Using linear actuators at human-interactive robotic lab
During the posture phase of walk, the instrumented vibrating platform applies pseudo-random rotation perturbation to the ankle using 12 volt actuators. Dorsiflexion, plantar flexion and inversion-eversion movement recorded by a camera are some of the resulting movement of the ankle. A major importance of the platform is its ability to estimate the mechanical impedance of the ankle. The power is transferred from the actuators module using a Bowden cable to the footplate module. This is done while providing the system with a low profile. The robotic ankle foot is favorable for an agile walker since it is capable of various movements. The ankle foot is tailored to meet the users’ needs. Bowden cables are used to connect the actuation system to the prosthesis and the actuation system can be mounted or dismounted easily based on the users’ activities.
Research is still being conducted to find a platform that has a circular treadmill and a gait emulator. The platform allows for repeatable experiment on the prototypes steerable prosthesis. The prototype is expected to accommodate diverse surface profiles and diverse radiuses of turn thus enhancing maneuverability for navigating slopes. This research is expected to have tremendous impacts and the prototype is intended to imitator the mechanical functionality of a human ankle in all movements. The prototype is designed to be practical, light weight and tendon driven thus enhancing agility during turning. It will also have the ability to accommodate changes in the ground’s profile and slope.
The mechanical impedance of the human ankle is responsible for locomotion and thus very important. Studies are being conducted to estimate the impedence of the ankle in various periods of the walk. The results of this study will be used to develop an assistive robotic ankle foot that will imitate the time changing mechanism of a human ankle during different circumstances of gait.