Search results for "TRACK"
showing 10 items of 975 documents
A multi-sensor multi-rate algorithm for motor rehabilitation with Augmented Reality devices
2016
Using Augmented Reality (AR) could offer stimuli to rehabilitation from neuro-motor disorders, since the patient can be aided in a better known reality than Virtual Reality (VR). The main goal for an AR system is to achieve a good quality of tracking the real object to align with virtual contents. Often a single sensor could not provide enough information to that end due to a low updating rate; therefore joining an other high updating rate sensor could be indispensable, but how to combine data from different sensors especially when they work all at different rates? In this paper an approach based on recursive parameter estimation, focusing on multi-rate tracking in AR devices is suggested. …
An adaptive control law for robotic manipulator without velocity feedback
2003
In this paper, a new adaptive control law is designed for robotic manipulators, based on the use of reference velocities instead of the actual ones and feedback signals generated from position errors. The law in question is suitable for trajectory tracking and positioning tasks. Its peculiarities are implementation without velocity measurements and estimation, high signal-to-noise ratio in control torques and absence of parameter drift in positioning tasks. Experimental tests are shown with the aim to confirm the validity of the control law and to illustrate its actual effects on the behaviour of the system.
Globally convergent adaptive and robust control of robotic manipulators for trajectory tracking
2004
This paper deals with a globally convergent adaptive and robust control of robotic manipulators for trajectory tracking in the presence of friction modelled as static nonlinearities. Two control loops are designed according to the cascade control scheme: (a) an inner adaptive control loop, which includes computed torque and PD control actions and friction compensation and (b) an outer robust control loop for unmodelled dynamics compensation. With reference to item (a), two friction compensation schemes are presented; one of them uses both the reference and the actual velocities, whereas the other employs only the actual velocity. Experimental tests carried out on a two-link SCARA manipulato…
A CONTROL LAW FOR ROBOTIC MANIPULATORS BASED ON A FILTERED SIGNAL TO GENERATE PD ACTION AND VELOCITY ESTIMATES
2007
This paper deals with an adaptive control law for robotic manipulators based on a filtered signal to generate both the PD action and velocity estimates of the joints, suitable for trajectory tracking tasks, with the particular aim of reducing the harmonic content of the mechanical torques developed at the joints and thus avoiding excitation of unmodelled dynamics and instability. The practical aspects relative to the implementation of the control law are considered as relevant and, consequently, are detailed. In particular, several methods suitable to compute velocity estimates are discussed and compared with the method described in the paper. All of the above methods are illustrated by mea…
Tracking Mobile Robot in Indoor Wireless Sensor Networks
2014
Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://10.1155/2014/837050 This work addresses the problem of tracking mobile robots in indoor wireless sensor networks (WSNs). Our approach is based on a localization scheme with RSSI (received signal strength indication) which is used widely in WSN. The developed tracking system is designed for continuous estimation of the robot's trajectory. A WSN, which is composed of many very simple and cheap wireless sensor nodes, is deployed at a specific region of interest. The wireless sensor nodes collect RSSI information sent by mobile robots. A range-based data fusion sche…
Adaptive Finite-Time Control for a Flexible Hypersonic Vehicle with Actuator Fault
2013
The problem of robust fault-tolerant tracking control is investigated. Simulation on the longitudinal model of a flexible air-breathing hypersonic vehicle (FAHV) with actuator faults and uncertainties is conducted. In order to guarantee that the velocity and altitude track their desired commands in finite time with the partial loss of actuator effectiveness, an adaptive fault-tolerant control strategy is presented based on practical finite-time sliding mode method. The adaptive update laws are used to estimate the upper bound of uncertainties and the minimum value of actuator efficiency factor. Finally, simulation results show that the proposed control strategy is effective in rejecting unc…
Peak Power Demand and Energy Consumption Reduction Strategies for Trains under Moving Block Signalling System
2013
Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2013/940936 Open Access In the moving block signalling (MBS) system where the tracking target point of the following train is moving forward with its leading train, overload of the substations occurs when a dense queue of trains starts (or restarts) in very close distance interval. This is the peak power demand problem. Several methods have been attempted in the literature to deal with this problem through changing train's operation strategies. However, most existing approaches reduce the service quality. In this paper, two novel approaches - …
Control and power management of Photovoltaic-battery based micro grid
2016
The growing demand for electrical power and the interruption of the power supply has paved the way for the realization of renewable based energy generation. This paper presents the control and power management of a hybrid microgrid system that comprises Photovoltaic (PV) array, battery, and local AC load, connected to the utility grid. This work focuses on the compensation of PV power reduction due to partial shading using bidirectional half bridge converter with battery storage. This system considers fulfilling the local load demand through PV production and, then, to manage the power among the battery and grid. In the proposed system, the considered power conditioning devices area boost c…
Network Arches: The World's Lightest Arch Bridges
2012
Summary Network arches have a tensile and a compressive flange with a web consisting of crossing hangers. Some of the hangers cross each other twice. The network can be seen as a very light, simply supported beam. There is little bending. There is a lot of tension in tie and hangers. The arches are well supported by hangers and wind bracing. Thus the buckling strength of the arch is high as long as few hangers relax. That is easiest to prevent when a concrete tie gives extra weight in the tie. The optimal shape of network arches is discussed. In two lane and two track network arches the biggest bending in the tie is usually the transverse bending half way between the arches. The optimal sha…
Analytical Investigation and Control System Set-up of Medium Scale PV Plants for Power Flow Management
2012
In the field of photovoltaic (PV) plants and energy conversion from renewable sources, a large part of the technical literature is more devoted to practical aspects (new solar cells, electrically driven PV panels, safety, reduction of parasitic currents, etc.) than to theoretical investigations. Despite this tendency, this paper presents a mathematical analysis of a medium scale photovoltaic power generation system connected to the distribution network and of its control system. In such a system, the conversion stage is unique due to the absence of a boost chopper. The conducted analysis leads to the interesting conclusion that the inverter used in the plant presents two degrees of freedom,…