Aquatic Robots Research Articles

Spatial memory training in a citizen science context

Memory deficit is one of the primary effects of intellectual disability, and has a great impact on daily life. Here, we propose a novel spatial memory training system based on a citizen science virtual environment, in which users navigate an aquatic robot in a polluted canal and identify specific objects from images acquired by the robot. A portable low-cost electroencephalography device is utilized to enhance the degree of interactivity and enable real-time estimation of the affective state of the user. We involved a cohort of 60 healthy adult subjects to evaluate users' interest, memory performance, and affective variables as a function of navigation modality (active versus passive) and interface (a traditional computer mouse versus the headset). Despite offering a higher level of difficulty, the headset was preferred over a traditional mouse control by the users, whose spatial memory performance did not vary with the navigation modality or the interface. Active navigation was found to lead to a higher level of engagement, as measured by the headset. These findings suggest the possibility of a new, effective, and entertaining form of intellectual rehabilitation with potential impact on fetal alcohol syndrome.

小型水中ロボットおよび水上パーソナルビークル

小型水中ロボットおよび水上パーソナルビークル

Toward Energetically Autonomous Foraging Soft Robots

Abstract A significant goal of robotics is to develop autonomous machines, capable of independent and collective operation free from human assistance. To operate with complete autonomy robots must be capable of independent movement and total energy self-sufficiency. We present the design of a soft robotic mouth and artificial stomach for aquatic robots that will allow them to feed on biomatter in their surrounding environment. The robot is powered by electrical energy generated through bacterial respiration within a microbial fuel cell (MFC) stomach, and harvested using state-of-the-art voltage step-up electronics. Through innovative exploitation of compliant, biomimetic actuation, the soft robotic feeding mechanism enables the connection of multiple MFC stomachs in series configuration in an aquatic environment, previously a significant challenge. We investigate how a similar soft robotic feeding mechanism could be driven by electroactive polymer artificial muscles from the same bioenergy supply. This wo...

Dynamic Modeling and PID Control of an Underwater Robot Based on the Hardware-in-the-Loop Method

In this paper, the validation of the mathematical model for an aquatic robot is presented, by implementing it in MATLAB´s Simulink toolbox to evaluate the system’s natural behavior and then running it on a dSPACE card. Subsequently, a PID control for the robot’s depth, which is programmed, compiled and runned on the Fox Board G20 embedded system, will be designed, in order to apply the “Hardware-in-the-loop” simulation methodology and test the Fox Board as the simulated plant’s controller. For this, the dSPACE card is physically connected to the embebbed system through a RS232 communication protocol, where the data used for simulating the operation of sensors and actuators that make up the robot, are sent and received.

Energy-Efficient Aquatic Environment Monitoring Using Smartphone-Based Robots

Monitoring aquatic environment is of great interest to the ecosystem, marine life, and human health. This article presents the design and implementation of Samba—an aquatic surveillance robot that integrates an off-the-shelf Android smartphone and a robotic fish to monitor harmful aquatic processes such as oil spills and harmful algal blooms. Using the built-in camera of the smartphone, Samba can detect spatially dispersed aquatic processes in dynamic and complex environment. To reduce the excessive false alarms caused by the nonwater area (e.g., trees on the shore), Samba segments the captured images and performs target detection in the identified water area only. However, a major challenge in the design of Samba is the high energy consumption resulted from continuous image segmentation. We propose a novel approach that leverages the power-efficient inertial sensors on smartphones to assist image processing. In particular, based on the learned mapping models between inertial and visual features, Samba uses real-time inertial sensor readings to estimate the visual features that guide image segmentation, significantly reducing the energy consumption and computation overhead. Samba also features a set of lightweight and robust computer vision algorithms, which detect harmful aquatic processes based on their distinctive color features. Last, Samba employs a feedback-based rotation control algorithm to adapt to spatiotemporal development of the target aquatic process. We have implemented a Samba prototype and evaluated it through extensive field experiments, lab experiments, and trace-driven simulations. The results show that Samba can achieve a 94% detection rate, a 5% false alarm rate, and a lifetime up to nearly 2 months.

Evolution of Collective Behaviors for a Real Swarm of Aquatic Surface Robots.

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.

膝関節伸展が可能な生体筋駆動型遊泳カエルロボットの開発

膝関節伸展が可能な生体筋駆動型遊泳カエルロボットの開発

Design of Robotic Fish for Aquatic Environment Monitoring

In this paper, smartphone based aquatic debris monitoring robot design is proposed and discussed. Regularly monitoring aquatic waste or debris is of more interest to the environments, aquatic life, human health, and water transport. This paper presents the design of a robotic fish system that integrates an Android smartphone and a robotic fish for debris monitoring. The smartphone based aquatic robot can accurately detect debris in the presence of various environments.

Miniature and microrobots: a review of recent developments

Purpose – This paper aims to provide an insight into recent miniaturised robot developments and applications. Design/methodology/approach – Following an introduction, this article discusses the technology and applications of miniature robots and considers swarm robotics, assembly robots, flying robots and their uses in healthcare. It concludes with a brief consideration of the emerging field of nanorobotics. Findings – This shows that all manners of miniaturised terrestrial, airborne and aquatic robots are being developed, but size and weight restraints pose considerable technological challenges, such as power sources, navigation, actuation and control. Prototypes have been developed for military, assembly, medical, environmental and other applications, as well as for furthering the understanding of swarm behaviour. In the longer term, microrobots and nanorobots offer prospects to revolutionise many aspects of healthcare, such as cancer treatment. Originality/value – This study provides details of a wide-ranging selection of miniaturised robot developments.

4-H and Aquatic Robotics

4-H and Aquatic Robotics

Dynamic Control of a Pulsatile Jet Propelled Aquatic Robot

Deriving inspiration from the propulsion methods of squids, a pulsatile jet propulsion system is adopted in a robotic model. A squid-like direction control mechanism, which can direct the jet along any direction on a hemispherical work volume, is also implemented. To obtain a suitable robot velocity (v) and a propulsive efficiency (ηp) for testing this mechanism, the stroke ratio (L/D) and outlet diameter are varied and the v and the ηp of various alternatives are estimated experimentally using vision analysis. A Stroke ratio of 3.78 and an outlet diameter of 25.4 mm were found suitable and employed for testing the mechanism. When the jet is deflected by 60° in the horizontal plane, the robot rotates about its centroid, signifying excellent maneuverability. Reverse motion was also demonstrated by removing inlet valves and blocking the outlet through the direction control mechanism. The performance of the direction control mechanism indicates that the robotic model was a feasible alternative to conventional screw-propelled aquatic robots.

Control of Balloon Fish Robot Based on Traveling Wave Equation

SUMMARY Fish have excellent swimming ability underwater. Airship robots capable of performing low-speed, low-altitude flight with low energy have been investigated. Airship robots that perform “swimming in the air” in a manner similar to aquatic organisms by combining these features have been investigated and developed. The BFR (Balloon Fish Robot) is one such of type of robot. This paper deals with the simulated motion of the BFR and parameter optimization for the propulsion efficiency of an aquatic organism-like airship robot propelled by traveling waves. The controlling expression of the BFR is written as a traveling-wave equation. The equations of motion are defined by means of the controlling expression and the drag force. Comparative simulation and experimental investigation of the forward air speed of the BFR were used to evaluate its validity. The highest propulsion efficiency parameter was investigated by calculating using the experimental air speed, the maximum amplitude of the tail fin, and the traveling-wave frequency.

Environmental Monitoring Using Autonomous Aquatic Robots: Sampling Algorithms and Experiments

This brief presents a practical solution to the problem of monitoring an environmental process in a large region by a small number of robotic sensors. Optimal sampling strategies are developed, taking into account the quality of the estimated environmental field and the lifetime of the sensors. We also present experimental results for monitoring a temperature field of an outdoor swimming pool sampled by an autonomous aquatic surface robot. Simulation and experimental results are provided to validate the proposed scheme.

Aquatic Ionic-Polymer-Metal-Composite Insectile Robot With Multi-DOF Legs

Ionic polymer-metal composite (IPMC) is used in various bioinspired systems, such as fish- and tadpole-like robots swimming in water. The deflection of this smart material results from several external factors, such as water distribution and concentration. IPMC strips with a variety of water concentration on the surfaces and the surface conductivity show various deflection patterns. In this paper, IPMC strips in four initial wetness conditions (100%, 50%, 0% wet on the anode surfaces but 100% wet on the cathode surfaces, and the last one submerged in deionized water) were tested. Even without any external excitation, the strips can bend due to nonuniform water distribution. In order to understand the effects of surface conductivity in an aquatic environment, an IPMC strip with two wires connected to two distinct spots was used to demonstrate the power loss due to the surface resistance. Three types of input signals, sawtooth, sinusoidal, and square waves, were used to compare the difference between the input and output signals measured at the two spots. Thick (1 mm) IPMC strips were fabricated and employed in this study to sustain and drive the robot with sufficient forces. Finally, an aquatic walking robot (102 × 80 × 43 mm, 39 g) with six 2-degree-of-freedom (2-DOF) legs has been designed, implemented, and walked in water at the speed of 0.5 mm/s. The average power consumption is 8 W per leg. Each leg has a thigh and a shank to generate 2-DOF motions. Each set of three legs walked together as a tripod to maintain the stability in operation.

Bio-inspired aquatic robotics by untethered piezohydroelastic actuation

This paper investigates fish-like aquatic robotics using flexible bimorphs made of macro-fiber composite (MFC) piezoelectric laminates for carangiform locomotion. In addition to noiseless and efficient actuation over a range of frequencies, geometric scalability, and simple design, bimorph propulsors made of MFCs offer a balance between the actuation force and velocity response for performance enhancement in bio-inspired swimming. The experimental component of the presented work focuses on the characterization of an elastically constrained MFC bimorph propulsor for thrust generation in quiescent water as well as the development of a robotic fish prototype combining a microcontroller and a printed-circuit-board amplifier to generate high actuation voltage for untethered locomotion. From the theoretical standpoint, a distributed-parameter electroelastic model including the hydrodynamic effects and actuator dynamics is coupled with the elongated-body theory for predicting the mean thrust in quiescent water. In-air and underwater experiments are performed to verify the incorporation of hydrodynamic effects in the linear actuation regime. For electroelastically nonlinear actuation levels, experimentally obtained underwater vibration response is coupled with the elongated-body theory to predict the thrust output. The measured mean thrust levels in quiescent water (on the order of ∼10 mN) compare favorably with thrust levels of biological fish. An untethered robotic fish prototype that employs a single bimorph fin (caudal fin) for straight swimming and turning motions is developed and tested in free locomotion. A swimming speed of 0.3 body-length/second (7.5 cm s−1 swimming speed for 24.3 cm body length) is achieved at 5 Hz for a non-optimized main body-propulsor bimorph combination under a moderate actuation voltage level.

1D14 形状記憶合金を用いた魚型水中ロボット(GS3-2:生物のバイオメカニクス・ミメティクス(2))

1D14 形状記憶合金を用いた魚型水中ロボット(GS3-2:生物のバイオメカニクス・ミメティクス(2))

1A1-B05 形状記憶合金を用いた水中ロボット用ひれ構造の検討(バイオミメティクス・バイオメカトロニクス(1))

1A1-B05 形状記憶合金を用いた水中ロボット用ひれ構造の検討(バイオミメティクス・バイオメカトロニクス(1))

Manoeuvre test simulation of a teleoperated robot designed for flow measurement in natural water bodies

This article describes the simulation results of manoeuvring operations used in ships, but applied to an SA-1 teleoperated aquatic robot. The SA-1 is a type of robot designed for flow measurement in natural water bodies (rivers, lakes). A robot's dynamic stability and course stability must be guaranteed due to the different tasks assigned to it. These features can be demonstrated through the pull-out manoeuvre, the Dieudonné spiral manoeuvre, modified Kempf manoeuvre and turning circle manoeuvre. System behaviour when using such manoeuvres can be used to propose a better control system for improving robot performance or modify system design.

Robots for monitoring the environment

PurposeThis paper aims to provide a review of the role of robots for monitoring the environment.Design/methodology/approachFollowing a short introduction, this paper discusses developments in aquatic, terrestrial and airborne robots for monitoring the environment. Brief conclusions are drawn.FindingsThis shows that robots are being developed for all manner of environmental monitoring applications. Aquatic devices are attracting the greatest attention but both terrestrial and airborne robots have the potential to play an important, future role. In many instances, their deployment reflects the difficulties in or impossibility of using manual monitoring methods. A longer‐term vision of large numbers of robots conducting environmental monitoring on a routine basis is unlikely to be realised unless lower cost solutions can be developed.Originality/valueEnvironmental monitoring robots have been under development since the 1990s and this paper provides a review of recent activities.

Sink and Swim: Clues From Nature for Aquatic Robotics

Sink and Swim: Clues From Nature for Aquatic Robotics