Navigation of multiple mobile robots in a highly clutter terrains using adaptive neuro-fuzzy inference system

In recent years, the interest in research on robots has increased extensively; mainly due to avoid human to involve in hazardous task, automation of Industries, Defence, Medical and other household applications. Different kinds of robots and different techniques are used for different applications. In the current research proposes the Adaptive Neuro Fuzzy Inference System (ANFIS) Controller for navigation of single as well as multiple mobile robots in highly cluttered environment. In this research it has tried to design a control system which will be able decide its own path in all environmental conditions to reach the target efficiently. Some other requirement for the mobile robot is to perform behaviours like obstacle avoidance, target seeking, speed controlling, knowing the map of the unknown environments, sensing different objects and sensor-based navigation in robot’s environment.     

Adaptive group scheduling mechanism using mobile agents in peer-to-peer grid computing environment

Peer-to-peer grid computing is an attractive computing paradigm for high throughput applications. However, both volatility due to the autonomy of volunteers (i.e., resource providers) and the heterogeneous properties of volunteers are challenging problems in the scheduling procedure. Therefore, it is necessary to develop a scheduling mechanism that adapts to a dynamic peer-to-peer grid computing environment. In this paper, we propose a Mobile Agent based Adaptive Group Scheduling Mechanism (MAAGSM). The MAAGSM classifies and constructs volunteer groups to perform a scheduling mechanism according to the properties of volunteers such as volunteer autonomy failures, volunteer availability, and volunteering service time. In addition, the MAAGSM exploits a mobile agent technology to adaptively conduct various scheduling, fault tolerance, and replication algorithms suitable for each volunteer group. Furthermore, we demonstrate that the MAAGSM improves performance by evaluating the scheduling mechanism in Korea@Home. SungJin Choi is a Ph.D. student in the Department of Computer Science and Engineering at Korea University. His research interests include mobile agent, peer-to-peer computing, grid computing, and distributed systems. Mr. Choi received a M.S. in computer science from Korea University. He is a student member of the IEEE. MaengSoon Baik is a senior research member at the SAMSUNG SDS Research & Develop Center. His research interests include mobile agent, grid computing, server virtualization, storage virtualization, and utility computing. Dr. Baik received a Ph.D. in computer science from Korea University. JoonMin Gil is a professor in the Department of Computer Science Education at Catholic University of Daegu, Korea. His recent research interests include grid computing, distributed and parallel computing, Internet computing, P2P networks, and wireless networks. Dr. Gil received his Ph.D. in computer science from Korea University. He is a member of the IEEE and the IEICE. SoonYoung Jung is a professor in the Department of Computer Science Education at Korea University. His research interests include grid computing, web-based education systems, database systems, knowledge management systems, and mobile computing. Dr. Jung received his Ph.D. in computer science from Korea University. ChongSun Hwang is a professor in the Department of Computer Science and Engineering at Korea University. His research interests include distributed systems, distributed algorithms, and mobile computing. Dr. Hwang received a Ph.D. in statistics and computer science from the University of Georgia.     

Output-oriented power saving mode for mobile devices

Fast battery discharge is still the most nerve wracking issue for smartphone users. Though many energy saving methods have been studied, still users are not satisfied with their phone’s battery. Power management system provides low power mode when the phone is not in use for a long time. When the user is interacting with the phone, current system assumes the user is interactive and should keep the device in active mode. However, this is not true. After the user’s interaction, the device processes the request and displays the result on the smartphone’s output device. During this period, the user cannot see any meaningful information from the phone. In this paper, we propose a new low power mode where we put smartphone’s output device into low power mode while phone is preparing result for the user. We named this as o-sleep, an output-oriented power saving mode. While a device is processing a user’s request, output from the device may require preparation time. We consider the situation as the device’s output idle time and put the phone’s user interfaces into sleep mode while maintaining other subsystems in active state. To prove our concept, we have applied our technique onto various smartphone applications with varying operation environment. From the experiment, we found that the smartphone entered the o-sleep mode up to 58% of its total usage time in various test scenarios. Usability study supported feasibility of our proposed method.     

Wukong: A cloud-oriented file service for mobile Internet devices

Along with the rapid growth of heterogeneous cloud services and network technologies, an increasing number of mobile devices use cloud storage services to enlarge their capacity and share data in our daily lives. We commonly use cloud service client-side software in a straightforward fashion. However, when more devices and users participate in heterogeneous services, the difficulty of managing these services efficiently and conveniently increases. In this paper, we report a novel cloud-oriented file service, Wukong, which provides a user-friendly and highly available facilitative data access method for mobile devices in cloud settings. Wukong supports mobile applications, which may access local files only, transparently accessing cloud services with a relatively high performance. To the best of our knowledge, Wukong is the first file service that supports heterogeneous cloud services for mobile devices by using the innovative storage abstraction layer. We have implemented a prototype with several plugins and evaluated it in a systematic way. We find that this easily operable file service has a high usability and extensibility. It costs about 50 to 150 lines of code to implement a new backend service support plugin. Wukong achieves an acceptable throughput of 179.11 kB/s in an ADSL environment and 80.68 kB/s under a countryside EVDO 3G network with negligible overhead.     

Seed-based authentication for mobile clients across multiple devices

Authenticating users for mobile cloud apps has been a major security issue in recent years. Traditional passwords ensure the security of mobile applications, but it also requires extra effort from users to memorize complex passwords. Seed-based authentication can simplify the process of authentication for mobile users. In the seed-based authentication, images can be used as credentials for a mobile app. A seed is extracted from an image and used to generate one-time tokens for login. Compared to complex passwords, images are more friendly to mobile users. Previous work had been done in seed-based authentication which focused on providing authentication from a single device. It is common that a mobile user may have two or more mobile devices. Authenticating the same user on different devices is challenging due to several aspects, such as maintaining the same credential for multiple devices and distinguishing different users. In this article, we aimed at developing a solution to address these issues. We proposed multiple-device authentication algorithms to identify users. We adopted a one-time token paradigm to ensure the security of mobile applications. In addition, we tried to minimize the authentication latency for better performance. Our simulation showed that the proposed algorithms can improve the average latency of authentication for 40% at most, compared to single-device solutions.     

Image-based memory for robot navigation using properties of omnidirectional images

This paper proposes a new technique for vision-based robot navigation. The basic framework is to localise the robot by comparing images taken at its current location with reference images stored in its memory. In this work, the only sensor mounted on the robot is an omnidirectional camera. The Fourier components of the omnidirectional image provide a signature for the views acquired by the robot and can be used to simplify the solution to the robot navigation problem. The proposed system can calculate the robot position with variable accuracy (‘hierarchical localisation’) saving computational time when the robot does not need a precise localisation (e.g. when it is travelling through a clear space). In addition, the system is able to self-organise its visual memory of the environment. The self-organisation of visual memory is essential to realise a fully autonomous robot that is able to navigate in an unexplored environment. Experimental evidence of the robustness of this system is given in unmodified office environments.     

Selection and navigation of mobile sensor nodes using a sensor network

Hybrid sensor networks comprise of mobile and static sensor nodes set up for the purpose of collaboratively performing tasks like sensing a phenomenon or monitoring a region. In this paper, we present a novel approach for navigating a mobile sensor node (MSN) through such a hybrid sensor network. The static sensor nodes in the sensor network guide the MSN to the phenomenon. One or more MSNs are selected based on their proximity to the detected phenomenon. Navigation is accomplished using the concepts of credit based field setup and navigation force from static sensor nodes. Our approach does not require any prior maps of the environment, thus cutting down the cost of the overall system. The simulation results have verified the effectiveness of the proposed approach. In each of the simulation runs, the static sensor nodes were able to successfully guide the MSN towards the phenomenon.     

Autonomous mobile robots navigation using RBF neural compensator

This paper presents an approach to adaptive trajectory tracking of mobile robots which combines a feedback linearization based on a nominal model and a RBF-NN adaptive dynamic compensation. For a robot with uncertain dynamic parameters, two controllers are implemented separately: a kinematics controller and an inverse dynamics controller. The uncertainty in the nominal dynamics model is compensated by a neural adaptive feedback controller. The resulting adaptive controller is efficient and robust in the sense that it succeeds to achieve a good tracking performance with a small computational effort. The analysis of the RBF-NN approximation error on the control errors is included. Finally, the performance of the control system is verified through experiments.     

XMobile: A MB-UID environment for semi-automatic generation of adaptive applications for mobile devices

Ubiquitous Computing promises seamless access to information anytime, anywhere with different and heterogeneous devices. This kind of environment imposes new challenges to software development. For example, information and user interface should be adapted according to contextual characteristics such as user, environment, and access device. In case of device adaptation, the development challenge is related to the heterogeneity of the devices, which requires software engineers to create different versions for each type of device and every platform. This paper proposes a MB-UID (model-based user interface development) approach for semi-automatic generation of adaptive applications for mobile devices. An environment, called XMobile, offers a device-independent user interface framework and a code generation tool for providing fast development of multi-platform and adaptive applications according to device and platform features. A case study is also presented to illustrate how the environment can be used for constructing an application for heterogeneous devices with different network connectivity modes.     

CAD data visualization on mobile devices using sequential constrained Delaunay triangulation

3D graphic rendering in mobile application programs is becoming increasingly popular with rapid advances in mobile device technology. Current 3D graphic rendering engines for mobile devices do not provide triangulation capabilities for surfaces; therefore, mobile 3D graphic applications have been dealing only with pre-tessellated geometric data. Since triangulation is comparatively expensive in terms of computation, real-time tessellation cannot be easily implemented on mobile devices with limited resources. No research has yet been reported on real-time triangulation on mobile devices.In this paper, we propose a real-time triangulation algorithm for visualization on mobile devices based on sequential constrained Delaunay triangulation. We apply a compact data structure and a sequential triangulation process for visualization of CAD data on mobile devices. In order to achieve a high performance and compact implementation of the triangulation, the nature of the CAD data is fully considered in the computational process. This paper also presents a prototype implementation for a mobile 3D CAD viewer running on a handheld Personal Digital Assistant (PDA).     

Bandwidth reduction for remote navigation systems through view prediction and progressive transmission

Remote navigation systems, such as exploration of virtual 3D worlds or remote surgery, usually require higher bandwidth than the Internet connection commonly available at home. In this paper, we explore a set of techniques to reduce the bandwidth required by these applications. Our system consists of a client PC equipped with a graphics card, and a remote high-end server. The server hosts the remote environment and does the actual rendering of the scenes for several clients, and the new image is passed to them. This scheme is suitable when the data has a copyright or when its size may exceed the rendering capabilities of the client. The general scheme is the following: each time the position changes, the new view is predicted by both the client and the server and the difference information between the predicted view and the correct one is sent to the client. To reduce bandwidth we can improve the prediction method, and the transmission system. We present here two groups of techniques: First, a set of lossless methods which achieve reductions of up to a 9:1 ratio. These are a combination of a two-level forward warping, that takes advantage of spatial coherence, and a masking method, which allows to transmit only the information that really needs to be updated. Second, a set of lossy methods suitable for very low bandwidth environments which involve both progressive transmission and image reuse. They consider relevant parameters such as the number of pixels, the amount of information they provide, and their colour deviation in order to create a strategy for prioritizing the information transmission. This system allows to improve up to an additional 4:1 ratio. The quality of the generated images is very high, and often indistinguishable from the correct ones.     

MobGeoSen: facilitating personal geosensor data collection and visualization using mobile phones

Mobile sensing and mapping applications are becoming more prevalent because sensing hardware is becoming more portable and more affordable. However, most of the hardware uses small numbers of fixed sensors that report and share multiple sets of environmental data which raises privacy concerns. Instead, these systems can be decentralized and managed by individuals in their public and private spaces. This paper describes a robust system called MobGeoSens which enables individuals to monitor their local environment (e.g. pollution and temperature) and their private spaces (e.g. activities and health) by using mobile phones in their day to day life. The MobGeoSen is a combination of software components that facilitates the phone’s internal sensing devices (e.g. microphone and camera) and external wireless sensors (e.g. data loggers and GPS receivers) for data collection. It also adds a new dimension of spatial localization to the data collection process and provides the user with both textual and spatial cartographic displays. While collecting the data, individuals can interactively add annotations and photos which are automatically added and integrated in the visualization file/log. This makes it easy to visualize the data, photos and annotations on a spatial and temporal visualization tool. In addition, the paper will present ways in which mobile phones can be used as noise sensors using an on-device microphone. Finally, we present our experiences with school children using the above mentioned system to measure their exposure to environmental pollution.

室外自主移动机器人AMOR的导航技术

在非结构化环境,移动机器人行驶运动规划和自主导航是非常挑战性的问题。基于实时的动态栅格地图,提出了一个快速的而又实效的轨迹规划算法,实现机器人在室外环境的无碰撞运动导航。AMOR是自主研发的室外运动移动机器人,它在2007年欧洲C-ELROB大赛中赢得了野外自主侦察比赛的冠军。它装备了SICK的激光雷达,用来获取机器人运动前方的障碍物体信息,建立实时动态的环境地图。以A*框架为基础的改造算法,能够在众多的路径中快速地找到最佳的安全行驶路径,实现可靠的自主导航。所有的测试和比赛结果表明所提方案是可行的、有效的。     

CloudBot: Advanced mobile botnets using ubiquitous cloud technologies

The mobile botnet is a collection of compromised mobile devices that can remotely receive commands from the botmaster. Exploiting unique features of mobile networks and smartphones, mobile botnets pose a severe threat to mobile users, because smartphones have become an indispensable part of our daily lives and carried a lot of private information. With the development of cloud computing technologies, botmaster can utilize ubiquitous cloud technologies to construct robust and scalable C&C (command and control) channel for mobile botnet. In this paper, we propose Cloudbot, a novel mobile botnet, which outperforms existing mobile botnets in terms of robustness, controllability, scalability, and stealthiness. Although the basic idea of using cloud technologies seems straightforward, we explore the design space of exploiting such services and tackle several challenging issues to overcome the limitations of existing mobile botnets. We have implemented CloudBot by exploiting popular push services and cloud storage services, and evaluated it through extensive experiments. The results demonstrate not only the feasibility of CloudBot but also its advantages, such as stealthiness, robustness, and performance.     

Planners, navigators, and pragmatists: collaborative wayfinding using a single mobile phone

Shared use of mobile devices is increasingly prevalent in both research prototypes and in practice, however, little is known as to how to support best this interaction paradigm. In this paper, we present a study examining how pairs share a single mobile phone during a collaborative wayfinding activity. We provide a classification of strategies, role relationships and phone interactions employed to conduct the wayfinding activities in our study. While acknowledging that the factors determining how the phone was shared are nuanced and intertwined, our results illustrate how differences in the mobile application’s interface influenced shared use, wayfinding strategy and outcome.

Automatic form filling on mobile devices

Filling out forms for web based services on mobile devices is a very time consuming and frustrating task for users because of the limited text input capabilities. This is a critical bottleneck to obtaining a wide acceptance of such services, especially mobile commerce that often requires filling user data. We developed an architecture based on a local proxy on a mobile device and a lightweight algorithm for a comprehensive analysis of forms, which leads to the most probable user data to be filled in, driven by an initial rule set [Chie Noda, John Hamard, Enrico Rukzio, Alexander De Luca, Method and Apparatus for Automatic Form Filling on Mobile Devices, Patent. Publication number EP1777629, Publication date 2007-04-25]. We further discuss our implementation and the evaluation results for the algorithm as well as the usability of the prototype.     

An energy-efficient task scheduling for mobile devices based on cloud assistant

Mobile cloud computing is an emerging service model to extend the capability and the battery life of mobile devices. Mostly one network application can be decomposed into fine-grained tasks which consist of sequential tasks and parallel tasks. With the assistance of mobile cloud computing, some tasks could be offloaded to the cloud for speeding up executions and saving energy. However, the task offloading results in some additional cost during the communication between cloud and mobile devices. Therefore, this paper proposes an energy-efficient scheduling of tasks, in which the mobile device offloads appropriate tasks to the cloud via a Wi-Fi access point. The scheduling aims to minimize the energy consumption of mobile device for one application under the constraint of total completion time. This task scheduling problem is reconstructed into a constrained shortest path problem and the LARAC method is applied to get the approximate optimal solution. The proposed energy-efficient strategy decreases 81.93% of energy consumption and 25.70% of time at most, compared with the local strategy. Moreover, the applicability and performance of the proposed strategy are verified in different patterns of applications, where the time constraint, the workload ratio between communication and computation are various.     

An economics-based negotiation scheme among mobile devices in mobile grid

In this paper, we propose an economics-based distributed negotiation scheme among mobile devices in mobile grid. In our model, there are energy negotiation and transactions between buyer devices and seller devices. Dynamic allocation of energy resources in mobile grid is performed through online transactions within markets. Mobile devices can be sellers and buyers that use optimization algorithms to maximize predefined utility functions during their transactions. Seller device agents sell the underlying energy resources of the mobile device. Buyer device agent makes buying decisions within the budget constraints to acquire energy resources. An economics-based negotiation algorithm among mobile devices is proposed. The proposed algorithm decomposes mobile grid system optimization problem into a sequence of two sub-problems. In the simulation, the performance evaluation of economics-based negotiation algorithm is evaluated.     

Indoor navigation of a non-holonomic mobile robot using a visual memory

When navigating in an unknown environment for the first time, a natural behavior consists on memorizing some key views along the performed path, in order to use these references as checkpoints for a future navigation mission. The navigation framework for wheeled mobile robots presented in this paper is based on this assumption. During a human-guided learning step, the robot performs paths which are sampled and stored as a set of ordered key images, acquired by an embedded camera. The set of these obtained visual paths is topologically organized and provides a visual memory of the environment. Given an image of one of the visual paths as a target, the robot navigation mission is defined as a concatenation of visual path subsets, called visual route. When running autonomously, the robot is controlled by a visual servoing law adapted to its nonholonomic constraint. Based on the regulation of successive homographies, this control guides the robot along the reference visual route without explicitly planning any trajectory. The proposed framework has been designed for the entire class of central catadioptric cameras (including conventional cameras). It has been validated onto two architectures. In the first one, algorithms have been implemented onto a dedicated hardware and the robot is equipped with a standard perspective camera. In the second one, they have been implemented on a standard PC and an omnidirectional camera is considered.

Real-time data dissemination in mobile peer-to-peer networks

Mobile peer-to-peer networks have found many uses such as streaming of audio and video data. There are circumstances, such as emergency situations and disaster recovery, when real-time delivery is a fundamental requirement. The problem is challenging due to the limited network capacity, the variable transmission rates and the unpredictability with respect to the network conditions in the mobile peer-to-peer network.In this paper we address the problem of real-time data dissemination of multimedia streams in mobile peer-to-peer networks. Four routing algorithms are proposed based on a packet's deadline, priority or a combination of these metrics. They are simulated under different setups in a mobile peer-to-peer network with Bluetooth connectivity and nodes broadcasting audio and video streams using different priorities. We compare the performance of the algorithms using a number of metrics. Detailed experimental results are presented. Based on these results, propositions on the usage of the algorithms and the design of network requirements are presented.