Circumnavigation on Multiple Circles Around a Nonstationary Target With Desired Angular Spacing.

Area of Science:

• Robotics
• Control Theory
• Multi-agent Systems

Background:

• Existing protocols struggle with nonholonomic constraints for multi-agent circumnavigation.
• Cooperative control is essential for coordinated agent behavior around dynamic targets.

Purpose of the Study:

• To develop a cooperative protocol for nonholonomic agents to achieve multi-circular circumnavigation around a nonstationary target.
• To generalize circumnavigation for unicycle agents with desired angular spacing.
• To address challenges posed by nonholonomic constraints and target motion uncertainty.

Main Methods:

• A cooperative protocol is designed based on desired geometric formations.
• A fixed-time consensus estimator under a cyclic digraph is employed for inter-agent synchronization.
• A tracking controller is implemented to ensure zero error convergence and bounded control effort.

Main Results:

• The proposed algorithm enables agents to achieve multi-circular circumnavigation with specified angular separations.
• Fixed-time estimators successfully handle partial information and unknown target dynamics (acceleration, angular velocity).
• Numerical examples validate the controller's effectiveness in achieving the desired formation and tracking objectives.

Conclusions:

• The developed cooperative protocol effectively solves the multi-circular circumnavigation problem for nonholonomic agents.
• The approach guarantees precise formation control and bounded control effort, even with uncertain target motion.
• This work advances multi-agent coordination strategies for complex dynamic environments.