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Control of Biped Robot

Kjær, Martin Ansbjerg (2003) In Master's Thesis Department of Control Engineering, Aalborg University, Denmark
Department of Automatic Control
Abstract
In this project the control of the gait of a seven degree of freedom biped robot restricted to the sagittal plane is investigated. The gait of the biped is modeled as a hybrid system of four states, corresponding to four relevant phases of the gait. The modeling of the impact between the feet and the ground results in a non-continuous relationship between the coordinate velocities before and after the impact, which is included in the hybrid model. During some of the phases of the gait, the system is under-actuated, and a controller is designed to handle this. An input-output feedback linearization is designed, transferring the system to a number of double integrators, which are stabilized using backstepping control. It is proven that the... (More)
In this project the control of the gait of a seven degree of freedom biped robot restricted to the sagittal plane is investigated. The gait of the biped is modeled as a hybrid system of four states, corresponding to four relevant phases of the gait. The modeling of the impact between the feet and the ground results in a non-continuous relationship between the coordinate velocities before and after the impact, which is included in the hybrid model. During some of the phases of the gait, the system is under-actuated, and a controller is designed to handle this. An input-output feedback linearization is designed, transferring the system to a number of double integrators, which are stabilized using backstepping control. It is proven that the search for a stable limit cycle for the gait can be carried out evaluating the zero dynamics, resulting from the under-actuation. The zero dynamics is two dimensional, and the Poincaré-Bendixson criterion can therefore be applied. A method for applying this criterion is given, along with a motivation for locating the limit cycle. No successful simulations has been carried out, because of implementation errors. (Less)
Please use this url to cite or link to this publication:
author
Kjær, Martin Ansbjerg
supervisor
organization
year
type
H3 - Professional qualifications (4 Years - )
subject
publication/series
Master's Thesis Department of Control Engineering, Aalborg University, Denmark
language
English
id
8848138
date added to LUP
2016-03-19 17:39:09
date last changed
2016-03-30 14:58:54
@misc{8848138,
  abstract     = {In this project the control of the gait of a seven degree of freedom biped robot restricted to the sagittal plane is investigated. The gait of the biped is modeled as a hybrid system of four states, corresponding to four relevant phases of the gait. The modeling of the impact between the feet and the ground results in a non-continuous relationship between the coordinate velocities before and after the impact, which is included in the hybrid model. During some of the phases of the gait, the system is under-actuated, and a controller is designed to handle this. An input-output feedback linearization is designed, transferring the system to a number of double integrators, which are stabilized using backstepping control. It is proven that the search for a stable limit cycle for the gait can be carried out evaluating the zero dynamics, resulting from the under-actuation. The zero dynamics is two dimensional, and the Poincaré-Bendixson criterion can therefore be applied. A method for applying this criterion is given, along with a motivation for locating the limit cycle. No successful simulations has been carried out, because of implementation errors.},
  author       = {Kjær, Martin Ansbjerg},
  language     = {eng},
  note         = {Student Paper},
  series       = {Master's Thesis Department of Control Engineering, Aalborg University, Denmark},
  title        = {Control of Biped Robot},
  year         = {2003},
}