Final colloquium Shashank Dilip Kumar

Hierarchical Control for Multi-Robot Systems using Contracts

Supervisor: Dr. Manuel Mazo Espinosa

Abstract: Modern control systems require control strategies that can handle multiple levels of abstraction while providing formal guarantees of system behaviour. Traditional hierarchical control approaches often lack formal interfaces between different layers of abstraction, making it challenging to ensure system-wide properties and extend implementations across different platforms.

This thesis presents a contract-based hierarchical control framework that provides formal guarantees across different layers of abstraction. Building upon recent developments in vertical contracts with heterogeneous refinements, we develop a three-layer control architecture for robot surveillance tasks, decomposing the problem into motion planning, trajectory generation, and tracking control. Each layer operates at its own time scale and uses appropriate model abstractions, with contracts ensuring system-wide guarantees while vertical system relationships enable proper interfacing between layers.

We validate our framework through both simulation studies and physical implementation on Elisa3 robots. The simulation results demonstrate the framework's ability to satisfy high-level temporal logic specifications while maintaining guarantees at each layer. The physical implementation reveals practical challenges in transitioning from simulation to hardware, leading to adaptations in the control architecture that maintain theoretical guarantees while accommodating hardware constraints.