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This paper presents new constraints for Selective Harmonic Elimination (SHE)-PWM technique utilized in single phase applications. The proposed constraints eliminate all triplen harmonic orders naturally whereas they appear in all single-phase output voltage waveforms conventionally. The specified non-triplen harmonics are also eliminated through calculation of switching angles. Five-level high switching...
Permanent Magnet Synchronous Machine (PMSM) torque control over a wide speed range is essentially an optimization problem that treats torque error minimization as the objective function with inverter voltage and current as constraints. It is usually time consuming and difficult to solve such optimization problem for closed-form solutions since torque, voltage and current equations are all non-linear...
We introduce ProbLP, a probabilistic local planner, for safe navigation of an autonomous robot in dynamic, unknown, continuous, and cluttered environments. We combine the proposed reactive planner with an existing global planner and evaluate the hybrid in challenging simulated environments. The experiments show that our method achieves a 77% reduction in collisions over the straight-line local planner...
This work presents a mixed reality environment for orthopaedic interventions that provides a 3D overlay of Cone-beam CT images, surgical site, and real-time tool tracking. The system uses an RGBD camera attached to the detector plane of a mobile C-arm, which is a typical device to acquire X-Ray images during surgery. Calibration of the two devices is done by acquiring simultaneous CBCT and RGBD scans...
The paper provides new results for testing the flow-invariance of time-dependent sets with arbitrary shapes, with respect to trajectories of continuous-time nonlinear systems. The approach represents a generalization of a criterion used in the qualitative analysis of ordinary differential equations with solutions in closed sets with hyper-rectangular form. Given a nonlinear dynamical system for investigation,...
This paper defines an optimal quadratic cost bound as a performance index for linear time varying systems subject to a finite time stability constraint. In particular, a sufficient condition for achieving such a guaranteed cost bound satisfying simultaneously the finite time stable constraint is given in terms of differential linear matrix inequalities. This condition is then exploited for the design...
For stability analysis of discrete-time arbitrary switching positive linear systems, we introduce a new class of switched copositive Lyapunov functions (abbreviated as CLFs) and we investigate their test power. The new class means “switched max-type CLFs” and it is defined by generalizing the “mode-independent max-type CLFs” (that were introduced and characterized by our previous works). This generalization...
In this paper, a guidance law for tracking straight-line segment and a constant-altitude circular orbits are proposed for a fixed wing unmanned aerial vehicle (UAV). Both guidance laws are based on the notion of vector fields, which are used to generate desired commands to the inner-loop attitude controller. Ground track heading error and lateral following error approach zero asymptotically even in...
Our article deals with the development of a robotic arm with “open control system” (for this particular application — with two degrees of freedom and possibility to add). The open control system allows, together with the known parameters of our robotic arm, to use advanced control methods. The robotic arm is controlled by a PLC and automatically generated code via tools — BR Target for Simulink. This...
This paper further develops the concept of very large size flash-memory-based pulse-width-modulation (PWM) with the implementation of an over-modulation algorithm for a three-phase inverter. The compensation of voltage for linearization is incorporated within the same flash memory with a multi-optimal PWM generator. Using flash memory demonstrates a low cost alternative to advanced processors. This...
The means for enhancing the efficiency of rocket propulsion of spacecraft considered in terms of the control of propellant consumption. The second problem lies in maximizing the safety criterion by controlling the shutdown instant of the lower-stage engine by information about the booster phantom velocity and measurements of the propellant component reserves.
In conditions of a mass character of higher education, the problems of student identification are relevant because of the differences in the contingent of students in terms of level of training, personal and cognitive characteristics. The learning process is characterized by the presence of uncertainty factors, which requires modeling and control of the application process of methods and tools of...
An approach of a new methodology for skills transfer from machine to human is proposed in this research. This methodology transmits a haptic feed-back using vibrotactile perception to transfer motor skills using a parallel planar robot and virtual reality environments. During the experimentation, the participants tried to learn a specific motion trajectory given by the system. During the process,...
Five stabilizing controls for discrete-time quasilinear control systems based on the solution of the Discrete-Time State Dependent Riccati Equation (D-SDRE) are examined. One of the approaches has been proposed by the authors and uses the approximate solution of the D-SDRE. The main goal of this paper is to obtain the results on comparative computational characteristics of the discussed control synthesis...
In the modern information society, accurate prediction of human mobility becomes increasingly essential in various areas such as city planning and resource management. With users' historical trajectories, the inherent patterns of their movements can be extracted and utilized to accurately predict the future movements. In this paper, based on a dataset of 100,000 individuals' actively uploaded location...
Urbanization is accelerating worldwide, giving rise to serious traffic problems. Traffic wave, known as stop-and go traffic or phantom intersection, is one of the most significant traffic oscillation patterns studied in Traffic Engineering. Usually these studies are numerical experiments that investigate specific places, such as a crossroad or a highway section, and their findings cannot, therefore,...
An interior permanent magnet synchronous machine drive exhibits an inherent wide speed range capability. In order to exploit this peculiar characteristic while assuring the lowest power losses, a proper control algorithm has to be used. In particular, as long as the required voltage is below the limit imposed by the available DC bus, the control algorithm must command the maximum torque per ampere...
Collaboration between heterogeneous robots can greatly improve the overall robot system by obtaining capabilities that each single robot is unable to achieve. In this paper, we present a collaborative robot system designed for search and rescue missions in an unknown environment with obstacles. The system consists of an aerial robot and a ground robot. An extended Kalman filter (EKF) is used for...
This paper proposes a basic near-environmental recognition framework based on groping for risk-tolerance disaster response robot (DRR). In extreme disaster sites, including high radiation and heavy smog, external sensors such as cameras and laser range finders do not work properly, and such sensors may be broken in accidents in the tasks. It is hoped that DRRs can continue to perform tasks, even if...
We present a quadrotor system capable of autonomously landing on a moving platform using only onboard sensing and computing. We rely on state-of-the-art computer vision algorithms, multi-sensor fusion for localization of the robot, detection and motion estimation of the moving platform, and path planning for fully autonomous navigation. Our system does not require any external infrastructure, such...
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