Rogelio Lozano

Bio: Rogelio Lozano is an academic researcher from University of Technology of Compiègne. The author has contributed to research in topics: Control theory & Adaptive control. The author has an hindex of 58, co-authored 496 publications receiving 14570 citations. Previous affiliations of Rogelio Lozano include University of Illinois at Urbana–Champaign & Instituto Politécnico Nacional.

Construction, Modeling and Simulation of a Mini-unmanned Aircraft in DELTA Configuration

Abstract: We present the design and construction of a UAV in delta configuration in order to accomplish certain tasks and requirements which are explained along this document. We presented too, after the construction, the dynamic model of the UAV developed, based on its structural characteristics and obtained through the Newton-Euler method. The final dynamic model is restricted to longitudinal motion to simplify the system and make it easy to simulate using a control law which will lead the system to the stabilization of the aircraft along the longitudinal axis. These simulations of the dynamic model included the control law were added to demonstrate the capability of the aircraft designed to be longitudinally stabilized.

Fusión de Flujo Óptico y Sensores Inerciales para la Estabilización de un Mini Helicóptero de Cuatro Rotores

Abstract: This paper addresses the hover flight stabilization problems of a four-rotor rotorcraft using fusion of visual information given by a single camera and inertial information obtained from an Inertial Measurement Unit. We use the optical flow in combination with the integration of gyro measurement to estimate the linear and rotational yaw velocities as well as the position and velocity of a UAV. Experimental results show a satisfactory flight performance of the four-rotor rotorcraft platform.

Dynamic analysis of an enzymatic membrane reactor

Abstract: This paper is focused on the analysis of nonlinear dynamics of an enzymatic process involving three chemical species. The work is based on the immobilization of Acetyl-cholinesterase enzyme into an artificial proteinic membrane. Our objective is to study oscillations observed in the membrane potential difference during experimental works. Stability analysis is provided for the system from a theoretical point view. Reported results allow the analysis of the profile of diffusion motion of molecules inside the membrane.

Brief paper Synchronization of bilateral teleoperators with time delay I

Abstract: Bilateral teleoperators, designed within the passivity framework using concepts of scattering and two-port network theory, provide robust stability against constant delay in the network and velocity tracking, but cannot guarantee position tracking in general. In this paper we fundamentally extend the passivity-based architecture to guarantee state synchronization of master/slave robots in free motion independent of the constant delay and without using the scattering transformation. We propose a novel adaptive coordination architecture which uses state feedback to define a new passive output for the master and slave robots containing both position and velocity information. A passive coordination control is then developed which uses the new outputs to state synchronize the master and slave robots in free motion. The proposed algorithm also guarantees ultimate boundedness of the master/slave trajectories on contact with a passive environment. Experimental results are also presented to verify the efficacy of the proposed algorithms. c 2008 Elsevier Ltd. All rights reserved.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Higher-order sliding modes, differentiation and output-feedback control

Abstract: Being a motion on a discontinuity set of a dynamic system, sliding mode is used to keep accurately a given constraint and features theoretically-infinite-frequency switching. Standard sliding modes provide for finite-time convergence, precise keeping of the constraint and robustness with respect to internal and external disturbances. Yet the relative degree of the constraint has to be 1 and a dangerous chattering effect is possible. Higher-order sliding modes preserve or generalize the main properties of the standard sliding mode and remove the above restrictions. r-Sliding mode realization provides for up to the rth order of sliding precision with respect to the sampling interval compared with the first order of the standard sliding mode. Such controllers require higher-order real-time derivatives of the outputs to be available. The lacking information is achieved by means of proposed arbitrary-order robust exact differentiators with finite-time convergence. These differentiators feature optimal asymptot...

Linear systems

Abstract: Most of the signal processing that we will study in this course involves local operations on a signal, namely transforming the signal by applying linear combinations of values in the neighborhood of each sample point. You are familiar with such operations from Calculus, namely, taking derivatives and you are also familiar with this from optics namely blurring a signal. We will be looking at sampled signals only. Let's start with a few basic examples. Local difference Suppose we have a 1D image and we take the local difference of intensities, DI(x) = 1 2 (I(x + 1) − I(x − 1)) which give a discrete approximation to a partial derivative. (We compute this for each x in the image.) What is the effect of such a transformation? One key idea is that such a derivative would be useful for marking positions where the intensity changes. Such a change is called an edge. It is important to detect edges in images because they often mark locations at which object properties change. These can include changes in illumination along a surface due to a shadow boundary, or a material (pigment) change, or a change in depth as when one object ends and another begins. The computational problem of finding intensity edges in images is called edge detection. We could look for positions at which DI(x) has a large negative or positive value. Large positive values indicate an edge that goes from low to high intensity, and large negative values indicate an edge that goes from high to low intensity. Example Suppose the image consists of a single (slightly sloped) edge: