Eiji Arai

Knotting/Unknotting Manipulation of Deformable Linear Objects

Here, we propose a planning method for knotting/unknotting of deformable linear objects. First, we propose a topological description of the state of a linear object. Second, transitions between these states are defined by introducing four basic operations. Then, possible sequences of crossing state transitions, i.e. possible manipulation processes, can be generated once the initial and the objective states are given. Third, a method for determining grasping points and their directions of movement is proposed to realize derived manipulation processes. Our proposed method indicated that it is theoretically possible for any knotting manipulation of a linear object placed on a table to be realized by a one-handed robot with three translational DOF and one rotational DOF. Furthermore, criteria for evaluation of generated plans are introduced to reduce the candidates of manipulation plans. Fourth, a planning method for tying knots tightly is established because they fulfill their fixing function by tightening them. Finally, we report knotting/unknotting manipulation performed by a vision-guided system to demonstrate the usefulness of our approach.

Manipulation Planning for Knotting/Unknotting and Tightly Tying of Deformable Linear Objects

A planning method for knotting/unknotting and tightening manipulation of deformable linear objects is proposed. It is important for linear object manipulation in industrial/medical field to analyze knotting. Modeling of knotting/unknotting process is useful for design of knotting/unknotting system with different mechanism from human arms/hands and manipulation planning suitable for such system. Firstly, knotting/unknotting processes of a linear object is represented as a sequence of finite crossing state transitions. Secondly, grasping points and their moving direction to perform each state transition are defined. Then, possible qualitative manipulation plans can be generated on a computer system once the initial state and the objective state of a linear object are given. Thirdly, a planning method for tightly tying is proposed. Pulling parts for tightening knots can be determined by using this method. Finally, an experiment for tying an overhand knot by our developed system is shown.

Planning of one-handed knotting/raveling manipulation of linear objects

A planning method for linear object manipulation including knotting/unknotting by one hand is proposed. Firstly, topological states of a linear object are represented as finite permutations of crossing points. Secondly, transitions among topological states are defined. Then, we can generate possible sequences of state transitions, that is, possible manipulation processes from the initial state to a given objective state. Thirdly, a method for determination of grasping points and their moving direction is proposed in order to realize derived manipulation processes. Furthermore, a planning method for one-handed manipulation is proposed. Knotting by one hand is possible as any manipulation processes can be realized by iteration of one-handed operations. Finally, it is demonstrated that our developed system based on the above method can generate manipulation plans for raveling out of an overhand knot.

Knowledge and Skill Chains in Engineering and Manufacturing

Enhancing Knowledge and Skill Chains in Manufacturing and Engineering.- Enhancing Knowledge and Skill Chains in Manufacturing and Engineering.- Generic Infrastructure Requirements and Components.- Engineering Information Infrastructure for Product Lifecycle Managment.- Architecting an Ubiquitous & Model Driven Information Infrastructure.- Service Modeling for Service Engineering.- The Extended Products Paradigm, An Introduction.- Process Plant Information Integration in Three Dimensions.- Using Contexts in Managing Product Knowledge.- Object-Oriented Design Pattern Approach to Seamless Modeling, Simulation and Implementation of Distributed Control Systems.- An Interoperability Framework and Capability Profiling for Manufacturing Software.- IT-Supported Modeling, Analysis and Design of Supply Chains.- Multi-Strata Modeling in MCM and CLM for Collaborative Engineering.- Ontological Stratification in an Ecology of Infohabitants.- Logics of Becoming in Scheduling.- Communication in the Digital City and Artifact Lives.- Validating MEDIQUAL Constructs.- External Collaboration.- Distributed Engineering Environment for Inter-Enterprise Collaboration.- Agent Based Manufacturing Capability Assessment in the Extended Enterprise Using Step AP224 and XML.- Inter-Enterprise Planning of Manufacturing Systems Applying Simulation with IPR Protection.- A Study on Support System for Distributed Simulation System of Manufacturing Systems Using HLA.- Method and Tool for Design Process Navigation and Automatic Generation of Simulation Models for Manufacturing Systems.- Knowledge Management in BID Preparation for Global Engineering and Manufacturing Projects.- Supply Chain Engineering and the Use of a Supporting Knowledge Management Application.- A Planning Framework for the Deployment of Innovative Information and Communication Technologies in Procurement.- Supreme: Supply Chain Integration by Reconfigurable Modules.- Tools and Methods for Risk Management in Multi-Site Engineering Projects.- Development of an After-Sales Support Inter-Enterprise Collaboration System Using Information Technologies.- Collaborative Service in Global Manufacturing - a New Paradigm.- Remote Maintenance Support in Virtual Service Enterprises.- Factory Floor Infrastructure.- Intelligent Process Planning and Control Framework for the Internet.- Implementation of a Data Gathering System with Scalable Intelligent Control Architecture.- Creation of Feature Sets for Developing Integrated Process Planning System.- Proposal of Modification Strategy of NC Program in the Virtual Manufacturing Environment.- Dynamic Co-Operative Scheduling Based on HLA.- A Study on Data Handling Mechanism of a Distributed Virtual Factory.- A Study on Real-Time Scheduling Methods in Holonic Manufacturing Systems.- Sensitivity Analysis of Critical Path and Its Visualization in Job Shop Scheduling.- Enterprise Integration of Management and Automation in a Refinery.- Man-System Collaboration.- CAI System with Multi-Media Text Through Web Browser for NC Lathe Programming.- Web Based Operation Instruction System Using Wearable Computer.- Model-Based Description of Human Body Motions for Ergonomics Evaluation.- Model-Based Motion Analysis of Factory Workers Using Multi-Perspective Video Cameras.- Human Factor and its Identification in Manufacturing Prediction.

Manipulation planning for unraveling linear objects

A planning method for unraveling manipulation of deformable linear objects is proposed. In manipulation of a linear object, its raveling must be avoided. It takes much time to unravel it once it is raveled. Therefore, it is important to generate unraveling plans efficiently. First, a manipulation process of a linear object including its unraveling is represented as a sequence of its crossing state transitions. Then, possible manipulation processes can be generated once the initial and the objective crossing states are given. Second, qualitative actions to realize manipulation processes are determined. Third, a method for unraveling a linear object as far as possible when its crossing state can not be identified completely is proposed. Finally, an example of unraveling process generation is demonstrated

Dynamic Modeling of Linear Object Deformation Considering Contact with Obstacles

This paper describes the dynamic modeling of linear object deformation considering geometrical constraints and contact with obstacles. Deformable linear objects such as cables and strings are widely used in our daily life, some industries, and medical operations. Modeling, control, and manipulation of deformable linear objects are keys to many applications. We have formulated the static deformation of a linear object using the differential geometry coordinates. In this paper, we apply differential geometry coordinates to the dynamic modeling of linear objects. First, we formulate dynamic 2D deformation of an inextensible linear object based on a differential geometry coordinate system. Second, we consider dynamic deformation of the linear object when forces/moments and geometrical constraints are imposed on the object. Third, we model contact of a linear object with a circular obstacle. It can be applied to self-contact of the linear object. Finally, we show simulation results using the proposed modeling technique

Fishbone Model for Belt Object Deformation

A modeling method for representing belt object deformation is proposed. Deformation of belt objects such as film circuit boards or flexible circuit boards must be estimated for automatic manipulation and assembly. In this paper, we assume that deformation of an inextensible belt object can be described by the shape of its central axis in a longitudinal direction called “the spine line” and lines with zero curvature called “rib lines”. This model is referred to as a “fishbone model” in this paper. First, we describe deformation of a rectangular belt object using differential geometry. Next, we propose the fishbone model considering characteristics of a developable surface, i.e., a surface without expansion or contraction. Then, we formulate potential energy of the object and constraints imposed on it. Finally, we explain a procedure to compute the deformed shape of the object and verify the validity of our proposed method by comparing some computational results with experimental results.

Deformation path planning for manipulation of flexible circuit boards

A differential geometry based modeling of a belt object to represent its deformation path is proposed. Adequate deformation path of a belt object such as film circuit boards or flexible circuit boards must be generated for automatic manipulation and assembly. First, deformation of a belt object is described using the curvature of its central axis, torsion around the central axis and the curvature in the transverse direction. Second, a method to derive an adequate transition of the object shape from the initial state to the final state is proposed. It can be derived by minimizing the maximum of the local potential energy in the belt object during its manipulation. This is because locally excessive potential energy often leads to the excessive stress that makes fractures in the belt object. Finally, the validity of our proposed deformation path is verified by estimating the maximum local potential energy in a belt object.

Disassembly Support System for Used Products Considering Destruction of Their Parts

A disassembly support system which suggests efficient disassembly/destruction sequences is proposed. First, a precedence constraint graph for disassembly is applied to derivation of candidates for efficient destruction procedures. Using such graph, a product destruction of which is not efficient can be determined. Second, the access graph is introduced. It represents connection of empty spaces existing in/around a product. Using the access graph, possible removing sequences of parts can be derived. Next, evaluation of such sequences according to the number of required operations is proposed. Furthermore, parts grouping using the access graph is proposed to reduce the number of removing operations. After that, determination of destroying position is shown. Finally, the effectiveness of our proposed system is demonstrated with a case study. Using our proposed system, workers in recycling manufactures can dispose used products efficiently without knowledge about each product.

Deformation modeling of belt object with angles

A differential geometry based modeling to represent belt object deformation is proposed. Deformation of a belt object such as film circuit boards or flexible circuit boards must be estimated for automatic manipulation and assembly. First, the fishbone model to describe deformation of a rectangular belt object is explained. In this model, the object shape is represented by the curved “spine line” and straight “rib lines”. We can estimate deformation of the object by minimizing its potential energy under geometric constraints. Next, this model is modified to represent deformation in which the rib line at an endpoint does not coincide with the transverse edge. Moreover, the modified model is applied to a belt object with angles. The deformed shape of an angled object can be derived by separating it into rectangular parts and angled parts and by assuming that each angled part forms a part of a cylindrical surface. Finally, the validity of our proposed model is verified by comparing the computed shape of an L-shaped belt object with its measured shape.