Lower limb exoskeletons play a crucial role in rehabilitation and compensation of motor functions, benefiting individuals with neuromotor pathologies or muscle weakness. This paper presents the development of a variable impedance knee exoskeleton combined with a motor neuroprosthesis (MNP). The system integrates an expert system to detect sub-phases of gait, a functional electrical stimulation (FES) system, and a magnetorheological (MR) fluid damper. The objective is to provide stability and assistance during gait through real-time algorithms that control the resistance and assistance levels of the exoskeleton.