KNOWLEDGE REPRESENTATION, REASONING AND DECLARATIVE PROBLEM SOLVING, by Chitta Baral, University Press, Cambridge, 2003, xiv+530 pp., ISBN 0-521-81802-8 (Hbk, £60.00).

This paper proposes an effective top-down design approach for the mechanical design for assembly of a four degree-offreedom revolute jointed robotic arm. The design process begins by specifying top-level design criteria and passing down these criteria from the top level of the manipulator’s structure to all of the subsequent components. With this proposed approach, the sequential design intents are captured, organized and implemented based on the entire system’s objectives, as opposed to the conventional design process which aims at individual components’ optimization. By considering the mechanical arm’s performance objectives, the design starts with modeling the integration of all the individual links constituting the manipulator. During the design process, modifications are made based on the integrated information of kinematics, dynamics, and structural analyses of the desired robot configurations as a whole. An optimum assembly design is then achieved with workable subdesigns of the manipulator components. As a result, the proposed approach for manipulator design yields substantially less number of iterations, automatic propagation of design changes, and great saving of design efforts. Thus, it is suitable and can be used as a guideline for design automation purposes of complex systems such as robotic arms.

The purpose of the present study is to assess the influence of auditory and haptic signals on the manipulation performance in a virtual reality-based hand rehabilitation system. A personal computer, a tracker, and a data glove were included in this system. Three-dimensional virtual environments were developed. Forty volunteers were recruited to participate in a pick-and-place procedure, with three levels of difficulty and four feedback modes. Task time and collision frequency were the parameters used to evaluate their manipulation performance. It can be concluded that the haptics is a significant signal for improving a subject's performance at the high difficulty level.

In this paper an algorithm for designing spatial parallel manipulator parameters for a given workspace has been presented. At the beginning, architecture has been chosen that describes a general parallel manipulator. The manipulator may possess any number of limbs, consisting of links connected by spherical, revolute or linear joints as well as actuators. The parameters, which will be determined, are the lengths of the links of kinematic chains, the coordinates of the fixing points of the chains to the platform and the base, and orientations of the revolute engines axes situated at the base. The workspace may be specified in the form of any shape in the space containing a set of points of known coordinates and the limits in which the geometrical parameters may vary. The algorithm does not determine the exact values of the parameters, but only their functions. It leads to the necessity for further research in order to optimise the solutions.

Quay cranes are particular transportation devices for which operation's safety and CRAMP parameters (Cost, Reliability, Availability, Maintainability, and Productivity) should be fulfilled with regard to a harbor maintenance strategy. The maintenance process is first considered within a holistic modeling framework in order to cope with the current practices of treating strategic, operational and engineering maintenance issues independently without taking into account their interactions within an entire Enterprise System. Proactive maintenance is then highlighted as a new model aiming to globally optimize the components operation parameters throughout three interacting prognosis, diagnosis and monitoring processes. Technical issues related to Intelligent Maintenance System are finally proposed in order to support proactive maintenance operations at the enterprise field level and applied to quay cranes in a particular site within the frame of the European Eureka ‘Robcrane' project.

Smart devices used in continuous system, benefit from the addition of microelectronics and software that runs inside the device to perform control and diagnostic functions. Very small components, such as inputs/outputs blocks and overload relays, are too small to integrate data processing for technical-economic reason. However, it's possible to develop embedded intelligence and control for the smallest factory floor devices. In the paper, a generic model of smart equipment with reconfiguration functions is proposed. The interest of this functional model is that it can be used for smart devices but it can also be developed in modules for the nearest possible of the inputs and outputs in manufacturing equipment. This solution is economic for a great number of applications because it allows one to realise modular design and to standardise part of system in order to re-use it.

This paper presents a method for synthesising the joint profiles for a planar five-link biped walking on flat ground. Both single support and double support phases are considered. The joint profiles have been determined based on constraint equations cast in terms of step length, step period, maximum step height and so on. A special constraint equation is developed to eliminate the destabilising effect of the impact (heel strike) occurring in the system. Other advantages of our joint profiles include system stability during the double support phase and repeatability of gait. The method of formulating compatible trajectories of the hip and swing limb is employed. We demonstrate the advantages of this method over the one of direct formulation of the joint profiles in that it not only significantly simplifies the problem by de-coupling the biped into three subsystems (a trunk and two lower limbs), but also allows the incorporation of certain constraints without drastically increasing the complexity of the constraint equations. The effectiveness of the proposed method is demonstrated using computer simulations. We believe that this research can provide a valuable tool for generating motion patterns of bipedal gait.

A method is presented for generating the path that significantly reduces residual vibration of the redundant, flexible robot manipulator in the presence of obstacles. The desired path is optimally designed so that the system completes the required move with minimum residual vibration, avoiding obstacles. The dynamic model and optimal path are effectively formulated and computed by using a special moving coordinate, called VLCS, to represent the link flexibility. The path to be designed is developed by a combined Fourier series and polynomial function to satisfy both the convergence and boundary condition matching problems. The concept of correlation coefficients is used to select the minimum number of design variables. A planar three-link manipulator is used to evaluate this method. Results show that residual vibration can be drastically reduced by selecting an appropriate path, in the presence of obstacles.