The primary function of a lower limb prosthetic device is restoration of ambulation. Proper alignment – the correct spatial relationship between artificial sockets and the natural limb – is paramount to attain an efficient, comfortable gait with a desired loading pattern on the residual leg. Despite advances in prosthetic device design, the clinical alignment process remains subjective and nonsystematic due to a lack of an inexpensive, effective method for quantification of the amputee gait. Gait laboratories provide accurate data for gait monitoring; however cost and lab availability prohibit most patients from this benefit. Economic concerns aside, gait labs do not fill the void of information needed to quantify the alignment process. Observation time and environment are too limited to amass useful information for prosthetic alignment improvement. A more logical and systematic approach to clinical alignment requires the quantification of amputee gait before and after adjustments made by the prosthetist. To be complete this quantification must span extended periods of time and terrain. Thus, there is a patent need for a portable, reliable, and cost effective motion capture system. This project proposes a design for such a system. Comprised of body (prosthetic) mounted inertial sensors – accelerometers and gyroscopes – the system is designed to track the kinematics of the limbs during a walking cycle. The goal of this work is to prove the feasibility of motion capture system using these body mounted sensors. The effectiveness of the system will be judged as its ability to capture planar motion using two (2) accelerometers and one (1) gyroscope mounted on an aluminum bar (simulating a prosthetic device). The design of the system was formulated based on an extensive literature review pertaining to body mounted sensor systems. The rigid structure of the prostheses gives a prosthetic mounted sensor system a distinct advantage over a body mounted system in terms of inverse kinematic calculations.