Multiple Autonomous Systems Research Articles

Guided Attention For Autonomous System Supervision

Significant increases in automation and vehicle autonomy are expected to transform today’s operators of single unmanned vehicles performing single missions into tomorrow’s supervisors of multiple autonomous systems performing multiple missions. What displays and tools will those future supervisors require, given that they will manage automation that is deterministic and brittle in the dynamic and unpredictable battlespaces of the future? To help mitigate the shortfalls of automation for the future supervisor, we focus on how to make the scope of the events handled by automation explicit to the supervisor. Here, we explore the highlighting of different event attributes, including scope, to guide attention during supervision, and we investigate aspects of geospatial integration and tradeoffs in how the highlighting is applied. These concepts are developed and applied in the domain of unmanned aerial vehicles (UAVs) guided by path planning automation-mediated routes. In a study, participants monitored multiple concurrent missions, and triaged events varying in severity and automation scope, to decide when to intervene. Four different methods of guiding attention were contrasted. Events were (1) in a callout separated from a map, (2) integrated into the map, (3) map-integrated and categorized by priority but not task-tailorable, or (4) map-integrated, categorized, and task- tailorable. Monitoring was fastest and most accurate for categorized and tailorable events, validating the utility of the attentional guidance. These two conditions traded off in the support they provided, however. Monitoring was significantly faster for tailorable vs. categorized events; however, a significant time cost for correctly configuring the tailorable guidance reduced its advantage. This study validates a novel approach for conveying automation scope, and elucidates the need to design and validate new concepts for the specific task needs of the future autonomous systems supervisor.

QoS routing across multiple autonomous systems using the path computation element architecture

We examine various algorithms for calculating quality of service (QoS)-enabled paths spanning multiple autonomous systems (ASs) using the path computation element (PCE) architecture. The problem is divided into two parts. We first calculate an AS path, then the node-by-node path. Using extensive simulation, we compared various AS-path calculation algorithms based on border gateway protocol (BGP) and various AS-aggregation procedures, such as mesh, star and nodal aggregation. For node-to-node path calculation, we employed the per-domain backward algorithm and the per-domain backward tree algorithm (also known as backward recursive PCE-based computation). Results point to the fact that complex AS-path calculation algorithms do not perform significantly better than BGP. However, if the service quality provided by ASs varies greatly, either in time or space, then we expect a QoS-aware AS-path computation algorithm, e.g., static nodal aggregation, to outperform BGP. Although the per-domain backward tree algorithm generally performs better than the per-domain backward algorithm, using a persistent variant of the latter makes it outperform the per-domain backward tree algorithm. The cost is a negligible increase in computational complexity and a slightly increased connection setup delay.

Message-Based Approach to Master Data Synchronization among Autonomous Information Systems

The evolution of networks and large scale information systems has led to the rise of data sources that are distributed, heterogeneous, and autonomous. As a result, the management of Master Data becomes more complex and of uncertain quality. This paper presents a novel message-based approach to the synchronization of Master Data among multiple autonomous information systems. Different than traditional approaches based on database triggers, the author adopts the optimistic bidirectional strategy with the process of two synchronization phases. By means of data service buses, it propagates synchronized Master Data through messages being passed along star-like cascading routes. Moreover, this approach could resolve possible data conflicts automatically using predefined attribute confidences and deducible current value confidences respectively. Finally, this paper presents the real case about synchronizing datasets among four separate but related systems based on the author’s novel message-based approach.

An Autonomous Mobile Robotics Testbed: Construction, Validation, and Experiments

This paper describes design and construction of an Autonomous Mobile Robotics Systems Testbed in detail. The testbed is an indoor experimental platform for developing and validating theoretical as well as practical research work in identification, coordinative and cooperative control, trajectory generation, computational intelligence, and sensing for multiple autonomous mobile robotics systems. It provides a designated space for multiple mobile robots while tracking their position and orientation in real-time using an overhead vision system. Several problems encountered in developing the testbed such as multi-camera color consistency, radial lens distortion, hat pattern design are clearly addressed. The testbed is analyzed for its performance and several experiments with ER1 mobile robots are presented.

A service-oriented system for distributed data querying and integration on Grids

Data Grids rely on the coordinated sharing of and interaction across multiple autonomous database management systems. They provide transparent access to heterogeneous and autonomous data resources stored on Grid nodes. Data sharing tools for Grids must include both distributed query processing and data integration functionality. This paper presents the implementation of a data sharing system that (i) is tailored to data Grids, (ii) supports well established and widely spread relational DBMSs, and (iii) adopts a hybrid architecture by relying on a peer model for query reformulation to retrieve semantically equivalent expressions, and on a wrapper-mediator integration model for accessing and querying distributed data sources. The system builds upon the infrastructure provided by the OGSA-DQP distributed query processor and the XMAP query reformulation algorithm. The paper discusses the implementation methodology, and presents empirical evaluation results.

A Prey Catching and Predator Avoidance Neural-Schema Architecture for Single and Multiple Robots

The paper presents a biologically inspired multi-level neural-schema architecture for prey catching and predator avoidance in single and multiple autonomous robotic systems. The architecture is inspired on anuran (frogs and toads) neuroethological studies and wolf pack group behaviors. The single robot architecture exploits visuomotor coordination models developed to explain anuran behavior in the presence of preys and predators. The multiple robot architecture extends the individual prey catching and predator avoidance model to experiment with group behavior. The robotic modeling architecture distinguishes between higher-level schemas representing behavior and lower-level neural structures representing brain regions. We present results from single and multiple robot experiments developed using the NSL/ASL/MIRO system and Sony AIBO ERS-210 robots.

Inter-autonomous system provisioning for end-to-end bandwidth guarantees

This paper addresses the issue of provisioning end-to-end bandwidth guarantees across multiple Autonomous Systems (ASes). We first review a cascaded model for negotiating and establishing service level agreements for end-to-end bandwidth guarantees between ASes. We then present a network dimensioning system that uses traffic engineering mechanisms for the provisioning of end-to-end bandwidth guarantees. The network dimensioning system solves two problems: (1) the economic problem of how to determine the optimum amount of bandwidth that needs to be purchased from adjacent downstream ASes at a minimum total cost; (2) given the available bandwidth resources within and beyond the AS as a result of (1), the engineering problem of how to assign bandwidth guaranteed routes to the predicted traffic while optimizing the network resource utilization. We formulate both as integer-programming problems and prove them to be NP-hard. An efficient genetic algorithm and an efficient greedy-penalty heuristic are, respectively, used to solve the two problems and we show that these perform significantly better than simple heuristic and random approaches.

Reinforcement learning-based group navigation approach for multiple autonomous robotic systems

In several complex applications, the use of multiple autonomous robotic systems (ARS) becomes necessary to achieve different tasks, such as foraging and transport of heavy and large objects, with less cost and more efficiency. They have to achieve a high level of flexibility, adaptability and efficiency in real environments. In this paper, a reinforcement learning (RL)-based group navigation approach for multiple ARS is suggested. Indeed, the robots must have the ability to form geometric figures and navigate without collisions while maintaining the formation. Thus, each robot must learn how to take its place in the formation, and avoid obstacles and other ARS from its interaction with the environment. This approach must provide ARS with the capability to acquire the group navigation approach among several ARS from elementary behaviors by learning with trialand-error search. Then, simulation results display the ability of the suggested approach to provide ARS with capability to navigate in a group formation in dynamic environments. With its cooperative behavior, this approach makes ARS able to work together to successfully fulfill the desired task.

Heterogeneous waveband switching in wavelength division multiplexed networks based on autonomous clustering architecture [Invited

Feature Issue on Waveband Switching, Routing, and GroomingAdopting waveband switching (WBS) in backbone wavelength division multiplexed (WDM) networks is promising since it can reduce the network operational cost and the call blocking probability. However, upgrading the existing optical switching architecture requires time and money. Thus heterogeneous waveband switching (HeteroWBS) architecture would be desirable in such a system, where some nodes can support WBS functions and some cannot. We study the performance of HeteroWBS networks in terms of call blocking probability and cost savings under dynamically arriving traffic requests. We first investigate the effects of optical component developments on waveband switching in WDM networks. Various connection managements are then listed and analyzed. Next, to assist in the designing of efficient WBS algorithms, an autonomous clustering-based HeteroWBS (AS-HeteroWBS) architecture is proposed. The AS-HeteroWBS architecture clusters the network into multiple autonomous systems (ASs). An AS may contain some specific nodes that provide WBS functions for all the nodes in the AS. Based on the architecture, three HeteroWBS algorithms are proposed, namely, the autonomous heterogeneous WBS algorithm (AS-WBS), the autonomous source-limited heterogeneous WBS algorithm (AS-S-WBS), and the shortest-path-based heterogeneous WBS algorithm (SH-WBS). Our simulation results show that the HeteroWBS algorithms can achieve optimal cost savings while maintaining the same network throughput compared with the algorithm without WBS.

SERVICE ORIENTED ORGANIZATION FOR CROSS-ENTERPRISE PROCESSES AND DISTRIBUTED TRANSACTIONS

The Information and Communication Technologies (ICT) are rapidly growing areas that are gaining substantial attention in the cross-enterprises collaborations. This paper proposes three-layer architecture to enact a common Business Process by means of Web Services. It particularly develops a distributed transactional management support in order to orchestrate loosely coupled services into cohesive units of work and guarantee consistent and reliable execution. Thus, the necessary definitions and algorithms that can consistently maintain shared data are provided offering potentially spanning multiple autonomous information systems and local workflows of the collaborative enterprises.

LOGUE: an architecture for task and behavior object transmission among multiple autonomous robots

This paper proposes a new communication and control architecture which improves the capability and the flexibility of multiple autonomous robot systems in performing a complicated task and coping with unpredictable situations. This system treats robot’s information as a Behavior Element Object (BEO) and a Task Object (TO) in terms of Object Oriented paradigm. Both BEO and TO can be serialized, so they can be communicated among the robots and behavior server system in the network. The action manager module, device module, and some checking mechanisms are also designed for executing new TO or BEO sent from other robots or a server system. A simulation and basic experiments are presented for a situation of robots’ relief for an emergency purpose.

A Space-Division Optical Wireless Communication System for Fully Distributed Multiple Autonomous Mobile Robots

This paper describes the realization of a space-division optical communication system specifically designed to perform local inter-robot communication in fully distributed multiple autonomous mobile robot systems. Requirements for autonomy and robustness of communication functions among moving robots are discussed. The communication system uses a set of modules, or transceivers, which is arranged in the circumference of the robot body. Each module comprises an IR detector/receiver and an IR transmitter. Each IR module detects the angle of incidence of infrared rays. Space-division communication networks can be created, because a robot can commumcate with more than one robot through different modules at the same time. Hardware realization and performance measurements are illustrated to reveal the effectiveness of the developed system.

Distributed Task Processing By a Multiple Autonomous Robot System Using an Intelligent Data Carrier System

Abstract This paper presents a new device called intelligent data carrier (IDC) for local information management. This device is useful for multiple autonomous robot systems which operate in a dynamically changing environment. In this paper, an IDC system which consists of IDCs attached to objects or environment and reader/writers mounted on autonomous mobile robots is introduced, and various IDC applications are proposed. As an example of the applications, a method for distributed task processing using the IDC system is mentioned, and the applicability of the system is verified through numerical simulations and experiments using actual robots.

Schema integration and transaction management for multidatabases

In this paper we propose a schema integration technique to integrate multiple autonomous database systems. We adopt the unified model, which is basically a relational model with object-oriented features, as the global model for integrating schemas of multiple databases in the relational, hierarchical, network, and object-oriented models. The features and the advantages of the unified model as the global model are discussed, then we describe the methodologies to integrate heterogeneous databases using this model and show how various types of conflicts are resolved. We also show how a global query on the integrated schema is handled in heterogeneous environment. We also present a transaction management scheme which uses semantic recovery techniques. Our scheme does not impose any restrictions on data items that transactions can read and write and does not violate local autonomy.

Concurrency control in multidatabase systems: A performance study

Abstract A multidatabase system (MDBS) is a federation of multiple autonomous local database systems (LDBSs). Over the years, it has been recognized that the most challenging issue of concurrency control in an MDBS has been a concern about how to resolve indirect conflicts and thereby to ensure global serializability (GSR), without sacrificing the local autonomy. Even though the global serializability issue is well understood and many concurrency control algorithms have been proposed, it is noticeable that the performance trade-offs of those algorithms are not yet understood. To address issues about the performance of concurrency control algorithms in an MDBS, we examine two MDBS concurrency control algorithms through simulation: optimistic ticket method (OTM) and global ticket method (GTM) that we have proposed. In OTM, the GSR is assured by way of accessing a local object (ticket), by which any indirect conflicts that may cause non-serializable execution are resolved. The global transaction manager (Global_TM) in GTM maintains a global variable (ticket), which is similar to timestamp, and the commit order of a GT is predefined by the order of assigned global ticket value. We examine the performance trade-offs of the two concurrency control methods (CCMs) with respect to ensuring GSR in particular. To ensure GSR, the (GTs) are expected to frequently restart in OTM and block in GTM. In this study, we also investigate the implications of time-out interval on the performance as we assume that the time-out approach is used as a global deadlock resolution method for both algorithms. Our experimental results showed that GTM outperforms OTM in cases that short time-out values are given. However, in case that the time-out value relatively becomes long, our results demonstrated that OTM outperforms GTM.

Planning systems in the next century (I)

This document is the first part of two articles that present a vision on planning systems in the next century. It is mostly concerned with the medium- and long-term planning levels, whereas the second paper is much more focused on the short-term planning level, e.g., shopfloor control. First, a brief overview is given of problems that exist in current planning concepts and planning systems. The general statement is that current planning concepts and systems are often too simple in their modelling of the real world. This is illustrated using the example of Material Requirements Planning (MRP). The next section describes five ‘vision statements’ that have been setup to present a vision on future planning systems. These statements describe a number of aspects of planning systems and should be seen as high-level directions in future developments. The most important thought presented here is that a transition will take place from one centralized planning environment into an environment that contains multiple autonomous planning systems, where planning systems are able to cooperate with other planning systems based on defined protocols. Furthermore, the role of the human planner will focus much more on control instead of execution. The last section describes a number of barriers that must be overcome to realize the presented vision.

Co-evolution of a multiple autonomous robot system and its working environment via intelligent local information storage

This paper proposes a new strategy of evolution and adaptation of a population of multiple autonomous mobile robots to make multi-robot systems more flexible and robust against unpredictable environmental conditions and human operator's capricious commands, and to overcome the limitation of biologically inspired techniques which need a certain degree of redundancy and diversity. The important idea of the strategy is to utilize the advantageous parallelism of the multi-robot system and immobile but portable devices (data carriers) for information storage and management. A device named IDC (Intelligent Data Carrier) is developed with a unique mushroom-like structure to be easily handled by a forklift mechanism which can be mounted on actual mobile robots. The handling method of the IDC unit, which should be essential to realization of the proposed strategy, is examined through the experiment using an omni-directional mobile robot, and the robot succeeded in placing the unit at an appropriate location. With the demonstrated handling technique, the robots can adapt and evolve as a population by accessing locally available information which is stored and processed in the IDC unit.

ロボット研究地図 複数自律ロボット系における漸進的戦略形成に関する研究

A method of distributed strategymaking in multiple autonomous system is presented in this paper. Every robot in the system has several tactics to be selected, and set of probabilities to select tactics are called “strategy”. The algorithm to make strategy in this paper is iteration of four parts as follows: (1) select and try a certain tactic by means of the strategy, (2) get payoff value for applied tactic from environment, (3) revise the estimated payoff value of tactics, (4) revise the strategy by using (3) . Effectiveness of the proposed method is verified by path selecting simulation of multiple mobile robots. Convergence to optimal solution in the proposed method is discussed by using pay-off matrices in game theory.

Serializability by commitment ordering

A new serializability concept, Commitment Ordering (CO), allows to effectively achieve global serializability across multiple autonomous Database Systems, that may use different (any) concurrency control mechanisms. CO generalizes the popular Strong-Strict Two Phase Locking (S-S2PL) concept.

Overview of multidatabase transaction management

A multidatabase system (MDBS) is a facility that allows users access to data located in multiple autonomous database management systems (DBMSs). In such a system, global transactions are executed under the control of the MDBS. Independently, local transactions are executed under the control of the local DBMSs. Each local DBMS integrated by the MDBS may employ a different transaction management scheme. In addition, each local DBMS has complete control over all transactions (global and local) executing at its site, including the ability to abort at any point any of the transactions executing at its site. Typically, no design or internal DBMS structure changes are allowed in order to accommodate the MDBS. Furthermore, the local DBMSs may not be aware of each other and, as a consequence, cannot coordinate their actions. Thus, traditional techniques for ensuring transaction atomicity and consistency in homogeneous distributed database systems may not be appropriate for an MDBS environment. The objective of this article is to provide a brief review of the most current work in the area of multidatabase transaction management. We first define the problem and argue that the multidatabase research will become increasingly important in the coming years. We then outline basic research issues in multidatabase transaction management and review recent results in the area. We conclude with a discussion of open problems and practical implications of this research.