Bellman equationA Bellman equation, named after Richard E. Bellman, is a necessary condition for optimality associated with the mathematical optimization method known as dynamic programming. It writes the "value" of a decision problem at a certain point in time in terms of the payoff from some initial choices and the "value" of the remaining decision problem that results from those initial choices. This breaks a dynamic optimization problem into a sequence of simpler subproblems, as Bellman's “principle of optimality" prescribes.
Filtre à réponse impulsionnelle finieEn traitement du signal, un filtre à réponse impulsionnelle finie ou filtre RIF (en anglais Finite Impulse Response filter ou FIR filter) est un filtre dont la réponse impulsionnelle est de durée finie. On parle le plus souvent de filtre RIF pour des filtres à temps discret. Un filtre numérique RIF est caractérisé par une réponse uniquement basée sur un nombre fini de valeurs du signal d'entrée. Par conséquent, quel que soit le filtre, sa réponse impulsionnelle sera stable et de durée finie, dépendante du nombre de coefficients du filtre.
Frequency synthesizerA frequency synthesizer is an electronic circuit that generates a range of frequencies from a single reference frequency. Frequency synthesizers are used in many modern devices such as radio receivers, televisions, mobile telephones, radiotelephones, walkie-talkies, CB radios, cable television converter boxes, satellite receivers, and GPS systems. A frequency synthesizer may use the techniques of frequency multiplication, frequency division, direct digital synthesis, frequency mixing, and phase-locked loops to generate its frequencies.
Transient responseIn electrical engineering and mechanical engineering, a transient response is the response of a system to a change from an equilibrium or a steady state. The transient response is not necessarily tied to abrupt events but to any event that affects the equilibrium of the system. The impulse response and step response are transient responses to a specific input (an impulse and a step, respectively). In electrical engineering specifically, the transient response is the circuit’s temporary response that will die out with time.
Frequency dividerA frequency divider, also called a clock divider or scaler or prescaler, is a circuit that takes an input signal of a frequency, , and generates an output signal of a frequency: where is an integer. Phase-locked loop frequency synthesizers make use of frequency dividers to generate a frequency that is a multiple of a reference frequency. Frequency dividers can be implemented for both analog and digital applications. Analog frequency dividers are less common and used only at very high frequencies.
ControllabilityControllability is an important property of a control system and plays a crucial role in many control problems, such as stabilization of unstable systems by feedback, or optimal control. Controllability and observability are dual aspects of the same problem. Roughly, the concept of controllability denotes the ability to move a system around in its entire configuration space using only certain admissible manipulations. The exact definition varies slightly within the framework or the type of models applied.
Sliding mode controlIn control systems, sliding mode control (SMC) is a nonlinear control method that alters the dynamics of a nonlinear system by applying a discontinuous control signal (or more rigorously, a set-valued control signal) that forces the system to "slide" along a cross-section of the system's normal behavior. The state-feedback control law is not a continuous function of time. Instead, it can switch from one continuous structure to another based on the current position in the state space.
Transformation de LaplaceEn mathématiques, la transformation de Laplace est une transformation intégrale qui à une fonction f — définie sur les réels positifs et à valeurs réelles — associe une nouvelle fonction F — définie sur les complexes et à valeurs complexes — dite transformée de Laplace de f. L'intérêt de la transformation de Laplace vient de la conjonction des deux faits suivants : De nombreuses opérations courantes sur la fonction originale f se traduisent par une opération algébrique sur la transformée F.
Separation principleIn control theory, a separation principle, more formally known as a principle of separation of estimation and control, states that under some assumptions the problem of designing an optimal feedback controller for a stochastic system can be solved by designing an optimal observer for the state of the system, which feeds into an optimal deterministic controller for the system. Thus the problem can be broken into two separate parts, which facilitates the design.
Commande prédictiveLa commande prédictive (ou compensation ou correction anticipatrice) est une technique de commande avancée de l’automatique. Elle a pour objectif de commander des systèmes industriels complexes. Le principe de cette technique est d'utiliser un modèle dynamique du processus à l'intérieur du contrôleur en temps réel afin d'anticiper le futur comportement du procédé. La commande prédictive fait partie des techniques de contrôle à modèle interne (IMC: Internal Model Controler).