Passive Exoskeleton Design for Human Motion Analysis
Motivation and Approach
In this research, a 7-DOF passive exoskeleton is designed to combine kinematic sensing and human joint torque estimation. The designed passive exoskeleton mainly allows motions in the sagial plane. Several motion sensors and force sensors are utilized including encoders, gyroscopes, and smart shoes; therefore, the joint kinematics and ground contact forces can be measured. We also developed a dynamic model of human walking for estimating the human joint torque. Since the kinematic constraints of the lower-limb extremity during walking vary upon gait phases, the walking dynamic model is described by multiple sub-dynamic models derived using Lagrangian mechanics.
Hardware development of the 7-DOF passive exoskeleton
Main Results
The joint kinematics measurement and torque estimation were veri ed by experiments. A healthy male subject with a normal gait pattern wore the exoskeleton suit and walked on a treadmill with a constant speed. The proposed passive exoskeleton could measure joint kinematics and estimate joint torque accurately as shown in the figure below.
Joint torque estimation results
Recent Key Publications
- K. Kanjanapas and M. Tomizuka, "7 Degrees of Freedom Passive Exoskeleton for Human Gait Analysis: Human Joint
Motion Sensing and Torque Estimation During Walking," in Proceedings of IFAC Symposium on Mechatronic Systems,
pp. 285-292, 2013.