2,195 research outputs found
Guided Filtering based Pyramidal Stereo Matching for Unrectified Images
Stereo matching deals with recovering quantitative
depth information from a set of input images, based on the visual
disparity between corresponding points. Generally most of the
algorithms assume that the processed images are rectified. As
robotics becomes popular, conducting stereo matching in the
context of cloth manipulation, such as obtaining the disparity
map of the garments from the two cameras of the cloth folding
robot, is useful and challenging. This is resulted from the fact of
the high efficiency, accuracy and low memory requirement under
the usage of high resolution images in order to capture the details
(e.g. cloth wrinkles) for the given application (e.g. cloth folding).
Meanwhile, the images can be unrectified. Therefore, we propose
to adapt guided filtering algorithm into the pyramidical stereo
matching framework that works directly for unrectified images.
To evaluate the proposed unrectified stereo matching in terms of
accuracy, we present three datasets that are suited to especially
the characteristics of the task of cloth manipulations. By com-
paring the proposed algorithm with two baseline algorithms on
those three datasets, we demonstrate that our proposed approach
is accurate, efficient and requires low memory. This also shows
that rather than relying on image rectification, directly applying
stereo matching through the unrectified images can be also quite
effective and meanwhile efficien
Single-Shot Clothing Category Recognition in Free-Configurations with Application to Autonomous Clothes Sorting
This paper proposes a single-shot approach for recognising clothing
categories from 2.5D features. We propose two visual features, BSP (B-Spline
Patch) and TSD (Topology Spatial Distances) for this task. The local BSP
features are encoded by LLC (Locality-constrained Linear Coding) and fused with
three different global features. Our visual feature is robust to deformable
shapes and our approach is able to recognise the category of unknown clothing
in unconstrained and random configurations. We integrated the category
recognition pipeline with a stereo vision system, clothing instance detection,
and dual-arm manipulators to achieve an autonomous sorting system. To verify
the performance of our proposed method, we build a high-resolution RGBD
clothing dataset of 50 clothing items of 5 categories sampled in random
configurations (a total of 2,100 clothing samples). Experimental results show
that our approach is able to reach 83.2\% accuracy while classifying clothing
items which were previously unseen during training. This advances beyond the
previous state-of-the-art by 36.2\%. Finally, we evaluate the proposed approach
in an autonomous robot sorting system, in which the robot recognises a clothing
item from an unconstrained pile, grasps it, and sorts it into a box according
to its category. Our proposed sorting system achieves reasonable sorting
success rates with single-shot perception.Comment: 9 pages, accepted by IROS201
Learning to Dress {3D} People in Generative Clothing
Three-dimensional human body models are widely used in the analysis of human
pose and motion. Existing models, however, are learned from minimally-clothed
3D scans and thus do not generalize to the complexity of dressed people in
common images and videos. Additionally, current models lack the expressive
power needed to represent the complex non-linear geometry of pose-dependent
clothing shapes. To address this, we learn a generative 3D mesh model of
clothed people from 3D scans with varying pose and clothing. Specifically, we
train a conditional Mesh-VAE-GAN to learn the clothing deformation from the
SMPL body model, making clothing an additional term in SMPL. Our model is
conditioned on both pose and clothing type, giving the ability to draw samples
of clothing to dress different body shapes in a variety of styles and poses. To
preserve wrinkle detail, our Mesh-VAE-GAN extends patchwise discriminators to
3D meshes. Our model, named CAPE, represents global shape and fine local
structure, effectively extending the SMPL body model to clothing. To our
knowledge, this is the first generative model that directly dresses 3D human
body meshes and generalizes to different poses. The model, code and data are
available for research purposes at https://cape.is.tue.mpg.de.Comment: CVPR-2020 camera ready. Code and data are available at
https://cape.is.tue.mpg.d
A 3D descriptor to detect task-oriented grasping points in clothing
© 2016. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Manipulating textile objects with a robot is a challenging task, especially because the garment perception is difficult due to the endless configurations it can adopt, coupled with a large variety of colors and designs. Most current approaches follow a multiple re-grasp strategy, in which clothes are sequentially grasped from different points until one of them yields a recognizable configuration. In this work we propose a method that combines 3D and appearance information to directly select a suitable grasping point for the task at hand, which in our case consists of hanging a shirt or a polo shirt from a hook. Our method follows a coarse-to-fine approach in which, first, the collar of the garment is detected and, next, a grasping point on the lapel is chosen using a novel 3D descriptor.
In contrast to current 3D descriptors, ours can run in real time, even when it needs to be densely computed over the input image. Our central idea is to take advantage of the structured nature of range images that most depth sensors provide and, by exploiting integral imaging, achieve speed-ups of two orders of magnitude with respect to competing approaches, while maintaining performance. This makes it especially adequate for robotic applications as we thoroughly demonstrate in the experimental section.Peer ReviewedPostprint (author's final draft
Robotic system for garment perception and manipulation
Mención Internacional en el título de doctorGarments are a key element of people’s daily lives, as many
domestic tasks -such as laundry-, revolve around them. Performing
such tasks, generally dull and repetitive, implies devoting
many hours of unpaid labor to them, that could be freed
through automation. But automation of such tasks has been traditionally
hard due to the deformable nature of garments, that
creates additional challenges to the already existing when performing
object perception and manipulation. This thesis presents
a Robotic System for Garment Perception and Manipulation
that intends to address these challenges.
The laundry pipeline as defined in this work is composed
by four independent -but sequential- tasks: hanging, unfolding,
ironing and folding. The aim of this work is the automation of
this pipeline through a robotic system able to work on domestic
environments as a robot household companion.
Laundry starts by washing the garments, that then need to
be dried, frequently by hanging them. As hanging is a complex
task requiring bimanipulation skills and dexterity, a simplified
approach is followed in this work as a starting point, by using
a deep convolutional neural network and a custom synthetic
dataset to study if a robot can predict whether a garment will
hang or not when dropped over a hanger, as a first step towards
a more complex controller.
After the garment is dry, it has to be unfolded to ease recognition
of its garment category for the next steps. The presented
model-less unfolding method uses only color and depth information
from the garment to determine the grasp and release
points of an unfolding action, that is repeated iteratively until
the garment is fully spread.
Before storage, wrinkles have to be removed from the garment.
For that purpose, a novel ironing method is proposed,
that uses a custom wrinkle descriptor to locate the most prominent
wrinkles and generate a suitable ironing plan. The method
does not require a precise control of the light conditions of
the scene, and is able to iron using unmodified ironing tools
through a force-feedback-based controller.
Finally, the last step is to fold the garment to store it. One
key aspect when folding is to perform the folding operation in a precise manner, as errors will accumulate when several
folds are required. A neural folding controller is proposed that
uses visual feedback of the current garment shape, extracted
through a deep neural network trained with synthetic data, to
accurately perform a fold.
All the methods presented to solve each of the laundry pipeline
tasks have been validated experimentally on different robotic
platforms, including a full-body humanoid robot.La ropa es un elemento clave en la vida diaria de las personas,
no sólo a la hora de vestir, sino debido también a que muchas
de las tareas domésticas que una persona debe realizar diariamente,
como hacer la colada, requieren interactuar con ellas.
Estas tareas, a menudo tediosas y repetitivas, obligan a invertir
una gran cantidad de horas de trabajo no remunerado en
su realización, las cuales podrían reducirse a través de su automatización.
Sin embargo, automatizar dichas tareas ha sido
tradicionalmente un reto, debido a la naturaleza deformable de
las prendas, que supone una dificultad añadida a las ya existentes
al llevar a cabo percepción y manipulación de objetos a
través de robots. Esta tesis presenta un sistema robótico orientado
a la percepción y manipulación de prendas, que pretende
resolver dichos retos.
La colada es una tarea doméstica compuesta de varias subtareas
que se llevan a cabo de manera secuencial. En este trabajo,
se definen dichas subtareas como: tender, desdoblar, planchar
y doblar. El objetivo de este trabajo es automatizar estas tareas
a través de un sistema robótico capaz de trabajar en entornos
domésticos, convirtiéndose en un asistente robótico doméstico.
La colada comienza lavando las prendas, las cuales han de
ser posteriormente secadas, generalmente tendiéndolas al aire
libre, para poder realizar el resto de subtareas con ellas. Tender
la ropa es una tarea compleja, que requiere de bimanipulación
y una gran destreza al manipular la prenda. Por ello, en este
trabajo se ha optado por abordar una versión simplicada de
la tarea de tendido, como punto de partida para llevar a cabo
investigaciones más avanzadas en el futuro. A través de una red
neuronal convolucional profunda y un conjunto de datos de
entrenamiento sintéticos, se ha llevado a cabo un estudio sobre
la capacidad de predecir el resultado de dejar caer una prenda
sobre un tendedero por parte de un robot. Este estudio, que
sirve como primer paso hacia un controlador más avanzado,
ha resultado en un modelo capaz de predecir si la prenda se
quedará tendida o no a partir de una imagen de profundidad
de la misma en la posición en la que se dejará caer.
Una vez las prendas están secas, y para facilitar su reconocimiento
por parte del robot de cara a realizar las siguientes tareas, la prenda debe ser desdoblada. El método propuesto en
este trabajo para realizar el desdoble no requiere de un modelo
previo de la prenda, y utiliza únicamente información de profundidad
y color, obtenida mediante un sensor RGB-D, para
calcular los puntos de agarre y soltado de una acción de desdoble.
Este proceso es iterativo, y se repite hasta que la prenda se
encuentra totalmente desdoblada.
Antes de almacenar la prenda, se deben eliminar las posibles
arrugas que hayan surgido en el proceso de lavado y secado.
Para ello, se propone un nuevo algoritmo de planchado, que
utiliza un descriptor de arrugas desarrollado en este trabajo para
localizar las arrugas más prominentes y generar un plan de
planchado acorde a las condiciones de la prenda. A diferencia
de otros métodos existentes, este método puede aplicarse en un
entorno doméstico, ya que no requiere de un contol preciso de
las condiciones de iluminación. Además, es capaz de usar las
mismas herramientas de planchado que usaría una persona sin
necesidad de realizar modificaciones a las mismas, a través de
un controlador que usa realimentación de fuerza para aplicar
una presión constante durante el planchado.
El último paso al hacer la colada es doblar la prenda para
almacenarla. Un aspecto importante al doblar prendas es ejecutar
cada uno de los dobleces necesarios con precisión, ya que
cada error o desfase cometido en un doblez se acumula cuando
la secuencia de doblado está formada por varios dobleces
consecutivos. Para llevar a cabo estos dobleces con la precisión
requerida, se propone un controlador basado en una red neuronal,
que utiliza realimentación visual de la forma de la prenda
durante cada operación de doblado. Esta realimentación es obtenida
a través de una red neuronal profunda entrenada con
un conjunto de entrenamiento sintético, que permite estimar
la forma en 3D de la parte a doblar a través de una imagen
monocular de la misma.
Todos los métodos descritos en esta tesis han sido validados
experimentalmente con éxito en diversas plataformas robóticas,
incluyendo un robot humanoide.Programa de Doctorado en Ingeniería Eléctrica, Electrónica y Automática por la Universidad Carlos III de MadridPresidente: Abderrahmane Kheddar.- Secretario: Ramón Ignacio Barber Castaño.- Vocal: Karinne Ramírez-Amar
Recognising the Clothing Categories from Free-Configuration Using Gaussian-Process-Based Interactive Perception
In this paper, we propose a Gaussian Process- based interactive perception approach for recognising highly- wrinkled clothes. We have integrated this recognition method within a clothes sorting pipeline for the pre-washing stage of an autonomous laundering process. Our approach differs from reported clothing manipulation approaches by allowing the robot to update its perception confidence via numerous interactions with the garments. The classifiers predominantly reported in clothing perception (e.g. SVM, Random Forest) studies do not provide true classification probabilities, due to their inherent structure. In contrast, probabilistic classifiers (of which the Gaussian Process is a popular example) are able to provide predictive probabilities. In our approach, we employ a multi-class Gaussian Process classification using the Laplace approximation for posterior inference and optimising hyper-parameters via marginal likelihood maximisation. Our experimental results show that our approach is able to recognise unknown garments from highly-occluded and wrinkled con- figurations and demonstrates a substantial improvement over non-interactive perception approaches
Pointcloud-based Identification of Optimal Grasping Poses for Cloth-like Deformable Objects
In this paper, the problem of identifying optimal grasping poses for cloth-like deformable objects is addressed by means of a four-steps algorithm performing the processing of the data coming from a 3D camera. The first step segments the source pointcloud, while the second step implements a wrinkledness measure able to robustly detect graspable regions of a cloth. In the third step the identification of each individual wrinkle is accomplished by fitting a piecewise curve. Finally, in the fourth step, a target grasping pose for each detected wrinkle is estimated. Compared to deep learning approaches where the availability of a good quality dataset or trained model is necessary, our general algorithm can find employment in very different scenarios with minor parameters tweaking. Results showing the application of our method to the clothes bin picking task are presented
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