| The background is the broad prospect intelligent structures. Research is on the new and challenging multidisciplinary subject, piezoelectric intelligent structures. Mechanics, electromagnetics, material science, optimal control and mathematical programming are integrated in this dissertation. Contribution is about theoretical analysis and numerical modeling of optimal control for intelligent structures. Details as following:1 Presented a method to increase load capacity of static indeterminate intelligent trusses. By using the coupling property of indeterminate structures, a programming method control model established here, which takes strength of the structure as objective, subjects to constraint of nodal displacement, can make structures work at optimal status. Program has been finished. Numerical simulation results show that the maximum stress in static indeterminate trusses decreased obviously by using this method.2 Control method to make the maximum nodal displacement to be minimized was brought out in order to solve the stiffness problem of precision structures. For intelligent trusses with any kind of actuators, optimal control taking the controlled nodal displacements to be minimized as objective was realized for static determinate trusses and static indeterminate trusses under every kind of loading cases. Computing program simulated it. The control capacity and adaptability of this method were demonstrated by large numbers of numerical examples.3 A multi-objective optimal control model was set up, which takes the maximum stress, the maximum controlled nodal displacement and the energy consumption of the controlled structure as objectives. The reliability, precision and economization are all assured in the control model of intelligent structures. The localization of single objective control model of intelligent structures wereovercome. The model was transformed to a simple and efficient minimize maximum problem and a weighting factors method quadratic programming, respectively. Program corresponding were finished and numerical results of the two methods were compared.4 Taking the precision and control energy consumption as synthesis objective, subjecting to constraints of structural strength and characteristic of actuators, an optimal control model was set up. Research work on precision control of large antenna structures has been finished. For parabolic antenna adopting intelligent structure, the relation between precision of the antenna reflector and the active elongation of actuators was derived by matrix operation method. The control model was dealt with weighting factor method and sequence layer method. Control simulation of simplified planar and complicated spatial antennas were carried out. Numerical results show that the no error large intelligent antenna is realizable even under not much control cost.5 Synthesis properties control of piezoelectric intelligent trusses was realized.　 Mech-electric coupling FEM equations of intelligent structures with piezoelectric actuators were deduced. Two control models were set up for two cases. The models take voltages as control variables; take displacements and displacements, stress, control energy consumption as objectives, respectively. Optimal control of mech-electric coupling intelligent structures was realized. Numerical examples support the theory.6 Synthesis optimal control of intelligent antenna structures embedded piezoelectric actuators was finished. Taking voltages of control as variables, subjecting to constraints of structural strength and limited voltages of actuators, synthesis control model of antenna was established. It was dealt with weighting factors method. Results of several actuator placement cases of a mech-electric coupling antenna were compared. Control simulation was carried out for the elevation from 0( to 90( under load of gravitation. Effecting of some mainparameters has been analyzed. Corresponding computing program was finished and a numerical example verified...
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