There are numerous difficulties in designing a prosthetic device such as an artificial limb to mimic a real human limb. One of the prior challenges is the stability of the lower limb prosthesis under the physical constraints of real terrain. The prosthetic devices designed under laboratory conditions are limited in their applicability to real-life environments. In this work external perturbations applied to a real foot are taken into account and incorporated in the Ankle-Knee Active prosthesis dynamic model such as vertical and horizontal ground reaction forces and external perturbation applied to the ankle joint from uneven terrain. A combination of fuzzy logic with a PID controller is, then, implemented to control the designed model under these external perturbations during a normal walking gait cycle.