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The purpose of this paper is to develop a computationally efficient and generally applicable measure for a pipe routing problem which decides the pipe paths and affects the pipe assembly feasibility. By imitating human thinking in pipe assembly planning, human's experience and intuition are quantified and applied in the pipe routing algorithm.

Human's imaginal thinking is simulated with procedures of knowledge representation, pattern recognition, and logical deduction; the algorithm transforms the physical obstacles and constraints into 3D pipe routing space and then into 2D planar projection, by using convex hull algorithm onto the projection, the shortest pipe route is found efficiently.

A novel pipe assembly planning algorithm by imitating human imaginal thinking is presented, which effectively solved the problem of conceiving the shortest pipe route in 3D space with obstacles and constraints.

The application of the algorithm in assembly planning of an aircraft engine pipe system is demonstrated. The algorithm can also be used in similar pipe planning problems such as industrial plant pipe planning and submarine pipe system design.

Human's imaginal thinking is introduced into pipe routing algorithm for the first time. By using graphics as the media to transfer the pipe routing information, human's experience and intuition in pipe assembly planning are quantified and computationally applicable.

The purpose of this paper is to propose a method to automatically generate individualized body size measurements from cloud point of a body scanner. It aims to propose a fast, reliable, and unambiguous method to obtain human body measurements for use in the garment industry.

Based on a previous study by the authors, geometric features on the scanned body are identified by computerized algorithms through mathematical definitions. Feature lines situated on the human body surface are created as polylines that pass through the body's features and three types of computer measurements (tape‐measurement, contour‐measurement, and linear‐measurement) are provided.

By dividing the body surface into rectangular patches using the feature lines as boundaries, the body can be reconstructed easily with a minimal amount of triangles while retaining the essential shape. The proposed measuring method applies to most manual measurements used in the garment industry. The authors evaluated the anthropometry variations of the same subject to explore the reliability of the proposed method. It was found that the precision of the method is well below the standard requirement of the traditional manual method.

In this research, subjects were scanned in standing pose; this pose minimizes regions obstructed by body parts and permits maximal acquisition of as many key landmarks. Since the features are identified by geometric analysis without the need for marker attachment, measurements of the required sitting position are impossible to obtain in the current study.

Resolution of meshing can be changed according to application requirements. Contrary to the traditional manual method, efficiency and precision are the advantages of the present method.

This paper aims to describe the development of a method of constructing three‐dimensional (3D) human body shapes that include a degree of ease for purpose of computerized pattern making.

The body shape could be made with ease allowance to an individual's unique body shape using sweep method and a convex method. And then generates tight skirt patterns for the reconstructed virtual body shape using a computerized pattern making system.

This paper obtains individual patterns using individually reconstructed 3D body shapes by computerized pattern development. In these patterns, complex curved lines such as waist lines and dart lines are created automatically using the developed method. The method is successfully used to make variations of a tight skirt to fit different size women. The author also used the method to make other skirts of various designs.

The method described in this paper is useful for making patterns and then garments, without the need for the garments to be later adjusted for the subject.

The purpose of the paper is to present an approach to detect and isolate the sensor failures, using a bank of extended Kalman filters (EKFs) using an innovative initialization of covariance matrix using system dynamics.

The EKF is developed for nonlinear flight dynamic estimation of a spacecraft and the effects of the sensor failures using a bank of Kalman filters in investigated. The approach is to develop fast convergence Kalman filter algorithm based on covariance matrix computation for rapid sensor fault detection. The proposed nonlinear filter has been tested and compared with the classical Kalman filter schemes via simulations performed on the model of a space vehicle; this simulation activity has shown the benefits of the novel approach.

In the simulations, the rotational dynamics of a spacecraft dynamic model are considered, and the sensor failures are detected and isolated.

A novel fast convergence Kalman filter for detection and isolation of faulty sensors applied to the three axis spacecraft attitude control problem is examined and an effective approach to isolate the faulty sensor measurements is proposed. Advantages of using innovative initialization of covariance matrix are presented in the paper. The proposed scheme enhances the improvement in estimation accuracy. The proposed method takes advantage of both the fast convergence capability and the robustness of numerical stability. Quaternion‐based initialization of the covariance matrix is not considered in this paper.

A new fast converging Kalman filter for sensor fault detection and isolation by innovative initialization of covariance matrix applied to a nonlinear spacecraft dynamic model is examined and an effective approach to isolate the measurements from failed sensors is proposed. An EKF has been developed for the nonlinear dynamic estimation of an orbiting spacecraft. The proposed methodology detects and decides if and where a sensor fault has occurred, isolates the faulty sensor, and outputs the corresponding healthy sensor measurement.

The problem of constructing the convex hull of a set of points and of curvilinear segments arises in many applications of geometric analysis. Although there has been much work on algorithms for the convex hull of a finite point set, there has been less on methods for dealing with circular line segments and the implementation issues. This paper describes a new method for finding the convex hull of a planar set of straight and circular line segments. It then concentrates on the implementation of the algorithm.

The application of robots to industrial problems often requires grasping and manipulation of the work piece. The robot is able to perform a task adequately only when it is assigned proper tooling and adequate methods of grasping and handling work pieces. The design of such a task requires an in‐depth knowledge of several interrelated subjects including: gripper design, force, position, stiffness and compliance control and grasp configurations. In this paper, we review the research finding on these subjects in order to present in a concise manner, which can be easily accessed by the designers of robot task, the information reported by the researchers, and identify based on the review, future research directions in these areas.

Reviews some of the good reasons for looking to real neural nets for guidance on ways of implementing effective parallel computation. Discusses existing artificial neural nets with particular attention to the extent to which they model real neural activity. Indicates some serious mismatches, but shows that there are also important correspondences. The successful applications are to image processing, pattern classification and automatic optimization, in various guises. Reviews important issues raised by extension to the symbolic problem solving of “intellectual” thought, the prime concern of classical AI. These illustrate the importance of recursion, and of a degree of continuity associated with any evolutionary process.

Handling feature interaction is an unsolved issue in feature recognition approach. This paper presents a method for recognizing the presence of feature interactions. First, based on the convex hull concept, a so‐called reference face is defined. Second, by adding the reference face into the attributes adjacency graph (AAG), a modified AAG is obtained. Two general feature types, namely depression and protrusion features, are identified by the reference face. The basic features such as slots, pockets and bosses are represented by the modified AAG. Any features that remain unrecognized by the modified AAG are regarded as interacting features. The types of reference faces and feature face are also classified. Based on the kind of face classification, the interacting features are finally recognized via a process of virtual face extension and volume addition.

Selection of an effective grasp of a complex object using a multifingered gripper is a challenging problem because of the many possible grasp positions that are typically available.

Given the geometrical description of the particular object feature to be grasped, all feasible grasps are performed in offline simulation using a geometrically accurate model of the desired gripper. The six‐dimensional convex hull for each grasp is computed and archived. This convex hull indicates the span of forces and torques that the grasp can resist. When a grasp is needed the force/torque due to the total object weight is estimated and the best grasp is selected. The selected grasp has minimum peak contact force consistent with equilibrium.

Experimental trials with several complex object show the method is capable of producing grasps which can support the object and resist external force/torque.

An accurate geometrical description of the feature to be grasped must be known in advance. This would typically be a cylindrical or prismatic portion of the object.

There are many environments in which a dexterous multifingered gripper must be used due to the variety of objects which must be grasped. The results indicate that effective grasps can be selected for complex objects from a database of simulated grasps.

The primary contribution of this paper is the use of a database of simulated grasps on simple graspable features to synthesize grasps on complex objects.

Volume mapping of large spherical particles to a Cartesian grid with smaller grid elements is typically required in application of simple immersed boundary conditions in coupled engineering simulations. However, there exists no unique analytical solution to computation of the volume of intersection between spheres and cubes. The purpose of this paper is to determine a suitable solution to this problem depending on the required level of accuracy.

In this work, existing numerical techniques for computing intersection volume are reviewed and compared in terms of accuracy and performance. In addition to this, a more efficient linear relationship is proposed and included in this comparison.

The authors find in this work that a simple linear relationship is both acceptably accurate and more computationally efficient than the contemporary techniques.

This simple linear approach may be applied to accurately compute solutions to fluid-particle systems with very large numbers of particles.