................................................................... 115
4.9. Software architecture used (depicting two approaches: using
software components and OPC – OLE for Process Control [31])............... 119
4.10. Functionality of the RPC server necessary to receive spontaneous
messages. .................................................................................................... 122
4.11. Experimental setup used for the TCP/IP sockets server example
(ABB IRB1400 robot + ABB IRC5 robot controller)................................. 125
4.12. TCP/IP socket server RAPID code [43, 44]. .............................................. 129
4.13. TCP/IP socket client................................................................................... 130
4.14. Code detail for the client software.............................................................. 130
4.15. Simple welding application used for demonstration................................... 131
4.16. Multitasking environment: a - diagram showing how tasks
communicate using shared memory space; b - aspect of the
RobotStudio [43] RAPID tasks view, on the PC side, showing the
running tasks............................................................................................... 132
4.17. Starting and stopping welding. ................................................................... 136
4.18. Simply welding example include in a manufacturing line.......................... 140
5.1. Robotic welding system.............................................................................. 150
5.2. Welding sequence implemented by the robot controller (all the
timings are programmable by the user)....................................................... 151
5.3. Robot working as a server. ......................................................................... 152
5.4. Example of welding trajectories using available layers (using
AUTOCAD 2004)....................................................................................... 153
5.5. Application to extract information from a DXF CAD file.......................... 154
5.6. Definition of the welding file obtained from the DXF CAD file................ 155
5.7. Shell of the WeldPanel tool........................................................................ 156
5.8. Shell of the WeldAdjust tool....................................................................... 157
5.9. Robot File Explorer.................................................................................... 158
5.10. Robot Control Panel and RPC server ......................................................... 159