Zebrafish (Danio rerio) have emerged as a valuable animal model for neurobehavioral research, particularly in the study of anxiety-related states. This article explores the use of conceptual models to investigate stress, fear, and anxiety in zebrafish induced by bio-inspired mini-robotic fish with different components and designs. The objective is to optimize robotic biomimicry and its impact on fish welfare. Previous studies have focused on externally controlled fish models, whereas this study introduces prototypes of freely actuated swimming robots to examine interactions between a bio-inspired robot and individual zebrafish. By means of analysis of behavioral responses, certain robotic components have been identified as potential causes of anxiety in fish, which have provided insights that may be applicable to other species and future aquacultural robot designs.

Rapid prototyping techniques offer significant advantages in terms of fabrication speed, accessibility, and low cost. This study explores the use of low-cost stereolithographic resins to produce prototypes intended for underwater conditions. The objective is to evaluate the feasibility of different low-cost resin brands by identifying their water absorption percentage and their response in terms of appearance and deformation after prolonged exposure to an underwater environment. Through three different tests, the suitability of the resins and possible coatings is evaluated, allowing for obtaining data not disclosed by commercial manufacturers and indicating that there are low-cost brands that offer water absorption levels suitable for underwater use. The coefficients for water absorption at saturation begin at 3.3% in saltwater and increase for chlorinated water. Additionally, significant insights are gained regarding the use of coatings. It is found that coatings commonly applied to filament-printed prototypes are generally less suitable for parts produced through stereolithography intended for underwater applications. The most effective strategy is to avoid using coatings altogether.

Este artículo describe el desarrollo de un sistema de teleoperación alámbrica para un robot subacuático basado en ROS 2 Humble. Se implementa un nodo de control que emula dinámica de primer orden, combinando aceleración proporcional y rozamiento, y publica comandos PWM para dirigir la velocidad y el ángulo de la cámara, así como para activar un electroimán. La interfaz de usuario integra nodos de teleoperación con joystick y herramientas de visualización en tiempo real. Validamos el sistema en ensayos de diez minutos en tanque, obteniendo estabilidad direccional, un error medio de seguimiento inferior al 2 % y latencias compatibles con 20 Hz. Estos resultados sientan las bases para futuras extensiones—comunicación acústica bidireccional y simulación de alta fidelidad—que mejoren la autonomía y robustez de la teleoperación submarina.