Results 1 - 10
of
11
Encouraging behavioral diversity in evolutionary robotics: An empirical study
- Evol. Comput
, 2012
"... Evolutionary Robotics (ER) aims at automatically designing robots or controllers of robots without having to describe their inner workings. To reach this goal, ER re-searchers primarily employ phenotypes that can lead to an infinite number of robot behaviors and fitness functions that only reward th ..."
Abstract
-
Cited by 43 (6 self)
- Add to MetaCart
(Show Context)
Evolutionary Robotics (ER) aims at automatically designing robots or controllers of robots without having to describe their inner workings. To reach this goal, ER re-searchers primarily employ phenotypes that can lead to an infinite number of robot behaviors and fitness functions that only reward the achievement of the task—and not how to achieve it. These choices make ER particularly prone to premature conver-gence. To tackle this problem, several papers recently proposed to explicitly encourage the diversity of the robot behaviors, rather than the diversity of the genotypes as in classic evolutionary optimization. Such an approach avoids the need to compute distances between structures and the pitfalls of the non-injectivity of the phenotype/behavior relation; however, it also introduces new questions: how to compare behavior? should this comparison be task-specific? and what is the best way to encourage diversity in this context? In this article, we review the main published approaches to behavioral diversity and benchmark them in a common framework. We compare each approach on three differ-ent tasks and two different genotypes. Results show that fostering behavioral diver-sity substantially improves the evolutionary process in the investigated experiments, regardless of genotype or task. Among the benchmarked approaches, multi-objective methods were the most efficient and the generic, Hamming-based, behavioral distance was at least as efficient as task-specific behavioral metrics. Keywords evolutionary robotics; diversity; multi-objective evolutionary algorithm; neural net-works. 1
Harnessing digital evolution
- IEEE Comput
, 2008
"... In digital evolution, self-replicating computer programs—digital organisms—experience mutations and selective pressures, potentially producing computational systems that, like natural organisms, adapt to their environment and protect themselves from threats. Such organisms can help guide the design ..."
Abstract
-
Cited by 22 (14 self)
- Add to MetaCart
In digital evolution, self-replicating computer programs—digital organisms—experience mutations and selective pressures, potentially producing computational systems that, like natural organisms, adapt to their environment and protect themselves from threats. Such organisms can help guide the design of computer software. Nearly 150 years ago, Charles Darwin explained how evolution and natural selection transformed the earliest life forms into the rich panoply of life seen today. Scientists estimate this process has been at work on Earth for at least 3.5 billion years. But we remain at the dawn of evolution in another world: the world of computing. There, evolution helps humans solve complex problems in engineering and provides insight into the evolutionary process in nature. As computing power continues to increase, researchers
Evolving flexible joint morphologies
- In Proceedings of the 2012 ACM Genetic and Evolutionary Computing Conference
, 2012
"... ABSTRACT Transferring virtual robotic designs into physical robots has become possible with the development of 3D printers. Accurately simulating the performance of real robots in a virtual environment requires modeling a variety of conditions, including the physical composition of the robots thems ..."
Abstract
-
Cited by 5 (4 self)
- Add to MetaCart
(Show Context)
ABSTRACT Transferring virtual robotic designs into physical robots has become possible with the development of 3D printers. Accurately simulating the performance of real robots in a virtual environment requires modeling a variety of conditions, including the physical composition of the robots themselves. In this paper, we investigate how modeling material flexibility through the use of a passive joint affects the resulting arm morphology and gait of a crawling virtual robot. Results indicate that flexibility can be a beneficial characteristic of robotic morphology design while also providing insight into the benefits of modeling material properties in a simulation environment.
IMECE2009-10781 DYNAMICS-BASED DESIGN OF A SOFT ROBOT
"... ABSTRACT This paper develops a methodology for converting the results of coarse dynamic simulations into fully realized designs. In particular, we demonstrate how to convert a caterpillar-like soft-bodied robot from a lumped-parameter form into a CAD model that could be easily manufactured. To simp ..."
Abstract
- Add to MetaCart
(Show Context)
ABSTRACT This paper develops a methodology for converting the results of coarse dynamic simulations into fully realized designs. In particular, we demonstrate how to convert a caterpillar-like soft-bodied robot from a lumped-parameter form into a CAD model that could be easily manufactured. To simplify this design problem, we propose a decomposition method involving three steps. The first step groups the elements of the lumped model into segments. This segmentation simplifies the second step, where rough CAD models are automatically synthesized for each segment from the union of many prisms. In the third step, a human designer combines and smoothes these segment models to create a fullbody CAD model. This approach simplifies the development of a high degree-of-freedom soft robot by guiding the designer to a final model with an almost fully automated process.
Toward a Methodology for Systematically Generating Energy-and Materials-Efficient Concepts Using Biological Analogies
"... Energy-and materials-efficient designs are highly valued in the context of sustainable product design, but realizing products with significant changes in efficiency is a difficult task. One means to address this challenge is to use biological analogies during ideation. The use of biological analogi ..."
Abstract
- Add to MetaCart
(Show Context)
Energy-and materials-efficient designs are highly valued in the context of sustainable product design, but realizing products with significant changes in efficiency is a difficult task. One means to address this challenge is to use biological analogies during ideation. The use of biological analogies in the design process has been shown to greatly increase the novelty of concepts generated, and many authors in the bioinspired design (BID) community contend that efficiency-related benefits may be conferred as well. However, there is disagreement in the field as to when, how, and why efficiency-related benefits might arise in BIDs. This work explores these issues in-depth. A review of BID literature and an empirical study of BIDs lead to a better understanding of the types of efficiency advantages conferred by BID and set the stage for the development of tools and methods to systematically generate more energy-and materials-efficient design concepts using biological analogies.
Just Keep Swimming: Accounting for Uncertainty in Self-Modeling Aquatic Robots
"... A robust robotic system should be able to overcome unforeseen conditions, including physical damage and component failure occurring after deployment. A self-modeling system maintains an internal image of itself, which can be updated to reflect incurred damage. The robot can use this model to derive ..."
Abstract
- Add to MetaCart
(Show Context)
A robust robotic system should be able to overcome unforeseen conditions, including physical damage and component failure occurring after deployment. A self-modeling system maintains an internal image of itself, which can be updated to reflect incurred damage. The robot can use this model to derive (or evolve) new behaviors such as gaits that account for the damage. In this paper we describe an approach to self-modeling for aquatic robots. The aquatic environment presents unique challenges to the self-modeling process, including the inherent uncertainty in the robot’s orientation and configuration. We propose and evaluate two approaches to automatically infer missing contextual information, which otherwise complicates the task of developing an accurate model. We demonstrate the effectiveness of these methods on a particular aquatic robot intended for remote sensing. 1
Identification of Dynamical Structures in Artificial Brains: An Analysis of Boolean Network Controlled Robots
, 2013
"... Automatic techniques for the design of artificial computational systems, such as control programs for robots, are currently achieving increasing attention within the AI community. A prominent case is the design of artificial neural network systems by means of search techniques, such as genetic algo ..."
Abstract
- Add to MetaCart
(Show Context)
Automatic techniques for the design of artificial computational systems, such as control programs for robots, are currently achieving increasing attention within the AI community. A prominent case is the design of artificial neural network systems by means of search techniques, such as genetic algorithms. Frequently, the search calibrates not only the system parameters, but also its structure. This procedure has the advantage of reducing the bias introduced by the designer and makes it possible to explore new, innovative solutions. The drawback, though, is that the analysis of the resulting system might be extremely difficult and limited to few coarse-grained characteristics. In this paper, we consider the case of robots controlled by Boolean networks that are automatically designed by means of a training process based on local search. We propose to analyse these systems by a method that detects mesolevel dynamical structures. These structures are emerging patterns composed of elements that behave in a coherent way and loosely interact with the rest of the system. In general, this method can be used to detect functional clusters and emerging structures in nonlinear discrete dynamical systems. It is based on an extension of the notion of cluster index, which has been previously proposed by Edelman and Tononi to analyse biological neural systems. Our results show that our approach makes it possible to identify the computational core of a Boolean network which controls a robot.
Investigating Modular Coupling of Morphology and Control with Digital Muscles
"... The musculoskeletal systems of animals are governed by a complex network of neurons that define both high- and low-level control. Individual joints are manipulated by multi-ple muscles acting as effectors for both movement and sta-bilization. We previously proposed a digital muscle model (DMM), wher ..."
Abstract
- Add to MetaCart
(Show Context)
The musculoskeletal systems of animals are governed by a complex network of neurons that define both high- and low-level control. Individual joints are manipulated by multi-ple muscles acting as effectors for both movement and sta-bilization. We previously proposed a digital muscle model (DMM), where the morphological and control aspects of sim-ulated joints evolve concurrently. The resulting solutions can provide insight into the evolution of natural organisms as well as possible designs for engineered systems. In this paper, we explore the integration of this model with an arti-ficial neural network (ANN), focusing on the communication connections between the two. In the singly-connected strat-egy, a single ANN output is delivered to a joint; each con-stituent muscle responds to the signal according to an evolved function. In the individually-connected strategy, a unique ANN output is delivered to each simulated muscle. Results indicate that for low degree-of-freedom (DOF) robots, the individually-connected systems exhibit higher fitness than the singly-connnected systems. However, in larger DOF robots, the two strategies perform comparably, despite the fact that evolved ANNs for the singly-connected system are consid-erably simpler in terms of the number of connections in the network.