277 research outputs found
A Mobile Self-Leveling Landing Platform for Small-Scale UAVs
This thesis presents a semi-autonomous mobile self-leveling landing platform designed to launch, recover and re-launch VTOL UAVs without the need for human intervention. The landing platform is rugged, lightweight and inexpensive, making it ideal for civilian applications that require a base station from which a rotorcraft UAV can be launched and recovered on terrain that is normally unsuitable for UAV operations. This landing platform is capable of self-leveling on rough terrain and inclined slopes, and can autonomously operate in remote locations for extended periods of time using large onboard lithium batteries and wireless communication. This thesis discusses the unique design aspects of this landing platform that set it apart from similar systems, describes the prototype vehicle, and shows experimental results to demonstrate the system is fully functional and meets all the primary design requirement
Fuzzy logic control of a two degree of freedom parallel robot
Parallel robots differ greatly from their serial counterparts in terms of performance and mechanical ability. Serial robots are open chained mechanisms since each link is connected to an adjacent one and each joint is actuated, while parallel robots implement a closed chained structure. This type of structure consists of having the endpoint of each kinematic chain connected to one another, hence called the common point. There can be a multitude of kinematic chains, but each chain utilizes only one actuator located near the base of the system to perform the desired operation
Servo-sistema para perturbação controlada do equilÃbrio postural
Mestrado em Engenharia MecânicaO estudo do equilÃbrio postural é uma preocupação que se aplica igualmente
a seres humanos e robôs com pernas. Em relação a Humanos este problema
foca-se na deteção de patologias, avaliação da capacidade de manter
o equilÃbrio e recolher dados acerca da forma como o equilÃbrio é mantido.
Por outro lado, o estudo da postura de um robô tem como objetivo avaliar
e melhorar o seu controlo. Dada a necessidade de testar o equilÃbrio do
Projeto Humanóide da Universidade de Aveiro - PHUA, surgiu a ideia de
criar um sistema de distúrbio do equilÃbrio. A ideia é o sistema perturbar o
equilÃbrio utilizando forças de tração que poderão ser aplicadas em todas as
direções do plano horizontal. Como primeira abordagem, o conceito é testado
num pêndulo assistido por elásticos, com o objetivo de perceber qual
a melhor forma de controlar o sistema e encontrar possÃveis problemas para
o seu controlo. Numa primeira fase, é desenhado um controlador para criar
um estado de balanço em que as forças são iguais fazendo com que o pêndulo
fique imóvel. Numa segunda fase, depois de atingir o estado descrito
anteriormente, o pêndulo é brevemente puxado num sentido e são medidas
as forças e o ângulo do pêndulo para se analisarem os efeitos do estÃmulo.
Desta maneira, várias formas de aplicar estÃmulos são testadas assim como
diferentes estÃmulos. Percebeu-se que: é possÃvel aplicar estÃmulos repetÃveis
com este conceito; o facto de o sistema ser acoplado e não-linear causa dificuldades
para o controlo, sendo necessário adoptar novas estratégias. Esta
dissertação vai servir como suporte para o trabalho futuro, (que será construir
o sistema à escala do PHUA) oferecendo um conjunto de informações
e guias.Postural balance is a concern that applies to both humans and bipedal robots.
For Humans, this issue is focused on detecting some pathologies, evaluating
individual balance capability, and gather data on how equilibrium is maintained.
On the other hand the robot’s postural study aims to evaluate the
machine’s control and help tune it. Given the need to test the equilibrium
of University of Aveiro Humanoid Project - PHUA, the idea of creating a
balance disruption system came up. The idea is that the system disrupts
the balance using pull forces that can be applied in every direction of the
horizontal plane. As a first approach, the concept is tested on a pendulum
assisted by elastics, with the objective of understanding which is the best
way to control the system and find possible problems to its control. On an
initial phase, a controller is designed to create a state of balance where the
pull forces are equal making the pendulum stand still. On a second phase,
after achieving the state of balance described previously, the pendulum is
briefly pulled in a direction and tensile forces and the pendulum’s angle are
measured, with the purpose of analysing the effects of the stimulus. This
way, different manners of applying stimuli and different types of stimuli are
tested. It was realised that: it is possible to apply repeatable stimuli with
this concept; the fact that the system is coupled and non-linear brings obstacles
to its control, being necessary to adopt new control strategies. This
dissertation will serve as a support for future work, (which is building the
system at PHUA scale) offering a set of informations and guidelines
Technology 2001: The Second National Technology Transfer Conference and Exposition, volume 2
Proceedings of the workshop are presented. The mission of the conference was to transfer advanced technologies developed by the Federal government, its contractors, and other high-tech organizations to U.S. industries for their use in developing new or improved products and processes. Volume two presents papers on the following topics: materials science, robotics, test and measurement, advanced manufacturing, artificial intelligence, biotechnology, electronics, and software engineering
NASA Tech Briefs, October 1992
Topics covered include: Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication technology; Mathematics and Information Sciences; Life Sciences
NASA Tech Briefs, March 1995
This issue contains articles with a special focus on Computer-Aided design and engineering amd a research report on the Ames Research Center. Other subjects in this issue are: Electronic Components and Circuits, Electronic Systems, Physical Sciences, Materials, Computer Programs, Mechanics, Machinery, Manufacturing/Fabrication, Mathematics and Information Sciences and Life Science
NASA SBIR abstracts of 1990 phase 1 projects
The research objectives of the 280 projects placed under contract in the National Aeronautics and Space Administration (NASA) 1990 Small Business Innovation Research (SBIR) Phase 1 program are described. The basic document consists of edited, non-proprietary abstracts of the winning proposals submitted by small businesses in response to NASA's 1990 SBIR Phase 1 Program Solicitation. The abstracts are presented under the 15 technical topics within which Phase 1 proposals were solicited. Each project was assigned a sequential identifying number from 001 to 280, in order of its appearance in the body of the report. The document also includes Appendixes to provide additional information about the SBIR program and permit cross-reference in the 1990 Phase 1 projects by company name, location by state, principal investigator, NASA field center responsible for management of each project, and NASA contract number
Third International Symposium on Magnetic Suspension Technology
In order to examine the state of technology of all areas of magnetic suspension and to review recent developments in sensors, controls, superconducting magnet technology, and design/implementation practices, the Third International Symposium on Magnetic Suspension Technology was held at the Holiday Inn Capital Plaza in Tallahassee, Florida on 13-15 Dec. 1995. The symposium included 19 sessions in which a total of 55 papers were presented. The technical sessions covered the areas of bearings, superconductivity, vibration isolation, maglev, controls, space applications, general applications, bearing/actuator design, modeling, precision applications, electromagnetic launch and hypersonic maglev, applications of superconductivity, and sensors
Technology 2003: The Fourth National Technology Transfer Conference and Exposition, volume 2
Proceedings from symposia of the Technology 2003 Conference and Exposition, Dec. 7-9, 1993, Anaheim, CA, are presented. Volume 2 features papers on artificial intelligence, CAD&E, computer hardware, computer software, information management, photonics, robotics, test and measurement, video and imaging, and virtual reality/simulation
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