Online Body Schema Adaptation through Cost-Sensitive Active Learning

01/26/2021
by   Gonçalo Cunha, et al.
0

Humanoid robots have complex bodies and kinematic chains with several Degrees-of-Freedom (DoF) which are difficult to model. Learning the parameters of a kinematic model can be achieved by observing the position of the robot links during prospective motions and minimising the prediction errors. This work proposes a movement efficient approach for estimating online the body-schema of a humanoid robot arm in the form of Denavit-Hartenberg (DH) parameters. A cost-sensitive active learning approach based on the A-Optimality criterion is used to select optimal joint configurations. The chosen joint configurations simultaneously minimise the error in the estimation of the body schema and minimise the movement between samples. This reduces energy consumption, along with mechanical fatigue and wear, while not compromising the learning accuracy. The work was implemented in a simulation environment, using the 7DoF arm of the iCub robot simulator. The hand pose is measured with a single camera via markers placed in the palm and back of the robot's hand. A non-parametric occlusion model is proposed to avoid choosing joint configurations where the markers are not visible, thus preventing worthless attempts. The results show cost-sensitive active learning has similar accuracy to the standard active learning approach, while reducing in about half the executed movement.

READ FULL TEXT

Authors

page 1

page 4

10/13/2020

Whole-Body MPC and Online Gait Sequence Generation for Wheeled-Legged Robots

The additional degrees of freedom and missing counterparts in nature mak...
11/19/2017

Trajectory-Optimized Sensing for Active Search of Tissue Abnormalities in Robotic Surgery

In this work, we develop an approach for guiding robots to automatically...
12/07/2019

Phase Portraits as Movement Primitives for Fast Humanoid Robot Control

Currently, usual approaches for fast robot control are largely reliant o...
04/19/2018

Task-centric Optimization of Configurations for Assistive Robots

Robots can provide assistance to a human by moving objects to locations ...
05/19/2021

Active Visual SLAM with independently rotating camera

In active Visual-SLAM (V-SLAM), a robot relies on the information retrie...
03/12/2021

Agile Actions with a Centaur-Type Humanoid: A Decoupled Approach

The kinematic features of a centaur-type humanoid platform, combined wit...
07/20/2016

The encoding of proprioceptive inputs in the brain: knowns and unknowns from a robotic perspective

Somatosensory inputs can be grossly divided into tactile (or cutaneous) ...
This week in AI

Get the week's most popular data science and artificial intelligence research sent straight to your inbox every Saturday.