This project's purpose was to design and build a custom-made exoskeleton designed to be attached to a patient's leg during the early stages of knee rehabilitation. This exoskeleton used pneumatic muscles to provide assistance in knee movement and provide resistance in later stages of recovery. My task was to develop the hardware systems that would enable this system to operate. The closed-loop control system consisting of electromyography (EMG) sensors and force-feedback transducers was controlled by an Arduino through a custom-designed PCB shield. Upon completion, the results of the research were published in the "National Conference on Undergraduate Research" NCUR, 2020.