A Distributed Gaussian Process Model for Multi-Robot Mapping
Seth Nabarro, Mark van der Wilk, Andrew J Davison
AI summary
Problem
Centralized computation is infeasible for large-scale multi-robot mapping in dynamic or poorly connected environments, while existing distributed methods either suffer from accuracy limitations due to rigid connectivity constraints or lack scalability and local consistency.
Approach
The authors introduce DistGP, a sparse Gaussian process model that mirrors the multi-robot network structure and uses Gaussian belief propagation to synchronize local maps asynchronously without requiring a fixed communication topology.
Key results
- Relaxes tree-structured connectivity to eliminate prediction discontinuities and improve accuracy
- Achieves centralized batch-training performance through distributed, asynchronous message passing
- Outperforms distributed neural networks in accuracy, robustness to sparse communication, and continual learning
- Enables online, on-the-fly model construction with dynamic inter-robot connectivity
Why it matters
Provides a scalable and robust foundation for collaborative mapping in resource-constrained multi-robot applications like environmental monitoring and space exploration.
Abstract
We propose DistGP: a multi-robot learning method for collaborative learning of a global function using only local experience and computation. We utilise a sparse Gaussian process (GP) model with a factorisation that mirrors the multi-robot structure of the task, and admits distributed training via Gaussian belief propagation (GBP). Our loopy model outperforms Tree-Structured GPs [1] and can be trained online and in settings with dynamic connectivity. We show that such distributed, asynchronous training can reach the same performance as a centralised, batch-trained model, albeit with slower convergence. Last, we compare to DiNNO [2], a distributed neural network (NN) optimiser, and find DistGP achieves superior accuracy, is more robust to sparse communi- cation and is better able to learn continually.