Anthony J. Clark

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Designing a robotic fish is a challenging endeavor due to the non-linear dynamics of underwater environments. In this paper , we present an evolutionary computation approach for designing the caudal fin of a carangiform robotic fish. Evolutionary experiments are performed in a simulated environment utilizing a mathematical model to approximate the(More)
  • Pollaphat Nitithamyong, Mirosław J Skibniewski, A James Clark
  • 2006
SUMMARY: The effectiveness and usefulness of Web-based project management system (WPMS) applications in construction projects are still not yet as high as initially expected, mainly because many important factors that can greatly impact system performance are left unknown or misunderstood by most practitioners. Understanding which factors are critical for(More)
Developing complex behaviors for aquatic robots is a difficult en- gineering challenge due to the uncertainty of an underwater environment. Neuroevolution provides one method of dealing with this type of problem. Artificial neural networks discern different conditions by mapping sensory input to responses, and evolutionary computation provides a training(More)
Many robotic systems experience fluctuating dynamics during their lifetime. Variations can be attributed in part to material degradation and decay of mechanical hardware. One approach to mitigating these problems is to utilize an adaptive controller. For example, in model-free adaptive control (MFAC) a controller learns how to drive a system by continually(More)
—In this paper, we apply evolutionary multiobjective optimization to the design of a robotic fish with a flexible caudal fin. Specifically, we use the NSGA-II algorithm to discover solutions (physical dimensions, flexibility, and control parameters) that optimize both swimming performance and power efficiency. The optimization is conducted in a custom(More)
Introduction. Web-based applications are highly accessible to users, providing rich, interactive content while eliminating the need to install software locally. Previous online evolutionary demonstrations (PicBreeder [Secretan et al., 2008], Endless Forms [Clune and Lipson, 2011], Lu-dobots [Bongard et al., 2012], and BoxCar2D) have successfully(More)
The nonlinear dynamics of an aquatic environment make robotic fish behavior difficult to predict and subsequently difficult to optimize. In this paper, we present a method for optimizing robotic fish propulsion through the evolution of control patterns and caudal fin flexibility. Evolved solutions are evaluated in a physics-based simulation environment.(More)
Robotic fish accomplish swimming by deforming their bodies or other fin-like appendages. As an emerging class of embedded computing system, robotic fish are anticipated to play an important role in environmental monitoring, inspection of underwater structures, tracking of hazardous wastes and oil spills, and the study of live fish behaviors. While(More)
Adaptive controllers enable cyber-physical systems, such as autonomous robots, to manage uncertain conditions during execution. However, there is a limit to the range of conditions that can be handled by a given controller. When this limit is exceeded, a controller might fail to respond as expected, not only rendering it ineffective but possibly putting the(More)