Heterogeneous Field Robotics
Multiple Agricultural Unmanned Aerial Vehicles for Remote Sensing
In this study, we develop a multi-UAV system for agriculture using the distributed swarm control algorithm and evaluate the performance of the system. The performance of the proposed agricultural multi-UAV system is quantitatively evaluated and analyzed through four experimental cases: single UAV with autonomous control, multiple UAVs with autonomous control, single UAV with remote control, and multiple UAVs with remote control. Moreover, the performance of each system was analyzed through seven performance metrics: total time, setup time, flight time, battery consumption, inaccuracy of land, haptic control effort, and coverage ratio. Experimental results indicate that the performance of the multi-UAV system is significantly superior to the single-UAV system.
Cooperative control of heterogeneous field robots based on hybrid systems approach
Cooperative control is a major challenge that needs to be addressed for the enhanced automation of multi-robot-based field applications. Formal method-based discrete-event dynamics must be considered to systematically supervise large-scale dynamic systems such as heterogeneous field robots, and traditional control theories which primarily deal with continuous-time dynamics. Therefore, in this study, we propose a hybrid system-based supervisory cooperative control system for heterogeneous field robots. The developed hybrid system is modeled as the formal language based on automata theory and includes discrete-event dynamics in which the dynamic states are transitioned by asynchronous events. Further, behavior specifications (e.g., obstacle avoidance, task scheduling, and path following) considering the desired control of heterogeneous robots are designed to synthesize the supervisory controllers. To make a control system handle the complexity and scalability of large-scale dynamic systems, we developed a decentralized control architecture consisting of modular and hierarchical supervisors. Experimental scenarios for the cooperative control of heterogeneous field robots in dynamic simulators and outdoor fields were designed to evaluate the proposed hybrid system-based decentralized control system. In the experimental results, the proposed supervisory cooperative control system showed desired control actions such that heterogeneous field robots satisfy the behavior specifications. The hybrid-based approach, which includes discrete-event dynamics, was able to systematically analyze the dynamic changes in the system state and the corresponding control actions of the supervisors. This study presents a comprehensive approach based on hybrid systems and supervisory control theory for cooperative control of heterogeneous field robots.