|Reference Type||Online Database|
|Author(s)||Herzog, A; Righetti, L; Grimminger, F; Pastor, P; Schaal, S|
|Title||Experiments with a hierarchical inverse dynamics controller on a torque-controlled humanoid|
|Journal/Conference/Book Title||Arxiv preprint arXiv:1305.2042|
|Keywords||hierarchical control, inverse dynamics, locomotion, balance control, biped, contact interaction|
|Abstract||Recently several hierarchical inverse dynamics controllers based on quadratic
programs have been proposed
for application to torque controlled robots.
They have important theoretical benefits but have never been implemented on
a torque controlled robot where model inaccuracies and real-time computation
requirements can be problematic.
In this contribution we present experimental results for the control of the lower body of a
humanoid robot using these algorithms.
We propose a simplification of the optimization problem that allows us to decrease computation
time enough to implement it in a fast torque control loop.
Experiments demonstrate the applicability of the approach.
In a first experiment, we implement a momentum-based balance controller which
shows robust performance in face of unknown disturbances.
In a second experiment, a tracking task is evaluated to demonstrate the performance
of the controller with more complicated hierarchies.
Our results show that hierarchical inverse dynamics controllers can be efficiently used
for feedback control of humanoid robots and that momentum-based balance control
can be efficiently implemented on a real robot.|
|Link to PDF||http://arxiv.org/pdf/1305.2042v2|