Günümüzde yaşananları kayıt etmek neredeyse alışkanlık haline gelmiştir. Öyle ki insanlar için kaydın kendisinden çok kaydın kalitesi önem teşkil etmeye başlamıştır. Çözünürlüğün yanı sıra sarsıntısız bir çekim kaydın kalitesini... more
Günümüzde yaşananları kayıt etmek neredeyse alışkanlık haline gelmiştir. Öyle ki insanlar için kaydın kendisinden çok kaydın kalitesi önem teşkil etmeye başlamıştır. Çözünürlüğün yanı sıra sarsıntısız bir çekim kaydın kalitesini arttırmaktadır. Sarsıntısız bir kayıt için kameralar sabit kızaklara monte edilmektedir ama tabi ki bu kızakların belli bir hareket mesafesi vardır ve bu mesafe sınırsız değildir. Gimbal düzeneği ile kamera taşıyıcısı sabit kalmadan ve mesafe sınırı olmadan sarsıntıları en aza indirerek istenen resim kalitesinde görüntü çekimleri yapabilmektedir. Gimbal ile yürürken, bisiklet sürerken, koşarken, merdiven çıkarken-inerken sarsıntısız çekimler yapmak mümkün olmaktadır. Kameraya yerleştireceğimiz Internal Measuring Unit (IMU) sensör ile kameranın üç eksende (x-y-z) yaptığı hareketler algılanır ve kamera lensi hizasına yerleştirdiğimiz 3 adet fırçasız servo motora ters yönde hareket etmeleri için komut gönderilir. Bu şekilde kamera mümkün olduğu kadar sabit kalmış ve görüntülerin sarsıntısız bir şekilde kayıt edilmiş olması sağlanır.
Simple 3-D printable open source hardware designs have proven to be effective scientific instruments at low costs. Further development in this area is coupling open source electronics with 3-D printable mechanical components to make fully... more
Simple 3-D printable open source hardware designs have proven to be effective scientific instruments at low costs. Further development in this area is coupling open source electronics with 3-D printable mechanical components to make fully functional distributedly-manufactured mechatronic tools for science. One research area where such low-cost technology is needed is to characterize thin film anti-reflective coatings and transparent conducting oxides (TCOs) for the glass, mirror and solar photovoltaic industry whose transmission properties are angle dependent. To meet this research need a low-cost 3-D printable open source dual axis gimbal system is presented in this study. An Arduino based microcontroller is used to move the sample holder to the user specified angle where two stepper motors control the motion providing two degrees of freedom. The sample holder is made in such a way that samples can easily be mounted on it by two movable latches. The system was validated and characterized for: i) unidirectional accuracy, 1 Preprint: Nupur Bihari, Smruti Prasad Dash, Karankumar C. Dhankani, Joshua M. Pearce. 3-D printable open source dual axis gimbal system for optoelectronic measurements. Mechatronics 56, 175-187 (2018). DOI: https://doi.org/10.1016/j.mechatronics.2018.07.005 ii) repeatability, iii) backlash, iv) speed resolution and v) microstep size. Finally, the mechatronic system is tested for the intended application using a halogen light source and a spectrometer to measure transmission through glass TCO samples through a hemisphere. The system performed as expected has a unidirectional accuracy of 2.827°, repeatability of 1.585°, backlash error of 1.237°, maximum speed of 35.156° and a verifiable microstep size of 0.33°. Despite the highest mean squared errors, the open source gimbal system performed adequately while measuring transmission of radiation through glass with TCO coatings. This open source system also represents a 96% cost in savings as compared to the least expensive commercial variant. The high mean squared errors are offset by the cost of the system coupled with its open source nature that promotes further collaboration and hence, development.
Dual Gimbal Antenna Mechanism (DGAM) is a complex system used on satellites to achieve precise and accurate pointing of antenna using two axis steering. The design of the mechanism involves exhaustive Finite Element Analysis (FEA) so as... more
Dual Gimbal Antenna Mechanism (DGAM) is a complex system used on satellites to achieve precise and accurate pointing of antenna using two axis steering. The design of the mechanism involves exhaustive Finite Element Analysis (FEA) so as to evaluate response of the system under varied load conditions like launch accelerations, outer space thermal gradients etc. FEA software MSC PATRAN is used to realistically simulate different load conditions and evaluate system responses. The DGA mechanism has varied configurations that are derived from a base configuration in order to cater to different satellite mission requirements. In this regard, it is highly beneficial to have a tool that can automatically generate, based on user input, finite element models for various configurations of DGA mechanism under different load conditions. This helps in improved efficiency during FEA in terms of reduced modelling time and increased reliability. This paper aims at presenting a tool for automation of finite element modelling of Dual Gimbal Antenna mechanism for different spacecrafts. The method adopted in developing the tool is based on generation of a session file, executable on PATRAN, using scripting in PATRAN Command Language (PCL). The result of the work lies in enabling a novel approach towards finite element modelling of complex spacecraft mechanism components using script based automation that enables quicker FEA and faster parametric configuration studies.
In this paper, results from the analysis of the gimbal impact on the determination of the camera exterior orientation parameters of an Unmanned Aerial Vehicle (UAV) are presented and interpreted. Additionally, a new approach and... more
In this paper, results from the analysis of the gimbal impact on the determination of the camera exterior orientation parameters of an Unmanned Aerial Vehicle (UAV) are presented and interpreted. Additionally, a new approach and methodology for testing the influence of gimbals on the exterior orientation parameters of UAV acquired images is presented. The main motive of this study is to examine the possibility of obtaining better geometry and favorable spatial bundles of rays of images in UAV photogrammetric surveying. The subject is a 3-axis brushless gimbal based on a controller board (Storm32). Only two gimbal axes are taken into consideration: roll and pitch axes. Testing was done in a flight simulation, and in indoor and outdoor flight mode, to analyze the Inertial Measurement Unit (IMU) and photogrammetric data. Within these tests the change of the exterior orientation parameters without the use of a gimbal is determined, as well as the potential accuracy of the stabilization with the use of a gimbal. The results show that using a gimbal has huge potential. Significantly, smaller discrepancies between data are noticed when a gimbal is used in flight simulation mode, even four times smaller than in other test modes. In this test the potential accuracy of a low budget gimbal for application in real conditions is determined.
In this work, a control moment gyroscope (CMG) supported by active magnetic bearing (AMB) is considered with a gimbal angular movement. Gimbal angular movement in a CMG imposes extra load on magnetic bearings. A complete model of the CMG... more
In this work, a control moment gyroscope (CMG) supported by active magnetic bearing (AMB) is considered with a gimbal angular movement. Gimbal angular movement in a CMG imposes extra load on magnetic bearings. A complete model of the CMG system with flywheel, AMBs, and gimbal dynamics is derived for control design. Lyapunov based composite adaptive output feedback control is proposed for fast uncertainty compensation in the CMG system, and some simulation results are presented. For a gimbal angular velocity input, a flywheel rotor magnetic bearing system is simulated at constant rotational speed of the flywheel rotor.
badboy-badman-try to be a goodman Rabu, 18 Agustus 2010 Sejarah Rambut Gimbal. Lepas dari pandangan orang-orang umum, Dreadlock mempunyai filosofi tersendiri. Lepas dari perawatan rambut, secara alami rambut akan menyatu bersama membentuk... more
badboy-badman-try to be a goodman Rabu, 18 Agustus 2010 Sejarah Rambut Gimbal. Lepas dari pandangan orang-orang umum, Dreadlock mempunyai filosofi tersendiri. Lepas dari perawatan rambut, secara alami rambut akan menyatu bersama membentuk knot dan kusut atau disebut dreadlocks. Dreadlock merupakan fenomena universal. Spiritualist dari semua kepercayaan dengan latar belakangnya memasukan kedalam jalur ajarannya dengan tidak memperdulikan penampilan fisik dari individu penganut kepercayaan tersebut. Para pendatang terkadang tidak menyisir dan memotong rambutnya atau bahkan sebaliknya dengan menutup rambutnya. Disinilah bagaimana dreadlocks lahir. Orang Nazaret adalah masyarakat yang paling mengerti dalam mengembangkan dreadlocks. Di timur, Yogis, Gyanis dan Tapasvis dari semua sekte adalah pembawa dreadlocks yang terkenal.
In this paper are presented and interpreted the results of the analysis of the gimbal impact to the determination of the external orientation elements on the UAV. Gimbal presented in this paper is a 3-axis gimbal based on brushless... more
In this paper are presented and interpreted the results of the analysis of the gimbal impact to the determination of the external orientation elements on the UAV. Gimbal presented in this paper is a 3-axis gimbal based on brushless motors. The paper describes and explains the concept of the camera stabilizer on UAVs. For the purposes of this paper, the gimbal is improved by using the second inertial measurement unit (IMU). Two tests using one and two inertial measurement units were conducted on the stabilizer. Testing has determined multiple increase of precision of external orientation parameters of images obtained by improving the gimbal. Given that the testing is carried out in real dynamic environment, it was observed from statistical parameters more uniform dispersion with 5 times lower minimum and maximum values of the deviations on the improved stabilizer. This ultimately confirms greater reliability of external orientation parameters. The standard deviation of angular external orientation elements improved by the gimbal is 0.14º for φ or 0.10º for ω, which is in relation to the basic gimbal increase of about 5 times.
Experimental techniques are proposed to evaluate the dynamic properties of suspension-slider-air-bearing systems. The bump responses of the sliders and gimbal structures are measured. The modal parameters, such as frequencies, damping... more
Experimental techniques are proposed to evaluate the dynamic properties of suspension-slider-air-bearing systems. The bump responses of the sliders and gimbal structures are measured. The modal parameters, such as frequencies, damping ratios, and mode shapes of the systems are obtained by using the proposed procedure. The techniques are applied to investigate the dynamic properties of three systems. It is found that they have quite different properties, and the suspensions (gimbal) significantly affect the dynamic properties of the air bearings. Some gimbal designs generate additional modes in the frequency band of the air-bearing resonance, or introduce additional stiffness and/or inertia constraints to the slider-air bearings. The results also show that the proposed techniques are robust for experimentally evaluating the dynamic properties of the suspension-slider-air-bearing systems
