scholarly journals Gremlins: an Architectural Framework for Reconfigurable Autonomous Robots

2021 ◽  
Author(s):  
James Gaston
Keyword(s):  
Control System ◽  
Communication System ◽  
Communication Systems ◽  
Autonomous Robots ◽  
Fault Tolerant ◽  
Failure Detection ◽  
Base Station ◽  
Communication Strategy ◽  
Stair Climbing ◽  
Control Architecture

The work area of a team of small robots is limited by their inability to traverse a very common obstacle: stairs. We present a complete integrated control architecture and communication strategy for a system of reconfigurable robots that can climb stairs. A modular robot design is presented which allows the robots to dynamically reconfigure to traverse certain obstacles. This thesis investigates the implementation of a system of autonomous robots which can cooperatively reconfigure themselves to collectively travers obstacle such as stairs. We present a complete behaviorand communication system which facilitates this autonomous reconfiguration. The layered behavior-based control system is fault-tolerant and extends the capabilities of a control architecture known as ALLIANCE. Behavior classes are introduced as mechanism for managing ordering dependencies and monitoring a robot's progress through a particular task. The communication system compliments the behavioral control and iimplementsinherent robot failure detection without the need for a base station or external monitor. The behavior and communication systems are validated by implementing them ona mobile robot platform synthesized specifically for this research. Experimental trials showed that the implementation of the behavior control systems was successful. The control system provided robust, fault-tolerant performance even when robots failed to perform docking tasks while recongifuring. Once the robots reconfigure to form a chain, a different control scheme based on gait control tables coordinates the individual movements of the robots. Several successful stair climbing trials were accomplished. Improvements to the mechanical design are proposed.

scholarly journals Gremlins: an Architectural Framework for Reconfigurable Autonomous Robots

2021 ◽  
Author(s):  
James Gaston
Keyword(s):  
Control System ◽  
Communication System ◽  
Communication Systems ◽  
Autonomous Robots ◽  
Fault Tolerant ◽  
Failure Detection ◽  
Base Station ◽  
Communication Strategy ◽  
Stair Climbing ◽  
Control Architecture

The work area of a team of small robots is limited by their inability to traverse a very common obstacle: stairs. We present a complete integrated control architecture and communication strategy for a system of reconfigurable robots that can climb stairs. A modular robot design is presented which allows the robots to dynamically reconfigure to traverse certain obstacles. This thesis investigates the implementation of a system of autonomous robots which can cooperatively reconfigure themselves to collectively travers obstacle such as stairs. We present a complete behaviorand communication system which facilitates this autonomous reconfiguration. The layered behavior-based control system is fault-tolerant and extends the capabilities of a control architecture known as ALLIANCE. Behavior classes are introduced as mechanism for managing ordering dependencies and monitoring a robot's progress through a particular task. The communication system compliments the behavioral control and iimplementsinherent robot failure detection without the need for a base station or external monitor. The behavior and communication systems are validated by implementing them ona mobile robot platform synthesized specifically for this research. Experimental trials showed that the implementation of the behavior control systems was successful. The control system provided robust, fault-tolerant performance even when robots failed to perform docking tasks while recongifuring. Once the robots reconfigure to form a chain, a different control scheme based on gait control tables coordinates the individual movements of the robots. Several successful stair climbing trials were accomplished. Improvements to the mechanical design are proposed.

scholarly journals Evaluation of a fault-tolerant call control system

2004 ◽  
Vol 17 (1) ◽  
pp. 33-40 ◽  
Author(s):  
Marjan Bozinovski ◽  
Liljana Gavrilovska ◽  
Ramjee Prasad ◽  
Hans-Peter Schwefel
Keyword(s):  
Control System ◽  
Theoretical Analysis ◽  
Fault Tolerant ◽  
Failure Detection ◽  
Ip Multimedia Subsystem ◽  
Call Control ◽  
Signaling Protocol ◽  
The Core ◽  
Control Concept ◽  
Functional Features

The session initiation protocol (SIP) is the main signaling protocol in the 3GPP IP multimedia subsystem (IMS). The SIP sessions in IMS have to be highly reliable. The developed fault-tolerant SIP call control concept includes state-sharing mechanism, failure-detection and fail-over management. The state-sharing mechanism representing the core entity in the overall system has been developed to meet the specific SIP functional features and requirements for reliability of SIP services. Theoretical analysis and measurements in a prototype implementation showed that TFTP outperforms FTP.

scholarly journals GREEN ROUTINGSTRATEGY FOR DYNAMICALLY ARRANGED HOMOGENEOUS WSN- MSCT2

2014 ◽  
Vol 12 (7) ◽  
pp. 3712-3718
Author(s):  
Gulista Khan ◽  
Wajid Ali ◽  
Swati Arya ◽  
Vaibhav Sharma
Keyword(s):  
Wireless Networks ◽  
Sensor Network ◽  
Communication Systems ◽  
Fault Tolerant ◽  
Base Station ◽  
Ease Of Use ◽  
Sensor Nodes ◽  
Base Stations ◽  
General Terms

Wireless networks play a crucial role in the communication systems nowadays. Wireless networks are being increasingly used in the communication among devices of the most varied types and sizes. User mobility, affordability, flexibility and ease of use are few of many reasons for making them very appealing to new applications and more users everyday. A Wireless Sensor Network (WSN) is composed of sensor nodes spread over the field to sense the data. The sensed data must be gathered & transmitted to Base Station (BS) for end user queries. The used sensor nodes being in- expensive having low computation power & limited energy so are not as much reliable as their expensive macro sensor counter parts but their size and cost enable hundred to thousand of micro sensors to achieve high quality fault tolerant system. In an environment where in each round all sensor nodes have to send data to base station; it is required to effectively utilize energy of sensor nodes so as to increase the life- time of the system. The use of data aggregation & fusion as proposed in LEACH increases system lifetime by a factor of 8 as compared to conventional routing protocols. In this work, our main focus is the static sensors are randomly selected and the base stations have their information all a priori. Basically, the sensors are in direct communication range of each other and can transmit to and receive from the base station. The nodes periodically sense the environment and have always data to send in each round of communication. The nodes fuse/ aggregate the data they receive from the others with their own data, and produce only one packet regardless of how many packets they receive. The problem is to find a routing scheme or an efficient protocol to deliver data packets collected from sensor nodes to the base station. It maximizes the lifetime of the sensor network under the system model given above. However, the definition of quality of service of the sensor network provides is not specified. Secondly, where the nodes are densely deployed, the quality of the system is affected as soon as a significant amount of nodes die, since adjacent nodes record identical or related data. In this case, the lifetime of the network is the time elapsed until half of the nodes or some specified portion of the nodes die. In general terms, the time in rounds where the last node depletes all of its energy defines the lifetime of the overall sensor network. Taking these different possible requirements under consideration, our work provides a proper timing of all deaths for all algorithms in detail as well as chooses the shortest possible path for communication with better memory management scheme and leaves the decision which one to choose to system designers.

scholarly journals Cooperative beamforming for a double-IRS-assisted wireless communication system

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Guodong Tian ◽  
Rongfang Song
Keyword(s):  
Wireless Communication ◽  
Communication System ◽  
Communication Systems ◽  
Signal To Noise Ratio ◽  
Pso Algorithm ◽  
Base Station ◽  
Wireless Communication Systems ◽  
Wireless Communication System ◽  
Power Simulation ◽  
Reflecting Surface

AbstractIntelligent reflecting surface (IRS) has emerged as an innovative and disruptive solution to boost the spectral and energy efficiency and enlarge the coverage of wireless communication systems. However, the existing literature on IRS mainly concentrates on wireless communication systems assisted by single or multiple distributed IRSs, which are not always effective. In view of this issue, this paper considers a special double-IRS-assisted wireless communication system, where IRS1 and IRS2 are deployed near the base station (BS) and the user, respectively, and the transmitted signals reach the user via the cascaded BS-IRS1-IRS2-user channel only. We cooperatively optimize transmit and passive beamforming on the two IRSs based on the particle swarm optimization (PSO) algorithm to maximize the received signal power. Simulation indicates that despite no direct line-of-sight (LoS) path from the BS to the user, an excellent signal-to-noise ratio (SNR) is available at the receiver with the aid of two IRSs, which demonstrates that it is feasible to assist communication by double reflection links composed of two IRSs. Additionally, we unexpectedly find that when the positions of the two IRSs are fixed, by exchanging the positions of the BS and the user, the obtainable SNRs are similar.

scholarly journals Smart Antenna for Application in UAVs

Information ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 328 ◽  
Author(s):  
António Carneiro ◽  
João Torres ◽  
António Baptista ◽  
Maria Martins
Keyword(s):  
Control System ◽  
Unmanned Aerial Vehicle ◽  
Communication System ◽  
Smart Antenna ◽  
Base Station ◽  
Anechoic Chamber ◽  
Digital Potentiometer ◽  
Aerial Vehicle ◽  
Improved Algorithm

In the present paper, a smart planar electrically steerable passive array radiator (ESPAR) antenna was developed and tested at the frequency of 1.33 GHz with the main goal to control the main radiation lobe direction, ensuring precise communication between the antenna that is implemented in an unmanned aerial vehicle (UAV) and the base station. A control system was also developed and integrated into the communication system: an antenna coupled to the control system. The control system consists of an Arduino, a digital potentiometer, and an improved algorithm that allows defining the radiation-lobe direction as a function of the UAV flight needs. The ESPAR antenna was tested in an anechoic chamber with the control system coupled to it so that all previously established requirements were validated.

Crash Recovery for Embedded Main Memory Database

2012 ◽  
Vol 195-196 ◽  
pp. 1122-1124 ◽  
Author(s):  
Yi Bing Li ◽  
Shuang Wang ◽  
Fang Ye
Keyword(s):  
Real Time ◽  
Communication System ◽  
Communication Systems ◽  
Base Station ◽  
Main Memory ◽  
Normal Operation ◽  
Recovery Algorithm ◽  
Main Memory Database ◽  
Efficient Data ◽  
Crash Recovery

In the last years, the deployment of embedded real-time communication systems has increased dramatically. At the same time, the amount of data that needs to be managed by embedded real-time main memory databases is increasing, thus requiring an efficient data management. However, system crash will cause data loss in main memory, which will seriously affect the normal operation of the entire communication system. This paper introduces an algorithm of system crash recovery applied in main memory database of embedded real-time communication system. This paper expatiates the software architecture of SDR base station, the cause of crash occurring, and proposes the flash recovery algorithm using for system recovery. A main memory database using this algorithm has been applied in a real communication systemmultimode SDR base station communication system.

scholarly journals QoS-Aware Resource Allocation for Network Virtualization in an Integrated Train Ground Communication System

2018 ◽  
Vol 2018 ◽  
pp. 1-12
Author(s):  
Li Zhu ◽  
Fei Wang ◽  
Hongli Zhao
Keyword(s):  
Resource Allocation ◽  
Communication System ◽  
Communication Systems ◽  
Network Virtualization ◽  
Base Station ◽  
Urban Rail Transit ◽  
Normal Operation ◽  
Rail Transit ◽  
Resource Allocation Algorithm ◽  
Urban Rail

Urban rail transit plays an increasingly important role in urbanization processes. Communications-Based Train Control (CBTC) Systems, Passenger Information Systems (PIS), and Closed Circuit Television (CCTV) are key applications of urban rail transit to ensure its normal operation. In existing urban rail transit systems, different applications are deployed with independent train ground communication systems. When the train ground communication systems are built repeatedly, limited wireless spectrum will be wasted, and the maintenance work will also become complicated. In this paper, we design a network virtualization based integrated train ground communication system, in which all the applications in urban rail transit can share the same physical infrastructure. In order to better satisfy the Quality of Service (QoS) requirement of each application, this paper proposes a virtual resource allocation algorithm based on QoS guarantee, base station load balance, and application station fairness. Moreover, with the latest achievement of distributed convex optimization, we exploit a novel distributed optimization method based on alternating direction method of multipliers (ADMM) to solve the virtual resource allocation problem. Extensive simulation results indicate that the QoS of the designed integrated train ground communication system can be improved significantly using the proposed algorithm.

scholarly journals PERUBAHAN SISTEM KONTROL DARI PLC KE DCS PADA GRUP BAG FILTER 563-BF1

2019 ◽  
Vol 18 (3) ◽  
pp. 349-360
Author(s):  
Jefri Gunawan ◽  
Fatahula Fatahula ◽  
Juhartono Juhartono
Keyword(s):  
Control System ◽  
Communication System ◽  
Communication Systems ◽  
Production Loss ◽  
Bag Filter ◽  
Reliable System ◽  
Logic Control ◽  
Programmable Logic Control ◽  
Filter Group ◽  
Long Time

Bag filter is an equipment in cement industries that used for handling dust from material or separate fines dust with air to make the area is not dusty and it is not make accumulation material. Bag filter (563-BF1) is used for handling dusty area at outlet ball mill in the cement making process. The working systems of bag filter group (563-BF1) is controlled by PLC (Programmable Logic Control). However, the PLC is obsolete so it takes a long time to handle when damage occurs and causes the risk of production loss reach Rp 1,301,801,760.00. In addition, communication systems between PLC with Central Control Room (CCR) that are less reliable cause communication to fail on April 2019 so that the equipment cannot be controlled. To overcome this, it is necessary to upgrade the PLC and communication system to the latest version or change it to DCS (Distributed Control System). Upgrading PLC requires huge costs with almost the same communication system reliability. While changing the control system to DCS is cheaper with better reliable system. So, we chose to change it to DCS. After that control system is changed to DCS on April 2019, the risk of production loss can be eliminated with saving cost in the amount of Rp 220,402,885.00 and after 3 month the communication failed is never occurs (it is more reliable).

scholarly journals Joint optimization of BS-VS association and power control in secure HSR communication systems

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Hao Xu ◽  
Lu Yan ◽  
Haixiang Liu ◽  
Ke Li ◽  
Jian Wang
Keyword(s):  
Power Control ◽  
Communication System ◽  
Communication Systems ◽  
High Speed ◽  
Base Station ◽  
Base Stations ◽  
Mixed Integer ◽  
Total Power ◽  
Good Convergence ◽  
The One

AbstractIn this paper, the secure transmission for high-speed railway (HSR) communication system is studied. The considered HSR wireless communication system consists of a macro base station, B roadside base stations, and K vehicle stations (VSs) on the top of the train, and the eavesdropping user is a mobile unmanned aerial vehicle (UAV). We consider maximizing the sum of the minimum security rate of each time slot as the objective function, and the constraint conditions contain the quality of service (QoS), switch requirements and the total power constraint. The original optimization problem is mixed-integer and non-convex, it is intractable to solve directly. The block coordinate descent (BCD) method is applied, and the original problem can be decoupled into two sub-problems. The one is the joint BS-VS association problem, and the other is the power control problem. The first sub-problem of optimizing BS-VS association can be solved by the successive convex approximation (SCA) algorithm, and the second one of optimizing transmit power can be solved by the lagrangian dual method. Simulation results show that the proposed algorithms have good convergence.

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