Development of Ankle Foot Orthosis (AFO) Using Pneumatic Artificial Muscle (PAM)
Ankle foot orthosis (AFO) is commonly used for a patient who had difficulty on their joint weakness of lower limb, which to correct the instabilities and improve gait pattern. Many studies have explored of dorsiflexion and plantarflexion on AFO. However, a few researchers combine the eversion motion on AFO. The eversion motion has been not introduced widely as dorsiflexion and plantarflexion motion and only have minimal data analysis from previous research. The implementation of pneumatic artificial muscle (PAM) as an actuation system was initiated for controlling the AFO which mimics the biological human muscle tendon. Thus, this research introduces the development of AFO using PAM that assists dorsiflexion, plantarflexion and eversion motion. This research started with anthropometry measurement (n=5, age=12 years old) with 18 body dimensions on the lower limb, and applied to AFO design by using Computer Aided Design (CAD) software. The final design of AFO was fabricated by using a 3D printer. The PAM was fabricated and been tested by using a test bed machine to test the PAM performance before being used for AFO. To determine AFO performances, this research performed with normal children (age 12 years old) with two walking conditions which is using passive and active AFO. As a result, AFO performances allowed free ankle movement during stance phase and also allowed to perform proper dorsiflexion by ~5deg which avoids toe drag during swing phase hence avoid the foot drop to occur as well. The AFO shows the eversion motion can move up to ~9deg from the neutral position (0deg) The results from AFO performance by walking trials demonstrated that the newly developed AFO is provided the assisted for foot drop condition which can contribute to the future opportunities with real foot drop syndrome patient.