Intrinsically Backdrivable Hydraulic Servovalve for Interactive Robot Control

Sunkyum Yoo1, Woongyong Lee1, Wan Kyun Chung1

  • 1POSTECH

Details

Category

Regular Papers

Sessions

09:55 - 11:10 | Tue 30 May | Room 4011 | TUA1

Actuators 1

Full Text

Abstract

There has been consistent trials to make a hydraulic actuator to be effective in interactive robot applications, which also requires high power, durability. However, conventional strategies for this goal, like force/torque servo control or adding elastic component, suffered from complexity, sensor problems and reduced system robustness. In this paper, we show that introducing backdrivability to hydraulic system may be an ultimate solution to construction of interactive hydraulic robot systems, with analyzing the advantages of backdrivability for this application. Also, we show that backdrivability of valve-controlled hydraulic system can be achieved by adding load pressure feedback mechanism on the spool of a servovalve, with using similarity of its dynamics structure of flexible joint robot. Finally, we show that the derived backdrivable servovalve dynamics is actually a dynamics of pressure control valve, with experiments which verify the analyzed advantages of backdrivability.

Additional Information

No information added

Video

No videos found

Summary

  • Back-drivability brings force transmission, low gear ratio and low output impedance to the mechanical systems.
  • Conventional servovalve-based Hydraulic actuators lack the capability to interact with the environment.
  • Introduction of chamber pressure feedback mechanism on the spool dynamics brings back-drivablity.