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The nonlinear vibrations and chaotic motion of a carbon nanotube subjected to axial loads and rested on a Winkler and Pasternak foundation are studied. It is assumed that the carbon nanotube is simply-supported at both ends. The governing equation of motion for the nanotube and foundation system using the Euler-Bernoulli beam theory is developed. The Galerkin method is considered for the solution...
This paper presents a multi-joint lower limbs rehabilitation robot with three degrees of freedom. The robot includes seat, left mechanical leg, right mechanical leg and electric control box, and each mechanical leg includes the hip joint, knee joint and ankle joint which correspond to the hip joint, knee joint and ankle joint of human. The mechanical structure of the rehabilitation robot is described...
The article presents an approach for designing a feedforward compensation of a spatially distributed disturbance acting on a boundary controlled one dimensional heat conduction system. The disturbance affects the system behavior via a fixed spatial characteristic meaning that the spatial influence of the time dependent measured disturbance signal is a space dependent model parameter. The compensation...
The objective of this paper is to present an online trajectory tracking based on model predictive control for service robot. The key point of model predictive control (MPC) algorithm is to consider an on-line optimization problem so as to obtain the optimal control input sequence in a specific time period. The main characteristics of MPC are only the first element of the control sequence is implemented...
In this paper, we propose a novel unsupervised approach to enabling sparse action representations for the cross-view action recognition scenario. Superior to previous cross-view action recognition methods, neither target view label information nor correspondence annotations are required in this approach. Low-level dense trajectory action features are first coded according to their feature space localities...
Monitoring lower body motion, especially gait pattern, using low cost Inertial Measurement Units on a daily basis is becoming critically important for the diagnosis and rehabilitation of neurological diseases. The current state of the art algorithm is to double integrate motion acceleration and compensate cumulative errors by resetting velocity signals to zero at the stance-phase of each stride. However,...
In this paper we propose to drive an actuated orthosis using an adaptive controller based on a reference model. It is not necessary to know all the functions of the dynamic model. Needing only the global structure of the dynamic model, we use a specific adaptive controller to obtain good performance in terms of trajectory tracking both in position and in velocity. A Multi-Layer Perceptron Neural Network...
We propose a new heel-contact toe-off walking model based on the Linear Inverted Pendulum (LIP) model, which due to the linearity and the ease of manipulation of the equations, could be considered to be advantageous for a future online implementation for the generation of walking patterns. This new model is based on the so called functional rockers of the foot (heel, ankle and forefoot rockers), each...
Inspired by the aerial prowess of flying insects, we demonstrate that their robotic counterpart, an insect-scale flapping-wing robot, can mimic an aggressive maneuver seen in natural fliers — landing on a vertical wall. Such acrobatic movement differs from simple lateral maneuvers or hover, and therefore requires additional considerations in the control strategy. Magnetic force was chosen to enable...
An auto-landing guidance law on the basis of sliding mode control (SMC) is presented in this paper for landing an unpowered reusable launch vehicle (URLV) at the predetermined landing site. The guidance scheme, which takes the full nonlinear point-mass dynamics into account, is developed in three-dimensional space. For the sake of dealing with large initial condition errors, the guidance process is...
In order to improve the guidance precision of the ballistic missile interception, the target's trajectory prediction and the impact point prediction solution algorithm for interceptor's mid-course guidance are studied. Firstly, in allusion to the drawbacks of current ballistic missile's trajectory predication, the high precision ballistic missile prediction algorithms based on predictor-corrector...
In respect to descent trajectory optimization of stratospheric airships, thermal effects were considered. Basic thermal characteristics of stratospheric airships and energy equations about the film and the internal gas were introduced. Besides, the equations of motion for the airship were described in details. To minimum the flight time, a direct collocation method was adopted to convert the trajectory...
In order to improve smoothness of task trajectories, this paper describe algorithms to generate smooth-optimal trajectories based on the differential flatness of quadrotor. B-spline is used to parameterize the selected flat outputs, and the dynamic constraints or kinematical constraints on quadrotor are transferred to the control point constraints of B-spline. The trajectory generation is then considered...
Homotopic approach can greatly reduce the difficulty of solving optimal control problems. Although the technology of solving fuel-optimal problem by starting from the related energy-optimal one is widely used in constant-specific-impulse low-thrust trajectory optimization, it is no longer applicable for variable-specific-impulse problems. For the variable-specific-impulse low-thrust trajectory optimization,...
Space applications have raised the demand on autonomy, security and reliability for current reusable launch vehicle (RLV), which require guidance technology of vehicle must have strong robustness and adaptability. Based on preliminary research results, this paper outlines a method of developing an online predictive reentry trajectory planning and guidance law which use both angle-of-attack and angle-of-bank...
After generating reference trajectory in the process of reentry guidance for reusable launch vehicle, if the designed bank angle curve is too close to the constraint boundary, there is a great possibility for the obtained reference trajectory to exceed the reentry corridor boundary. This paper proposed a margin searching method, to reduce the likelihood of generating a reference trajectory which exceeds...
This document presents a mathematical and experimental analysis by the Lagrange equations and with a electrogoniometer, which allows us to obtain the trajectories realized by the knee, by the angular displacing between: hip, knee and ankle; with this and applying mathematical concepts, it is possible to determine the torque applied to the knee while getting up.
The effect of terminal ship-to-air missile intercepting maneuvering target at high speed is studied through the method of three-dimensional trajectory simulation based on vector operation. The three-dimensional vector equation of command acceleration is elicited according to TPN at first considering the seeker's noises and the rudder's overload limit. An algorithm of calculating miss distance caused...
In this paper, trajectory tracking control of hard rock Tunnel Boring Machine (TBM) is studied with a cascade control structure. The TBM thrust hydraulic system can adjust position and orientation during tunnel excavation. The model of thrust hydraulic system and the compound control technique of thrust hydraulic system are studied. In order to realize trajectory tracking control, the dynamic model...
A new guidance law with terminal trajectory angle constraint is designed for bank to turn flight vehicle, which aims at the fixed position ground target. The general form of guidance law with sight angle and sight angle velocity as feedback variables is presented, and the stability of it is proved via finite time convergent stability theory, which makes traditional optimal guidance as a specific example...
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