This letter presents an adaptive impedance control architecture for robotic teleoperation of contact tasks featuring continuous interaction with the environment. We use Learning from Demonstration (LfD) as a framework to learn variable stiffness policies. Then, learnt state-varying is used command remote manipulator, so adapt its environment based on sensed forces. Our system only relies on-board torque sensors commercial manipulator and it does not require any additional hardware or user...

This article presents a hierarchical passivity-based compliance controller that exploits robot redundancy and aims at achieving an impedance behavior with time-varying stiffness on all the priority levels. Unfortunately, this gives rise to certain control actions lead loss of safety-critical passivity feature. To deal problem, we employ concept virtual <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">energy tanks</i> keep track violating...

In this paper, we present a controller that combines motion generation and control in one loop, to endow robots with reactivity safety. particular, propose approach enables follow the plan of first order Dynamical System (DS) variable stiffness profile, closed loop configuration where is always aware current robot state. This allows desired path an interactive behavior dictated by stiffness. We also two solutions enable velocity manner similar trajectory tracking controllers, while...

Vibrotactile biofeedback can improve balance and consequently be helpful in fall prevention. However, it remains unclear how different types of stimulus presentations affect not only trunk tilt, but also Center Pressure (CoP) displacements, whether an instruction on to move contributes a better understanding vibrotactile feedback.Based lower back tilt angles (L5), we applied individualized multi-directional feedback the upper torso by haptic vest 30 healthy young adults. Subjects were...

Abstract Besides anthropometric variables, high-order body representations have been hypothesised to influence postural control. However, this has not directly tested before. Moreover, some studies indicate that sex moderates the relationship of anthropometry and Therefore, as a proof concept we investigated association with control well participants’ sex/gender. Body image measures were assessed figural drawing task. schema was by covert an overt sway measured during normal bipedal quiet...

Kinematic redundancy significantly improves the dexterity and flexibility of robotic manipulators. The redundant degrees freedom can be exploited to fulfill additional tasks that executed without disturbing primary task. In this work, we investigate how a time varying impedance behavior embedded into manipulators where it is desired achieve such both for null space tasks. A passivity based controller developed, relying on concept energy tanks which are filled by dissipated power in system,...

It lies in human nature to properly adjust the muscle force perform a given task successfully. While transferring this control ability robots has been big concern among researchers, there is no attempt make robot learn how impedance solely based on visual observations. Rather, research tele-impedance usually relies special devices such as EMG sensors, which have less accessibility well generalization compared simple RGB webcams. In letter, we propose system for vision-based of robots,...

Abstract In this paper, we present a novel learning-based shared control framework. This framework deploys first-order Dynamical Systems (DS) as motion generators providing the desired reference motion, and Variable Stiffness (VSDS) (Chen et al. 2021) for haptic guidance. We show how to shape several features of our controller in order achieve authority allocation, local refinement, addition inherent ability automatically synchronize with human state during joint task execution. validate...

Surface tension forces, pressure and drag forces arise once a micro-particle comes into contact with gas bubble or biological cell in diverse physical biomedical applications such as targeted therapy, sorting, characterization of cancer cells. We experimentally demonstrate that these can be estimated, scaled-up to the sensory range human operator, sensed during transparent bilateral tele-manipulation using an electromagnetic system haptic device. find good agreement between estimated...

In this work, we propose a novel formulation for energy tanks based on Control Barrier Functions (CBF). Our approach is able to handle simultaneously constraints ensure passivity, as well enforce power limits in the system enhance safety. Furthermore, our overcomes discrete switching nature of classical tanks, ensuring smooth control commands. To achieve desiderata, formulate tank second order dynamical system, where exploit CBF and Higher-Order obtain theoretical guarantees fulfilling...

In this paper, an autonomy allocation approach is proposed for bilateral teleoperation systems to improve user performance under suboptimal communication networks. To achieve this, time-varying quality metrics such as delay and jitter are continuously monitored on the teleoperated side, level dynamically adjusted based network quality. An autonomous agent also deployed leveraging preexisting task knowledge shared autonomy. Additionally, a time-domain passivity employed maintain channel...

In this paper, we present an approach to encode variable stiffness behaviors into Dynamical Systems (DS), controlled in a closed-loop configuration. Given desired robot motion represented as first order DS, well profile, our generates new called Variable Stiffness DS (VSDS), that controls the and impedance simultaneously. The shows symmetric spring-like attraction behavior around reference path described by one of integral curves with interactive prescribed stiffness. Our is validated...

This work presents a novel shared control architecture dedicated to teleoperated contact tasks. We use Learning from demonstration as framework learn task model that encodes the desired motions, forces and stiffness profiles. Then, learnt information is used by Virtual Fixture (VF) guide human operator along nominal trajectory captures dynamics, while simultaneously adapting remote robot impedance. Furthermore, we provide haptic guidance in human-aware manner. To end, propose law eliminates...

Kinematic redundancy enhances the dexterity and flexibility of robot manipulators. By exploiting redundant degrees freedom, auxiliary null space tasks can be carried out in addition to primary task. Such are often formulated terms a performance or safety criterion that shall minimized. If optimization criterion, however, is defined global terms, then it directly affected by As consequence, task achievement may unnecessarily detrimented main In modifying via constraint relaxation, possible...

In this paper, we present a controller that combines motion generation and control in one loop, to endow robots with reactivity safety. particular, propose approach enables follow the plan of first order Dynamical System (DS) variable stiffness profile, closed loop configuration where is always aware current robot state. This allows desired path an interactive behavior dictated by stiffness. We also two solutions enable velocity manner similar trajectory tracking controllers, while...

In this paper, we present a novel learning-based shared control framework. This framework deploys first-order Dynamical Systems (DS) as motion generators providing the desired reference motion, and Variable Stiffness (VSDS) \cite{chen2021closed} for haptic guidance. We show how to shape several features of our controller in order achieve authority allocation, local refinement, addition inherent ability automatically synchronize with human state during joint task execution. validate approach...

Recently, several approaches have attempted to combine motion generation and control in one loop equip robots with reactive behaviors, that cannot be achieved traditional time-indexed tracking controllers. These however mainly focused on positions, neglecting the orientation part which can crucial many tasks e.g. screwing. In this work, we propose a algorithm adapts robot's rotational impedance closed-loop manner. Given first-order Dynamical System representing an plan desired stiffness...

Recently, several approaches have attempted to combine motion generation and control in one loop equip robots with reactive behaviors, that cannot be achieved traditional time-indexed tracking controllers. These however mainly focused on positions, neglecting the orientation part which can crucial many tasks e.g. screwing. In this work, we propose a algorithm adapts robot's rotational impedance closed-loop manner. Given first-order Dynamical System representing an plan desired stiffness...