Learning IMM Filter Parameters from Measurements using Gradient Descent
André Brandenburger, Folker Hoffmann, Alexander Charlish
TL;DR
The paper tackles automatic tuning of Interacting Multiple Model (IMM) filter parameters using only measurement data, removing the need for ground-truth. It introduces a differentiable framework that minimizes a measurement-likelihood loss ${\mathcal{L}}({\bm{\theta}})$ via gradient descent to update the IMM's mode transitions, process noises, and measurement parameters. Through simulated experiments with two motion modes, the learned IMM matches the performance of an IMM with true parameters and outperforms a single-mode Kalman filter, while providing interpretable parameter updates. This approach enables practical, measurement-driven adaptation of complex multi-mode trackers for real sensors and can extend to more sophisticated architectures.
Abstract
The performance of data fusion and tracking algorithms often depends on parameters that not only describe the sensor system, but can also be task-specific. While for the sensor system tuning these variables is time-consuming and mostly requires expert knowledge, intrinsic parameters of targets under track can even be completely unobservable until the system is deployed. With state-of-the-art sensor systems growing more and more complex, the number of parameters naturally increases, necessitating the automatic optimization of the model variables. In this paper, the parameters of an interacting multiple model (IMM) filter are optimized solely using measurements, thus without necessity for any ground-truth data. The resulting method is evaluated through an ablation study on simulated data, where the trained model manages to match the performance of a filter parametrized with ground-truth values.
