The number of people who need rehabilitation increases day by day because of reasons such as laceration, aging, work accidents and etc. Therefore, the need of rehabilitation aids is constantly increasing. There are many research studies about assistive technologies in rehabilitation. Especially, rehabilitation robots have a great importance. Existing rehabilitation robot studies have mostly foc...

In this paper, neural network force control is presented. Under the framework of impedance control, neural network is used to compensate for all the uncertainties from robot dynamics and unknown environment. Modi ed simple impedance function is realized after the convergence of neural network. Learning algorithms for neural network to minimize force error directly are designed. As a test-bed, t...

This paper proposes an impedance control method for redundant manipulators, which can control not only the endpoint impedance using one of the conventional impedance control methods, but the joint impedance which has no effects on the end-point impedance. First, a sufficient condition for the joint impedance controller is derived. Then, the optimal controller for a given desired joint impedance...

In recent years a lot of versatile robots have been developed to work in environments with human. However they are not sufficiently flexible nor safe in terms of interaction with human. In our approach we focused on hand and eye coordination in order to establish a flexible robot control, in which a robot recognizes its environment from the input camera images and equips a soft contacting strat...

This paper presents a proposed adaptive impedance control that derived based on Center of Mass (CoM) of the hexapod robot for walking on the bottom of water or seabed. The study has been carried out by modeling the buoyancy force following the restoration force to achieve the drowning level according to the Archimedes’ principle. The restoration force need to be positive in order to ensure robo...

A primary goal of robotic rehabilitation is to provide repeatable, cost-effective therapy that is comparable to or better than conventional therapy. Lower-limb rehabilitation robots can be separated into robot-dominant devices, where the robot drives the motion of the human, and cooperative devices, where the robot and the human share control. Robot-dominant approaches have been shown to be les...

In impedance control for force tracking, it is well known that the reference trajectory of the robot is calculated from known environmental stiffness. The authors present a simple technique for determining the reference trajectory under the condition that the environment is unknown. The technique is developed based on the replacement of the unknown stiffness with a function of the measured forc...

This article presents preliminary stochastic estimates of the multi-variable human ankle mechanical impedance. We employed Anklebot, a rehabilitation robot for the ankle, to provide torque perturbations. Time histories of the torques in Dorsi-Plantar flexion (DP) and Inversion-Eversion (IE) directions and the associated angles of the ankle were recorded. Linear timeinvariant transfer functions ...