| This dissertation proposes a theory for motion control in large flexible structures. The control approach can be classified as semiactive control because the technique only requires the dynamic alteration of system stiffnesses, an approach that requires minimal energy to implement. By adjusting the structural stiffness, the modal energy profile of the structure can be dynamically adjusted to any desired makeup. One important application is in transferring energy from lower order modes of vibration into higher order modes where the energy is dissipated more quickly by damping within the structure and the deflection is smaller.; The theoretical analysis of the energy transfer technique is presented in this dissertation. This energy transfer theory is supported, in both free vibration and forced vibration cases, by computer simulation results of two different systems (a spring-mass system and a truss structure) as well as laboratory experimental results on a small three- level-building model. Experiments show that the technique is robust to mismodelling. |
