The number of people with a mobility disorder caused by stroke, spinal cord injury (SCI) or other related diseases is increasing rapidly. Damage to central and peripheral nervous systems often leads to a gait impairment and reduced mobility or, in the worst cases, paralysis: even the activities of daily living (ADLs) become quite challenging. Nowadays, with the goal of giving a normal life back to SCI patients, a new technological achievement has been reached: lower-limb exoskeletons. Lower-limb exoskeletons are wearable robotic devices which provide impaired people with the possibility to perform normal ambulatory functions. The features of standing up/sitting down and walking are features that every exoskeleton commercially available has, since they were born in order to enable system-assisted walking for wheelchair users.