Research has found significant potential for ultrasound actuation of shape memory polymers (SMPs) in several fields such as biomedical and electronic devices among others. Example applications range from controlled drug delivery containers to soft robotics and flexible electronics located in otherwise inaccessible places or hazardous environments, where direct external heating is not possible. SMPs can be manipulated into any temporary shape and later recover to their stress-free permanent shape when triggered with external stimuli such as heat. Focused ultrasound (FU) has the ability to induce localized heating and activate multiple intermediate shapes and achieve complete shape recovery in the polymer, non-invasively and remotely. In addition, FU has a superior capability for temporal and spatial control of shape recovery by adjusting sample size, ultrasound frequency, exposure time and intensity as well as the position of ultrasound focusing. In this paper, indirect actuation of the thermally-induced shape-memory effect of SMPs by FU is studied theoretically and experimentally with a focus on the acoustic field, medium, geometric and material properties. The changes in thermomechanical properties, during FU actuation, are studied through dynamic mechanical analyzer tests. Using these properties, an analytical acoustic-thermo-elastic dynamic model is developed to predict the shape memory response of a SMP cantilever beam, considering acoustic and geometric nonlinearities. The governing equations of motion are derived using reduced order modeling and solved by perturbation techniques. Having obtained an analytical expression for the shape recovery of the beam as a function of acoustic parameters, experimental validations for a cantilever SMP beam exposed to FU are performed. The model has the ability to successfully estimate the variation in the amount of shape recovery due to the change in source frequency of the transducer and peak acoustic pressure field inside SMP domain without the need of analyzing any intermediary acoustic/thermal/elastic behavior.