Coating process and quality control of coated objects

A method for optimizing a coating process comprising a plurality of coating parameters and being performed by a painting line, the painting line including at least one painting system configured to dispense a coating on objects, the painting system having at least one robot and a controller controlling operations of the painting system, the method comprising modelling the coating process by performing the steps of:

• dispensing using the at least one robot, by means of the coating process and during K work cycles, a coating on each of K pieces of objects to thereby obtain K pieces of coatings;
• recording, during each of the K work cycles, coating variable values (xi,j) of p coating parameters at M instances to thereby obtain recording results (xjk, Xk);
• measuring at least one coating property at m locations of each of the K pieces of coatings to thereby obtain measurement results (yjk, Yk);
• determining a digital twin of the coating process on the basis of the recording results (xjk, Xk) and the measurement results (yjk, Yk), wherein the digital twin represents an approximation f′ of an unknown function f from coating variables to coating properties, wherein the approximation is such that Yk=f′(Xk)≈f(Xk);
• the method further comprising:
• providing a first coating variable value of at least one first coating parameter, the at least one first coating parameter representing an arbitrary parameter which is not regulable;
• calculating, on the basis of the first coating variable value and the digital twin, a second coating variable value for at least one second coating parameter, the at least one second coating parameter being different from the at least one first coating parameter and being regulable;
• and
• automatically adjusting the controller the second coating variable value to modify the dispensing operation performed by the at least one painting system;
• wherein i is an index referring to one of the M instances, wherein j is an index referring to one of the coating parameters, and wherein k is an index referring to one of the work cycles;
• and
• wherein K>100, M>1000, and m>10.