3,419 research outputs found
DREAM Architecture: a Developmental Approach to Open-Ended Learning in Robotics
Robots are still limited to controlled conditions, that the robot designer
knows with enough details to endow the robot with the appropriate models or
behaviors. Learning algorithms add some flexibility with the ability to
discover the appropriate behavior given either some demonstrations or a reward
to guide its exploration with a reinforcement learning algorithm. Reinforcement
learning algorithms rely on the definition of state and action spaces that
define reachable behaviors. Their adaptation capability critically depends on
the representations of these spaces: small and discrete spaces result in fast
learning while large and continuous spaces are challenging and either require a
long training period or prevent the robot from converging to an appropriate
behavior. Beside the operational cycle of policy execution and the learning
cycle, which works at a slower time scale to acquire new policies, we introduce
the redescription cycle, a third cycle working at an even slower time scale to
generate or adapt the required representations to the robot, its environment
and the task. We introduce the challenges raised by this cycle and we present
DREAM (Deferred Restructuring of Experience in Autonomous Machines), a
developmental cognitive architecture to bootstrap this redescription process
stage by stage, build new state representations with appropriate motivations,
and transfer the acquired knowledge across domains or tasks or even across
robots. We describe results obtained so far with this approach and end up with
a discussion of the questions it raises in Neuroscience
Computational Theories of Curiosity-Driven Learning
What are the functions of curiosity? What are the mechanisms of
curiosity-driven learning? We approach these questions about the living using
concepts and tools from machine learning and developmental robotics. We argue
that curiosity-driven learning enables organisms to make discoveries to solve
complex problems with rare or deceptive rewards. By fostering exploration and
discovery of a diversity of behavioural skills, and ignoring these rewards,
curiosity can be efficient to bootstrap learning when there is no information,
or deceptive information, about local improvement towards these problems. We
also explain the key role of curiosity for efficient learning of world models.
We review both normative and heuristic computational frameworks used to
understand the mechanisms of curiosity in humans, conceptualizing the child as
a sense-making organism. These frameworks enable us to discuss the
bi-directional causal links between curiosity and learning, and to provide new
hypotheses about the fundamental role of curiosity in self-organizing
developmental structures through curriculum learning. We present various
developmental robotics experiments that study these mechanisms in action, both
supporting these hypotheses to understand better curiosity in humans and
opening new research avenues in machine learning and artificial intelligence.
Finally, we discuss challenges for the design of experimental paradigms for
studying curiosity in psychology and cognitive neuroscience.
Keywords: Curiosity, intrinsic motivation, lifelong learning, predictions,
world model, rewards, free-energy principle, learning progress, machine
learning, AI, developmental robotics, development, curriculum learning,
self-organization.Comment: To appear in "The New Science of Curiosity", ed. G. Gordon, Nova
Science Publisher
Generative neural data synthesis for autonomous systems
A significant number of Machine Learning methods for automation currently rely on
data-hungry training techniques. The lack of accessible training data often represents
an insurmountable obstacle, especially in the fields of robotics and automation, where
acquiring new data can be far from trivial. Additional data acquisition is not only often
expensive and time-consuming, but occasionally is not even an option. Furthermore,
the real world applications sometimes have commercial sensitivity issues associated
with the distribution of the raw data.
This doctoral thesis explores bypassing the aforementioned difficulties by synthesising new realistic and diverse datasets using the Generative Adversarial Network (GAN).
The success of this approach is demonstrated empirically through solving a variety of
case-specific data-hungry problems, via application of novel GAN-based techniques
and architectures.
Specifically, it starts with exploring the use of GANs for the realistic simulation of
the extremely high-dimensional underwater acoustic imagery for the purpose of training
both teleoperators and autonomous target recognition systems. We have developed a
method capable of generating realistic sonar data of any chosen dimension by image-translation GANs with Markov principle.
Following this, we apply GAN-based models to robot behavioural repertoire generation, that enables a robot manipulator to successfully overcome unforeseen impedances,
such as unknown sets of obstacles and random broken joints scenarios.
Finally, we consider dynamical system identification for articulated robot arms. We
show how using diversity-driven GAN models to generate exploratory trajectories can
allow dynamic parameters to be identified more efficiently and accurately than with
conventional optimisation approaches.
Together, these results show that GANs have the potential to benefit a variety of
robotics learning problems where training data is currently a bottleneck
An approach to evolve and exploit repertoires of general robot behaviours
Recent works in evolutionary robotics have shown the viability of evolution driven by behavioural novelty and diversity. These evolutionary approaches have been successfully used to generate repertoires of diverse and high-quality behaviours, instead of driving evolution towards a single, task-specific solution. Having repertoires of behaviours can enable new forms of robotic control, in which high-level controllers continually decide which behaviour to execute. To date, however, only the use of repertoires of open-loop locomotion primitives has been studied. We propose EvoRBC-II, an approach that enables the evolution of repertoires composed of general closed-loop behaviours, that can respond to the robot's sensory inputs. The evolved repertoire is then used as a basis to evolve a transparent higher-level controller that decides when and which behaviours of the repertoire to execute. Relying on experiments in a simulated domain, we show that the evolved repertoires are composed of highly diverse and useful behaviours. The same repertoire contains sufficiently diverse behaviours to solve a wide range of tasks, and the EvoRBC-II approach can yield a performance that is comparable to the standard tabula-rasa evolution. EvoRBC-II enables automatic generation of hierarchical control through a two-step evolutionary process, thus opening doors for the further exploration of the advantages that can be brought by hierarchical control.info:eu-repo/semantics/acceptedVersio
Learning to Use Chopsticks in Diverse Gripping Styles
Learning dexterous manipulation skills is a long-standing challenge in
computer graphics and robotics, especially when the task involves complex and
delicate interactions between the hands, tools and objects. In this paper, we
focus on chopsticks-based object relocation tasks, which are common yet
demanding. The key to successful chopsticks skills is steady gripping of the
sticks that also supports delicate maneuvers. We automatically discover
physically valid chopsticks holding poses by Bayesian Optimization (BO) and
Deep Reinforcement Learning (DRL), which works for multiple gripping styles and
hand morphologies without the need of example data. Given as input the
discovered gripping poses and desired objects to be moved, we build
physics-based hand controllers to accomplish relocation tasks in two stages.
First, kinematic trajectories are synthesized for the chopsticks and hand in a
motion planning stage. The key components of our motion planner include a
grasping model to select suitable chopsticks configurations for grasping the
object, and a trajectory optimization module to generate collision-free
chopsticks trajectories. Then we train physics-based hand controllers through
DRL again to track the desired kinematic trajectories produced by the motion
planner. We demonstrate the capabilities of our framework by relocating objects
of various shapes and sizes, in diverse gripping styles and holding positions
for multiple hand morphologies. Our system achieves faster learning speed and
better control robustness, when compared to vanilla systems that attempt to
learn chopstick-based skills without a gripping pose optimization module and/or
without a kinematic motion planner
Computational Theories of Curiosity-Driven Learning
International audienceWhat are the functions of curiosity? What are the mechanisms of curiosity-driven learning? We approach these questions about the living using concepts and tools from machine learning and developmental robotics. We argue that curiosity-driven learning enables organisms to make discoveries to solve complex problems with rare or deceptive rewards. By fostering exploration and discovery of a diversity of behavioural skills, and ignoring these rewards, curiosity can be efficient to bootstrap learning when there is no information, or deceptive information, about local improvement towards these problems. We also explain the key role of curiosity for efficient learning of world models. We review both normative and heuristic computational frameworks used to understand the mechanisms of curiosity in humans, conceptualizing the child as a sense-making organism. These frameworks enable us to discuss the bi-directional causal links between curiosity and learning, and to provide new hypotheses about the fundamental role of curiosity in self-organizing developmental structures through curriculum learning. We present various developmental robotics experiments that study these mechanisms in action, both supporting these hypotheses to understand better curiosity in humans and opening new research avenues in machine learning and artificial intelligence. Finally, we discuss challenges for the design of experimental paradigms for studying curiosity in psychology and cognitive neuroscience
2023 SOARS Conference Program
Program for the 2023 Showcase of Osprey Advancements in Research and Scholarship (SOARS
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