On the Control of the Berkeley Lower Extremity Exoskeleton (BLEEX)

Interaction Force Estimation for Transparency Control on Wearable Robots Using a Kalman Filter

“…Although essential for a large range of applications, this topic has not been extensively investigated in the wearable robotics community yet. For instance, BLEEX uses a low impedance (high-sensitivity) controller [1] while HAL uses electromyography (EMG). More recently, other works have also investigated admittance control with positive acceleration feedback [5] and interaction force feedback with modelbased gravity compensation [3].…”

“…In these and other typical applications, it is desirable to measure the interaction force between human and the robot. More specifically, this sensory capability may enable or enhance the robot's ability to perform tasks such as load carrying [1], trajectory tracking [2], and being imperceptible (i.e. transparent) to the user [3], [4].…”

Real-Time EMG Driven Lower Limb Actuated Orthosis for Assistance As Needed Movement Strategy

“…They have known a huge expansion in the last decade as they are continually attracting the scientific and the medical community due to the continuous increasing rate of dependent people [16], [17]. Research in this field has started in the sixties and has tended to assist depending people by coupling the exoskeleton with their limbs in the aim of allowing the wearer to regain natural movements [8]. The key issue when dealing with wearable exoskeletons concerns the interaction between wearer and the exoskeleton from a physical or a cognitive point of view and ideally from both [19].…”

“…The key issue when dealing with wearable exoskeletons concerns the interaction between wearer and the exoskeleton from a physical or a cognitive point of view and ideally from both [19]. The most developed exoskeleton research projets are based on physical interaction, through force interfaces, whether by imposing predefined movements [28,13], or by using forces sensors between the exoskeleton and the wearer and/or the inverse dynamics of the wearer body [8,20,5,6]. One of the major drawbacks of this physical interaction mode is the poorness reactivity of the exoskeleton caused by the time delay between the wearer's intention estimation and the control input applied to the exoskeleton [4].…”

“…In the litterature, different works have dealt with the control of exoskeletons. In [8], the authors proposed a control approach based on a scaled compensation of the estimated exoskeleton dynamics. In [30,32], a PD controller is used to stabilize the body of the wearer by guaranteeing balance of the gravity effect.…”