This paper examines human impedance perception ability during manipulation of an impedance-controlled robot, especially as regards perception accuracy and differential limen. In the experiments, a subject is instructed to move the handle of an impedance-controlled robot and to perceive the presented value of the robot impedance. Experimental results show that both motor control ability and soma...

The industrial robots are confronted with performing tasks where a contact with their environment occurs. Therefore, a need for control algorithms with position tracking performance and the force control ability appears. Up to date a lot of algorithms were proposed which deal with robot motion and force control. They could be mainly separated into two great classes, namely Hybrid control, where...

Mechanical impedance is the dynamic generalization of stiffness, and determines interactive behavior by definition. Although the argument for explicitly controlling impedance is strong, impedance control has had only a modest impact on robotic manipulator control practice. This is due in part to the fact that it is difficult to select suitable impedances given tasks. A spatial impedance control...

Exoskeletons are utilized extensively in robotic rehabilitation and power augmentation purposes. One of the most recognised control algorithms utilized in this field is the impedance controller. Impedance control approach provides the capability of realizing different rehabilitation exercises by tuning the target impedance gains. Trial and error experimental approach is one of the most common m...

In the past few decades, a variety of rehabilitation robotic exoskeletons have been developed for patients with stroke and traumatic brain injury, which can assist therapists and potentially improve the functional outcomes. Many robotic exoskeleton systems adopted series elastic actuators, which are known to offer a number of advantages over rigid actuators, such as high force/torque fidelity, ...

In this paper, a new impedance function is proposed to achieve accurate force tracking under the presence of uncertainties in robot dynamics and environment models. The new impedance function is formulated on the basis of PID control of the force tracking error which compensates for the unknown environment stiiness and position. The robot dynamics uncertainties are compensated by a simple time-...

This paper proposes an impedance control method that can regulate a virtual impedance between a robot manipulator and external objects using visual information. The conventional impedance control method is not useful in some cases where no interaction force between the arm and its environment exists, although it is one of the most effective control methods for manipulators in contact with the e...

This paper presents the modular design and control of a novel variable impedance compact compliant wearable ankle robot (powered Ankle-Foot Orthosis, AFO) for overground gait rehabilitation and assistance mainly for stroke patients. Design of AFO, its construction, kinematics, working principle, actuation, control etc. are described. A novel variable impedance compact compliant series elastic a...