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We consider control systems with switchings in dynamics and control objective in the form of fixed terminal state. Two types of parameter deviations are discussed. In the first case, infinitesimal changes of system parameters are assumed, and in the second one, small changes in switching time are considered. Conditions for reachability of the control objective are formulated.
Here we describe the ongoing development of a unique computer model to simulate the upper-limb during sinusoidal tracking activity on the TheraDrive, a 1 degree of freedom (DOF) haptic stroke rehabilitation system. The model predicts longitudinal muscle forces while simulating Thera-Drive activity to better understand the physiological changes (e.g. muscle dynamics) that arise from stroke and subsequent...
A class of singularly perturbed stochastic differential equations (SDE) with linear drift and nonlinear diffusion terms is considered. We prove that, on a finite time interval, the trajectories of the slow variables can be well approximated by those of a system with reduced dimension as the singular perturbation parameter becomes small. In particular, we show that when this parameter becomes small...
Research centers performing biomedical research collide with the problem of the treatment of large amounts of data. Several scientific fields in biomedical adopt technologies that can analyze samples in a more accurate way thanks to the high granularity which the current equipment provide the results. The cloud computing technology allows to create scalable and flexible infrastructures and data management...
This paper contributes to the area of miniature legged robots by investigating how a recently introduced bio-inspired template for such robots can be used for navigation. The model is simple and intuitive, and capable of capturing the salient features of the horizontal-plane behavior of an eight-legged miniature robot. We validate that the model can be combined with readily available navigation techniques,...
This paper focus on resolving the trajectory tracking problem of two wheeled mobile robot. We begin by presenting the kinematic model of the robot which is the base of the control law than we present a PI controller and a model predictive controller to solve the problem of trajectory tracking. We performed a comparison between the performances of the classical PI controller and the predictive controller...
Developed a method for computer analysis of the microparticles motion parameters along trajectories, based on the proposed A. A. Vavilov principle consistent disclosure of structural, parametrical and signal uncertainty. Signal uncertainty is caused by instrumental and methodological errors in the localization of microparticles position in the trajectories resulting from image processing. The difference...
This paper proposes an algorithmic modeling and analysis method to study the dynamics of nonlinear biological systems. Motivated by the recent use of piecewise affine models in reachability analysis of continuous dynamical systems, we propose a multi-affine approximation method to study biological system models defined on hyperrectangle. We show that such approximation is useful for constructing system's...
The purpose of this work is the development of a hybrid guidance and control system for the trajectory tracking task of an underactuated Unmanned Surface Vehicle (USV). The novelty of the guidance system is based on neural dynamics and sliding mode integration. The biological neural dynamics model is designed to smooth the outputs of the sliding mode control, avoid sharp speed jumps and satisfy the...
Our research group has started a collaboration that analyzes data collected from biological snakes to provide insight on how to better program snake robots. Most data collected on biological snakes views the snakes from above and thus can only detect motion in the horizontal plane. However, both our robots and biological snakes are capable of generating motions both in the horizontal and vertical...
In this paper we are concerned with the control of unicycle-type wheeled mobile robots in presence of sliding effects. We elaborate two models for control purpose. In the first one, we take into account only the slipping effects. In the second model, we introduce only the skidding effects. For each model, we propose a robust control law against the sliding effects to solve a velocity tracking problem.
Animated movies are a popular way to communicate complex phenomena in cell biology to the broad audience. Animation artists apply sophisticated illustration techniques to communicate a story, while trying to maintain a realistic representation of a complex dynamic environment. Since such hand-crafted animations are time-consuming and cost-intensive to create, our goal is to formalize illustration...
We study a model for the exploitation of renewable stocks developed in [5]. In this particular control problem, the control law contains a measurable and an impulsive control component. We formulate Pontryagin's maximum principle for this kind of control problems (see [3]), proving first order necessary conditions of optimality. Manipulating the correspondent Lagrange multipliers we manage to define...
The diagram of interactions of a genetic regulatory network is represented in a natural and intuitive way by Boolean or other discrete models. Based largely on the structure of the network, rather than on more detailed kinetic properties of the system, discrete models are very useful to study the qualitative dynamics of the genetic network. Several methods for analysis of genetic networks combine...
This work proposes a globally convergent state estimation method for non-linear discrete-time systems, based on interval techniques. This approach is based on a Moving Horizon State Estimation method and a global optimisation technique by interval arithmetic. This state estimation algorithm provides a solution with global convergence properties, even for non-linear model. The performances of the method...
Discrete dynamical systems, and in particular nondeterministic Boolean automata, offer a convenient framework to analyse complex regulatory networks motivated by biological systems. In this paper, a method is proposed to analyse the dynamics of Boolean networks under the realistic context-sensitive asynchronous strategy. The main goal is to identify the operational interactions responsible for a given...
In this paper, a new adaptive controller is proposed for ultra-local model based control. The concept is based on the algebraic derivation techniques to estimate the two ultra-local model parameters. A comparison study with the control method of Fliess-Join which is based on some elementary differential algebra is developed. The robustness of the ultra-local model controllers with respect to noises,...
In this paper, we present a novel approach based on spatio-temporal marked point processes to detect and track moving objects in a batch of high resolution images. Batch processing techniques are applicable to and desirable for a large class of applications such as offline scene and video analysis, and provide better overall detection and data association accuracy than sequential methods. We develop...
S-system is a commonly used model for dynamic biological system. However, due to technical limitations, biological reaction networks are often only partially observable, which indicates that not all individuals incorporated in the model can be measured directly. Given a limited amount and quality of experimental data, it cannot be assured that the model structure and parameters can be estimated unambiguously...
In this study a modular control approach is used to provide target following ability for a patient eye suffering from downbeat nystagmus. To perform the task successfully, it is proposed to exploit the benefits of modular strategies. Therefore, vertical eye movements are decomposed to two distinct upward and downward motions, and the controller tries to dedicate each of them to one distinct module...
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