This paper presents the control paradigm and embedded sensors for a mobile robot manipulator whereby the mobile platform and manipulator arm are designed as one entity to support both locomotion and manipulation simul...
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This technical note demonstrates the use of tetrahedral meshing for modelling a slanted semi-elliptical surface crack at a solid cylinder by finite element method (FEM). For a relatively small ratio of the crack depth...
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Industrial manipulators are deployed for a range of repetitive tasks in cluttered environments in which the robot must rapidly execute safe trajectories. While nominal robot models exist, true dynamic models of deploy...
Industrial manipulators are deployed for a range of repetitive tasks in cluttered environments in which the robot must rapidly execute safe trajectories. While nominal robot models exist, true dynamic models of deployed manipulators are typically unavailable. This paper addresses the problem of generating dynamically feasible, collision-free, time-optimal kinematic reference signals for redundant manipulators with unknown dynamics. A novel economic iterative learning control approach is developed to leverage repeated task executions to learn a time-optimal control signal for an uncertain robot model. Simulation results demonstrate the performance of the approach for a 7-DOF manipulator. An experimental analysis is performed to understand the impact of the initial reference trajectory on converged performance.
In a surveillance system the huge volume of recorded multidimensional data poses a great challenge to the user in performing meaningful analysis in efficient and coherent manner, especially in a human-vehicle or human...
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In this paper the amount and morphology of cortical and trabecular bone porosities were estimated using optical microscopy and micro-computed tomography technique. The hierarchical structure of porosity at different s...
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An optimization methodology aiming at energy and cost savings in frost-free refrigerators is advanced. A steady-state simulation model was devised and its predictions for energy consumption were compared with experime...
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作者:
MUELLER, MJMINOR, SDSAHRMANN, SASCHAAF, JASTRUBE, MJMJ Mueller
PhD PT is Assistant Professor Program in Physical Therapy Washington University School of Medicine 660 S Euclid Box 8083 St Louis MO 63110 (USA). SD Minor
PhD PT is Assistant Professor Program in Physical Therapy Washington University School of Medicine. SA Sahrmann
PhD PT FAPTA is Associate Professor Program in Physical Therapy Washington University School of Medicine. JA Schaaf
PhD is Visiting Research Associate and Lecturer Department of Mechanical and Aeronautical Engineering University of California Davis CA 95616. He was Hunter Assistant Professor of Mechanical Design Mechanical Engineering Washington University at the time of this study. MJ Strube
PhD is Professor of Psychology Washington University.
Background and *** with diabetes and peripheral neuropathy have a high incidence of injuries while walking. Biomechanical analysis of their walking may lead to treatments to reduce these injuries. The purpose of this ...
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Background and *** with diabetes and peripheral neuropathy have a high incidence of injuries while walking. Biomechanical analysis of their walking may lead to treatments to reduce these injuries. The purpose of this study was to compare (1) the gait characteristics, (2) the plantar-flexor peak torques, and (3) the ankle range of motion of subjects with diabetes mellitus (DM) and peripheral neuropathy with those of age-matched *** subjects, 10 with DM and a history of peripheral neuropathy (DM group) (mean age=58 years, SD=15, range=35–75) and 10 subjects without diabetes (NODM group) (mean age=57 years, SD=11, range=37–68), were *** following data were collected on all subjects: ankle joint mobility, plantar-flexor peak torque (ankle strength), kinematics of the trunk and lower extremity during normal walking, and ground reaction forces. Moments and power at the ankle, knee, and hip during walking were calculated using a two-dimensional link-segment *** DM group subjects showed less ankle mobility, ankle moment, ankle power, velocity, and stride length during walking than the NODM group subjects. A significant decrease in ankle strength and mobility appeared to be the primary factor contributing to the altered walking patterns of the DM *** and *** DM group subjects appeared to pull their legs forward using hip flexor muscles (hip strategy) rather than pushing the legs forward using plantar-flexor muscles (ankle strategy), as seen in the NODM group subjects. Implications for treatment are presented to attempt to reduce the number of injuries during walking in patients with DM and peripheral neuropathy.
In this paper, a radial basis function neural network-based (RBFNN) adaptive inverse controller for real-time position tracking control of a two phase hybrid stepper motor in microstep mode is presented. To ensure sys...
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In this paper, a radial basis function neural network-based (RBFNN) adaptive inverse controller for real-time position tracking control of a two phase hybrid stepper motor in microstep mode is presented. To ensure system's robustness and closed loop stability and to improve the performance of the controller, the RBF based adaptive inverse control is combined with a closed loop PID controller. Experimental results are provided for various types of trajectories, comparing the performance of the proposed controller to the same neuro-controller using feed forward back-propagation neural networks (FFBP) proposed previously by the authors. The results show the superior performance of RBFNN over FFBP neural networks. Also the comparison of neuro controllers with a conventional fixed gain stand-alone PID controller show the improvement of the controller performance from 80% up to 99.7% decrease in the mean squared error (MSE) for different trajectories. Trajectories were tracked with the maximum error of 0.02 up to 0.06 degrees. Also the robustness of the method is confirmed through experimental results comparing neuro-controllers and the conventional PID controller by varying the load's inertia and disturbance torques. For this purpose two methods were examined. First using the same neuro-controllers trained by the initial training data and in the second method, neuro-controllers were adapted by new training data according to the new working conditions.
Micro components of micro machines, such as mechanisms, gears, sensors and actuators which are almost invisible, have been made by recent advance of mechanical and electronic engineering. The production of micro machi...
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Micro components of micro machines, such as mechanisms, gears, sensors and actuators which are almost invisible, have been made by recent advance of mechanical and electronic engineering. The production of micro machines, however, requires new technologies for assembling micro parts into complete micro machines. Macro-micro teleoperation is one of the key technologies for constructing micro machines and will help human operators assemble micro parts with the skills they already have. First, we describe an experimental system for macro-micro teleoperation which we have developed. This system consists of a pair of prototype 2 DOF micro slave arms actuated by voice-coil motors to generate micro forces, and a pair of 2 DOF master arms actuated by the linear DD motors. Second, the basic characteristics of the system are introduced and the experimental results are presented.
This paper is concerned with the dynamic modeling and vibration measurement of a single or bundled power transmission line. The bundled power transmission line may consists of two or more electric lines, which are con...
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