By Topic

Frequency-Shaped Impedance Control for Safe Human–Robot Interaction in Reference Tracking Application

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)
Sehoon Oh ; Dept. of Mech. Eng., Sogang Univ., Seoul, South Korea ; Hanseung Woo ; Kyoungchul Kong

In the control of industrial robots, both safety and reference tracking performance are required. For safe human-robot interaction, robots should exhibit low mechanical (or controlled) impedance so that they react to the interaction forces in a compliant manner. On the other hand, the reference tracking requires for the robots to reject exogenous disturbances, which results in an increased impedance. In order to achieve these two conflicting objectives, a frequency-shaped impedance control (FSIC) method is proposed in this paper. The proposed method utilizes the two different functionalities of the disturbance observer (DOB): a disturbance estimation function as an observer and a disturbance rejection function as a feedback controller. Namely, the DOB is utilized as an observer at the frequencies where the robots interact with humans, while it is used as a feedback controller (i.e., disturbance rejection controller) at the frequencies where the reference tracking is required. The proposed approach is realized by shaping a filter of the DOB in the frequency domain so that the impedance is manipulated to achieve both the compliant interaction and reference tracking. The compromised reference tracking performance in the frequency range, where the impedance is set low, can also be supplemented by feedforward control. A typical feedback controller and a feedforward controller are designed in addition to the DOB-controlled system as the whole control system to enhance reference tracking performance and the betterment of stability robustness. The proposed method is verified by experimental results in this paper.

Published in:

Mechatronics, IEEE/ASME Transactions on  (Volume:19 ,  Issue: 6 )