Jorge Pomares

University of Alicante | UA · Physics, Systems Engineering and Theory of Signal

In this article, a nonlinear optimal control approach is proposed for the dynamic model of 3-DOF four-cable driven parallel robots (CDPR). To solve the associated nonlinear optimal control problem, the dynamic model of the 3-DOF cable-driven parallel robot undergoes approximate linearization around a temporary operating point that is recomputed at...

This paper presents a trajectory optimization and control approach for the guidance of an orbital four-arm robot in extravehicular activities. The robot operates near the target spacecraft, enabling its arm's end-effectors to reach the spacecraft's surface. Connections to the target spacecraft can be established by the arms through specific foothol...

Free-floating space robotic manipulators (FSRMs) are robotic arms mounted on space platforms, such as spacecraft or satellites which are used for the repair of space vehicles or the removal of noncooperating targets such as inactive material remaining in orbit. In this paper, a novel nonlinear optimal control method is applied to the dynamic model...

Triangular satellite constellations are created by three satellites which are linked through tethers. Such formations serve distributed observation space missions or the creation of high-density satellite communication networks over high-frequency bands. In a tethered multi-satellite system consisting of three-satellites in triangular formation the...

Mechatronic systems with nonlinear dynamics are met in motion transmission applications for vehicles and robots. In this article, the control problem for the nonlinear dynamics of mechatronic motion transmission systems is solved with the use of a flatness‐based control approach which is implemented in successive loops. The state‐space model of the...

This paper proposes a direct visual servoing system for spacecraft guidance in formation flying scenarios. The proposed image-based visual servoing system uses image information for planning and executing formation acquisition, reconfiguration, and maintenance maneuvers. The system assumes that LEDs are located at specific points on the satellites,...

In this article, the feedback control and stabilization problem of dual PMLSM-driven H-type gantry cranes is treated with the use of a flatness-based control method which is implemented in successive loops. Dual-drive gantry cranes can achieve high torque and high precision in the tasks’ execution. Such a type of crane can be used in several indust...

The control problem for the multivariable and nonlinear dynamics of robotic manipulators and autonomous vehicles is solved with the use of a flatness-based control approach which is implemented in successive loops. The state-space model of these robotic systems is separated into two subsystems, which are connected between them in cascading loops. E...

The control problem for the multivariable and nonlinear dynamics of unmanned rotorcrafts is treated with the use of a flatness-based control approach which is implemented in successive loops. The state-space model of 6-DOF autonomous quadrotors is separated into two subsystems, which are connected between them in cascading loops. Each one of these...

Purpose Permanent magnet synchronous spherical motors can have wide use in robotics and industrial automation. They enable three-DOF omnidirectional motion of their rotor. They are suitable for several applications, such as actuation in robotics, traction in electric vehicles and use in several automation systems. Unlike conventional synchronous mo...

Actualmente, la utilización de herramientas de simulación como ROS/Gazebo es una práctica habitual para la simulación y desarrollo de algoritmos de control para sistemas robóticos terrestres típicos. Sin embargo, en la actualidad aún no está comúnmente aceptado en la comunidad espacial. Numerosos estudios en el campo de la robótica espacial utiliza...

Purpose A distinctive feature of tilt-rotor UAVs is that they can be fully actuated, whereas in fixed-angle rotor UAVs (e.g. common-type quadrotors, octorotors, etc.), the associated dynamic model is characterized by underactuation. Because of the existence of more control inputs, in tilt-rotor UAVs, there is more flexibility in the solution of the...

In this work, we evaluate the relationship between human manipulability indices obtained from motion sensing cameras and a variety of muscular factors extracted from surface electromyography (sEMG) signals from the upper limb during specific movements that include the shoulder, elbow and wrist joints. The results show specific links between upper l...

The article proposes a nonlinear optimal control method for the dynamic model of the parallel double inverted pendulum. Three different forms of this system are considered: (i) two poles mounted on the same cart resulting into a model with four state variables and one control input, (ii) two poles mounted on the same cart resulting into a model wit...

The control problem of the rotary double inverted pendulum (double Furuta pendulum) is nontrivial because of underactuation and strong nonlinearities in the associated state‐space model. The system has three degrees of freedom (one actuated and two unactuated joints) while receiving only one control input. In this article, a novel nonlinear optimal...

Selective compliance articulated robot arms (SCARA) robotic manipulators find wide use in industry. A nonlinear optimal control approach is proposed for the dynamic model of the 4-degrees of freedom (DOF) SCARA robotic manipulator. The dynamic model of the SCARA robot undergoes approximate linearization around a temporary operating point that is re...

In this paper we evaluate the use of linear regressors to reconstruct knee angles from electromyographic signals recorded from lower-limb muscles in charge of knee flexion and extension. This neuromechanical model has been tested under two different speed conditions showing a very reliable reconstruction of knee kinematics for all participants. A g...

A direct visual-servoing algorithm for control a space-based manipulator is proposed. A two-arm manipulator is assumed as a baseline scenario for this investigation, with one of the arms performing the manipulation and the second arm dedicated to the observation of the target zone of manipulation. The algorithm relies on images taken independently...

A flatness-based control approach which is implemented in successive loops is used to solve the control problem for the multivariable and nonlinear dynamics of industrial robotic manipulators and autonomous vehicles. The state-space model of these robotic systems is separated into two subsystems, which are connected between them in cascading loops....

Tower cranes find wide use in construction works, in ports and in several loading and unloading procedures met in industry. A nonlinear optimal control approach is proposed for the dynamic model of the 4-DOF underactuated tower crane. The dynamic model of the robotic crane undergoes approximate linearization around a temporary operating point that...

In this paper, we present ARMIA: a sensorized arm wearable that includes a combination of inertial and sEMG sensors to interact with serious games in telerehabilitation setups. This device reduces the cost of robotic assistance technologies to be affordable for end-users at home and at rehabilitation centers. Hardware and acquisition software speci...

An optimization algorithm for planning the motion of a humanoid robot during extravehicular activities is presented in this paper. The algorithm can schedule and plan the movements of the two robotic arms to move the humanoid robot by using the handrails present outside the International Space Station. The optimization algorithm considers the event...

The article proposes flatness‐based control and a Kalman Filter‐based disturbance observer for solving the control problem of a robotic exoskeleton under time‐delayed exogenous disturbances. A two‐link lower‐limb robotic exoskeleton is used as a case study. It is proven that this robotic system is differentially flat. The robot is considered to be...

En este artículo se describe la formulación, implementación y experimentación de un sistema de control visual dinámico aplicado a un robot de 6 grados de libertad. Se propone una arquitectura hardware basada en FPGAs para la implementación de los controladores. Con el objetivo de limitar la latencia del controlador se ha implementado en la FPGA no...

A direct visual-servoing algorithm for control of a space-based two-arm manipulator is proposed in this paper. The algorithm can be utilized in a two-arm manipulators configuration, where one of the arms performs the manipulation and the second arm is dedicated to the observation of the target zone of manipulation. The algorithm utilizes both visua...

This paper proposes a nonlinear optimal control approach for mulitple degrees of freedom (DOF) brachiation robots, which are often used in inspection and maintenance tasks of the electric power grid. Because of the nonlinear and multivariable structure of the related state-space model, as well as because of underactuation, the control problem of th...

The article proposes a nonlinear optimal (H-infinity) control approach for a type of underactuated power-line inspection robots. To implement this control scheme, the state-space model of the power-line inspection robots undergoes first approximate linearization around a temporary operating point, through first-order Taylor series expansion and thr...

A nonlinear optimal control approach is proposed for the model of the autonomous 3-DOF laboratory helicopter. This UAV model exhibits three degrees of freedom while receiving two control inputs and stands for a benchmark nonlinear and underactuated robotic system. The helicopter's model can perform 3 rotational motions (pitch, roll and yaw turn) wh...

There is wide use of boom cranes in ports and on vessels for ships' loading and unloading. In this article a nonlinear optimal control approach is proposed for the model of offshore boom cranes. The dynamic model of the boom cranes undergoes approximate linearization with the use of Taylor series expansion around a temporary operating point which i...

A non-linear optimal (H-infinity) control approach is proposed for the dynamic model of multi-degree-of-freedom (DOF) electro-hydraulic robotic manipulators. Control of electro-hydraulic manipulators is a non-trivial problem because of their non-linear and multi-variable dynamics. In this study, the considered robotic system consists of a multi-lin...

The use of robotic limb exoskeletons is growing fast either for rehabilitation purposes or in an aim to enhance human ability for lifting heavy objects or for walking for long distances without fatigue. The article proposes a nonlinear optimal control approach for a lower-limb robotic exoskeleton. The method has been successfully tested so far on t...

The main goal of this study is to evaluate how to optimally select the best vibrotactile pattern to be used in a closed loop control of upper limb myoelectric prostheses as a feedback of the exerted force. To that end, we assessed both the selection of actuation patterns and the effects of the selection of frequency and amplitude parameters to disc...

Visual servoing is a well-known approach to guide robots using visual information[...]

The article presents a nonlinear H-infinity (optimal) control approach for the problem of the control of the spherical rolling robot. The solution of such a control problem is a nontrivial case due to underactuation and strong nonlinearities in the system’s state-space description. The dynamic model of the robot undergoes approximate linearization...

The task of robotic grasping brings together several challenges. Among them, we focus on the calculus of where gripper plates should be placed over an object’s surface in order to grasp it. To do this, we have developed a method based on visual information. The main goal is to geometrically analyse a single 3D point cloud, where the object is prese...

The article proposes a nonlinear optimal control method for the model of the wheeled inverted pendulum (WIP). This is a difficult control and robotics problem due to the system’s strong nonlinearities and due to its underactuation. First, the dynamic model of the WIP undergoes approximate linearization around a temporary operating point which is re...

Industrial and service robots deal with the complex task of grasping objects that have different shapes and which are seen from diverse points of view. In order to autonomously perform grasps, the robot must calculate where to place its robotic hand to ensure that the grasp is stable. We propose a method to find the best pair of grasping points giv...

This paper presents a direct image-based controller to perform the guidance of a mobilemanipulator using image-based control. An eye-in-hand camera is employed to perform theguidance of a mobile differential platform with a seven degrees-of-freedom robot arm. Thepresented approach is based on an optimal control framework and it is employed to contr...

An image-based servo controller for the guidance of a spacecraft during non-cooperative rendezvous is presented in this paper. The controller directly utilizes the visual features from image frames of a target spacecraft for computing both attitude and orbital maneuvers concurrently. The utilization of adaptive optics, such as zooming cameras, is a...

The article proposes a nonlinear H-infinity (optimal) control approach to the problem of control of closed-chain robotic mechanisms. The dynamic model of the closed-chain robotic mechanism undergoes approximate linearization, round a local operating point. This local equilibrium is re-calculated at each iteration of the control program and consists...

In today society, one of the most demanded challenges faced by the current educational system is the educational response to diversity in the various educational contexts. University lecturers are opening new lines of research focused on issues as social demand and current reality of produced new learning environments. The general aim of this study...

This paper presents an embedded architecture based on field programmable gate arrays technology to implement direct visual controllers. These controllers directly generate the joint torques to perform visual servoing tasks taking into account the robot dynamics. Additionally, the concept of dynamic perceptibility, which provides information about t...

Robot manipulators have multiple uses and are especially useful when dealing with complex manipulation tasks in unstructured environments. This paper presents a direct image-based controller for performing the guidance of a free-floating robot manipulator. A camera is attached to the end-effector of the manipulator and the robot is attached to a ba...

This paper describes a whole new framework to quickly develop dynamic visual servoing systems embedded in an FPGA. Parallel design of algorithms increases the precision of this kind of controller, while minimizing the response time. Additionally, a control framework to dynamically visual control robot arms is proposed. The direct image-based visual...

The categorization of Asperger syndrome has suffered criticism from its origins. Hence our decision to carry out a bibliometric study with the aim to analyse how the treatment of this topic has evolved through a set of bibliometric indicators referred to variables of scientific production (authorship, research topics and areas…) during the period 1...

This paper presents an image-based controller to perform the guidance of a free-floating robot manipulator. The manipulator has an eye-in-hand camera system, and is attached to a base satellite. The base is completely free and floating in space with no attitude control, and thus, freely reacting to the movements of the robot manipulator attached to...

This paper proposes the design and application of an immersive virtual reality system to improve and train the emotional skills of students with autism spectrum disorders. It has been designed for primary school students between the ages of 7-12 and all participants have a confirmed diagnosis of autism spectrum disorder. The immersive environment a...

The free hardware platforms have become very important in engineering education in recent years. Among these platforms, Arduino highlights, characterized by its versatility, popularity and low price. This paper describes the implementation of four laboratory experiments for Automatic Control and Robotics courses at the University of Alicante, which...

This paper describes a whole new framework to quickly develop dynamic visual servoing systems embedded in an FPGA. Parallel design of the algorithms increases the precision of this kind of controllers, whereas minimizes the response time. Embedding dynamic visual servoing algorithms converts these systems into real-time systems. Additionally, an op...

Visual information is increasingly being used in a great number of applications in order to perform the guidance of joint structures. This paper proposes an image-based controller which allows the joint structure guidance when its number of degrees of freedom is greater than the required for the developed task. In this case, the controller solves t...

This paper presents a new framework based on optimal control to define new dynamic visual controllers to carry out the guidance of any serial link structure. The proposed general method employs optimal control to obtain the desired behaviour in the joint space based on an indicated cost function which determines how the control effort is distribute...

This paper presents a novel control approach to dynamic visual servo control multi-fingered robotic hands for the manipulation performance of an object. The control approach allows the path tracking of the object motion by means of visual information and takes into account both the dynamics model of the robot hand and the grasping force of the fing...

This paper presents a new dynamic visual control system for redundant robots with chaos compensation. In order to implement the visual servoing system a new architecture is proposed which improves the system maintainability and traceability. Furthermore, high performance is obtained as a result of parallel execution of the different tasks that comp...

The current trend in the evolution of sensor systems seeks ways to provide more accuracy and resolution, while at the same time decreasing the size and power consumption. The use of Field Programmable Gate Arrays (FPGAs) provides specific reprogrammable hardware technology that can be properly exploited to obtain a reconfigurable sensor system. Thi...

Tactile sensors play an important role in robotics manipulation to perform dexterous and complex tasks. This paper presents a novel control framework to perform dexterous manipulation with multi-fingered robotic hands using feedback data from tactile and visual sensors. This control framework permits the definition of new visual controllers which a...

Event-based visual servoing is a recently presented approach that performs the positioning of a robot using visual information only when it is required. From the basis of the classical image-based visual servoing control law, the scheme proposed in this paper can reduce the processing time at each loop iteration in some specific conditions. The pro...

This paper describes a remote laboratory employed in the practical learning of the subject “Control Systems” which is taught in the Automatics and Robotics Master's degree at the University of Alicante. The application developed allows students to practice remotely different theoretical concepts using of a hardware model of a real industrial proces...

This article presents an interactive Java software platform which enables any user to easily create advanced virtual laboratories (VLs) for Robotics. This novel tool provides both support for developing applications with full 3D interactive graphical interface and a complete functional framework for modelling and simulation of arbitrary serial-link...

A large part of the new generation of computer numerical control systems has adopted an architecture based on robotic systems. This architecture improves the implementation of many manufacturing processes in terms of flexibility, efficiency, accuracy and velocity. This paper presents a 4-axis robot tool based on a joint structure whose primary use...

Traditional visual servoing systems have been widely studied in the last years. These systems control the position of the camera attached to the robot end-effector guiding it from any position to the desired one. These controllers can be improved by using the event-based control paradigm. The system proposed in this paper is based on the idea of ac...

This paper presents the use of immersive virtual reality systems in the educational intervention with Asperger students. The starting points of this study are features of these students' cognitive style that requires an explicit teaching style supported by visual aids and highly structured environments. The proposed immersive virtual reality system...