Observer-based feedback control for stabilization of collective motion

Abstract

Multi-vehicle control has applications in weather monitoring and ocean sampling. Previous work in this field has produced theoretically justified algorithms for stabilization of parallel and circular motions of self-propelled Newtonian particles using measurements of relative position and relative velocity. This paper describes an observer-based feedback control algorithm for stabilization of parallel and circular motions using measurements of relative position only. The algorithm utilizes information about vehicle dynamics and turning rates to estimate relative velocity.Theoretical justification is provided for the vehicle model, and numerical simulations suggest that the algorithm extends to a three-dimensional rigid body model. The algorithm has been implemented on a laboratory-scale underwater vehicle testbed, and we describe the results of experimental validation in the University of Maryland's Neutral Buoyancy Research Facility.

Towards a hyperbolic acoustic one-way localization system for underwater swarm robotics

“…A non-linear measurement function H(p) defines the receiver position as a function of available TDOAs. It consists of the components τ i j introduced by (1) and is updated by TDOA estimates (3). The EKF requires the Jacobian J H of H(p), which consists of the derivatives h i j (k) of (1):…”

“…Micro underwater vehicles have been an active research area in the recent years [1]- [3]. However, current localization approaches for experimental test tanks often do not provide satisfactory performance, particularly not for swarms.…”

“…In contrast, underwater robots have usually no access to GNSS when submerged due to the attenuation of electromagnetic waves in water. Currently, external camera systems are often the method of choice to localize underwater robots in test tanks [3] and [4]. Since image processing is performed off-board and positions are sent to the robots, the number of robots is limited by communication bandwidth and off-board processing power.…”

Fail-safe encircling of multiple unmanned aerial vehicles with bearing only measurements

“…There exists vast literature on formation control for a group of vehicles modelled by single integrator or double integrator dynamics [2][3][4][5] and by unicycles. [6][7][8][9][10][11][12][13][14][15][16][17][18] Unicycle model has close resemblance with kinematics of non-holonomic vehicles such as unmanned aerial vehicles (UAVs) and ground mobile robots. For analysing performance of guidance laws designed for the vehicles working in cooperation, it is prudent to reduce the complexity of vehicle dynamics and consider simplified model.…”

“…We present the existing work that achieves a balanced circular formation with the unicycle vehicles encircling a common centre. Paley and colleagues 6,7 have designed control laws for the stabilisation of multiple vehicles to a balanced circular formation, where each vehicle needs relative position and relative velocity information of neighbouring vehicles. Klein and Morgansen 8 and Guo et al 9 have proposed control law for encircling a moving target with multiple vehicles assuming full information about the target as well as all other agents is based on the analysis of a planar two-vehicle formation control discussed in Justh and Krishnaprasad.…”