Resistance Spot Welding (RSW) is processed by using aluminum alloy used in the automotive industry. The difficulty of RSW parameter setting leads to inconsistent quality between welds. The important RSW parameters are the welding current, electrode force, and welding time. An additional RSW parameter, that is, the electrical resistance of the aluminum alloy, which varies depending on the thickness of the material, is considered to be a necessary parameter. The parameters applied to the RSW process, with aluminum alloy, are sensitive to exact measurement. Parameter prediction by the use of an artificial neural network (ANN) as a tool in finding the parameter optimization was investigated. The ANN was designed and tested for predictive weld quality by using the input and output data in parameters and tensile shear strength of the aluminum alloy, respectively. The results of the tensile shear strength testing and the estimated parameter optimization are applied to the RSW process. The achieved results of the tensile shear strength output were mean squared error (MSE) and accuracy equal to 0.054 and 95%, respectively. This indicates that that the application of the ANN in welding machine control is highly successful in setting the welding parameters. 1. Introduction In automotive production, each automobile has approximately 7,000 to 12,000 spot welds. The welds are done using the Resistance Spot Welding (RSW) process which is done by a computer controlled robotic welder. The use of RSW on lightweight aluminum alloy is increasing [1, 2]. RSW is a rapid joining technique extensively used to join thin shell assemblies in automotive manufacturing operations. It is an important process to ensure strong structural car bodies using lightweight materials to save both energy and natural resources [3]. The aluminum alloy material is a low density material with significant mechanical properties which is expected to be extensively used in the future to partially replace steel which is currently the primary production material in automobiles [4]. The 6061-T6 aluminum alloy is of light weight and has significant mechanical properties which are of interest in this research. The weld quality of the RSW process has been a significant problem for the automotive industry. Manual calculation of welding parameters, operator experience, and technician expertise in adjusting the parameter settings have not been consistently accurate or correct. The calculations have previously been unable to be confirmed against optimal parameters [5]. The parameter settings of each welding
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