Bohyun Lee Park, Ji Su Park, Shinsuk Kim, Choong Hyun 2024-01-12T06:33:01Z 2024-01-12T06:33:01Z 2023-10-10 2023-11 2234-7593 https://pubs.kist.re.kr/handle/201004/79778 Gait disorders can lower the quality of life of patients. Drop foot, a causative factor of deviated gait patterns, renders patients unable to lift their forefoot towards the body. Hence, a light and compact ankle-foot orthosis (AFO), which is the most common treatment for drop foot, must be designed, especially for patients with impaired lower limb muscles as oxygen consumption increases by 30% per 1.96 N load on their foot. Furthermore, the limited range of ankle angles in the first 10% of the gait cycle (GC) is a major drawback for patients with drop foot compared to healthy individuals. This limited range of ankle angles can be improved by gaining support from an AFO composed of shape memory alloy (SMA) actuators (SMA-AFO). Therefore, in this study, an SMA was used to fabricate a soft actuator to reduce the weight of the AFO. An adaptive frequency oscillator (AO) was implemented in real time for continuous gait phase detection. Walk tests were performed on a treadmill with the SMA-AFO attached to the participants (N = 3). The experimental results showed that the participants could lift their forefoot in the dorsiflexion direction with an ankle angle of 8.75 & DEG; in the first 10% of the GC. Furthermore, the current required to operate the SMA actuator can be supplied to only 45.3% of the GC, reducing the power consumption. Therefore, the proposed SMA-AFO can be used in patients with drop foot. English 한국정밀공학회 Ankle Foot Orthosis for Patients with Drop Foot Using Shape-Memory-Alloy Actuators Article 10.1007/s12541-023-00901-9 1 International Journal of Precision Engineering and Manufacturing, v.24, no.11, pp.2057 - 2072 International Journal of Precision Engineering and Manufacturing 24 11 2057 2072 N scie kci 001072738900001 Engineering, Manufacturing Engineering, Mechanical Engineering Article ENERGY-EXPENDITURE GAIT DISORDERS STIMULATION Ankle foot orthosis Shape memory alloy Actuator Adaptive frequency Oscillator Gait disorder Gait phase detection Drop foot Gait assistance