15 accepted papers
In this study, we propose an interaction control framework for gait assistance and resistance using a robotic exoskeleton. We define a smoothed state variable that represents joint angle movements while walking. Furthermore, a self-feedback controller is designed with the delayed output state. By ap
This paper presents an adjustable knee joint for a wearable robot for the elderly, to provide physical gait assistance. In order to compensate for the translational and rotational movements of the knee in the sagittal plane as well as aligning the frontal plane, the proposed knee joint is implemente…
This letter proposes a multifunctional ankle exoskeleton to safely expand the mobility. By applying torque to the ankle in dorsiflexion and plantarflexion, the exoskeleton prevents foot drop and foot slip and helps the ankle to push off the ground. The exoskeleton includes a remote center-of-motion
We developed a robotic lower-limb exoskeleton for those who have weakened muscle due to aging and experience difficulty in walking or getting up without help. The exoskeleton covering both limbs from the feet to the waist has 6 electric actuators in the hip abduction/adduction, hip extension/flexion…
This letter presents a simulation framework for hip assistance in ankle pathologies. We first constructed the neuromuscular walking model, then designed the parameters for assistance torques for stance and swing legs. The parameter values were determined by carrying out dynamic optimizations that ta
This paper proposes a new concept called “a flexible exoskeleton” and presents the design of a wearable walking assistance device to provide physical gait assistance for the elderly. To overcome some limitations of previous wearable walking assistance devices, 3 novel mechanisms are proposed: 1) fle…
This paper presents an adjustable knee mechanism for walking assistance devices for the elderly to provide physical gait assistance. The adjustable knee mechanism can assist in flexion/extension motions of the knee joint and compensate for the transitional movements of the knee in the sagittal plane…
We propose a novel two-tier gait recognizer using a minimal number of mechanical sensors built into a lower limb exoskeleton. The aim of this recognizer is to offer one-step selection of one of the actions ascending, descending, and level walking during five gaits (stair ascent/descent, slope ascent…
We propose a simulation framework for gait assistance with ankle pathologies. We first construct the neu-romuscular walking model, then design the parameters for assistance torques for stance and swing legs. The parameter values are determined by performing dynamic optimizations which takes into acc…
In this paper, we propose a novel assistance strategy for stair ascent walking using our robotic hip exoskeleton. Our strategy exploits foot contact event estimated by an inertial measurement unit (IMU) and can detect user intention as well as reflect user preference. In our strategy, a gait cycle i…
We have developed a hip exoskeleton for seniors with difficulties in walking due to muscle weakness. The exoskeleton is lightweight and moderate in assistance power compared to other hip exoskeletons in the literature. Its controller estimates user gait phase, walking speed, and ground inclinations
This paper presents a simulation framework for pathological gait assistance with a hip exoskeleton. Previously we had developed an event-driven controller for gait assistance [1]. We now simulate (or optimize) the gait assistance in ankle pathologies (e.g., weak dorsiflexion or plantarflexion). It i…
To control exoskeletons for walking gait assistance, it is of primary importance to control them to act synchronously with the gaits of users. To effectively estimate the gait cycle (or the phase within a stride) of users, we propose a new adaptive frequency oscillator (AFO). While previous AFOs suc…
This paper presents a control method for walking assist with hip-mounted exoskeleton robots. For modeling a user's current walking motion, a novel finite state machine is first constructed. We divide a walking cycle uniformly using the inevitable zero crossing events. When state transitions occur, w…
In this paper, we propose a novel online gait task recognition algorithm for hip exoskeleton. The proposed algorithm provides an automatic and prompt recognition result in just one step based on the relations between both hip joint angles at the moment of foot contact. Gait task recognition is one o…