Fall Protection Framework of Lower Extremity Exoskeleton Walking System Based on Differential Motion Planning

Abstract

Exoskeleton is a wearable power-assisted supporting device that is used to enhance human motion functions such as walking. This research work is an attempt to provide the paraplegic patients with a more stable human-like hands-free walking function. An exoskeleton model for lower extremities, called a Lower Extremity Exoskeleton Robot (LEE Robot), is developed to feature an automatic posture adjustment and walking balance capability. In order to design a better hands free exoskeleton, the advanced modeling, comprehensive analysis and 3D walking simulations for a humanoid bipedal robot are carried out as a basic research to direct the performance improvement and validate the walking stability and posture optimization. The law of balance is also applied in the analysis of kinematics, statics and dynamics to enhance the new exoskeleton design. Moreover, a conceptual framework is proposed and further developed based on the robot differential motion planning and the zero-moment point (ZMP) stability criterion to realize and test for better fall detection, fall protection and fall avoidance when it is walking. The 3D graphical simulation results demonstrate a success for the new exoskeleton design to offer a better hands free and more stable paraplegic walking.