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See detailLightweight robotic arm actuated by Shape Memory Alloy (SMA) Wires
Quintanar Guzman, Serket UL; Kannan, Somasundar UL; Olivares Mendez, Miguel Angel UL et al

in 8th International Conference on Electronics, Computers and Artificial Intelligence, Ploiesti, Romania, 30 June-02 July 2016 (2016, July 01)

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See detailControl of Aerial Manipulation Vehicle in Operational Space
Kannan, Somasundar UL; Quintanar Guzman, Serket UL; Dentler, Jan Eric UL et al

in 8th International Conference on Electronics, Computers and Artificial Intelligence, Ploiesti, Romania, 30 June-02 July 2016 (2016, July 01)

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See detailA Modularization Approach for Nonlinear Model Predictive Control of Distributed Fast Systems
Dentler, Jan Eric UL; Kannan, Somasundar UL; Olivares Mendez, Miguel Angel UL et al

in 24th Mediterranean Conference on Control and Automation (MED), Athens, Greece, June 21-24, 2016 (2016, June 22)

Distributed interconnected systems are omnipresent today. The development of advanced control methods for such systems are still challenging. Herein, the real-time applicability, flexibility, portability ... [more ▼]

Distributed interconnected systems are omnipresent today. The development of advanced control methods for such systems are still challenging. Herein, the real-time applicability, flexibility, portability and ease of implementation are issues of the existing control solutions, especially for more advanced methods such as model predictive control. This paper is addressing these issues by presenting an efficient modular composition scheme for distributed fast nonlinear systems. The advantage of this modularization approach is the capability of changing control objectives, constraints, dynamics and system topology online while maintaining fast computation. This work analyzes the functions that have to be provided for a continuation generalized minimal residual method (CGMRES) model predictive controller based on the underlying control problem. The specific structure of these functions allows their decomposition into suitable fast modules. These modules are then used to recompose the functions which are required for the control of distributed systems in a computational efficient way, while maintaining the flexibility to dynamically exchange system parts. To validate this computational efficiency, the computation time of the proposed modular control approach is compared with a standard nonmodular implementation in a pursuit scenario of quadrotor unmanned aerial vehicles (UAV). Furthermore the real-time applicability is discussed for the given scenario. [less ▲]

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See detailEstimating speed profiles from aerial vision - A comparison of regression based sampling techniques
Freis, Sebastian; Olivares Mendez, Miguel Angel UL; Viti, Francesco UL

in Proceedings of the IEEE 24th Mediterranean Conference on Control and Automation (2016, June)

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See detailVision-Based Steering Control, Speed Assistance and Localization for Inner-CityVehicles
Olivares Mendez, Miguel Angel UL; Sanchez-Lopez, Jose Luis; Jimenez, Felipe et al

in Sensors (2016), 16(3), 362

Autonomous route following with road vehicles has gained popularity in the last few decades. In order to provide highly automated driver assistance systems, different types and combinations of sensors ... [more ▼]

Autonomous route following with road vehicles has gained popularity in the last few decades. In order to provide highly automated driver assistance systems, different types and combinations of sensors have been presented in the literature. However, most of these approaches apply quite sophisticated and expensive sensors, and hence, the development of a cost-efficient solution still remains a challenging problem. This work proposes the use of a single monocular camera sensor for an automatic steering control, speed assistance for the driver and localization of the vehicle on a road. Herein, we assume that the vehicle is mainly traveling along a predefined path, such as in public transport. A computer vision approach is presented to detect a line painted on the road, which defines the path to follow. Visual markers with a special design painted on the road provide information to localize the vehicle and to assist in its speed control. Furthermore, a vision-based control system, which keeps the vehicle on the predefined path under inner-city speed constraints, is also presented. Real driving tests with a commercial car on a closed circuit finally prove the applicability of the derived approach. In these tests, the car reached a maximum speed of 48 km/h and successfully traveled a distance of 7 km without the intervention of a human driver and any interruption. [less ▲]

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See detailModel Predictive Control for Spacecraft Rendezvous
Kannan, Somasundar UL; Sajadi Alamdari, Seyed Amin UL; Dentler, Jan Eric UL et al

in 4th International Conference on Control, Mechatronics and Automation ICCMA '16, Barcelona, Spain, 2016 (2016)

The current paper addresses the problem of Spacecraft Rendezvous using Model Predictive Control (MPC). The Clohessy-Wiltshire-Hill equations are used to model the spacecraft relative motion. Here the ... [more ▼]

The current paper addresses the problem of Spacecraft Rendezvous using Model Predictive Control (MPC). The Clohessy-Wiltshire-Hill equations are used to model the spacecraft relative motion. Here the rendezvous problem is discussed by trajectory control using MPC method. Two different scenarios are addressed in trajectory control. The first scenario consist of position control with fuel constraint, secondly the position control is performed in the presence of obstacles. Here the problem of fuel consumption and obstacle avoidance is addressed directly in the cost function. The proposed methods are successfully analysed through simulations. [less ▲]

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See detailAdaptive Control of Robotic arm with Hysteretic Joint
Kannan, Somasundar UL; Bezzaoucha, Souad UL; Quintanar Guzman, Serket UL et al

in 4th International Conference on Control, Mechatronics and Automation (ICCMA'16), Barcelona, Spain 2016 (2016)

This article addresses the problem of control of robotic arm with a hysteretic joint behavior. The mechanical design of the one-degree of freedom robotic arm is presented where the joint is actuated by a ... [more ▼]

This article addresses the problem of control of robotic arm with a hysteretic joint behavior. The mechanical design of the one-degree of freedom robotic arm is presented where the joint is actuated by a Shape Memory Alloy (SMA) wire. The SMA wire based actuation of the joint makes the robotic arm lightweight but at the same time introduces hysteresis type nonlinearities. The nonlinear dynamic model of the robotic arm is introduced and an Adaptive control solution is presented to perform the joint reference tracking in the presence of unknown hysteresis behavior. The Lyapunov stability analysis of the closed loop system is presented and finally proposed adaptive control solution is validated through simulation study on the proposed nonlinear hysteretic robotic arm. [less ▲]

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See detailTowards an Autonomous Vision-Based Unmanned Aerial System against Wildlife Poachers
Olivares Mendez, Miguel Angel UL; Fu, Changhong; Ludivig, Philippe et al

in Sensors (2015), 15(12), 29861

Poaching is an illegal activity that remains out of control in many countries. Based on the 2014 report of the United Nations and Interpol, the illegal trade of global wildlife and natural resources ... [more ▼]

Poaching is an illegal activity that remains out of control in many countries. Based on the 2014 report of the United Nations and Interpol, the illegal trade of global wildlife and natural resources amounts to nearly $213 billion every year, which is even helping to fund armed conflicts. Poaching activities around the world are further pushing many animal species on the brink of extinction. Unfortunately, the traditional methods to fight against poachers are not enough, hence the new demands for more efficient approaches. In this context, the use of new technologies on sensors and algorithms, as well as aerial platforms is crucial to face the high increase of poaching activities in the last few years. Our work is focused on the use of vision sensors on UAVs for the detection and tracking of animals and poachers, as well as the use of such sensors to control quadrotors during autonomous vehicle following and autonomous landing. [less ▲]

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See detailContext-based Selection and Execution of Robot Perception Graphs
Hochgeschwender, Nico UL; Olivares Mendez, Miguel Angel UL; Voos, Holger UL et al

in 20th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA'15) (2015, September)

To perform a wide range of tasks service robots need to robustly extract knowledge about the world from the data perceived through the robot’s sensors even in the presence of varying context-conditions ... [more ▼]

To perform a wide range of tasks service robots need to robustly extract knowledge about the world from the data perceived through the robot’s sensors even in the presence of varying context-conditions. This makes the design and devel- opment of robot perception architectures a challenging exercise. In this paper we propose a robot perception architecture which enables to select and execute at runtime different perception graphs based on monitored context changes. To achieve this the architecture is structured as a feedback loop and contains a repository of different perception graph configurations suitable for various context conditions. [less ▲]

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See detailVision Based Fuzzy Control Approaches for Unmanned Aerial Vehicles
Olivares Mendez, Miguel Angel UL; Campoy, Pascual

in 16th World Congress of the International Fuzzy Systems Association (IFSA) 9th Conference of the European Society for Fuzzy Logic and Technology (EUSFLAT) (2015, July)

This paper proposed the use of vision based Fuzzy control approaches for autonomous navigation tasks with Unmanned Aerial Vehicles (UAVs). It is shown the advantages of using RGB cameras as the sensor ... [more ▼]

This paper proposed the use of vision based Fuzzy control approaches for autonomous navigation tasks with Unmanned Aerial Vehicles (UAVs). It is shown the advantages of using RGB cameras as the sensor onboard UAVs and the advantages of using Fuzzy logic controllers. It is explained how to set a vision based system and how to define a Fuzzy controller for a general control approach. A specific software was design and used to develop and tune general Fuzzy control approaches. The “how-to” of this software is also explained in this paper. A methodology to how to design, developed and tune Vision based Fuzzy Control (VBFC) approaches in robotics is also presented. Furthermore, it is shown three different VBFC approaches for autonomous navigation developed using this methodology and software. Real experiments were done to validate the different approaches with different vertical takeoff and landing (VTOL) UAVs. [less ▲]

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See detailVision Based Fuzzy Control Autonomous Landing with UAVs: From V-REP to Real Experiments
Olivares Mendez, Miguel Angel UL; Kannan, Somasundar UL; Voos, Holger UL

in 23nd IEEE Mediterranean Conference of Control and Automation (MED), 2015, Torremolinos 2015, Spain (2015, June)

This paper is focused on the design of a vision based control approach for the autonomous landing task of Vertical Take-off and Landing (VTOL) Unmanned Aerial Vehicles (UAVs). Here is presented the setup ... [more ▼]

This paper is focused on the design of a vision based control approach for the autonomous landing task of Vertical Take-off and Landing (VTOL) Unmanned Aerial Vehicles (UAVs). Here is presented the setup of a simulated environment developed in V-REP connected to ROS, and its uses for tuning a vision based control approach. In this work, a Fuzzy control approach was proposed to command the UAV’s vertical, longitudinal, lateral and orientation velocities. The UAV’s pose estimation was done based on a vision algorithm and the knowledge of the landing target. Real experiments with a quadrotor landing in a moving platform are also presented. [less ▲]

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See detailVisual odometry based absolute target geo-location from micro aerial vehicle
Annaiyan, Arun UL; Yadav, Mahadeeswara; Olivares Mendez, Miguel Angel UL et al

in International Conference on Robotics, Automation, Control and Embedded Systems (RACE), 2015 (2015, February 20)

An unmanned aerial system capable of finding world coordinates of a ground target is proposed here. The main focus here was to provide effective methodology to estimate ground target world coordinates ... [more ▼]

An unmanned aerial system capable of finding world coordinates of a ground target is proposed here. The main focus here was to provide effective methodology to estimate ground target world coordinates using aerial images captured by the custom made micro aerial vehicle (MAV) as a part of visual odometery process on real time. The method proposed here for finding target's ground coordinates uses a monocular camera which is placed in MAV belly in forward looking/ Downward looking mode. The Binary Robust Invariant Scalable Key points (BRISK) algorithm was implemented for detecting feature points in the consecutive images. After robust feature point detection, efficiently performing Image Registration between the aerial images captured by MAV and with the Geo referenced images is the prime and core computing operation considered. Precise Image alignment is implemented by accurately estimating Homography matrix. In order to accurately estimate Homography matrix which consists of 9 parameters, this algorithm solves the problem in a Least Square Optimization way. Therefore, this framework can be integrated with visual odometery pipeline; this gives the advantage of reducing the computational burden on the hardware. The system can still perform the task of target geo-localization efficiently based on visual features and geo referenced reference images of the scene which makes this solution to be found as cost effective, easily implementable with robustness in the output. The hardware implementation of MAV along with this dedicated system which can do the proposed work to find the target coordinates is completed. The main application of this work is in search and rescue operations in real time scenario. The methodology was analyzed and executed in MATLAB before implementing real time on the developed platform. Finally, three case studies with different advantages derived from the proposed framework are represented. [less ▲]

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See detailAdaptive Control of Aerial Manipulation Vehicle
Kannan, Somasundar UL; Alma, Marouane; Olivares Mendez, Miguel Angel UL et al

in Porceedings of the 4th IEEE INTERNATIONAL CONFERENCE ON CONTROL SYSTEM, COMPUTING AND ENGINEERING (2014, November)

Adaptive Control of an Aerial Manipulation Vehicle is discussed here. The aerial manipulation vehicle consisting of a quadrotor and a robotic arm has a highly coupled dynamics. The nonlinear coupling ... [more ▼]

Adaptive Control of an Aerial Manipulation Vehicle is discussed here. The aerial manipulation vehicle consisting of a quadrotor and a robotic arm has a highly coupled dynamics. The nonlinear coupling introduces additional forces and moments on the quadrotor which prevents it from precisely hovering at a position and tracking of reference trajectory. A decentralized control of robotic arm and quadrotor is considered. The robotic arm is controlled by a PID approach with acceleration feedback, and the quadrotor is controlled by PD method in the inner loop and adaptive position control in the outer loop. The proposed method successfully handles the problem of hover stabilization and trajectory tracking. [less ▲]

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See detailV-REP & ROS Testbed for Design, Test, and Tuning of a Quadrotor Vision Based Fuzzy Control System for Autonomous Landing
Olivares Mendez, Miguel Angel UL; Kannan, Somasundar UL; Voos, Holger UL

in Porceedings of The International Micro Air Vehicle Conference and Competition 2014 (2014, August)

This paper focuses on the use of the Virtual Robotics Experimental Platform (V-REP) and the Robotics Operative System (ROS) working in parallel for design, test, and tuning of a vision based control ... [more ▼]

This paper focuses on the use of the Virtual Robotics Experimental Platform (V-REP) and the Robotics Operative System (ROS) working in parallel for design, test, and tuning of a vision based control system to command an Unmanned Aerial Vehicle (UAV). Here, is presented how to configure the V-REP, and ROS to work in parallel, and how to use the developed packages in ROS for the pose estimation based on vision and for the design and use of a fuzzy logic control system. It is also shown in this paper a novel vision based fuzzy control approach for the autonomous landing task on a static and on a moving platform. The control system is based on four fuzzy logic controllers (FLC) working in parallel on an external control loop based on the visual information. All the controllers were designed and tuned to command the vertical, longitudinal, lateral, and heading velocities of the UAV. [less ▲]

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See detailHMPMR strategy for real-time tracking in aerial images, using direct methods
Martinez, Carol; Campoy, Pascual; Fernando Mondragon, Ivan et al

in Machine Vision and Applications (2014), 25(5), 1283-1308

The vast majority of approaches make use of features to track objects. In this paper, we address the tracking problem with a tracking-by-registration strategy based on direct methods. We propose a ... [more ▼]

The vast majority of approaches make use of features to track objects. In this paper, we address the tracking problem with a tracking-by-registration strategy based on direct methods. We propose a hierarchical strategy in terms of image resolution and number of parameters estimated in each resolution, that allows direct methods to be applied in demanding real-time visual-tracking applications. We have called this strategy the Hierarchical Multi-Parametric and Multi-Resolution strategy (HMPMR). The Inverse Composition Image Alignment Algorithm (ICIA) is used as an image registration technique and is extended to an HMPMR-ICIA. The proposed strategy is tested with different datasets and also with image data from real flight tests using an Unmanned Aerial Vehicle, where the requirements of direct methods are easily unsatisfied (e.g. vehicle vibrations). Results show that using an HMPMR approach, it is possible to cope with the efficiency problem and with the small motion constraint of direct methods, conducting the tracking task at real-time frame rates and obtaining a performance that is comparable to, or even better than, the one obtained with the other algorithms that were analyzed. [less ▲]

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See detailUsing the Cross-Entropy method for control optimization: A case study of see-and-avoid on unmanned aerial vehicles
Olivares Mendez, Miguel Angel UL; Fu, Changhong; Kannan, Somasundar UL et al

in Control and Automation (MED), 2014 22nd Mediterranean Conference of (2014, June)

This paper presents an adaptation of the Cross-Entropy (CE) method to optimize fuzzy logic controllers. The CE is a recently developed optimization method based on a general Monte-Carlo approach to ... [more ▼]

This paper presents an adaptation of the Cross-Entropy (CE) method to optimize fuzzy logic controllers. The CE is a recently developed optimization method based on a general Monte-Carlo approach to combinatorial and continuous multi-extremal optimization and importance sampling. This work shows the application of this optimization method to optimize the inputs gains, the location and size of the different membership functions' sets of each variable, as well as the weight of each rule from the rule's base of a fuzzy logic controller (FLC). The control system approach presented in this work was designed to command the orientation of an unmanned aerial vehicle (UAV) to modify its trajectory for avoiding collisions. An onboard looking forward camera was used to sense the environment of the UAV. The information extracted by the image processing algorithm is the only input of the fuzzy control approach to avoid the collision with a predefined object. Real tests with a quadrotor have been done to corroborate the improved behavior of the optimized controllers at different stages of the optimization process. [less ▲]

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See detailOnline learning-based robust visual tracking for autonomous landing of Unmanned Aerial Vehicles
Fu, Changhong; Carrio, A.; Olivares Mendez, Miguel Angel UL et al

in Unmanned Aircraft Systems (ICUAS), 2014 International Conference on (2014, May)

Autonomous landing is a challenging and important technology for both military and civilian applications of Unmanned Aerial Vehicles (UAVs). In this paper, we present a novel online adaptive visual ... [more ▼]

Autonomous landing is a challenging and important technology for both military and civilian applications of Unmanned Aerial Vehicles (UAVs). In this paper, we present a novel online adaptive visual tracking algorithm for UAVs to land on an arbitrary field (that can be used as the helipad) autonomously at real-time frame rates of more than twenty frames per second. The integration of low-dimensional subspace representation method, online incremental learning approach and hierarchical tracking strategy allows the autolanding task to overcome the problems generated by the challenging situations such as significant appearance change, variant surrounding illumination, partial helipad occlusion, rapid pose variation, onboard mechanical vibration (no video stabilization), low computational capacity and delayed information communication between UAV and Ground Control Station (GCS). The tracking performance of this presented algorithm is evaluated with aerial images from real autolanding flights using manually- labelled ground truth database. The evaluation results show that this new algorithm is highly robust to track the helipad and accurate enough for closing the vision-based control loop. [less ▲]

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See detailRobust real-time vision-based aircraft tracking from Unmanned Aerial Vehicles
Fu, Changhong; Carrio, A.; Olivares Mendez, Miguel Angel UL et al

in Robotics and Automation (ICRA), 2014 IEEE International Conference on (2014, May)

Aircraft tracking plays a key and important role in the Sense-and-Avoid system of Unmanned Aerial Vehicles (UAVs). This paper presents a novel robust visual tracking algorithm for UAVs in the midair to ... [more ▼]

Aircraft tracking plays a key and important role in the Sense-and-Avoid system of Unmanned Aerial Vehicles (UAVs). This paper presents a novel robust visual tracking algorithm for UAVs in the midair to track an arbitrary aircraft at real-time frame rates, together with a unique evaluation system. This visual algorithm mainly consists of adaptive discriminative visual tracking method, Multiple-Instance (MI) learning approach, Multiple-Classifier (MC) voting mechanism and Multiple-Resolution (MR) representation strategy, that is called Adaptive M 3 tracker, i.e. AM 3 . In this tracker, the importance of test sample has been integrated to improve the tracking stability, accuracy and real-time performances. The experimental results show that this algorithm is more robust, efficient and accurate against the existing state-of-art trackers, overcoming the problems generated by the challenging situations such as obvious appearance change, variant sur- rounding illumination, partial aircraft occlusion, blur motion, rapid pose variation and onboard mechanical vibration, low computation capacity and delayed information communication between UAVs and Ground Station (GS). To our best knowledge, this is the first work to present this tracker for solving online learning and tracking freewill aircraft/intruder in the UAVs. [less ▲]

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See detailMonocular Visual-Inertial SLAM-Based Collision Avoidance Strategy for Fail-Safe UAV Using Fuzzy Logic Controllers
Fu, Changhong; Olivares Mendez, Miguel Angel UL; Suarez-Fernandez, Ramon et al

in Journal of Intelligent & Robotic Systems (2014), 73(1-4), 513-533

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See detailSetting up a testbed for UAV vision based control using V-REP amp; ROS: A case study on aerial visual inspection
Olivares Mendez, Miguel Angel UL; Kannan, Somasundar UL; Voos, Holger UL

in Unmanned Aircraft Systems (ICUAS), 2014 International Conference on (2014)

This paper focuses on the use of the Virtual Robotics Experimental Platform (V-REP) and the Robotics Operative System (ROS) working in parallel for design, test, and tuning of a vision based control ... [more ▼]

This paper focuses on the use of the Virtual Robotics Experimental Platform (V-REP) and the Robotics Operative System (ROS) working in parallel for design, test, and tuning of a vision based control system to command an Unmanned Aerial Vehicle (UAV). Here, is presented how to configure the V-REP and ROS to work in parallel, and the developed software in ROS for the pose estimation based on vision and for the design and use of a fuzzy logic control system. It is also explained how to interact with a virtual and a real quadrotor (QR) to command it for the specific task of aerial visual inspection task. The control system approach presented in this work is based on three fuzzy logic controllers (FLC) working in parallel on an external control loop based on the visual information. The three controllers were designed and tuned to command the vertical, longitudinal and lateral velocities of the UAV. The task to accomplish by the control system is to modify the position of the UAV in real time for the visual inspection of an object or specific parts of a structure. The virtual environment of the V-REP was used to tune manually the control system. Finally, the behavior of the tuned controllers was validated by a set of tests in a real environment with a quadrotor. [less ▲]

Detailed reference viewed: 151 (13 UL)