Keyword: Foot prosthetic below knee, ankle joint multi axis, static equilibrium model
By: Retno Wulan Damayanti & Lobes Herdiman
Accident of roadway occupy the occurence number amputation, the number noted from occurence amputation in Indonesia with biggest contributor equal to 35% and occurence of natural disaster equal to 15%. Impact from amputasi foot make the foot product prosthetic is one of alternative for disabled people of foot. Foot product prosthetic under type knee eksoskeletal is the product used many disabled people of foot. Product foot characteristic prosthetic cannot be produced mass or special customer”s product. This condition require to breakthrough for the development of component up at component add on able to be converted with other component.
Foot prosthetic with system ankle joint multi axis can make a move plantarflexion, dorsiflexion, and eversion – inversion. Move multi axis foot this controlled by polyurathane and ball joint in one axisat SACH adaptor. Movement at foot palm by exploiting the pressure at knee in muscle movement hamstring and quadricep muscle. Foot plantar seen can make a move be like genuiness and stabilize for position single support.
Measurement at foot prosthetic use the model static equilibrium biomechanic at sagital plane indicating that gambling problems stance phase for force and moment yielded from foot prosthetic have the larger ones value than normal foot, on the contrary swing phase foot for force value prosthetic have the value smaller than yielded force of normal foot. At frontal plane indicate that stance phase and swing phase for force and moment yielded the foot prosthetic and normal foot have the stable value.
Measurement to both area for force and moment yielded between normal foot and foot prosthetic of stance phase and swing phase show the yielded force of normal foot have the smaller value than foot prosthetic. So also at swing phase force value at foot prosthetic smaller compared to the normal foot. Matter this means existence of balance pattern between force and moment simultanly of walking to each movement walk phase in one cycle gait.
Research is furthermore require to investigate the device result made to influence center of preasure (CoP) from center of gravity (CoG) to center of mass (CoM) to balance pattern of foot prosthetic used which is used as the product comforts parameter of weared.