Dynamic Analysis and State Estimation of Wearable Extra Robotic Limbs for Physical Assistance and Load Reduction in Missile-mounting

摘要

Abstract In order to fully exploit the potential in the field of human augmentation, to help the wearer fulfil the task of physical assistance and load reduction, a new type of wearable robot that can perform tasks in close coordination with the wearer and assist the wearer with extra arms and legs secured around the body is presented. The system, named extra auxiliary robotic upper limbs-lower extremity exoskeleton (EARUL-LEE), consists of two additional robotic arms worn through a backpack around the upper body and two exoskeleton legs attached to the lower body tightly. The EARUL-LEE can assist the wearer by holding objects, lifting weights and streamlining the execution of a task. If the EARUL-LEE performs movements closely coordinated with the wearer and exhibits human-like dynamics, it might be incorporated into the body representation and perceived as parts of the wearer’s body. The EARUL-LEE can work closely with the soldier by supporting and securing the human body when lifting a missile, and more. Although the EARUL-LEE control performance is hindered by unpredictable disturbances due to involuntary motions of the soldier, which include postural sway and physiological tremor, the dynamic analysis the human-EARUL-LEE hybrid system include the models of human-induced disturbance based on biomechanics literature, extra auxiliary robotic upper limbs and lower extremity exoskeleton and state estimation method based on an orthogonal least squares for the EARUL-LEE, aimed to perform the missile-mounting for aircrafts on the ground or decks in tight coordination with the soldier as a close co-worker are presented here. Via the current study, the orthogonal least squares (OLS) filter is constructed to estimate the state and its performance is evaluated in terms of error covariance. The simulation results show that the orthogonal least squares filter can tracking desired trajectory and its convergence is better than without any filters. The results can be used to control the EARUL-LEE accordingly with the used end effectors and provide a method for improving the accuracy and stabilizing the human body and the EARUL-LEE.