Robotics is increasingly being used in the medicine to solve a wide range of problems in a multitude of different fields. Robots are becoming metallic allies for the benefit of the vulnerable, and apparently their place in the healthcare industry is increasing every day. Some of the fields in which these new technological tools have been incorporated are surgery, telemedicine, sterilization, invasive medicine, and rehabilitation. In the last field, exoskeletons are used as orthoses to assist or rehabilitate individuals with locomotor impairments. One type are lower limb exoskeletons, which are used to rehabilitate gait in patients suffering from stroke, accidents, or spinal injurie.