Rogelio Lozano

Passivity based control for a quadrotor UAV transporting a cable-suspended payload with minimum swing

In the present work a mathematical model and a control methodology for a special class of underactuated mechanical system, composed by an Unmanned Aerial Vehicle (UAV) kind quadrotor transporting a cable-suspended payload, is proposed. The Euler-Lagrange formulation is used to derive the dynamic model of the system, where the integrated dynamics of the quadrotor, cable and payload are considered. An Interconnection and Damping Assignment-Passivity Based Control (IDA-PBC) for a quadrotor UAV transporting a cable-suspended payload is developed. The control law designed does not depend on the swing angle of the cable. The control objective is to transport the payload from point to point, with swing suppression along trajectory. Experimental results are shown to evaluate the proposed control law.

IDA-PBC methodology for a quadrotor UAV transporting a cable-suspended payload

This paper presents results on the modeling and control for an Unmanned Aerial Vehicle (UAV) kind quadrotor transporting a cable-suspended payload. The mathematical model is based on Euler-Lagrange formulation, where the integrated dynamics of the quadrotor, cable and payload are considered. An Interconnection and Damping Assignment Passivity - Based Control (IDA-PBC) for a quadrotor UAV transporting a cable-suspended payload is designed. The control objective is to transport the payload from point to point transfer with swing suppression along trajectory. The cable is considered rigid. Numerical simulations are carried out to validate the overall control approach.

Quadrotor aerial manipulator based on dual quaternions

This work presents the modeling and control of an aerial manipulator based on a quadrotor with a robotic arm using the dual quaternion approach. First the kinematic model of the complete system is obtained using dual quaternions to represent multiple rotations and translations, then the dynamic model is developed via the Newton-Euler formalism. A position control law is used to stabilize the vehicle around a desired position and orientation using a smooth trajectory. The closed-loop system is then numerically simulated to corroborate stability. In addition, experimental flight tests were performed for validation.

Swing-attenuation for a quadrotor transporting a cable-suspended payload

This paper presents the problem of safe and fast transportation of packages by an Unmanned Aerial Vehicle (UAV) kind quadrotor. A mathematical model and a control strategy for a special class of underactuated mechanical systems, composed of a quadrotor transporting a cable-suspended payload, are proposed. The Euler-Lagrange formulation is used to obtain the dynamic model of the system, where the integrated dynamics of the quadrotor, cable and payload are considered. An Interconnection and Damping Assignment-Passivity Based Control (IDA-PBC) is chosen because of its inherent robustness against parametric uncertainty and unmodeled dynamics. Two cases are considered to obtain two different control laws, in the first case, the designed control law depends on the swing angle of the payload, in the second case the control law does not depend on it. The control objective is to transport the payload from point to point, with swing reduction along trajectory. Experimental results using monocular vision based navigation are shown to evaluate the proposed control law.

Singularly perturbed implicit control law for linear time-varying delay MIMO systems: SINGULARLY PERTURBED IMPLICIT CONTROL LAW FOR LTVR MIMO SYSTEMS

This paper considers the problem of stabilizing amulti-inputmulti-output linear time varying system using a singularly perturbed controller and a model matching controller. The closed loop is a linear singularly perturbed system with uniform asymptotic stability behavior. We calculate bounds ε ∈ (0, ε*) as in the book of Kokotović, Khalil and OReilly, such that the uniform asymptotic stability of the singularly perturbed system is guaranteed.

Design and Control of an Autonomous Underwater Vehicle (AUV-UMI)

This paper outlines the conception, modeling and control of a rover type modular mini submarine. The development and implementation of the mechanical structure as well as the embedded electronics is described. The onboard instrumentation and sensors required to collect data on the environment and on its own position and orientation are also described. The mathematical representation to describe the movement of an underwater vehicle is analyzed considering the characteristics and limitations of the underwater robot. Furthermore, a control algorithm is implemented based on Lyapunov theory and Backstepping Integral Adaptive (BIA). This control strategy stabilizes the vehicle in position and orientation. The proposed control algorithm is validated in numerical simulations as well as in experimental tests which confirm the good performance of the prototype and the controller.

Robust controls for upper limb exoskeleton, real-time results

This article shows the development of an exoskeleton for human joint. The exoskeleton proposed was developed for rehabilitating individuals who have suffered injuries at their shoulders, by rehabilitation exercises. The exoskeleton has special characteristics to deal with the 5 degrees of freedom of the human shoulder. The dynamic model results in the following form: q ·· = f ( q , q · ) + b ( q ) u , where q , u , f ( q , q · ) and b ( q ) are state’s vector, torque’s vector, a matrix function and a vector function, respectively. Therefore, we applied four different control laws, among which stand two robust controls (adaptive sliding modes and proportional–derivative with adaptive gravity compensation). The adaptive controller properties allow the exoskeleton to adapt to different humans with different parameters such as size, length, weight and so on that, in mathematical terms, is represented as a mechanical system with uncertainties.

Adaptive quaternion control of a 3-DOF inertial stabilised platforms

ABSTRACT Inertial stabilised platforms are increasingly popular with a large range of products available mainstream. Most items are controlled using popular algorithms that sometimes do not offer best achievable performances. Present paper proposes an advanced control which aims at improving these latter. The exposed solution is based on quaternion representation and self-adapts to the characteristics of the payload it tries to stabilise. Proposed control law ensures the stability of the system whatever the required orientation path is. Although only simulation has been performed to check the performances of such control, results look very promising compared to non-adaptive controls and may help to construct more polyvalent and efficient gimbals which would further facilitate their expansion. Proposed control law can also be applied, as is, to every system that shares the same quaternion-based rotational dynamics.

Quaternion Kalman filter for inertial measurement units

This paper presents a theoretical and practical implementation of a Kalman Filter (KF) to obtain the attitude and angular velocity from a nine degrees of freedom (DoF) inertial measurement unit (IMU). These include three DoF from an accelerometer, three from a magnetometer and the last three from a gyroscope. It differs from other attitude filters in two main aspects, the model representation and how the information is acquired from the IMU. The quaternion model presented has an analogous linear representation that can be used, in conjunction with the the an algorithm that is presented in order to extract the attitude information from the IMU, leading to a considerable lower computational cost in order to avoid the calculation of Jacobians matrices or gradients.

Autonomous take-off and landing on a colored platform

This paper presents a novel autonomous take-off and landing approach which uses a discrete-time finite-horizon suboptimal nonlinear control strategy to achieve a smooth landing on specific colored platform. By color-based tracking we can improve the performance of the position landing by correcting the position given by the GPS. The signal of the GPS is not always reliable since the accuracy strongly depends on the environment situation and the correction by vision servoing is then necessary. Experimental results using the proposed approach show a better performance than those where the GPS signal is only used to perform the take-off and landing tasks in a completely autonomous way in presence of wind gusts.