title: Control and Evaluation of a Powered Transfemoral Prosthesis for Stair Ascent.
abstract: This paper assesses the metabolic effort exerted by three transfemoral amputees, when using a powered knee and ankle prosthesis for stair ascent, relative to ascending stairs with passive knee and ankle prostheses. The paper describes a controller that provides step-over stair ascent behavior reflective of healthy stair ascent biomechanics, and describes its implementation in a powered prosthesis prototype. Stair ascent experiments were performed with three unilateral transfemoral amputee subjects, comparing the oxygen consumption required to ascend stairs using the powered prosthesis (with a step-over gait), relative to using their daily-use energetically passive prostheses (with a step-to gait). Results indicate on average a 24% reduction in oxygen consumption and a 30% reduction in stair ascent timewhen using the powered prosthesis, relative to when using the passive prostheses. All subjects expressed a strong preference for ascending stairs using the powered prosthesis.
authors.forename: Elissa D
authors.initials: ED
authors.lastname: Ledoux
authors.forename: Michael
authors.initials: M
authors.lastname: Goldfarb
mesh_terms: D001186:Artificial Limbs; D011211:Electric Power Supplies; D004867:Equipment Design; D019544:Equipment Failure Analysis; D000067190:Exoskeleton Device; D005246:Feedback; D005260:Female; D005684:Gait; D006801:Humans; D007866:Leg / Q000503:physiopathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D010865:Pilot Projects; D015203:Reproducibility of Results; D012371:Robotics / Q000295:instrumentation* / Q000379:methods; D012680:Sensitivity and Specificity; D016896:Treatment Outcome