Coating damages, such as cracks and spallation, always occur under high temperature gradient and its resulting residual stress level. This is why it is important and necessary to monitor and control the coating temperature during atmospheric plasma spray process. In this paper, a novel measurement approach for substrate and coating temperatures is presented. It is based on IR pyrometery combined to specific robot scanning trajectories in order to avoid harsh environment of spray workshops. The temperature-time evolution was continually detected and recorded during preheating, spraying and cooling stages and the two specific factors, periodic average temperature and standard deviation were adopted to evaluate the temperature variation and the fluctuation of the thermal cycle relevant to one robot scanning cycle based on the statistical method. These two factors were successful in describing the temperature variation during experimental processing sets. Finally, on the basis of experimental results of the influence of Z typed robot spray trajectory parameters, including spray distance, spray velocity and scanning step on coating temperature characterized by the two factors, an intelligent adaptive control of sprayed coating temperature was developed to obtain constant temperature cycles by means of adjusting robot trajectories, cooling, among other considered operating parameters. Excellent control performance is observed.

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