Active Sensing Test Cases in Industrial Processes

Abstract

The effect of optimizing the information state of an LQG-control problem was studied. The measurements of the processes concerned were limited but controllable and the performance of the process was tested with different choices of measurements. Two test cases were considered: froth flotation process and paper machine basis weight control. In the froth flotation process, a linear process model was identified and a mathematically optimal solution for the measurement optimization problem was derived and tested with the model. The effect of the choice of measurement scheduling was tested and the cost of operation was identified to be in the scope from lower limit of 0.48 with standard error of 3.63 ∗ 10ˉ⁴ to upper limit of 0.74 with standard error of 3.96 ∗ 10ˉ⁴ (N=10⁶) with different choices of measurements. In the case on paper machine basis weight control, a simulator was used and a scheduling algorithm for a moving scanner measurement was built to dampen the effects of temporal and spatial deviations being intermingled due to the motion of the scanner measurement. Temporal oscillations in the basis weight detected as spatial oscillations in the estimates were greatly reduced due to the scheduling.