Autonomous Robots

, Volume 42, Issue 1, pp 1–17 | Cite as

Robotic assembly solution by human-in-the-loop teaching method based on real-time stiffness modulation

  • Luka PeternelEmail author
  • Tadej Petrič
  • Jan Babič


We propose a novel human-in-the-loop approach for teaching robots how to solve assembly tasks in unpredictable and unstructured environments. In the proposed method the human sensorimotor system is integrated into the robot control loop though a teleoperation setup. The approach combines a 3-DoF end-effector force feedback with an interface for modulation of the robot end-effector stiffness. When operating in unpredictable and unstructured environments, modulation of limb impedance is essential in terms of successful task execution, stability and safety. We developed a novel hand-held stiffness control interface that is controlled by the motion of the human finger. A teaching approach was then used to achieve autonomous robot operation. In the experiments, we analysed and solved two part-assembly tasks: sliding a bolt fitting inside a groove and driving a self-tapping screw into a material of unknown properties. We experimentally compared the proposed method to complementary robot learning methods and analysed the potential benefits of direct stiffness modulation in the force-feedback teleoperation.


Human-in-the-loop Robot learning Compliant assembly Human–robot interface Teleoperation 



The authors would like to thank Barry Ridge for narrating the supplementary video.

Supplementary material

Supplementary material 1 (mp4 20490 KB)

Supplementary material 2 (mp4 2391 KB)


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  1. 1.Department of Automation Biocybernetics and RoboticsJožef Stefan InstituteLjubljanaSlovenia
  2. 2.HRII Lab, Department of Advanced RoboticsIstituto Italiano di TechnologiaGenoaItaly

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