bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling and adaptive control of a flexible one-link manipulator
Authors: Chen Jian-Shiang , Menq Chia-Hsiang 
Published: March 2009

SUMMARYThe dynamics modeling and payload adaptability of a light-weight flexible one-link manipulator are studied. Using the FEM (Finite-Element Method) model of a flexible manipulator, a lower order Linear Quadratic Gaussian compensator can provide satisfactory performance without controller/observer spillover. Moreover, the payload can be separated from the beam model, therefore, it is expected that the identification algorithm should have better robustness than the other schemes. The simulation results have shown that the proposed payload-adaptation synthesizer, which synthesizes a payload identifier and a nominal regulator/estimator interpolator to obtain a near-optimal compensator, has good adaptability with varying payload. And the resulting synthesizer also provides a near-optimal damping for this sensor-actuator noncolocated system.
A direct approach to modeling an industrial robot from samples of input-output data
Authors: Karnik Ajit M. , Sinha Naresh K. 
Published: March 2009

SUMMARYThe increased demand on the performance and efficiency of industrial robots, has led to the design of sophisticated control systems. Such control systems require an accurate dynamic model of the system. A commonly used method of modeling an industrial robot, involves the description of a set of dynamic equations, relating actuator torques to loads and accelerations. These equations are generally quite complex and inconvenient for implementation on digital computers.Another method often used for identification, is the ‘indirect method’, in which the transfer function is obtained in two steps. The discrete time model is first derived from samples of the input and output measurements, which is then transformed to the continuous-time model. A limitation of this method is that it requires the excitation to be of the ‘persistently exciting’ type, thus precluding the application of simple inputs like the step signal.This paper describes a ‘direct’ method for identification of an ‘industrial robot’ from samples of input and output observations. Results of modeling an industrial robot and two simulations are presented. One of the simulations, and the industrial robot uses the step input as excitation. The other example was excited with an exponential input.
Expedient range enhanced 3-D robot colour vision
Authors: Jarvis R. A. 
Published: March 2009

SUMMARYRobotic vision is concerned with providing, primarily through image sensory data acquisition and analysis, the basis for planning robotic manipulator actions upon and within a restricted world of solid objects. Ideally, its function should correspond to the human visual system's capacity to guide hand/eye coordination or body/eye navigation tasks. Fundamental to the notion of functionality in a 3D space partially filled with solid objects, is the requirement to appreciate the depth dimension, from a particular viewpoint. Human vision abounds with depth cues derivable from imagery and many of these have been the subjects of study for robotic vision application. However, direct range recovery using time-of-flight methods (ultrasonic or light) has distinct advantages for robotics and it is easy to justify these alternative approaches despite (and maybe even because of) their independence from visual cues.This paper presents work in progress in the Computer Vision and Robotics Laboratory at The Australian National University towards implementing a robotic hand/eye coordination system with applicability in the scene domain of brightly coloured, simply shaped objects with relatively untextured surfaces in arbitrary 3 dimensional configurations. The advantages of using directly acquired range data (via a laser time-of-flight range scanner) in enhancing the scene segmentation phase of analysis is emphasised and fairly convincing results presented. Actual vision-driven manipulation has not yet been developed but plans towards this end are included.
Real-time cooperative interaction between structured-light and reflectance ranging for robot guidance
Authors: Kent Ernest W. , Wheatley Thomas , Nashman Marilyn 
Published: March 2009

SUMMARYWhen applied to rapidly moving objects with complex trajectories, the information-rate limitation imposed by video-camera frame rates impairs the effectiveness of structured-light techniques in real-time robot servoing. To improve the performance of such systems, the use of fast infra-red proximity detectors to augment visual guidance in the final phase of target acquisition was explored. It was found that this approach was limited by the necessity of employing a different range/intensity calibration curve for the proximity detectors for every object and for every angle of approach to complex objects. Consideration of the physics of the detector process suggested that a single log-linear parametric family could describe all such calibration curves, and this was confirmed by experiment. From this result, a technique was devised for cooperative interaction between modalities, in which the vision sense provided on-the-fly determination of calibration parameters for the proximity detectors, for every approach to a target, before passing control of the system to the other modality. This technique provided a three hundred percent increase in useful manipulator velocity, and improved performance during the transition of control from one modality to the other.
An efficient numerical approach for calculating the inverse kinematics for robot manipulators
Authors: Lenarčič Jadran 
Published: March 2009

SUMMARYThis paper compares three numerical methods for obtaining the joint trajectory of a robot manipulator, which causes movement along the desired Cartesian path. The first solves the kinematic equations, which are given in the Jacobian form, while the other two solve the nonlinear kinematic equations directly by using an iterative computational procedure based on the conjugate gradient technique. The computational efficiency of the proposed methods is estimated in terms of the execution time on a VAX 11/750 minicomputer. It is shown that by using the capacity of microcomputers, these methods could be well used in real-time computation.
A fuzzy model for learning in automata
Authors: Datta Ashoke Kumar 
Published: March 2009

SUMMARYA simple general model for learning, using a fuzzy set theoretic approach and fuzzy decision in an automaton which has nonfuzzy input/output, is proposed. The process has been modelled somewhat in the fashion of general biological systems, which may be viewed as a fuzzy decision process where learning consists in taking a tentative action and reinforcing the membership values on the basis of the results of that action. The model is tested on an automaton whose sole purpose is to follow the boundary on an object with which it makes contact during its movements. The automaton is simulated by a computer. it has standard 8–neighbourhood configuration with binary sense capability and three action capabilities. The automaton has been found to learn to take correct action in a large number of possible input situations within only a few thousand moves.
The three robot worlds — a view point (A Review of the different goals of robotics research)
Authors: Lee Mark H. 
Published: March 2009

SUMMARYThis paper deals with the motivation behind robotics. It surveys the different goals of robotics research and analyses the ways in which robotics could help in various domains. After discussing the task specifications, emphasis is placed on three research sub-cultures that form separate robot “worlds”, viz. the Model World, the Industrial World and the Human World. The paper concludes with a case study to illustrate the need to reduce rash predictions and stimulate better science.
Japan's robotics research for the next generation
Authors: Umetani Yoji , Yonemoto Kanji 
Published: March 2009

This paper discusses those study themes considered essential in responding to the expectations that are mostly likely to be generated by Japanese society in regard to robots in the coming one or two decades.First, for the purpose of understanding the current structure and status of research and development concerning robotics, statistical data based on the responses obtained from universities and national and public research institutes will be shown together with an illustration of the recent patent trends related to industrial robots. Then, an overview on the results of forecasts regarding robot technology by governmental bodies will be presented in an effort to predict the technological as well as social needs surrounding robots. Lastly, tasks of high contribution value for society requiring large-scale research and development systems will be both identified and clarified.
Vibration due to motion discontinuities in hydraulically actuated robots
Authors: Jones J. Rees 
Published: March 2009

SUMMARYVibrations in robot action, both in the arm control system and arm itself, and in the transported load, are a serious problem in the development of high speed systems. The paper discusses the typical causes of vibration resulting from the motion command in path controlled robots and those due to the failure of a system to meet the specified command through power and performance limitations. Experimental results illustrating such phenomena are presented. Methods of reducing the magnitude or occurrence of such vibrations through the improved design of motion commands, which take account of the vibratory nature of the system and load, are presented.
Robot vision implementation by high-speed image processor TOSPIX: Battery inspection
Authors: Kuno Yoshinori , Numagami Hideo , Ishikawa Minoru , Hoshino Hiroshi , Nakamura Yasushi , Kidode Masatsugu 
Published: March 2009

SUMMARYThis paper presents an intelligent robot vision system using TOSPIX which has been newly developed to realize frequently-used and time-consuming image processing functions at low-cost and high-speed. The vision system has been studied for use in observing surface information about electric parts (dry batteries), inspecting them and then placing good ones into a given box. Three major robot vision functions are implemented here: object recognition, inspection and position determination by binary and gray-scale image processing techniques. While binary image techniques are used in battery terminal inspection and box position determination gray-scale image processing functions are performed in a label pattern check on a battery surface, front or rear surface determination, and surface defect inspection.
The application of a flexible tooling system in a flexible manufacturing system
Authors: Carter Norman 
Published: March 2009

SUMMARYThe introduction of Flexible Manufacturing Systems, Cell Technology, and Automated Machining Techniques with the related reduction in manning levels has resulted in the development of tooling systems, tool management systems, and, independent tool magazines to service TURNING MACHINES where a high number of tools are required to cover one shift or unmanned operation.Actual cutting time (production time) represents a value between 5% and 20% of average machine utilisation time, and developments in cutting materials and geometries have largely exhausted rationalisation possibilities in this area.
VAL-II, a language for hierarchical control of a robot-based automated factory
Authors: Braganca C. A. J. , Sholl P. 
Published: March 2009

SUMMARYThe goal of manufacturing system development today is the integration of basic production elements to suit a variety of industrial and shop floor requirements. This may seem an awesome goal, but the authors suggest that careful assessment of requirement at each level and an appreciation of the true level of complexity needed at each level for control purposes, systematic integration will be possible as products become commercially available.Six levels of integration can be defined for robot-based
applications:
Level 1 - the single robot application level
Level 2 - the system with robots working in teams
Level 3 - the combination of different robot systems
Level 4 - the combination of feeding work automatically to islands of automation from fully automated warehouses.
Level 5 - the integration of planning and control functions
Level 6 - the integration of CAD based design functions.The approach to integration and the level to which it extends will to a large extent be determined by a company's objective, present computer capacity, general production capability and availability of appropriate flexible automation products and systems for use in a given industrial environment. This paper examines the global needs of hierarchical integration, the level of control needed and the implication of VAL-II to this end.
Contribution to a computer-aided choice of D.C. motors for manipulation robots
Authors: Potkonjak V. , Jakšić N. 
Published: March 2009

SUMMARYThis paper presents a method for a computer-aided choice of D.C. motors for manipulation robots. The method takes into account the complete dynamics of the manipulator mechanism. The discussion is concerned with the complexity of the actuator mathematical model. The necessary order of the model is found.
Synthesis of a minimum-time manipulator trajectories with geometric path constraints using time scaling
Authors: Ozaki H. , Mohri A. 
Published: March 2009

SUMMARYThe minimum-time and subminimum-time joint trajectories of manipulators with geometric path constraints are planned in consideration of physical constraints based on kinematics and dynamics. The idea of time scaling is introduced, i.e. a time scale factor k(t) and a set of joint trajectories, called reference trajectories, are used to describe all the sets of trajectories tracing the specified geometric path. The desirable factor k(t) which makes the travelling time as short as possible is obtained by two proposed methods: the first one is an iteratively improving method using B spline, and the second one is a directly minimizing method. These two methods are preferably applied to a geometric collision-free path of a manipulator.
Contribution to the dynamics and control of robots having elastic transmissions
Authors: Potkonjak V. 
Published: March 2009

SUMMARYThis paper discusses one problem of robot dynamics rarely mentioned in papers relevent to this field. It is the problem of torsional effects in torque transmissions (reducers, shafts, transmission chains, etc.). The problem is significant since oscillations can appear to be due to these effects. The complete dynamic model, which includes these effects, is derived and the possible simplifications considered. The position of feedback transducers is discussed since it appears as an important problem when it is intended to minimize the influence of these elastic vibrations. The discussion is based on eigenvalues and simulation results.
Prospects for introducing computer-integrated manufacturing in the USSR – a viewpoint
Authors: Baranson Jack 
Published: March 2009

SUMMARYIntensified automation related to computer integrated manufacturing (CIM) is viewed by Soviet planning authorities as a major means for increased productivity in Soviet industry. But efforts to increase automation are conditioned by the political–economic environment in which industrial production Systems are engineered and managed. The forces driving Soviet automation efforts are examined, and some tentative judgments are made on the proposed prospects for implementing changes aimed at enhancing the potential contribution of CIM to increased productivity in Soviet industry. The article is based on author's chapters in a forthcoming book, Soviet Automation: Perspectives and Prospects, edited by Jack Baranson (Mt. Airy, Md.: Lomond Publications, 1987).
Planning of manipulator joint trajectories by an iterative method
Authors: Yamamoto M. , Ozaki H. , Mohri A. 
Published: March 2009

SUMMARYManipulator joint trajectories are planned to make an arbitrary cost function as good as possible in consideration of physical constraints based on kinematics and dynamics of a manipulator system. An algorithm presented in this paper is an iteratively improving method using the local controllability of B spline. It can be also applied to the case that some points are specified and joint trajectories must pass through those points. This algorithm is applied to an example of trajectory planning of a manipulator with two links and two degrees of freedom.
Admissible trajectory determination for two cooperating robot arms
Authors: Lim Joonhong , Chyung Dong H. 
Published: March 2009

SUMMARYThe problem of finding an allowable object trajectory for a cooperating two-robot system is investigated. The purpose is to move an object from one point to another by firmly grasping it at two different points using two robotic hands. The major difficulty is caused by the fact that, unless the robots have true six degrees of freedom, the trajectories the object can follow are severely limited and, in general, are difficult to find. The method proposed in the paper is based on reformulating the problem as a nonlinear optimization problem with equality constraints in terms of the joint variables. The optimization problem is then solved numerically on a computer. The solution automatically gives the corresponding joint variable trajectories as well, thus eliminating the need for solving the inverse kinematic problem. The method has been successfully applied to a real experimental system.
On-line robot trajectory control in joint coordinates by means of imposed acceleration profiles
Authors: Aken Ir. L. Van , Brussel H. Van 
Published: March 2009

SUMMARYA method for trajectory control in the joint space is presented. An acceleration profile is proposed for each segment of the trajectory. After a twofold integration a position trajectory is obtained with advantageous characteristics. The position trajectory is completely dynamically balanced; it exhibits continuity up to the third derivative of the position. This way, minimum requirements are imposed on the actuators. The technique delivers predictable results since the trajectory deviates only slightly from a straight line connection between successive joint coordinates. Very limited computational effort is required.
Trajectory control of manipulators with time varying inertia links
Authors: Jumarie Guy 
Published: March 2009

SUMMARYOne way to increase the flexibility (or versatility) of manipulators is to use links with time varying inertia. One can then control both the joint torques and the inertias of the links therefore more pliancy in the practical utilisation of the arm. The paper deals with the Lagrangian formulation of the corresponding inertia control problem which can be considered either in open loop or in closed loop form. The general equations are derived and it is shown that one so obtains a set of uncoupled Ricatti differential equations which define the dynamics of the structural inertias. Problems related to stabilization and to structural parameter uncertainty are also considered.
Three-dimensional flexural-joint stiffness analysis of flexible manipulator arms
Authors: Meghdari A. , Shahinpoor M. 
Published: March 2009

SUMMARYThis paper presents a complete derivation of the combined flexural-joint stiffness matrix and the elastic deformation field of flexible manipulator arms treated in a three-dimensional fashion. The stiffness properties are derived directly from the differential equations used in the engineering beam theory. The expressions developed here can readily be used in the modeling, control and design of light weight flexible robot manipulators. A two-link arm is used to formulate these expressions and the results can be generalized to n–link manipulators. The stiffness matrix for a robotic link element in 3-D is of the order of 12 X 12, and for an n–link robotic arm the total elemental and system stiffness matrices will be of the order of the (12n X 12n) and 6(n + 1) X 6(n + 1), respectively.
Les apports respectifs des langages symboliques et de la cao en programmation des robots
Authors: Laugier C. 
Published: March 2009

SUMMARYA high-level robot programming language constitutes a general purpose interface for accessing the basic functional capabilities of a robot. On the other hand, CAD facilities give the possibility of using a subset of these capabilities in an easier fashion. In this paper, we show how a robot programming language and CAD facilities can be combined to obtain a robot programming system satisfying the need for generality, and allowing an easy connection with the basic robot programming functions. Such a connection is based on a “complete” simulator providing facilities for executing robot control programs on a graphic display, for describing manipulation tasks using interactive graphic tools, for simulating the physical world and its perception through sensors, and for displaying three-dimensional scenes as shaded pictures.
A new program package for the generation of efficient manipulator kinematic and dynamic equations in symbolic form
Authors: Kirćanski M. , Vukobratović M. , Kirćanski N. , Timčenko A. 
Published: March 2009

SUMMARYThis paper presents a new program package for the generation of efficient manipulator kinematic and dynamic equations in symbolic form.The basic algorithm belongs to the class of customized algorithms that reduce the computational burden by taking into account the specific characteristics of the manipulator to be modelled. The output of the package is high-level computer program code for evaluation of various kinematic and dynamic variables: the homogeneous transformation matrix between the hand and base coordinate frame, Jacobian matrices, driving torques and the elements of dynamic model matrices. The dynamic model is based on the recursive Newton-Euler equations. The application of recursive symbolic relations yields nearly minimal numerical complexity. Further improvement of computational efficiency is achieved by introducing different computational rates for the terms depending on joint angles, velocities and accelerations. A comparative study of numerical complexity for several typical industrial robots is presented.
Navigational path planning for a vision-based mobile robot
Authors: Arkin Ronald C. 
Published: March 2009

SUMMARYThe Autonomous Robot Architecture (AuRA) provides multi-level representation and planning capabilities. This paper addresses the task of navigational path-planning, which provides the robot with a path guaranteed to be free of collisions with any modeled obstacles. Knowledge supporting visual perception can also be embedded, facilitating the actual path traversal by the vehicle.A multi-level representation and architecture to support multi-sensor navigation (predominantly visual) are described. A hybrid vertex-graph free-space representation based upon the decomposition of free space into convex regions capable for use in both indoor and limited outdoor navigation is discussed. This “meadow map” is produced via the recursive decomposition of the initial bounding area of traversability and its associated modeled obstacles. Of particular interest is the ability to handle diverse terrain types (sidewalks, grass, gravel, etc.) “Transition zones” ease the passage of the robot from one terrain type to another.The navigational planner that utilizes the data available in the above representational scheme is described. An A* search algorithm incorporates appropriate cost functions for multi-terrain navigation. Consideration is given to just what constitutes an “optimal” path in this context.