Recursive Distillation for Open-Set Distributed Robot Localization
Kenta Tsukahara, Kanji Tanaka
TL;DR
This work tackles open-world self-localization for distributed robots where annotated training data is unavailable. It introduces data-free recursive distillation (DFRD), which reconstructs a pseudo-training dataset $D=\{(x,y)\}$ from a teacher model using a trainable synthesizer $g$ and uses it to train a student without accessing original data. The approach relies on a minimal assumption that the teacher's self-localization model can be used as a communication channel for knowledge transfer and employs a ranking-function as a generic teacher model, with sampling controlled by oracle/random mixes and regularized by the reciprocal-rank feature. Experiments on the NCLT dataset demonstrate robust, privacy-preserving continual learning across 10 seasons with a 100-place grid, showing that the open-set KT pipeline remains effective as the teacher set grows.
Abstract
A typical assumption in state-of-the-art self-localization models is that an annotated training dataset is available for the target workspace. However, this is not necessarily true when a robot travels around the general open world. This work introduces a novel training scheme for open-world distributed robot systems. In our scheme, a robot (``student") can ask the other robots it meets at unfamiliar places (``teachers") for guidance. Specifically, a pseudo-training dataset is reconstructed from the teacher model and then used for continual learning of the student model under domain, class, and vocabulary incremental setup. Unlike typical knowledge transfer schemes, our scheme introduces only minimal assumptions on the teacher model, so that it can handle various types of open-set teachers, including those uncooperative, untrainable (e.g., image retrieval engines), or black-box teachers (i.e., data privacy). In this paper, we investigate a ranking function as an instance of such generic models, using a challenging data-free recursive distillation scenario, where a student once trained can recursively join the next-generation open teacher set.
