scholarly journals Functional Capabilities of Coupled Memristor-Based Reactance-Less Oscillators

2021 ◽  
Author(s):  
Vladimir V. Rakitin ◽  
Sergey G. Rusakov
Keyword(s):  
Input Signal ◽  
Pulse Sequences ◽  
Main Idea ◽  
Rate Of Change ◽  
Simple Circuit ◽  
Digital Signals ◽  
Oscillator Circuit ◽  
Control Approach ◽  
Functional Capabilities ◽  
Memristor Device

New functionalities of reactance-less memristor based oscillators are discussed which arise when two elementary oscillators are connected. It is shown that the system of coupled memristor based oscillators can be used for converting analog and analog-digital signals into binary pulse sequences. The approach to control the thresholds in memristor based oscillators is discussed. Standard control approach in memristor based oscillators is the exploitation of input signal to drive the rate of change in the state of the memristor. In contrast, the main idea of the considered controlling approach is to send the input signal not directly to the memristor device but to the comparator circuit and as result to control oscillator circuit behavior by change of interval of memristor resistor variation. The capabilities of coupled memristor based oscillators with control thresholds are sufficient for constructing the simple circuit elements of oscillatory computing architectures.

Adaptive Gimbal Control Approach to Account for Power Consumption and Landmark Tracking Quality

2016 ◽  
Author(s):  
Akin Tatoglu ◽  
Claudio Campana
Keyword(s):  
Power Consumption ◽  
Input Signal ◽  
Feature Detection ◽  
Oscillation Amplitude ◽  
System Response ◽  
Indoor Environments ◽  
Tracking Accuracy ◽  
Visual Sensor ◽  
Control Approach ◽  
Landmark Tracking

Unmanned Aerial Vehicles (UAV) are commonly used for robotics research and industrial purposes. Most of the autonomous applications use visual sensors and inertial measurement units for localization. Design constraints of such systems are defined considering smooth operation requirements such as indoor environments without external forces where input tracking signal is constant during an operation. In this research paper, we simultaneously investigate and compare stability, power consumption and landmark tracking quality of a visual sensor mounted gimbal specifically for rapid UAV motion requirements where input signal continuously varies such as at obstacle rich environments. We not only attempt to find efficient control parameters but also compare these settings with power consumption and landmark tracking quality metric which are vital for mobile robots and localization algorithms. Efficiency of the system response is analyzed with rise and settling time as well as oscillation amplitude and frequencies. These parameters are tested and benchmarked with various voltage and current limitations. In addition to that, different response behaviors were investigated considering landmark tracking quality metrics including feature detection and image blur. We have shown that gimbal stabilization controller under continuously varying input signal requires less responsive behavior to keep landmark tracking accuracy stable. Initial simulation results, system development and experimental setup procedure are explained and behavior plots for each topic are listed and analyzed.

scholarly journals A Multi-Slope Sliding-Mode Control Approach for Single-Phase Inverters under Different Loads

2016 ◽  
Author(s):  
Ghazanfar Shahgholian ◽  
Babk Khajeh Shalaly
Keyword(s):  
Sliding Mode Control ◽  
Single Phase ◽  
Sliding Mode ◽  
Main Idea ◽  
Sliding Surface ◽  
Tracking Accuracy ◽  
Control Approach ◽  
Mode Control ◽  
Non Linear ◽  
Slope Function

In this paper, a new approach to the sliding-mode control of single-phase inverters under linear and non-linear loads is introduced. The main idea behind this approach is to utilize a non-linear, flexible and multi-slope function in controller structure. This non-linear function makes the controller possible to control the inverter by a non-linear multi-slope sliding surface. In general, this sliding surface has two parts with different slopes in each part and the flexibility of the sliding surface makes the multi-slope sliding-mode controller (MSSMC) possible to reduce the total harmonic distortion, to improve the tracking accuracy, and to prevent overshoots leading to undesirable transient-states in output voltage which are occurred when the load current sharply rises. In order to improve the tracking accuracy and to reduce the steady-state error, an integral term of the multi-slope function is also added to the sliding surface. The improved performance of the proposed controller is confirmed by simulations and finally, the results of the proposed approach are compared with a conventional SMC and a SRFPI controller.

scholarly journals Hybrid Ventilation System and Soft-Sensors for Maintaining Indoor Air Quality and Thermal Comfort in Buildings

Atmosphere ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 110
Author(s):  
Nivetha Vadamalraj ◽  
Kishor Zingre ◽  
Subathra Seshadhri ◽  
Pandarasamy Arjunan ◽  
Seshadhri Srinivasan
Keyword(s):  
Air Quality ◽  
Thermal Comfort ◽  
Indoor Air Quality ◽  
Predictive Control ◽  
Indoor Air ◽  
Ventilation System ◽  
Main Idea ◽  
Soft Sensors ◽  
Control Approach ◽  
Hybrid Ventilation

Maintaining both indoor air quality (IAQ) and thermal comfort in buildings along with optimized energy consumption is a challenging problem. This investigation presents a novel design for hybrid ventilation system enabled by predictive control and soft-sensors to achieve both IAQ and thermal comfort by combining predictive control with demand controlled ventilation (DCV). First, we show that the problem of maintaining IAQ, thermal comfort and optimal energy is a multi-objective optimization problem with competing objectives, and a predictive control approach is required to smartly control the system. This leads to many implementation challenges which are addressed by designing a hybrid ventilation scheme supported by predictive control and soft-sensors. The main idea of the hybrid ventilation system is to achieve thermal comfort by varying the ON/OFF times of the air conditioners to maintain the temperature within user-defined bands using a predictive control and IAQ is maintained using Healthbox 3.0, a DCV device. Furthermore, this study also designs soft-sensors by combining the Internet of Things (IoT)-based sensors with deep-learning tools. The hardware realization of the control and IoT prototype is also discussed. The proposed novel hybrid ventilation system and the soft-sensors are demonstrated in a real research laboratory, i.e., Center for Research in Automatic Control Engineering (C-RACE) located at Kalasalingam University, India. Our results show the perceived benefits of hybrid ventilation, predictive control, and soft-sensors.

scholarly journals Active-Current Control of Large-Scale Wind Turbines for Power System Transient Stability Improvement Based on Perturbation Estimation Approach

Energies ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1995 ◽  
Author(s):  
Peng Shen ◽  
Lin Guan ◽  
Zhenlin Huang ◽  
Liang Wu ◽  
Zetao Jiang
Keyword(s):  
Power System ◽  
Wind Turbines ◽  
Control Strategy ◽  
Large Scale ◽  
Transient Stability ◽  
Main Idea ◽  
Control Object ◽  
Current Control ◽  
Control Approach ◽  
Perturbation Estimation

This paper proposes an active-current control strategy for large-scale wind turbines (WTs) to improve the transient stability of power systems based on a perturbation estimation (PE) approach. The main idea of this control strategy is to mitigate the generator imbalance of mechanical and electrical powers by controlling the active-current of WTs. The effective mutual couplings of synchronous generators and WTs are identified using a Kron-reduction technique first. Then, the control object of each WT is assigned based on the identified mutual couplings. Finally, an individual controller is developed for each WT using a PE approach. In the control algorithm, a perturbation state (PS) is introduced for each WT to represent the comprehensive effect of the nonlinearities and parameter variations of the power system, and then it is estimated by a designed perturbation observer. The estimated PS is employed to compensate the actual perturbation, and to finally achieve the adaptive control design without requiring an accurate system model. The effectiveness of the proposed control approach on improving the system transient stability is validated in the modified IEEE 39-bus system.

scholarly journals Efficient predictive cruise control of autonomous vehicles with improving ride comfort and safety

2020 ◽  
Vol 53 (1-2) ◽  
pp. 18-28
Author(s):  
Defeng He ◽  
Wentao He ◽  
Xiulan Song
Keyword(s):  
Control Problem ◽  
Autonomous Vehicles ◽  
Adaptive Cruise Control ◽  
Ride Comfort ◽  
Main Idea ◽  
Driving Safety ◽  
Decision Variable ◽  
Cruise Control ◽  
Constrained Optimal Control ◽  
Control Approach

In this paper, the adaptive cruise control problem of autonomous vehicles is considered and we propose a novel predictive cruise control approach to improve driving safety and comfort of the host vehicle. The main idea of the approach is that the predicted acceleration commands of the host vehicle are stair-likely pre-planned to satisfy their changes along the same direction within the prediction horizon. The predictive cruise controller is then computed by online solving a finite horizon constrained optimal control problem with a decision variable. Besides explicitly handling safety constraints of vehicles, the obtained controller has abilities to efficiently attenuate peaks of the cruise commands while reducing computational load of online solving the optimization problem. Hence, the ride comfort and safety performances of vehicles are improved in terms of softening acceleration response and constraint satisfaction. Moreover, the ride comfort, following and safety performances of vehicles are summed with varying weights to cope with various traffic scenarios. Some classical cases are adopted to evaluate the proposed adaptive cruise control algorithm in terms of ride comfort, car-following ability and computational demand.

scholarly journals New Synchronization Method for Transmission Systems with Variable Length of Bits

2015 ◽  
Vol 61 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Juliusz Godek ◽  
Ryszard Golański ◽  
Jacek Kołodziej ◽  
Jacek Stępień
Keyword(s):  
Input Signal ◽  
Sampling Rate ◽  
Rate Adaptation ◽  
Rate Of Change ◽  
Variable Length ◽  
Transmission Systems ◽  
Synchronization Method ◽  
Signal Rate ◽  
Variable Duration ◽  
Evaluation Module

Abstract Based on the Spartan 3E evaluation module, a flexible platform for the implementation of different algorithms for A/D conversion was developed. The aim of presented work was to improve the concept of the sampling rate adaptation to the input signal rate of change in terms of practical issues including synchronization of delta codecs. The new, original synchronization method, useful in systems dedicated for transmission of variable duration of bits was proposed and experimentally verified. Performed measures and observations have shown elimination of the synchronization lose phenomenon

A Robust Control Approach to Perfect Reconstruction of Digital Signals

2007 ◽  
Vol 55 (9) ◽  
pp. 4444-4457 ◽  
Author(s):  
Petros G. Voulgaris ◽  
Christoforos N. Hadjicostis ◽  
Rouzbeh Touri
Keyword(s):  
Robust Control ◽  
Perfect Reconstruction ◽  
Digital Signals ◽  
Control Approach

The Research of the Jam Fault Features and Diagnostic Methods of the Slide Valve Oil Motive Based on DEH Data

2013 ◽  
Vol 860-863 ◽  
pp. 1791-1795
Author(s):  
Yong Xin Feng ◽  
Sun Cai ◽  
Chong Ming Song ◽  
Si Jia Wei ◽  
Jin Fu Liu ◽  
...  
Keyword(s):  
Fault Diagnosis ◽  
Steam Turbine ◽  
Input Signal ◽  
Slide Valve ◽  
Rate Of Change ◽  
Diagnostic Methods ◽  
Stable Operation ◽  
Limited Data ◽  
Fault Features ◽  
The Relationship

The jam fault diagnosis of slide valve oil motive has great significance on the safe and stable operation of steam turbine. As limited data available from DEH, the jam fault is difficultly diagnosed directly by DEH data. This paper defines insensitivity to represent the level of the jam fault of slide valve oil motive system. Through the simulation and research of the jam fault features of the slide valve oil motive, the relationship between the rate of change of the input signal and the insensitivity of the jam fault diagnosis is be found . Then jam fault diagnosis strategy based on DEH data was put forward and it shows good results with verification by the actual data.

Attitude control of inverted pendulums using reaction wheels: Comparison between using one and two actuators

2019 ◽  
Vol 234 (3) ◽  
pp. 420-429
Author(s):  
João Francisco Silva Trentin ◽  
Tiago Peghin Cenale ◽  
Samuel da Silva ◽  
Jean Marcos de Souza Ribeiro
Keyword(s):  
Attitude Control ◽  
Low Cost ◽  
Main Idea ◽  
Rigid Bodies ◽  
Rate Of Change ◽  
Reaction Wheel ◽  
External Disturbances ◽  
Inverted Position ◽  
And Control

The attitude control using reaction wheels as actuators has been one of the most popular ways to stabilize and repel external disturbances in aerospace devices. From the controlled change of the angular momentum rate of change using reaction wheels, it is possible to control the oscillation and direction rates of change of rigid bodies in space. Thus, the main idea of this article is to present a case study with different configurations of the well-known reaction wheel pendulum. The first is based on the classical configuration, and the second, a new one, a pendulum with two reaction wheels. For both configurations, proportional–integral–derivative controllers were designed and experimental devices were built to perform real-time controllers using low-cost hardware. The simulated and experimental results have shown that the pendulums were controlled using a simple controller in the inverted position and the results were satisfactory. Four performance indices were calculated to evaluate the results for each configuration. They showed that the pendulum with two reaction wheels worked better than the pendulum with one reaction wheel. Two actuators made it easier to move and control the pendulum in the inverted position.

EHK Index Method for Calculating Discrete Fourier Transform

2009 ◽  
Author(s):  
Ethar H. Khalil
Keyword(s):  
Mathematical Model ◽  
Fourier Transform ◽  
Discrete Fourier Transform ◽  
Input Signal ◽  
Output Signal ◽  
Digital Signals ◽  
Index Method ◽  
Signal Element

A new mathematical model has been achieved, for the calculation of DFT and its inversion depending on the indices which represent the shortest way for referring to the elements, pixels or pixels in each slide dealing with 1-D, 2-D, and 3-D digital signals respectively. This method indicates clearly the contribution factor of each input signal element in each output signal element.

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