Study on Stiffness Estimation of Contact Object Using Series Elastic Actuator

Series elastic actuator consists of an actuator and an elastic component connected in series.One of the applications of SEA is an automatic lettuce harvester that can detect and trace ground surface with contact.The contacting force is controlled to be constant in steady state by position control for regulating the length of the elasticity of SEA.This study focuses on an estimation problem of stiffness of the contacting object when SEA is used in such a tracing application.This paper shows the feasibility of the stiffness estimation via experimental result using extended Kalman filter.