Control of underactuated planar hexapedal pronking through a dynamically embedded SLIP monopod

Date
2010
Advisor
Instructor
Source Title
2010 IEEE International Conference on Robotics and Automation
Print ISSN
1050-4729
Electronic ISSN
Publisher
IEEE
Volume
Issue
Pages
4721 - 4727
Language
English
Type
Conference Paper
Journal Title
Journal ISSN
Volume Title
Abstract

Pronking (aka. stotting) is a gait in which all legs are used in synchrony, resulting in long flight phases and large jumping heights that may potentially be useful for mobile robots on rough terrain. Robotic instantiations of this gait suffer from severe pitch instability either due to underactuation, or the lack of sufficient feedback. Nevertheless, the dynamic nature of this gait suggests that the Spring-Loaded Inverted Pendulum Model (SLIP), a very successful predictive model for both natural and robotic runners, would be a good basis for more robust and maneuverable robotic pronking. In this paper, we describe how "template-based control", a controller structure based on the embedding of a simple dynamical "template" within a more complex "anchor" system, can be used to achieve stable and controllable pronking for a planar, underactuated hexapod model. In this context, high-level control of the gait is regulated through speed and height commands to the SLIP template, while the embedding controller based on approximate inverse-dynamics and carefully designed passive dynamics ensures the stability of the remaining degrees of freedom. We show through extensive simulation experiments that unlike existing open-loop alternatives, the resulting control structure provides stability, explicit maneuverability and significant robustness against sensor and actuator noise. ©2010 IEEE.

Course
Other identifiers
Book Title
Keywords
Approximate inverse, Control structure, Controller structures, Degrees of freedom, Dynamic nature, Extensive simulations, Flight phasis, Open loops, Predictive models, Rough terrains, Sensor and actuators, Show through, Spring loaded inverted pendulums, Template-based, Under-actuation, Underactuated, Controllers, Robots, Robotics
Citation
Published Version (Please cite this version)