International Journal of Engineering Science Invention ISSN (Online):2319-6734.ISSN (Print):2319-6726 www.ijesi.org Volume 3 Issue 8I August 2014I PP.28-35 Stereo 3D Simulation of Rigid Body Inertia Ellipsoid for The Purpose of Unmanned Helicopter Autopilot Tuning 'Petar Getsov,2Svetoslav Zabunov,Maya Gaydarova .Space Research and Technology Institute at the Bulgarian Academy of Sciences.Bulgaria Sofia University,Bulgaria ABSTRACT:The current paper aims at presenting the capabilities and benefits of an online stereo 3D simulation for the purpose of unmanned helicopter autopilot tuning.The parameters of the helicopter airframe are important for tuning the gains in the autopilot.The airframe is modelled as a rigid body whose inertial properties are fully described by the inertia ellipsoid.The inertia ellipsoid is another form of presenting the moment of inertia tensor of rigid bodies but instead of using a numerical approach the described method implements 3D graphical visualization.The current paper focuses on the benefits from stereoscopic graphical 3D presentation of the inertia ellipsoid and how such a method helps designers and researchers analyse, synthesise and tune unmanned helicopter autopilot algorithms.The simulation,subject to the current material, may be observed at the following web address:http://ialms.net/sim/. KEYWORDS:Inertia ellipsoid in stereo 3D simulation.Rigid body inertia ellipsoid.Unmanned helicopter autopilot tuning. I.INTRODUCTION The current article shows a new method of presenting the inertia ellipsoid of rigid bodies and its properties using a visual online environment.A simulation that has unrestricted access on the Internet demonstrates the inertia tensor of various rigid bodies to researchers in universities and institutes around the world.The major features of the advised simulation are the stereo 3D environment,in which the inertia ellipsoid of various rigid bodies is demonstrated along with translations of the ellipsoid and its moment of inertia tensor to any point in the body reference frame.Along with the inertia ellipsoid,the principal axes of inertia are also displayed.The simulation prints the diagonalized translated moment of inertia tensor and the diagonalizing rotation matrix(Figure 1).The simulation,described in the current paper,may be observed on web address: http://ialms.net/sim/. CAORANLRUT0R01 a50 Coeynight osect Sham al mnterfarr rementw ■emmtnf例a0■01n Bodv mass101.100kgl 10 wih amf (v2)fm] a山■5 01 IntrmaEtchim cemfhiiret [1/s](etkrat-ft) a001 ody drath [u.85.1m] 5 Shes angular mementum I shem anulr velecity lody hegtt [nn5 Iml 24■ 0U087 ■m■4则 nestid eflprstid Cmnter of themen ef erta trr CY 050250四■ Srtn0 anguarvelcy o5ou时s 07应 097■125n0 3251行5 000251,7 040■.31国014 0a8■19n98 03739g■125 Figure 1.Translated moment of inertia tensor and inertia ellipsoid to the vertex of a rectangular parallelepiped- shaped homogeneous rigid body and 3D graphical visualization www.ijesi.org 28 |PageInternational Journal of Engineering Science Invention ISSN (Online): 2319 – 6734, ISSN (Print): 2319 – 6726 www.ijesi.org Volume 3 Issue 8 ǁ August 2014 ǁ PP.28-35 www.ijesi.org 28 | Page Stereo 3D Simulation of Rigid Body Inertia Ellipsoid for The Purpose of Unmanned Helicopter Autopilot Tuning 1 Petar Getsov, 2 Svetoslav Zabunov, 3Maya Gaydarova 1, 2 Space Research and Technology Institute at the Bulgarian Academy of Sciences, Bulgaria 3 Sofia University, Bulgaria ABSTRACT : The current paper aims at presenting the capabilities and benefits of an online stereo 3D simulation for the purpose of unmanned helicopter autopilot tuning. The parameters of the helicopter airframe are important for tuning the gains in the autopilot. The airframe is modelled as a rigid body whose inertial properties are fully described by the inertia ellipsoid. The inertia ellipsoid is another form of presenting the moment of inertia tensor of rigid bodies but instead of using a numerical approach the described method implements 3D graphical visualization. The current paper focuses on the benefits from stereoscopic graphical 3D presentation of the inertia ellipsoid and how such a method helps designers and researchers analyse, synthesise and tune unmanned helicopter autopilot algorithms. The simulation, subject to the current material, may be observed at the following web address: http://ialms.net/sim/. KEYWORDS: Inertia ellipsoid in stereo 3D simulation, Rigid body inertia ellipsoid, Unmanned helicopter autopilot tuning. I. INTRODUCTION The current article shows a new method of presenting the inertia ellipsoid of rigid bodies and its properties using a visual online environment. A simulation that has unrestricted access on the Internet demonstrates the inertia tensor of various rigid bodies to researchers in universities and institutes around the world. The major features of the advised simulation are the stereo 3D environment, in which the inertia ellipsoid of various rigid bodies is demonstrated along with translations of the ellipsoid and its moment of inertia tensor to any point in the body reference frame. Along with the inertia ellipsoid, the principal axes of inertia are also displayed. The simulation prints the diagonalized translated moment of inertia tensor and the diagonalizing rotation matrix (Figure 1). The simulation, described in the current paper, may be observed on web address: http://ialms.net/sim/. Figure 1. Translated moment of inertia tensor and inertia ellipsoid to the vertex of a rectangular parallelepiped￾shaped homogeneous rigid body and 3D graphical visualization