Longitudinal Control Volumes: A Novel Centralized Estimation and Control Framework for Distributed Multi-Agent Sorting Systems
James Maier, Prasanna Sriganesh, Matthew Travers
TL;DR
This work introduces Longitudinal Control Volumes (LCV) to model material flow along a conveyor in recycling sorting facilities, enabling a low‑dimensional yet expressive state $X_k=[\mathbf{x^1_k},\dots,\mathbf{x^n_k},r_k]^T$ of dimension $nm+1$. A Kalman Filter fuses vision‑based detections into this global state, while a receding‑horizon MPC optimizes belt speed to maximize sorted value and minimize contamination over a horizon $T$, with dynamics split into motion $\mathcal{L}(r_k)$ and sorting $\mathcal{F}(\mathbf{X_k})$ operators. The approach yields substantial performance gains, with simulation and physical experiments showing $\approx 40$–$100\%$ increases in profit/value over constant‑speed baselines across 2–4 materials. The framework offers a path toward realtime centralized coordination in multi‑agent sorting and can extend to other domains, such as autonomous robots or swarm systems, where control volumes provide a scalable state representation.
Abstract
Centralized control of a multi-agent system improves upon distributed control especially when multiple agents share a common task e.g., sorting different materials in a recycling facility. Traditionally, each agent in a sorting facility is tuned individually which leads to suboptimal performance if one agent is less efficient than the others. Centralized control overcomes this bottleneck by leveraging global system state information, but it can be computationally expensive. In this work, we propose a novel framework called Longitudinal Control Volumes (LCV) to model the flow of material in a recycling facility. We then employ a Kalman Filter that incorporates local measurements of materials into a global estimation of the material flow in the system. We utilize a model predictive control algorithm that optimizes the rate of material flow using the global state estimate in real-time. We show that our proposed framework outperforms distributed control methods by 40-100% in simulation and physical experiments.
