This paper concentrates on the collaborative target tracking control of a
pair of tracking vehicles with formation constraints. The proposed controller
requires only distance measurements between tracking vehicles and the target.
Its novelty lies in two aspects: 1) the elliptic coordinates are used to
represent an arbitrary tracking formation without singularity, which can be
deduced from inter-agent distances, and 2) the regulation of the tracking
vehicle system obeys a binocular coordination principle, which simplifies the
design of the control law by leveraging rich physical meanings of elliptic
coordinates. The tracking system with the proposed controller is proven to be
exponentially convergent when the target is stationary. When the target drifts
with a small velocity, the desired tracking formation is achieved within a
small margin proportional to the magnitude of the target's drift velocity.
Simulation examples are provided to demonstrate the tracking performance of the
proposed controller.Comment: 6 pages, 5 figure