Developing biologically inspired robotic prostheses necessitates precise understanding of the dynamic interaction between amputee, prosthesis, and the environment they act on. In our research, we are instrumenting a biomimetic ankle-foot powered prosthesis prototype with a series of sensory units to estimate the ground reaction forces (GRF) and zero moment point (ZMP) trajectory. The incorporation of this sensory information with a morphologically realistic human model and basic feedback methods will contribute to the development of balance-control strategies in the mentioned device. These strategies will enhance amputees� perception and control of their dynamic stability. With this new generation of robotic ankle-foot prostheses, we are addressing some of the main difficulties that amputees encounter with current passive devices, including non-symmetric gait, increased walking energy cost, and appropriate maintenance of balance during standing and walking.