Sancho Oliveira

Dr. Sancho Oliveira

ISCTE-IUL and Instituto de Telecomunicações, Lisboa, Portugal
orcid

Research Focus & Metrics

Academic Career Length

26Years (2001-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2016 in Evolutionary Computation
Verified
Journal Article
Closed access
FSFernando Silva
Fernando Silva
MDMiguel Duarte
Miguel Duarte
LCLuís Correia
Luís Correia
Sancho OliveiraSancho Oliveira
Sancho Oliveira
Anders Lyhne ChristensenAnders Lyhne Christensen
Anders Lyhne Christensen
One of the long-term goals in evolutionary robotics is to be able to automatically synthesize controllers for real autonomous robots based only on a task specification. While a number of studies have shown the applicability of evolutionary robotics techniques for the synthesis of behavioral control, researchers have consistently been faced with a number of issues preventing the widespread adoption of evolutionary robotics for engineering purposes. In this article, we review and discuss the open issues in evolutionary robotics. First, we analyze the benefits and challenges of simulation-based evolution and subsequent deployment of controllers versus evolution on real robotic hardware. Second, we discuss specific evolutionary computation issues that have plagued evolutionary robotics: (1) the bootstrap problem, (2) deception, and (3) the role of genomic encoding and genotype-phenotype mapping in the evolution of controllers for complex tasks. Finally, we address the absence of standard research practices in the field. We also discuss promising avenues of research. Our underlying motivation is the reduction of the current gap between evolutionary robotics and mainstream robotics, and the establishment of evolutionary robotics as a canonical approach for the engineering of autonomous robots.

21 March 2016 in PLOS ONE
Verified
Journal Article
Open access
PDF file
MDMiguel Duarte
Miguel Duarte
VCVasco Costa
Vasco Costa
JGJorge Gomes
Jorge Gomes
TRTiago Rodrigues
Tiago Rodrigues
FSFernando Silva
Fernando Silva
Anders Lyhne ChristensenAnders Lyhne Christensen
Anders Lyhne Christensen
Swarm robotics is a promising approach for the coordination of large numbers of robots. While previous studies have shown that evolutionary robotics techniques can be applied to obtain robust and efficient self-organized behaviors for robot swarms, most studies have been conducted in simulation, and the few that have been conducted on real robots have been confined to laboratory environments. In this paper, we demonstrate for the first time a swarm robotics system with evolved control successfully operating in a real and uncontrolled environment. We evolve neural network-based controllers in simulation for canonical swarm robotics tasks, namely homing, dispersion, clustering, and monitoring. We then assess the performance of the controllers on a real swarm of up to ten aquatic surface robots. Our results show that the evolved controllers transfer successfully to real robots and achieve a performance similar to the performance obtained in simulation. We validate that the evolved controllers display key properties of swarm intelligence-based control, namely scalability, flexibility, and robustness on the real swarm. We conclude with a proof-of-concept experiment in which the swarm performs a complete environmental monitoring task by combining multiple evolved controllers.

30 June 2017 in IEEE Transactions on Evolutionary Computation
Verified
Journal Article
Closed access
MDMiguel Duarte
Miguel Duarte
JGJorge Gomes
Jorge Gomes
Sancho OliveiraSancho Oliveira
Sancho Oliveira
Anders Lyhne ChristensenAnders Lyhne Christensen
Anders Lyhne Christensen
The evolution of task-oriented control for robots with complex locomotor systems is currently out of reach for traditional evolutionary computation techniques, as the coordination of a high number of locomotion parameters in response to the robot's sensory inputs is extremely challenging. Evolutionary techniques have therefore mainly been applied to the optimization of specific locomotion patterns, such as forward motion. In this paper, we explore the evolutionary repertoire-based control (EvoRBC) approach, which divides the synthesis of control into two steps: 1) the evolution of a repertoire of locomotion primitives using a quality diversity algorithm and 2) the evolution of a high-level arbitrator that leverages the locomotion primitives in the repertoire to solve a given task. We comprehensively study the main components of the EvoRBC approach using a four-wheel steering robot. We then conduct a set of experiments in simulation using a hexapod robot. Our results show that EvoRBC is robust to parameter variations, and for all the robots tested, it is able to evolve controllers for a maze navigation task and significantly outperforms the traditional evolutionary robotics approach.

1 April 2016
Verified
Conference Paper
Open access
MDMiguel Duarte
Miguel Duarte
JGJorge Gomes
Jorge Gomes
VCVasco Costa
Vasco Costa
TRTiago Rodrigues
Tiago Rodrigues
FSFernando Silva
Fernando Silva
Anders Lyhne ChristensenAnders Lyhne Christensen
Anders Lyhne Christensen
Automated environmental monitoring in marine environments is currently carried out either by small-scale robotic systems, composed of one or few robots, or static sensor networks. In this paper, we propose the use of swarm robotics systems to carry out marine environmental monitoring missions. In swarm robotics systems, each individual unit is relatively simple and inexpensive. The robots rely on decentralized control and local communication, allowing the swarm to scale to hundreds of units and to cover large areas. We study the application of a swarm of aquatic robots to environmental monitoring tasks. In the first part of the study, we synthesize swarm control for a temperature monitoring mission and validate our results with a real swarm robotics system. Then, we conduct a simulation-based evaluation of the robots' performance over large areas and with large swarm sizes, and demonstrate the swarm's robustness to faults. Our results show that swarm robotics systems are suited for environmental monitoring tasks by efficiently covering a target area, allowing for redundancy in the data collection process, and tolerating individual robot faults.

7 August 2014 in Journal of Intelligent & Robotic Systems
Verified
Journal Article
Open access
PDF file
MDMiguel Duarte
Miguel Duarte
Sancho OliveiraSancho Oliveira
Sancho Oliveira
Anders Lyhne ChristensenAnders Lyhne Christensen
Anders Lyhne Christensen
We propose an approach to the synthesis of hierarchical control systems comprising both evolved and manually programmed control for autonomous robots. We recursively divide the goal task into sub-tasks until a solution can be evolved or until a solution can easily be programmed by hand. Hierarchical composition of behavior allows us to overcome the fundamental challenges that typically prevent evolutionary robotics from being applied to complex tasks: bootstrapping the evolutionary process, avoiding deception, and successfully transferring control evolved in simulation to real robotic hardware. We demonstrate the proposed approach by synthesizing control systems for two tasks whose complexity is beyond state of the art in evolutionary robotics. The first task is a rescue task in which all behaviors are evolved. The second task is a cleaning task in which evolved behaviors are combined with a manually programmed behavior that enables the robot to open doors in the environment. We demonstrate incremental transfer of evolved control from simulation to real robotic hardware, and we show how our approach allows for the reuse of behaviors in different tasks.

12 December 2024 in Applied System Innovation
Verified
Journal Article
Open access
PDF file
ECElijah Malcolm Graça do Nascimento Vera Cruz
Elijah Malcolm Graça do Nascimento Vera Cruz
Sancho OliveiraSancho Oliveira
Sancho Oliveira
ACAmerico Correia
Americo Correia
Robotic systems are increasingly being used in healthcare. These systems improve patient care both by freeing healthcare professionals from repetitive tasks and by assisting them with complex procedures. This analysis examines the development and implementation of the use of robotic systems in healthcare. It also examines the application of artificial intelligence (AI), which focuses on the autonomy of robotic systems, enabling them to perform tasks autonomously. It describes the main areas of use of robots in hospitals, gives examples of the main commercial or research robots, and analyzes the main practical and safety issues associated with the use of these systems. Using the main databases, including PubMed, IEEE Xplore, MDPI, ScienceDirect, ACM Digital Library, BioMed Central, Springer, and others, an extensive search for papers related to the topic was conducted. This resulted in 59 papers being identified as eligible for this review. The article concludes with a discussion of future research areas that will ensure the effective integration of autonomous robotic systems in healthcare.