  In this work, we present a method to estimate the mass distribution of a
rigid object through robotic interactions and tactile feedback. This is a
challenging problem because of the complexity of physical dynamics modeling and
the action dependencies across the model parameters. We propose a sequential
estimation strategy combined with a set of robot action selection rules based
on the analytical formulation of a discrete-time dynamics model. To evaluate
the performance of our approach, we also manufactured re-configurable block
objects that allow us to modify the object mass distribution while having
access to the ground truth values. We compare our approach against multiple
baselines and show that our approach can estimate the mass distribution with
around 10% error, while the baselines have errors ranging from 18% to 68%.
