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A persistent question in multivariate neural signal processing is how best to characterize the statistical association between brain regions known as functional connectivity. Of the many metrics available for determining such association, the standard Pearson correlation coefficient (i.e., the zero-lag cross-correlation) remains widely used, particularly in neuroimaging. Generally, the cross-correlation...
Modeling the passive behavior of the knee in subjects with spasticity involves the applied external torques (e.g. gravitational torque), the intrinsic moments due to tissue properties, as well as active, neurally defined moments resulting from the hypersensitivity of reflexes introduced by disability. In order to provide estimates of the necessary intrinsic terms in the equation of motion, the push-pull...
A singing voice synthesizer has been developed for an entertainment tool. Using the synthesizer, operator can control pitch, loudness, and depth of vibrato for the vowel-like output sound by his arm motions. The phonetic quality of the sound is controlled by a wrist angle of the operator. Since unnecessary formant transition often occurs in this phoneme determination, the improved algorithm is proposed...
A novel method of doing co-ordinate transformation for LC/van der pol(vdp) oscillator is proposed. It allows vdp to be solved as a conservative system by applying Hamiltonian formulation using calculus of variation. The procedure is developed to calculate the constant of integration, a generalized concept of energy. Such constant of integration, which is different from energy, has implication on the...
In industry, the four-bar mechanism is popularly applied in the trajectory generation. Different types of trajectories are generated by the chosen of the ratio of links. However, the five-bar mechanism is more flexible to generate a specific path due to it has two degrees of freedom. The geared five-bar mechanism is then commonly used by reducing the degree of freedom of the mechanism into one by...
System-level design for hybrid systems is complex and error-prone. To ensure correctness, formal methods are usually considered, and have been successfully applied in practice. Refinement for discrete systems is well-known, while little work has been done for hybrid systems. In this paper, we first present an envelope semantics for hybrid systems, where control and physical devices are separately...
Simulation of retail space is a growing topic in the multi-agent systems community. Those systems vary depending on many issues, such as the type of store, or type of behaviour. The kind of issue that is wished to be simulated, or the type of data used to build the simulation, are other subjects of variations. Our ambition is to develop a simulator using a generic model, based on real data easy to...
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...
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