Spelling suggestions: "subject:"inverse kinematic""
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Measuring the 13C(α,n) Reaction in Inverse Kinematics: A Preliminary InvestigationJones-Alberty, Yenuel S. January 2019 (has links)
No description available.
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Characterization of Postural Tremor in Essential Tremor Using a Seven-Degree-of-Freedom ModelGeiger, Daniel William 01 October 2014 (has links) (PDF)
Essential Tremor (ET), a condition characterized by postural and kinetic tremor in the upper limbs, is one of the most prevalent movement disorders. While pharmaceutical and surgical treatment options exist, they are not ideal. Assistive devices have the potential to provide relief to patients but are largely unexplored for ET. Furthermore, prior characterizations of essential tremor have focused on endpoint tremor and provide insufficient detail for designing such a device. We propose and demonstrate a novel method for characterizing essential tremor in the 7 proximal degrees of freedom (DOF) of the upper limb in various postures. In addition, we provide a preliminary characterization in a small number of patients with mild ET. We collected data from 10 patients with ET. Subjects were instrumented with four electromagnetic sensors that recorded orientation of upper limb segments. After a calibration, each subject positioned his/her upper limb in 16 different postures for 15 seconds each. This procedure was repeated 4 times for each subject, with each repetition being considered a run. Sensor data were converted to angular kinematic data for each DOF using inverse kinematics, a practice unique to this study. These data were then analyzed in the frequency domain to calculate the power associated with the tremor in each DOF and posture. More specifically, we computed the area of the periodogram over the 4-12 Hz frequency band typically associated with ET [narrow-band area (NBA)] and over the wider frequency band from 2 Hz to the Nyquist frequency [wide-band area (WBA)]. If significant peaks were found in the 4-12 Hz band, their frequency and amplitude were reported. Mixed-model ANOVA tests were used to investigate effects of DOF, posture, run, gravity, and patient characteristics on reported measures. NBA and WBA varied significantly between DOF, being lowest in the wrist, intermediate in the shoulder, and greatest in the elbow and forearm (pronation-supination). NBA and WBA also varied significantly with posture. Only 5% of observations had significant peaks, with 49% of peaks occurring in wrist flexion-extension and 39% occurring in wrist radial-ulnar deviation. Peak frequency was quite stereotyped (5.7 Hz ± 1.3Hz). Run had no significant effects, indicating that tremor measures were consistent over the duration of the experiment. Effects of gravity and demographic factors on measures were mixed and did not present a discernible pattern. This preliminary characterization suggests that tremor may be focused in a subset of upper limb DOF, being greatest (in terms of power) in elbow flexion-extension and forearm pronation-supination, and most concentrated (with peaks at a stereotyped frequency) in wrist flexion-extension and radial-ulnar deviation. Our method of 7 DOF characterization through inverse kinematics, in conjunction with future research (isolation studies, EMG, and finger DOF) may allow for optimal tremor suppression by an orthosis.
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Genetic Algorithm Based Trajectory Generation and Inverse Kinematics Calculation for Lower Limb Exoskeleton.Chamnikar, Ameya S. January 2017 (has links)
No description available.
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Modern Mechanical AutomataMcCrate, Mark P. January 2010 (has links)
No description available.
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Development Feasibility of a Universal Industrial Robot/Automation Equipment ControllerDick, Andrew B. 14 April 2006 (has links)
No description available.
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Robust and fuzzy logic approaches to the control of uncertain systems with applicationsZhou, Jun January 1992 (has links)
No description available.
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Design, Manufacturing, and Assembly of Modular Snake-Like Robotic Arm, Alongside Design and Implementation of System’s Digital-TwinBrown, Scott 01 December 2024 (has links) (PDF)
A unique modular snake-like robotic arm, also referred to as MA\RS – the Modular Arm \ Robotic System - was designed, manufactured, assembled, simulated, and programmed to create a modular robot which could move to a desired end position given the number of links, the position of the end link and the duration of motion. This robotic arm serves as the start of research into a modular space robotic system to be used in low-gravity environments. As such, this project focused on developing the initial design of the robot and its digital twin. The system’s modularity allows for changes to the robot’s workspace, which allow for the accomplishment of different tasks. The modular aspect of the robot required strong and lightweight links and used a bent sheet metal assembly to reduce mass and conserve strength. Each of the robot’s links used a custom-built PCB to power the system, send signals from the MCU (an ESP32-S2) to the motor, and communicate to the main controller using CAN Bus. Simulation of the robot was performed using a MATLAB script and GUI built in MATLAB’s App Designer, which calculated the system’s path planning and inverse kinematics. The GUI communicated with the robot (through serial) and controlled the robot’s motion as it was calibrated and moved from one location to another.
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Accuracy Enhancement of Robots using Artificial IntelligenceJohannes Evers, Till January 2024 (has links)
Robots have an underlying model to control their joints with the aim of reaching a specific pose. The accuracy of a robot is based on the underlying model and its parameters. The parameters of the underlying model of a robot are based on the ideal geometry and set by the manufacturer. If the parameters do not represent the physical robot accurately, the movements of the robot become inaccurate. Methods to optimize the parameters to represent the physical robot more accurately exist and result in an accuracy enhancement. Nevertheless, the underlying model of the manufacturer remains of analytical form and therefore has a limited complexity which hinders the model to represent arbitrary non-linearities and higher degree relations. To further enhance the accuracy of a robot by using a model with a higher complexity, this work investigates the use of a model of the inverse kinematics based on Artificial Intelligence (AI). The accuracy is investigated for a robot with an attached tool. In a first step, the development and initial evaluation of a suitable AI model is conducted in a simulated environment. Afterwards, the uncompensated accuracy of the robot with the tool is assessed and measurements are recorded. Using the measurements, an AI model based on the measurements of physical robot. The model is evaluated on the physical robot with a tool to quantify the achieved accuracy enhancement.
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Cinemática inversa para simulação de figuras articuladasOliveira, Luiz Ricardo Bertoldi de 19 July 2018 (has links)
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Previous issue date: 2018-07-19 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A simulação de figuras articuladas em computação gráfica que representam animais, pessoas ou robôs, normalmente, são compostas por uma cadeia de segmentos rígidos conectados por juntas dispostas de maneira hierárquica. Quando estas figuras possuem muitos segmentos, e precisam ser animadas por cinemática inversa, sua configuração de movimento pode apresentar múltiplas soluções ou soluções não-lineares além de singularidades de movimento. Este trabalho propõe uma nova topologia de juntas de hierarquia variável , generalista o suficiente para se aplicar a qualquer modelo articulado. Além disto, propõe um algoritmo de cinemática inversa que supra a não-linearidade dos modelos propostos até o momento. Um modelo como este, formaliza a animação de figuras articuladas que não precisam ter uma hierarquia de juntas rígida ou que possuam muitas juntas e segmentos. Para validação do modelo foi usada a Distância de Hausdorff para cálculo da similaridade do end-effector e um conjunto de pontos ideais com uma precisão 91.23%. O movimento foi suavizado em comparação a outros modelos por meio da minimização de 8,7% nos ângulos nas juntas. / The simulation of articulated figures in computer graphics that represents animals, people or robots is usually composed of a chain of rigid segments connected by joints arranged in a hierarchical way. When these figures have many segments and need to be animated by inverse kinematics, their motion configuration may present multiple solutions or nonlinear solutions and motion singularities. This work proposes a new topology of joints of a variable hierarchy, general enough to apply to any articulated model. In addition, it proposes an inverse kinematics algorithm to supply the non linearity of the models already proposed A model like this generalizes the animation of articulated figures because it do not need to have a rigid joints topology and works to figures with many joints and segments. Hausdorff Distance was used to calculate the end-effector similarity with an ideal set of points. The accuracy achieved is 91,23% of similarity. Motion of all joints is smoother when compared to other models by minimizing 8,7% of the angles.
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Roboto trajektorijos optimizavimas / Optimization of Robot TrajectoryLuneckas, Tomas 09 July 2009 (has links)
Baigiamajame magistro darbe nagrinėjamas šešiakojo roboto judėjimas. Pateikiami vienos kojos atvirkštinės kinematikos uždavinio sprendimai Denavito ir Hartenbergo bei geometriniu metodais. Analizuojamas vienos kojos trajektorijos sudarymo metodas ir pateikiams jos aprašymo būdas. Pateikiami galimi trajektorijų pavyzdžiai. Sudaroma trikojės roboto eisenos seka bei diagrama. Darbe pateikiamas roboto valdymo algoritmas ir valdymo programa, atsižvelgiant į apibrėžtus variklių valdymo kriterijus. Eksperimentiškai tiriamas roboto judėjimas lygiu paviršiumi taikant trikoję eiseną. Pagal rezultatus koreguojama eisena. Atliekami trajektorijos pakartojimo tikslumo bandymai. Įvertinus rezultatus pateikiamos baigiamojo darbo išvados ir pasiūlymai. / Hexapod robot locomotion is analyzed in this paper. Inverse kinematics solutions are proposed for one leg using Denavit-Hartenberg and geometric methods. Trajectory forming for one leg is analyzed and solution for delineating trajectory is introduced. Possible leg trajectory examples are presented. Tripod gait sequence and diagram is designed for robot. Work presents robot control algorithm and program according to motor control parameters. Robot locomotion over regular terrain using tripod gait is tested. Gait then is corrected according to test results. Tests are made for trajectory repeating accuracy. Conclusions and solutions are made according to results.
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