Monte Carlo localization (MCL) is a sample-based approach for representing probability density for the pose of a robot. MCL is widely used for mobile robots because of its robustness with respect to sensor noise. On the other hand, MCL can fail to estimate a pose of a robot if objects block measuring range of a laser sensor of the robot. Even though MCL fails to estimate the pose of the robot, MCL does not stop to estimate the pose because MCL does not have a self-diagnostic function. Therefore, detection of localization failure is essential for a mobile robot application. In the present paper, we propose a novel approach that detects the localization failure of MCL through logistic regression. The proposed approach has two advantages. First, it can detect whether position errors is larger than 0.15 m with a high accuracy. Second, the proposed method can detect localization failure by means of a statistically modeled equation. Moreover, as an example of an application using the probability of localization failure, we have proposed a hybrid localization scheme with MCL and laser odometry. The practical effectiveness of the proposed scheme is verified through experiments.

Various robots are being developed to support active human lifestyles throughout the world. In particular, robots that can support a comfortable lifestyle for elderly people are needed for the coming super-aging society in many countries. The authors have already proposed the Personal Robot (PR) shown in Fig. 1, which can follow a human being and carry their baggage; the PR user does not need to carry heavy bags, even after shopping. The PR, therefore, can encourage not only elderly people but also young people to walk outside. This means that the PR can support a life of wellness in the true sense. In conventional research, a control approach for the roll angle is proposed to ensure the stability margin for steady turning because in order to follow a human being, the PR must realize high traveling performance. In this paper, a method of reference generation for the roll angle and turning angular velocity is proposed to take into account the stability margin during the transient state using model predictive control. According to the proposed approach, the quickest turning motion can be realized by keeping the upper and lower boundary constraints for the zero moment point (ZMP). The effectiveness of the proposed approach is verified by experiment using the prototype PR.

As the world's communication needs increase, telecommunications providers are building larger and more complex networks to meet this demand. These evolving networks will often contain many technologies, and while most modern networks are still single-vendor, many companies are looking to diversify their networks. While on-the-wire interoperability is clearly defined by various standards bodies, the management of these heterogeneous networks remains mostly undefined. Most network management systems deployed today tend to be specific to a single technology domain (ATM, SDH), and are usually limited to the management of a single vendor's equipment. A service provider will use several unrelated and independent management systems to manage the various components of their network-this offers a less than optimal solution. This paper attempts to address this problem by describing an architecture for a network management system capable of managing such a heterogeneous network, while satisfying the critical requirements of scalability and cost-reduction. A prototype implementation of this architecture is also described, together with an example deployment of the system used to manage a small ATM network.

In this paper, we propose a new teaching system, ROPSII, by which the user can teach a robot a task with a task-level language. ROPSII has three features. First, the operator can perform three-dimensional visual programming based on our object-oriented language. Due to the flexibility of the language, the operator can easily apply the system to various tasks. Second, the operator can describe the failure recovery sequence separately from the main task sequence and automatically generate a detailed command sequence with a part sending a signal from the robot to the peripheral equipment and vice versa. These procedures are easy; the operator can perform them as if giving directions to a person to do so. Third, the operator can automatically develop a collision avoidance trajectory. It's generated by the original algorithm which efficiently operates as an off-line teaching system. We will introduce our recent approaches for establishing the new teaching system and discuss the applicability of the system in this paper.

We have developed a new robot arm with six joints that have torque sensors and geared reduction systems. This arm has compliance control ability without using a wrist force sensor. The techniques adopted here are the low friction and low gear ratio reduction system, nonlinear torque compensation, inertial torque feedforward compensation and joint torque control using joint torque sensor feedback. The experimental results show that this robot has high accuracy of trajectory in spite of large compliance, i.e. low position feedback gains. This robot can also take practical industrial tasks in high speed under uncertain positioning of works.

An object-oriented data model, MORE, in which the database specification facilities have been extended so that users can specify an object with various structures is presented. The structure of an object is changed by passing messages. MORE also provides a classtype, a user-defined type for classes with similar structures, in order to simplify the specification of class descriptions. The system generates operations useful for the classes by referring to a corresponding classtype. A prototype system and an example application are described.>

A framework for icon management which is quite object-oriented is proposed, and an iconic programming system named HI-VISUAL is presented on the basis of the framework. In the framework, icons represent real objects or concepts already established in a target application environment, whereas icons representing functions are not provided. A function is represented by a combination of two different icons. Each icon can take an active or a passive role against the other. The role sharing is determined dynamically, depending on the environment in which the icons are activated. Programming in HI-VISUAL and implementation issues of the system prototype, now in operation in a laboratory environment, are extensively discussed.>

A knowledge-based database assistant, KDA, is described that has a query-guide function, an SQL-like database query generator, and an interface for subset-English. KDA can be used to design the front end of an SQL database system or a computer-based SQL tutorial system. A method is discussed for transforming a semantic network representing a user's conceptual query into one providing the information required by the system to respond to a query. The query pattern is an expression in natural language representing the semantic structure of concepts. The user expresses queries by filling parentheses in the query patterns with appropriate words. The query-pattern instances thus obtained are then translated into SQL-like relational database queries. The translation is carried out by evaluating operations defined on a semantic network named G-Net which conveys knowledge about application fields, the database schema, and the syntax of SQL.>

User-interface facilities of a map information system HI-MAP that provide visual feedback to the user are presented. The facilities include semantic panning and zooming, overlaying of thematic maps, etc., and are available through an interactive menu system. HI-MAP retrieves map elements in a specified region on the basis of their relevance and their categorical classification. It has a data structure that includes logical and physical hierarchies for the management of semantic relationships and graphic map elements. The software for implementing these facilities is well modularized, and a variety of interfacing modes can be realized by simple communication between modules. The system contributes toward a reduction of the difficulties in obtaining what is really required from databases.>

The authors seek to establish a simple and flexible framework for internal representation of language-dependent information, and the behavior of language-oriented tools for user's operations. They present a system for generating language-oriented editors based on object-oriented concepts. Features of the target language are represented as classes and their relations. A program is represented as an abstract syntax tree. Each node in the tree belongs to a node class. For generating more advanced editors, probes, internal-classes, and gates are incorporated into the system. The system generates a flexible and easily extendable language-oriented editor from a target language description in a highly modularized fashion by using the description language which the system provides.>

The purpose of this study is to construct a system (an Extended Production System, for short, EPS) which selects a desirable strategy dynamically depending on its current state in the process of problem solving. In EPS, a special purpose production interpreter, which directs the system to change its strategies in cooperation with strategic rules, is provided on top of a Conventional Production System (for short, CPS). Furthermore, a set of tactic rules which is appropriate for the strategy is selected from a rulebase and used in order that CPS can restrict search space under the current strategy. This has made EPS capable of following up various problem solving requirements flexibly. A reduction of the number of comparisons between the tactic rules and Short Term Memory (STM) has been attained by declaration of a rule subset appropriate for the strategy in each strategic rule. These advantages have been examined through experiments in image data retrieval by examples.

The authors present an environment which involves a debugging tool to aid in the detection and removal at logic errors. The debugging tool is supported by a special architecture, named SPRING, which was originally developed for reliable execution of Ada or Pascal programs. Following an overview of the system backed up by SPRING, the details of SPRING architecture are described, and the implementation of high level debugging on the SPRING architecture is discussed. In conclusion, the trial could be seen as a step toward providing an advanced programming environment for the development of reliable software.

If an object to be observed is much larger than the field of vision, we should observe it part by part as in the case of eye fundus photographs or gastrocamera photographs. Subpictures obtained through partial observation should be assembled into a mosaic picture which shows the whole object. An arrangement graph which shows adjacency and spatial differences among subpictures is defined, and the properties of the arrangement graph are discussed. Furthermore, the condition of the arrangement graph for a mosaic picture to be defect-free, that for a subpicture to be redundant in a mosaic picture, and the way to find subpictures surrounding defect areas of a mosaic picture are shown. The discussion is based on a graph theory and a notion of space vectors.