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Actuator equation

For this purpose the inverse of the y-F mapping with A as a parameter must be calculated. The reconstructed transducer displacement is then obtained in a second step by fitting in the reconstructed force F into the actuator equation (6.56). The corresponding reconstruction filter equation is... [Pg.254]

If the electrical excitation and the mechanical load are limited to amplitude ranges where the dependence of the characteristic of the electrical transfer path and the actuator transfer path on the mechanical load as well as the dependence of the characteristic of the sensor transfer path and the mechanical transfer path on the electrical excitation can be neglected, then the vectorial operators in sensor equation (6.55) and in actuator equation (6.56) can be simplified to a hnear superposition of scalar operators ... [Pg.260]

If the mappings T in the sensor equation (6.75) and the actuator equation (6.76) are purely hysteretic they can be modeled by a Prandtl-Ishhnskii operator H, a modified Prandtl-Ishlinskii operator M or a Preisach hysteresis operator R depending on the degree of symmetry of the branching behaviour. The calculation of these hysteresis operators and the corresponding compensators from the measured output-input characteristic requires special computer-aided synthesis procedures which is based on system identification methods. Due to a lack of space, this article cannot further comment on these synthesis methods. However, a detailed description of both the synthesis method and the mathematical basics can be found in the literature [332,341,350-352,356]. [Pg.260]

The self-sensing solid-state actuator concept illustrated in Fig. 6.139a has the same structure as that in Fig. 6.139b but it is based on the linear system model according to (6.66) and (6.67). The compensation equation follows in this case from the actuator equation (6.67) and results in... [Pg.263]

Here D is the vector of the dielectric displacement (size 3x1, unit C/m ), S is the strain (size 6x1, dimension 1), E is a vector of the electric field strength (size 3x1, unit V/m) and T is a vector of the mechanical tension (size 6x1, unit N/m ). As the piezoelectric constants depend on the direction in space they are described as tensors e- is the permittivity constant also called dielectric permittivity at constant mechanical tension T (size 3x3, unit F/m) and 5 , is the elastic compliance matrix (size 6x6, unit m /N). The piezoelectric charge coefficient df " (size 6x3, unit C/N) defines the dielectric displacement per mechanical tension at constant electrical field and (size 3x6, unit m/V) defines the strain per eiectric fieid at constant mechanical tension [84], The first equation describes the direct piezo effect (sensor equation) and the second the inverse piezo effect (actuator equation). [Pg.345]

The design of smart materials and adaptive stmctures has required the development of constitutive equations that describe the temperature, stress, strain, and percentage of martensite volume transformation of a shape-memory alloy. These equations can be integrated with similar constitutive equations for composite materials to make possible the quantitative design of stmctures having embedded sensors and actuators for vibration control. The constitutive equations for one-dimensional systems as well as a three-dimensional representation have been developed (7). [Pg.465]

The strain in electric field-associated bending of a PVA-PAA gel is given by the equation g = 6DY/L2 (see Eq. 21). The strain depends on the electric power applied to the gel. Thus, the deflection increases as the thickness becomes small even if the electric power remains constant. The PVA-PAA gel rod of 1 mm diameter bends semicircularly within 1 s under both dc and ac excitation. An artificial fish with a PVA-PAA gel tail 0.7 mm thick has been designed, and it has been demonstrated that the fish swims forward at a velocity of 2 cm/sec as the gel flaps back and forth under sinusoidally varied electric fields (Fig. 13b). This prototype of a biomimetic actuator shows that translational motion may be produced using bending deformation [74],... [Pg.160]

The outline of this paper is as follows. First, a theoretical model of unsteady motions in a combustion chamber with feedback control is constructed. The formulation is based on a generalized wave equation which accommodates all influences of acoustic wave motions and combustion responses. Control actions are achieved by injecting secondary fuel into the chamber, with its instantaneous mass flow rate determined by a robust controller. Physically, the reaction of the injected fuel with the primary combustion flow produces a modulated distribution of external forcing to the oscillatory flowfield, and it can be modeled conveniently by an assembly of point actuators. After a procedure equivalent to the Galerkin method, the governing wave equation reduces to a system of ordinary differential equations with time-delayed inputs for the amplitude of each acoustic mode, serving as the basis for the controller design. [Pg.357]

The formulation of combustion dynamics can be constructed using the same approach as that employed in the previous work for state-feedback control with distributed actuators [1, 4]. In brief, the medium in the chamber is treated as a two-phase mixture. The gas phase contains inert species, reactants, and combustion products. The liquid phase is comprised of fuel and/or oxidizer droplets, and its unsteady behavior can be correctly modeled as a distribution of time-varying mass, momentum, and energy perturbations to the gas-phase flowfield. If the droplets are taken to be dispersed, the conservation equations for a two-phase mixture can be written in the following form, involving the mass-averaged properties of the flow ... [Pg.358]

An actuator fault can be generated by a malfunction of the cooling system, such as electric-power failures, pomp failures, valves failures, and leaking pipes. Without loss of generality, actuator faults may be modeled as an unknown additive term affecting the state equation in (6.5), due to unexpected variations of the input u with respect to its nominal value, i.e., the value computed by the reactor control system. [Pg.130]

Equation 76) <1993OM3019>, which react as ester and ketone enolate equivalents, respectively. The latter reaction requires the use of fluoride ion activation (tetrabutylammonium fluoride, TBAF) to actuate the addition. Central carbon alkylation is less common for allylpalladium reactions despite this, nucleophilic alkylation of TMEDA-stabilized 1,3-diphenylallyl palladium complexes proceeds selectively to the central carbon (Equation 77) <1995AGE100>. [Pg.602]

An additional advantage of this DO control system is the possibility of having a real-time estimation of the cells respiration rate. As can be observed in Equation 1, if C is constant, the term of the transfer kLa.(Cs-C) is equivalent to the consumption Q02 X. With the actuation value of the controller, the transfer rate can be calculated, and also the consumption at each moment (Kamen et al., 1996). There are several reports in the literature dealing with the use of respiration measurements to estimate cell concentration online, based on the assumption that, during the growth phase, each cell consumes a constant amount of oxygen (Yoon and Konstantinov, 1994 Ruffieux et al., 1998 Jorjani and Ozturk, 1999). [Pg.265]

The equations governing the mass transport of the electroactive species inside and outside the porous actuator with the corresponding initial and boundary condition are described and solved elsewhere [ 18] they result in a general solution for C (, /), representing the concentration profile of the species inside the porous actuator, Since the detection is carried out be the gate of the 1SFET, which is very closely located at the edge of the actuator (.r = 0). only the solution of C (0./) is of interest. The steady-state response for C (0./) is... [Pg.391]

This equation is the basis of both the electrovibration sind vibration potential listed in the electrokinetic phenomena of Table 9.10. In these cases, the root mean square (rms) voltage i=E L) is either measured as in the case of the colloid vibration potential or induced by an electrode and the rms pressure fluctuations (= AP) at the same fi quency are either induced by an ultrasonic actuator or measured with a pressure transducer, as in the case of electrovibration. [Pg.397]

FIGURE 2.7 Temperature dependence of NOj conversion to NO for the gas-phase reaction (Equation 2.22) on each of the NiO powders sintered at different temperatures. (Reprinted from Zhuiykov, S. and Miura, N., Development of zirconia-based potentiometric NOx sensors for automotive and energy industries in the early 21st century What are the prospects for sensors Sensors and Actuators B Chem. 121 (2007) 639-651, with permission from Elsevier Science.)... [Pg.62]

The actuation force or movement generated during redox cycling is directly related to the concomitant changes in mechanical properties. Using a simple linear elastic model of the small-strain mechanical properties of PPy, it has been shown that the actuation strain (eo) at a constant applied stress (a) is accurately predicted from Equation 3.3... [Pg.131]

It is usually more convenient to use the filter time (i.e., the time constant of the hrst-order hlter), Xf, to specify the amount of filtering applied to a sensor reading. In this manner, the time constant of the filter can be directly compared to the time constants of the actuator, process, and sensor to determine whether it affects the closed-loop dynamics. The filter factor, /, and the cycle time for applying the filter, Atf, can be used to calculate the filter time constant by the following equation ... [Pg.1221]

This analysis is based on an idealized model of the level of a tank and does not consider sensor or actuator dynamics and does not consider that horizontal tanks do not have a constant cross section. For these reasons, it is recommended that Equations (15.14) and (15.15) be used as initial estimates of the tuning parameters and that an on-line tuning factor, F be used to tune for the desired level control performance ... [Pg.1226]


See other pages where Actuator equation is mentioned: [Pg.166]    [Pg.250]    [Pg.252]    [Pg.253]    [Pg.262]    [Pg.166]    [Pg.250]    [Pg.252]    [Pg.253]    [Pg.262]    [Pg.77]    [Pg.359]    [Pg.113]    [Pg.120]    [Pg.185]    [Pg.128]    [Pg.132]    [Pg.108]    [Pg.227]    [Pg.157]    [Pg.432]    [Pg.130]    [Pg.11]    [Pg.25]    [Pg.528]    [Pg.2088]    [Pg.621]    [Pg.151]    [Pg.152]    [Pg.376]    [Pg.63]    [Pg.1201]   
See also in sourсe #XX -- [ Pg.252 , Pg.253 , Pg.260 , Pg.263 ]




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