Circumnavigation of an unknown target using UAVs with range and range rate measurements

Abstract

This paper presents two control algorithms en abling a UAV to circumnavigate an unknown target using range and range rate (i.e., the derivative of range) measurements.Given a prescribed orbit radius, both control algorithms (i) tend to drive the UAV toward the tangent of prescribed orbit when the UAV is outside or on the orbit, and (ii) apply zero control input if the UAV is inside the desired orbit. The algorithms differ in that, the first algorithm is smooth and unsaturated while the second algorithm is non-smooth and saturated. By analyzing properties associated with the bearing angle of the UAV relative to the target and through proper design of Lyapunov functions, it is shown that both algorithms produce the desired orbit for an arbitrary initial state. Two examples are provided as a proof of concept.

Elliptical Circumnavigation for Multiple Quadrotors With Regulatable Intervehicle Distance: Experimental Validation

“…In [13], a cyclic control policy is suggested for monitoring the single static target. Based on quadrotor velocity and relative distance between quadrotors and target, a circumnavigation control methodology with unknown target is advanced for quadrotors [14]. By fusion of finite-time control law, non-holonomic robots are allowed to circumnavigate the targets in finite time without considering uncertainties [15].…”