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Analytical and graphical performance synthesis tools for multi-DOF mechanisms are developed in the companion of this two-part paper [1]. Various performance indices derived from the Jacobian matrix for analyzing performance characteristics of multi-DOF mechanisms were proposed. These performance indices are the local kinematic coupling index (inner product of the Jacobian column vectors), the local directional mobility index (ratio of the Jacobian's eigenvalues), and the local efficiency index (product of the Jacobian's eigenvalues). In this paper, effort is placed on the applicability of the proposed analytical and graphical synthesis tools used to aid the design of multi-DOF mechanisms. Two examples representing open and closed chain mechanisms will be used to illustrate the effectiveness and efficiency of the proposed method. First, a two-link planar robotic manipulator is used to apply the proposed method. Following that, a two DOF parallel drive road simulator illustrates applicability of the suggested tools. Through these examples, geometric parameters and joint range limits of the mechanism are optimized through the evaluation of performance indices, eigen-ellipse and intersection angle between trajectory contours.

Kinematic and kinetic performance are important issues in designing multi-degree-of-freedom mechanisms such as robotic manipulators. In the engineering design stage, it is especially important that the designer can grasp the characteristics of the mechanism. The aim of this study is to develop a means of representing the kinematic and kinetic performance of the mechanism in such a way that the performance characteristics are quantified analytically and visible graphically to the designer in their entirety at the conceptual design stage. Various performance indices are derived from the Jacobian matrix and its quadratic form. These performance indices are the local kinematic cross-coupling index (angle of intersection between column vectors of the Jacobian), the local directional mobility index (ratio of Jacobian's eigenvalues), and the local efficiency index (product of Jacobian's eigenvalues). Graphical images of these performance characteristics using eigen-ellipsoid and workspace trajectory contours are introduced. Critical performance points in mechanism workspace are identified and elaborated for design considerations. Based on the graphical representation of these performance characteristics, design rules for achieving different performance objectives can easily be implemented. This method is applicable to computer-aided design of a mechanism and predetermination of its kinematic and kinetic performance.

AIM: Few investigations of sleep structure in schizophrenia have concentrated on the relationship between objective and subjective sleep variables. The aim of this study was to assess objective sleep variables and subjective estimation of sleep duration and sleep quality. METHODS: Polysomnography was performed in 20 chronic patients with schizophrenia during three consecutive nights. After final awakenings subjects answered questions concerning subjective estimations of sleep duration, sleep latency, number of awakenings, and sleep depth. Pearson correlations between ranged subjective reports and objective sleep variables were performed. RESULTS: The results showed a high positive correlation between objective sleep latency and its subjective estimation; a positive correlation between subjective estimation of sleep depth and percentage of slow wave sleep (SWS%); a positive correlation between eye movement (EM) density and subjective estimation of wakefulness during the night; and a negative correlation between EM density and dream reports. CONCLUSION: We concluded that objective sleep variables are related to subjective sleep estimation in schizophrenic patients. In these patients, EM activity in REM sleep is related to the subjective feeling of wakefulness. (Int J Psych Clin Pract 2000; 4:63-67). [ABSTRACT FROM AUTHOR]