Patent ID: 7128808

Claim:
A method of identifying a mapping of a paper machine actuator in a paper making process, the method comprising: a) performing a mapping test to obtain a mapping test result; b) forming a first non-linear shrinkage profile of the paper web, the non-linear shrinkage profile having an effect associated therewith; c) linearizing the mapping test result, the mapping test result having the effect of the first non-linear shrinkage profile eliminated therefrom; d) forming a first mapping model not including the effect of the non-linear shrinkage profile; e) comparing the linearized mapping test result with the first mapping model to produce a first linear mapping error; f) forming a second mapping model including the effect of the non-linear shrinkage profile; g) comparing the second mapping model with the mapping test result to produce a second linear mapping error; h) forming an actual total error of linear errors from a difference between the first linear mapping error and the second linear mapping error; i) determining an allowable total error of linear errors; and j) comparing the actual total error of linear errors with the allowable total error of linear errors, and in the event that a difference therebetween is not greater than a predetermined value, then concluding I) that the non-linear shrinkage profile is acceptable to be used in the second mapping model and II) that the first and second linear mapping errors indicate a linear error in the second mapping model, whereby one of the first and second linear mapping errors is then used to correct the linear error in the second mapping model, and in the event that the difference therebetween is larger than the predetermined value, then forming a second non-linear shrinkage profile and repeating method steps c) to j) for the second non-linear shrinkage profile in place of the first non-linear shrinkage profile.