Exact temperature tracking for hyperthermia: a model-based approach

In this paper, the inverse dynamics method for generating feedforward inputs and reference trajectories to achieve exact tracking for general linear time-invariant MIMO systems is explicitly derived. The method is applied to the task of generating input powers to achieve exact temperature tracking at multiple locations within a tumor during hyperthermia treatments. A number of important issues are considered: 1) robustness of the control schemes to parameter variation; 2) effect of additive sensor and actuator noise; 3) effect of using reduced order model estimators; and 4) effect of fast desired trajectories on the accuracy of output tracking. The inverse dynamics method is shown to be significantly more accurate when fast trajectories are desired. The results of this simulation study show that model-based inverse dynamics control is promising for clinical application. In addition, the inverse dynamics method derived can also be applied to other general linear MIMO systems.