Extracting Initial Iterative Control Signal Based on Trajectory Primitives Matching and Combining

2017 ◽  
Vol 21 (2) ◽  
pp. 228-234
Author(s):  
Jianming Xu ◽  
◽  
Lingxin Kong ◽  
Yaodong Wang
Keyword(s):  
Iterative Learning Control ◽  
Similarity Index ◽  
Control Signal ◽  
Optimal Matching ◽  
B Splines ◽  
Control Information ◽  
Control Signals ◽  
Primitive Sequences ◽  
Definition Of ◽  
Iterative Control

The initial iterative control signal is often adopted a zero or a certain value in the conventional iterative learning control (ILC) system, and an ILC process needs to renew again as long as the desired trajectory is changed. In this paper, the NURBS (Non-Uniform Rational B-Splines) model is used for describing all trajectory primitives and the desired trajectory. It is studied that the problem of the initial iterative control signal is extracted in ILC, which presents a method of extracting the initial iterative control signal based on the trajectory primitive optimal matching and combining algorithm. Firstly, the definition of the similarity index between the two different spacial trajectories is introduced. Secondly, an optimal matching and combining algorithm is designed under a certain similarity index, which is used to find two or more combined primitive sequences with space patterns similar to the desired trajectory. Thirdly, the initial iterative control signals of the desired trajectory are extracted by using the control information of the combined primitive sequences. Finally, the simulation is carried out to demonstrate the effectiveness of the present method.

Privacy Revisited

2010 ◽  
pp. 135-151
Author(s):  
Kirsten Martin
Keyword(s):  
Social Networking ◽  
Business Strategies ◽  
Technological Environment ◽  
Control Information ◽  
Successful Business ◽  
Definition Of

The underlying concept of privacy has not changed for centuries, but our approach to acknowledging privacy in our transactions, exchanges, and relationships must be revisited as our technological environment – what we can do with information – has evolved. The goal of this chapter is to focus on the debate over the definition of privacy as it is required for other debates and has direct implications to how we recognize, test, and justify privacy in scholarship and practice. I argue privacy is best viewed as the ability of an individual to control information within a negotiated zone. I illustrate this view of privacy through an analysis of Facebook’s Beacon program and place the case in the context of both privacy violations and successful business strategies. I find privacy zones are illuminating for situations from 10th century England to current social networking programs and are useful in identifying mutually beneficial solutions among stakeholders.

On the Literature of B-Spline Interpolation Functions

2009 ◽  
pp. 214-222
Author(s):  
Carlo Ciulla
Keyword(s):  
Scientific Community ◽  
Polynomial Interpolation ◽  
Spline Interpolation ◽  
Spline Functions ◽  
Great Effort ◽  
Formal Definition ◽  
B Spline ◽  
B Splines ◽  
Scientific Disciplines ◽  
Definition Of

This chapter reviews the extensive and comprehensive literature on B-Splines. In the forthcoming text emphasis is given to hierarchy and formal definition of polynomial interpolation with specific focus to the subclass of functions that are called B-Splines. Also, the literature is reviewed with emphasis on methodologies and applications of B-Splines within a wide array of scientific disciplines. The review is conducted with the intent to inform the reader and also to acknowledge the merit of the scientific community for the great effort devoted to B-Splines. The chapter concludes emphasizing on the proposition that the unifying theory presented throughout this book has for what concerns two specific cases of B-Spline functions: univariate quadratic and cubic models.

Effectiveness of the eastern grey kangaroo foot thump for deterring conspecifics

2005 ◽  
Vol 32 (7) ◽  
pp. 649 ◽  
Author(s):  
Helena Bender
Keyword(s):  
Background Noise ◽  
Noise Control ◽  
Control Signal ◽  
Wild Populations ◽  
Target Species ◽  
Primary Industry ◽  
Control Signals ◽  
Grey Kangaroo ◽  
Natural Sound

Overabundant wild populations of herbivores often present challenges to primary industry, competing with stock, and damaging crops and property. Eastern grey kangaroos (Macropus giganteus) are one of seven macropodid species that are considered a problem in agriculture in Australia. Most deterrent devices available commercially use sounds that do not occur in nature (i.e. artificial sounds), which often have a short-lived or no effect on the target species, whereas trials with biologically significant sounds are often more effective and provide greater resistance to habituation. I used a playback trial of an eastern grey kangaroo foot thump, a biologically significant signal that is given in response to a predator and is usually followed by flight. I determined its effectiveness compared with a recording of background noise (control) for deterring kangaroos over a seven-week period. Kangaroos significantly increased their vigilance levels in response to the foot thump, but not in response to the control signal. Just over 60% of kangaroos took flight in response to the foot thump and the control signals, but more kangaroos took flight in the first 3 s when the foot thump was played. The foot thump shows potential as a deterrent of eastern grey kangaroos for primary industry, and is less likely to suffer from habituation because it is a natural sound.

scholarly journals Digital Watermarks with Adaptive Information Ring Width in the Issue of Hidden Transmission of a Control Signal in the Multi-Target Robotic System

2020 ◽  
Vol 24 (2) ◽  
pp. 136-152
Author(s):  
O. O. Shumskaya ◽  
A. О. Iskhakova
Keyword(s):  
Ring Width ◽  
Digital Watermark ◽  
Robotic System ◽  
Control Signal ◽  
Image Rotation ◽  
Control Signals ◽  
Multi Agent ◽  
Digital Watermarks ◽  
Transmitted Signal ◽  
Hidden Data

Purpose of research. The article is devoted to the issue of ensuring the safe transmission of control signals between the elements of a multi-agent robotic system. The purpose of the work is to provide hidden data transmission with the possibility of unambiguous extraction of control signals.Methods. To solve the task set, an algorithm based on the methods of digital watermarks and digital steganography was proposed. The method of forming a digital watermark in the form of a ring with symmetry allows not only ensuring maximum imperceptibility of embedding (insignificant distortion of the container during concealment), but also to protect the transmitted signal from such complex distortions as image rotation. The steganographic concealment method allows regulating the intensity of embedding using the force factor; it is computationally simple and straightforward. The proposed approach to identifying and understanding the transmitted signal differs from modern methods of cryptography and steganalysis in that it does not require 100% correct signal extraction. After several modifications, the method allows minimizing the time spent on formation (adaptive width of the ring with signal bits) and embedding of a digital watermark (minimization of the processed area of the container for embedding).Results. The proposed approach makes it possible to transmit control signals in a hidden way within the framework of the transmission of digital objects; the conducted experiments have shown that the control signal is unambiguously understood even with such distortions as a decrease or increase in contrast or brightness, image rotation, and compression.Conclusion. Application of the proposed technique for transmitting control signals in a multi-agent robotic system will male it possible to receive the necessary information timely and safe, with a minimum probability of loss.

scholarly journals Optimisation of Energy Use in Bioethanol Production Using a Control Algorithm

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 282
Author(s):  
Jarosław Knaga ◽  
Stanisław Lis ◽  
Sławomir Kurpaska ◽  
Piotr Łyszczarz ◽  
Marcin Tomasik
Keyword(s):  
Energy Consumption ◽  
Pid Controller ◽  
Control Algorithm ◽  
Control Signal ◽  
Control Algorithms ◽  
Signal Quality ◽  
Control Signals ◽  
And Control ◽  
Rectification Process

In this work, the possibility of limiting energy consumption in the manufacturing process of bioethanol to obtain biofuel was analysed. For this purpose, a control algorithm has been optimised while retaining the good quality of the control signals. New in this study is the correlation of the control algorithm not only with the signal’s quality, but also with the energy consumption in such an energy-intensive process as rectification. The rectification process in a periodic production system has been researched. The process was modelled on a test station with the distillation mixture capacity of 25 dm3. For the optimization, the following control algorithms have been applied: relay, PID and PID after modification to I-PD. The simulation was carried out on a transfer function model of the plant that has been verified on a real object, a rectification column. The simulations of energy consumption and control signal’s quality have been carried out in the Matlab®-Simulink environment after implementing the model of the research subject and control algorithms. In the simulation process, an interference signal with an amplitude of 3% and frequency of 2 mHz was used. The executed analyses of the control signal quality and the influence of the control algorithm on the energy consumption has shown some essential mutual relationships. The lowest energy consumption in the rectification process can be achieved using the I-PD controller—however, the signal quality deteriorates. The energy savings are slightly lower while using the PID controller, but the control signal quality improves significantly. From a practical point of view, in the considered problem the best control solution is the classic PID controller—the obtained energy effect was only slightly lower while retaining the good quality of the control signals.

SOME REMARKS ABOUT THE CONNECTION BETWEEN FRACTIONAL DIVIDED DIFFERENCES, FRACTIONAL B-SPLINES, AND THE HERMITE–GENOCCHI FORMULA

2008 ◽  
Vol 06 (02) ◽  
pp. 279-290 ◽  
Author(s):  
PETER MASSOPUST ◽  
BRIGITTE FORSTER
Keyword(s):  
Natural Extension ◽  
Divided Differences ◽  
Short Paper ◽  
Difference Operators ◽  
Fractional Difference ◽  
B Splines ◽  
Definition Of

Fractional B-splines are a natural extension of classical B-splines. In this short paper, we show their relations to fractional divided differences and fractional difference operators, and present a generalized Hermite–Genocchi formula. This formula then allows the definition of a larger class of fractional B-splines.

scholarly journals Control Signal Analysis of Four Ring Space Stabilized Platform

2022 ◽  
Vol 2160 (1) ◽  
pp. 012025
Author(s):  
Minghao Gao ◽  
Yunhui Ning ◽  
Yujie Wang ◽  
Gaoling Song ◽  
Zhipeng Zheng
Keyword(s):  
Signal Analysis ◽  
Research Method ◽  
Spatial Layout ◽  
Stability Control ◽  
Physical Design ◽  
Control Signal ◽  
Control Loop ◽  
Control Signals ◽  
Stabilized Platform ◽  
Ring Space

Abstract In order to build a four ring space stable platform using free rotor gyroscope, the spatial layout of gyroscope and frame axis should be briefly analyzed, and the installation shafting should be orthogonal or perpendicular to each other to facilitate control and decoupling. On this basis, through the sensitive angle analysis of gyro and frame shafting, the control signals acting on each frame are deduced. Finally, through the physical design of the control loop of the space stability platform, the correctness of the research method and design form is demonstrated, which has theoretical guiding significance for the design of the space stability control loop.

Computation of Approximately Optimal Control Signals for Systems With Time Delays

1974 ◽  
Vol 96 (3) ◽  
pp. 269-276
Author(s):  
L. B. Horwitz
Keyword(s):  
Optimal Control ◽  
Time Delays ◽  
Computational Algorithm ◽  
Optimal Control Problems ◽  
Control Signal ◽  
Control Problems ◽  
Piecewise Constant ◽  
Switching Times ◽  
Control Signals ◽  
Approximate Nature

A computational algorithm is presented for a class of optimal control problems involving time delays. The approach is to restrict the control signal to a class of piecewise constant time functions with a prescribed number of switching times, compute the optimal member of this class, and then repeat with a larger number of switching times. By allowing the number of switching times to increase beyond bound a sequence of restricted optimal control signals is developed whose limit approaches the unrestricted optimal control signal. In practice the computations are terminated after a finite number of repeats, thus leading to the approximate nature of the solution. The results of two examples are included to illustrate the technique.

scholarly journals Online Signature Verification Based on a Single Template via Elastic Curve Matching

Sensors ◽  
2019 ◽  
Vol 19 (22) ◽  
pp. 4858
Author(s):  
Hu ◽  
Zheng ◽  
Zhan ◽  
Tang
Keyword(s):  
Signature Verification ◽  
Curve Matching ◽  
Optimal Matching ◽  
Elastic Curve ◽  
Similarity Transformations ◽  
Online Signature ◽  
Definition Of ◽  
Verification Systems ◽  
Curve Similarity ◽  
Reference Signature

Person verification using online handwritten signatures is one of the most widely researched behavior-biometrics. Many signature verification systems typically require five, ten, or even more signatures for an enrolled user to provide an accurate verification of the claimed identity. To mitigate this drawback, this paper proposes a new elastic curve matching using only one reference signature, which we have named the curve similarity model (CSM). In the CSM, we give a new definition of curve similarity and its calculation method. We use evolutionary computation (EC) to search for the optimal matching between two curves under different similarity transformations, so as to obtain the similarity distance between two curves. Referring to the geometric similarity property, curve similarity can realize translation, stretching and rotation transformation between curves, thus adapting to the inconsistency of signature size, position and rotation angle in signature curves. In the matching process of signature curves, we design a sectional optimal matching algorithm. On this basis, for each section, we develop a new consistent and discriminative fusion feature extraction for identifying the similarity of signature curves. The experimental results show that our system achieves the same performance with five samples assessed with multiple state-of-the-art automatic signature verifiers and multiple datasets. Furthermore, it suggests that our system, with a single reference signature, is capable of achieving a similar performance to other systems with up to five signatures trained.

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