This note contains a description of an improved apparatus and procedure used for determining the moments of inertia of airplanes. The method, based on the pendulum theory, is similar to that previously used, but a recent investigation of its accuracy has resulted in the improvements described herein. The error, when using the new apparatus and procedure, has been found to be of the order of 1 percent. Sample data and calculation for an airplane are included in an appendix.
The application and results of the above method in ground oscillation tests are described. The various corrections to reduce the measured moment of inertia to the reference axis moment of inertia are presented. The results show that measurement of moment of inertia by this method is practicable, provided the knife edges and spring are arranged to minimize excitation of structural modes.
Because the chemical reaction rates needed to predict the dependence of degree of dissociation on distance behind the shock are not known, order-of-magnitude estimates of their values have been used in a numerical example, the purpose of which is to illustrate the use of reaction-rate equations to predict relaxation time and distance behind the shock front.
The National Advisory Committee for Aeronautics has adopted the practice of measuring the moments of inertia of all airplanes that become available through their use in flight research work. This paper, which is the first of a series presenting the results of such measurements, gives the momumental ellipsoids of ten army and naval biplanes and one commercial monoplane. The data wer obtained by the use of a pendulum method, previously described. The moments of inertia are expressed in coeffienct as well as in dimensional form, so that those for airplanes of widely spaced different weights and dimensions can be compared. The coefficients are also useful for estimating the moments of inertia of airplanes for which no measurements of inertia can be computed. To determine the accuracy with which the moments of inertia can be computed from design data, calculations were made of the monents of inertia for one of the above airplanes by summing up the moments of inertia of its constituent parts. It was found that computed values were in error 20, 10, and 5 percent for the X, Y, and Z axes, respectively.
This book contains the proceedings of the ROBOT 2013: FIRST IBERIAN ROBOTICS CONFERENCE and it can be said that included both state of the art and more practical presentations dealing with implementation problems, support technologies and future applications. A growing interest in Assistive Robotics, Agricultural Robotics, Field Robotics, Grasping and Dexterous Manipulation, Humanoid Robots, Intelligent Systems and Robotics, Marine Robotics, has been demonstrated by the very relevant number of contributions. Moreover, ROBOT2013 incorporates a special session on Legal and Ethical Aspects in Robotics that is becoming a topic of key relevance. This Conference was held in Madrid (28-29 November 2013), organized by the Sociedad Española para la Investigación y Desarrollo en Robótica (SEIDROB) and by the Centre for Automation and Robotics - CAR (Universidad Politécnica de Madrid (UPM) and Consejo Superior de Investigaciones Científicas (CSIC)), along with the co-operation of Grupo Temático de Robótica CEA-GTRob, "Sociedade Portuguesa de Robotica" (SPR), "Asociación Española de Promoción de la Investigación en Agentes Físicos" (RedAF), and partially supported by "Comunidad de Madrid under RoboCity2030 Programme".