Compressed Transmission Mode: An Optimizing Decision Tool

In this paper we address the problem of host to host communication. In particular, we discuss the issue of efficient and adaptive transmission mechanisms over possible physical links. We develop a tool for making decisions regarding the flow of control sequences and data from and to a host. The issue of compression is discussed in details, a decision box and an optimizing tool for finding the appropriate thresholds for a decision are developed. Physical parameters like the data rate, bandwidth of the communication medium, distance between the hosts, band rate, levels of discretization, signal to noise ratio and propagation speed of the signal are taken into consideration while developing our decision system. Theoretical analysis is performed to develop mathematical models for the optimization algorithm. Simulation models are also developed for testing both the optimization and the decision tool box

Operator/System Communication : An Optimizing Decision Tool

Copyright 1990 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.In this paper we address the problem of operator/system communication. In particular, we discuss the issue of efficient and adaptive transmission mechanisms over possible physical links. We develop a tool for making decisions regarding the flow of control sequences and data from and to the operator. The issue of compression is discussed in details, a decision box and an optimizing tool for finding the appropriate thresholds for a decision are developed. Physical parameters like the data rate, bandwidth of the communication medium, distance between the operator and the system, baud rate, levels of discretization, signal to noise ratio and propagation speed of the signal are taken into consideration while developing our decision system. Theoretical analysis is performed to develop mathematical models for the optimization algorithm. Simulation models are also developed for testing both the optimization and the decision tool box.http://dx.doi.org/10.1117/12.2549

An Adaptive and Efficient System for Computing the 3-D Reachable Workspace

In this paper, we present an efficient system for computing the 3-D reachable workspace for redundant manipulators with joint limits. In our system, we have decomposed the 3-D reachable workspace problem into two major sub-problems: workspace point generation and surface computation. We describe different algorithms that are used to build these modules. Finally, we discuss the advantages offered by our system

An Adaptive and Efficient System for Computing the 3-D Reachable Workspace

In this paper, we present an efficient system for computing the 3-D reachable workspace for redundant manipulators with joint limits. In our system, we have decomposed the 3-D reachable workspace problem into two major sub-problems: workspace point generation and surface computation. We describe different algorithms that are used to build these modules. Finally, we discuss the advantages offered by our system

A Hybrid System For Computing Reachable Workspaces For Redundant Manipulators

Copyright 1991 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.An efficient computation of 3D workspaces for redundant manipulators is based on a "hybrid" algorithm between direct kinematics and screw theory. Direct kinematics enjoys low computational cost, but needs edge detection algorithms when workspace boundaries are needed. Screw theory has exponential computational cost per workspace point, but does not need edge detection. Screw theory allows computing workspaces points in prespecfic directions, while direct kinematics does not. Applications of the algorithm are discussed.http://dx.doi.org/10.1117/12.2538

3-D Perception and Recognition Under Uncertainty

Copyright 1991 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.This paper presents an efficient system for recovering the structural properties of objects with unknown 3-D shape. In this approach, we build adaptive maps for interpreting the object structure under uncertainty. We decompose the system into four major modules: sensing interface, knowledge base, map building and decision making, and the controller. The sensing interface acquires visual data and performs low and intermediate vision tasks for enhancing the acquired image sequences. The knowledge base contains different visual primitives and the possible exploratory actions. The map building and decision making module utilizes the different predicates that are stored in the knowledge base in order to resolve possible uncertainties. The decisions made in the map building and decision making module are then utilized by the controller module which resolves possible inconsistencies. The above process is repeated until the map stored in the third module contains a minimal number of three dimensional interpretations that cannot be reduced further. Motion primitives are used as sensing actions. Uncertainty models are developed for the sensor and for the image processing techniques being used. Further filtering and a rejection mechanism are then developed to discard unrealistic motion and structure estimates. This system is capable of recognizing the object structure efficiently and adaptively.http://dx.doi.org/10.1117/12.5881

A Computational Approach for Constructing the Reachable Workspaces for Redundant Manipulators

An efficient computation of 3D workspaces for redundant manipulators is based on a “hybrid” algorithm between direct kinematics and screw theory. Direct kinematics enjoys low computational cost, but needs edge detection algorithms when workspace boundaries are needed. Screw theory has exponential computational cost per workspace point, but does not need edge detection. Screw theory allows computing workspace points in prespecified directions, while direct kinematics does not. Applications of the algorithm are discussed

Three-dimensional workspace visualization for redundant articulated chains

This thesis deals with the problem of the 3D workspace visualization for anthropomorphic linkages, not only those with redundant degrees of freedom but also those with joint limits. Although the workspace problem has important applications in a variety of fields such as computer-aided design, ergonomic studies, and robotics, the problem\u27s computational complexity has never been analyzed. In addition, previous techniques suffer from one or more of the following drawbacks: high computational cost, computing 2D workspace cross sections, dealing with manipulators that have specialized geometry, or sensitivity to geometrical and numerical errors or approximations. We analyze the computational complexity of the problem and prove that it is NP-hard. Then, we decompose it into three major subproblems: workspace point generation, visualization, and criteria selection. We describe and compare different techniques for computing workspace points: direct kinematics based algorithms, nonlinear programming based algorithms, and force application based algorithms. Each class of these algorithms has advantages and disadvantages, and none of them supersedes the others in all applications. Instead of debating the merits of these algorithms, we integrate them into Hybrid algorithms that are capable of generating workspace points efficiently. The visualization module can be built by either surface-based or volume-based algorithms. Each class of these algorithms is more suitable than the others for certain applications. The criteria selection module interacts with the user and tailors the most appropriate techniques, from the workspace point generation and the visualization modules, based on the application requirements

Welding technology review : = Przegla̜d spawalnictwa

We do not had a pre-print version to post. Please use inter-library loan or obtain this article from ACM directly using the link below.In this paper, we discuss the problem of computing the reachable workspace for redundant manipulators. Algorithms that compute workspace boundary points by using screw theory are presented. These algorithms cannot distinguish holes and voids that are buried within the reachable workspace. We present an algorithm that utilizes inverse kinematics in order to detect the unreachable regions (holes and voids) within the reachable workspace.http://dl.acm.org/citation.cfm?doid=98894.9912