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A non-holonomic Dubins-car like robot should detect, locate, and track the boundary of an a priori unknown dynamic environmental scalar field. The field is measured by an on-board sensor in a point-wise fashion at the robot’s location. The focus is on unsteady boundaries that arbitrarily evolve over time, and, e.g., may change shapes and sizes. We present a sliding mode control method for localizing and tracking such boundaries: the robot is steered to the boundary and circulates in its close proximity afterwards. The proposed control algorithm does not require estimation of the spatial gradient of the field and is non-demanding with respect to both computation and motion. Its mathematically rigorous justification is provided. The effectiveness of the proposed guidance law is confirmed by computer simulations and experiments with a real wheeled robot. [ABSTRACT FROM AUTHOR]

We present a reactive strategy for the navigation of a mobile robot in dynamic a priori unknown environments densely cluttered with moving and deforming obstacles. Mathematically rigorous analysis of this law with the proof of its global convergence is provided; its performance is confirmed by computer simulations. [ABSTRACT FROM AUTHOR]

A nonholonomic under-actuated robot with bounded control travels in a 3D region. A single sensor provides the value of an unknown scalar field at the current location of the robot. We present a new kinematic control paradigm to drive the robot to the maximizer of the field, which is different from conventionally trying to align the velocity vector with the field gradient. The proposed strategy does not employ gradient estimation and is non-demanding with respect to both computation and motion. Its mathematically rigorous analysis and justification are provided. Simulation results confirm the applicability and performance of the proposed guidance approach. [ABSTRACT FROM AUTHOR]

Abstract: We consider the problem of reactively navigating an unmanned Dubins-like robot along an equidistant curve of an environmental object based on the distance to its boundary measured perpendicularly to the robot centerline and the angle of incidence of this perpendicular to the boundary. Such a situation holds if e.g., the measurements are supplied by range sensors rigidly mounted to the vehicle body at nearly right angles, or by a single sensor scanning a nearly perpendicular narrow sector. A sliding mode control law is proposed that drives the robot at a pre-specified distance from the boundary and maintains this distance afterwards. This is achieved without estimation of the boundary curvature and holds for boundaries with both convexities and concavities. Mathematically rigorous analysis of the proposed control law is provided, including an explicit account for the global geometry of the boundary. Computer simulations and experiments with real wheeled robots confirm the applicability and performance of the proposed guidance approach. [Copyright &y& Elsevier]

We determine the shortest (minimal in length) path on a unicycle-like mobile robot in a known environment with smooth (possibly non-convex) obstacles with a constraint on curvature of their boundaries. Furthermore, we propose a new reactive randomized algorithm of robot navigation in unknown environment and prove that the robot will avoid collisions and reach a steady target with probability 1. The performance of our algorithm is confirmed by computer simulations and outdoor experiments with a Pioneer P3-DX mobile wheeled robot. [ABSTRACT FROM AUTHOR]