scholarly journals Development of Visual Servoing-Based Autonomous Docking Capabilities in a Heterogeneous Swarm of Marine Robots

2020 ◽  
Vol 10 (20) ◽  
pp. 7124
Author(s):  
Anja Babić ◽  
Filip Mandić ◽  
Nikola Mišković
Keyword(s):  
Visual Servoing ◽  
Real Life ◽  
Sensor Nodes ◽  
Design Development ◽  
Level Control ◽  
Image Processing Algorithm ◽  
Control Structures ◽  
Robotic Swarm ◽  
High Level

This paper describes the design, development, and testing of both hardware and software for a visual servoing-based system that enables agents within a heterogeneous marine robotic swarm to share energy. The goal of this system is prolonging the active operational time of the swarm as a whole, allowing it to perform long-term environmental monitoring and data collection missions. The implementation presented in the paper features an over-actuated autonomous surface platform docking up to four floating sensor nodes at a time and replenishing their batteries using wireless inductive charging. Mechanical solutions for each robot segment related to the docking procedure are presented, along with pertinent high-level and low-level control structures. A node featuring an extended Kalman filter and additional heuristics is used to fuse measurements from a neural network trained for object detection and a hue thresholding image processing algorithm, in order to track the docking target and achieve visual servoing. Finally, experimental results in both a controlled environment and challenging conditions on-site are presented. Once deployed, the developed system successfully enables the approach and docking of the designated target, showing its feasibility in different real-life conditions.

scholarly journals A Heterogeneous Robotic Swarm for Long-Term Monitoring of Marine Environments

2019 ◽  
Vol 9 (7) ◽  
pp. 1388 ◽  
Author(s):  
Ivan Lončar ◽  
Anja Babić ◽  
Barbara Arbanas ◽  
Goran Vasiljević ◽  
Tamara Petrović ◽  
...  
Keyword(s):  
Acoustic Communication ◽  
Data Exchange ◽  
Real Life ◽  
Sensor Nodes ◽  
Underwater Communication ◽  
Underwater Robots ◽  
Robotic Swarm ◽  
Long Term Monitoring ◽  
Term Monitoring

This paper describes an underwater acoustic sensor network consisting of a heterogeneous robotic swarm used for long-term monitoring of underwater environments. The swarm consists of a large number of underwater robots acting as sensor nodes with limited movement capabilities, and a few surface robots aiding them in accomplishing underwater monitoring scenarios. Main interactions between two types of robots include underwater sensor deployment and relocation, energy and data exchange, and acoustic localisation aiding. Hardware capabilities of each vehicle are described in detail. Inter-agent communication is split into two layers: surface and underwater communication. Surface communication utilises wireless communication using WiFi routers configured for decentralised routing. Underwater communication mainly uses acoustic communication which, when used within a large swarm, poses a challenging task because of high probability of interference and data loss. The acoustic communication protocol used to prevent these issues is presented in detail. Finally, more complex functionalities of the robotic swarm are presented, including several results from real-life experiments.

Alchemical Transformations? Fictions of the Nuclear State after 1989

2016 ◽  
Author(s):  
Daniel Grausam
Keyword(s):  
Thomas Pynchon ◽  
Real Life ◽  
Nuclear Age ◽  
Nuclear Site ◽  
The Us ◽  
Aesthetic Practice ◽  
Plutonium Production ◽  
High Level ◽  
The Cold War

James Flint’s novel The Book of Ash (2004) is a book concerned with the toxic legacy of the Cold War and the literary challenge of representing the security state inherited from Thomas Pynchon. The plot concerns Cooper James, a computer programmer employed by the US military at Featherbrooks, an RAF outpost in North Yorkshire, and his search for the truth about his father. The figure of the father is inspired by the real-life American sculptor James Acord (1944–2011), the only private citizen in the world licensed to own and handle high-level radioactive materials. In 1989 Acord moved close to Hanford, site of US plutonium production and the most polluted nuclear site in the US, where he sought to create something like a nuclear Stonehenge as a long-term memorial to the nuclear age, and to develop artistic practices for transmuting radioactive waste into less harmful substances. Acord imagined his own aesthetic practice to be a kind of alchemy, and The Book of Ash is precisely in this same style, making alchemical transformation a literary subject but also a literary technique: it is a radioactive novel in its subject matter and the way it transmutes novelistic style and content over time.

High Level Definition of Event-Based Applications for Pervasive Systems

2011 ◽  
pp. 128-172
Author(s):  
Steffen Ortmann ◽  
Michael Maaser ◽  
Peter Langendoerfer
Keyword(s):  
Energy Efficiency ◽  
Real Life ◽  
Ease Of Use ◽  
Design Flow ◽  
Sensor Nodes ◽  
Definition Of ◽  
High Level ◽  
Event Based ◽  
New Applications

Within pervasive intelligent environments, Wireless Sensor Networks (WSNs) will surround and serve us at any place and any time. A proper usability is considered essential for WSNs supporting real life applications. With this chapter, we aim at ease of use for specifying new applications that have to autonomously cope with expected and unexpected heterogeneity, sudden failures, and energy efficiency. Starting with general design criteria for applications in WSNs, we created a user-centric design flow for pervasive applications. The design flow provides very high abstraction and user guidance to refrain the user from implementation-, deployment- and hardware-details including heterogeneity of the available sensor nodes. Automatic event configuration is accomplished by using a flexible Event Specification Language (ESL) and Event Decision Trees (EDTs) for distributed detection and determination of real world phenomena. EDTs autonomously adapt to heterogeneous availability of sensing capabilities by pruning and subscription to other nodes for missing information. We present one of numerous simulated scenarios proving the robustness and energy efficiency with regard to the required network communications. From these, we learned how to deduce appropriate bounds for configuration of collaboration region and leasing time by asking for expected properties of the phenomena to be detected.

Medical Simulation as an Instructional Tool in Health Education

2017 ◽  
pp. 101-132 ◽  
Author(s):  
Anna Lerant ◽  
Oliver Jason Bates ◽  
Michael G. Holder ◽  
Jeffrey D. Orledge ◽  
Robin (Rob) W. Rockhold ◽  
...  
Keyword(s):  
Real Life ◽  
Design System ◽  
Psychomotor Skills ◽  
Design Development ◽  
Planning Time ◽  
Analysis And Design ◽  
Cognitive Component ◽  
Worked Example ◽  
Analysis Design ◽  
High Level

The purpose of this chapter is to provide a background and a worked example of using the Instructional Design System (ISD) as applied to a complex real life example. Specifically, the authors demonstrate the use of ADDIE (Analysis, Design, Development, Implementation, and Evaluation) for building the instruction curriculum of the skills of intubation. The majority of the planning time should be spent on the Needs Analysis and Design. The Learning Objectives, prepared during the Design phase, should be written as Objective Observable Behaviors, which can then serve as the assessments for Evaluation. The content includes two examples of the application of ADDIE: firstly a task that requires a large cognitive component and where simulators and mannequins are readily available. Secondly, a task that requires a high level of psychomotor skills where suitably realistic mannequins are not available, and virtual reality needs to be used as an additional educational modality.

Design and development of a durable series elastic actuator with an optimized spring topology

2021 ◽  
pp. 095440622110203
Author(s):  
Mehmet C Yildirim ◽  
Polat Sendur ◽  
Ahmet Talha Kansizoglu ◽  
Umut Uras ◽  
Onur Bilgin ◽  
...  
Keyword(s):  
Real Life ◽  
Integrated Design ◽  
Torque Control ◽  
Test Machine ◽  
Design Development ◽  
Test Procedures ◽  
Testing Procedures ◽  
Series Elastic Actuator ◽  
Series Elastic

This paper aims to present the integrated design, development, and testing procedures for a state-of-the-art torsion-based series elastic actuator that could be reliably employed for long-term use in force-controlled robot applications. The main objective in designing the actuator was to meet weight and dimensional requirements whilst improving the long-term durability, ensuring high torque output, and containing its total weight. A four-fold design approach was implemented: (i) following recursive design-and-test procedures, an optimal torsional spring topology was unveiled with the help of SIMP (Solid Isotropic Material with Penalization) topology optimization method, (ii) the proposed spring was manufactured and multiple specimens were experimentally tested via a torsional test machine to validate linearity, loading rate response, and mechanical limits, (iii) the actuator’s thermal response was experimentally scrutinized to ensure that the generated heat was dissipated for long-term use, and (iv) the fatigue life of the spring was computed with the help of real-life experiment data. Having concluded the development and verification procedures, two different versions of the actuator were built, and preliminary torque control experiments were conducted. In conclusion, favorable torque tracking with a bandwidth of 19 Hz was achieved while peak-to-peak torque input was 20 Nm.

Vivid Imagers Are Better at Detecting Salient Changes

2006 ◽  
Vol 27 (4) ◽  
pp. 218-228 ◽  
Author(s):  
Paul Rodway ◽  
Karen Gillies ◽  
Astrid Schepman
Keyword(s):  
Individual Differences ◽  
Change Detection ◽  
Visual Imagery ◽  
Detection Task ◽  
Level Of Detail ◽  
Detection Accuracy ◽  
Change Detection Task ◽  
Term Change ◽  
High Level

This study examined whether individual differences in the vividness of visual imagery influenced performance on a novel long-term change detection task. Participants were presented with a sequence of pictures, with each picture and its title displayed for 17  s, and then presented with changed or unchanged versions of those pictures and asked to detect whether the picture had been changed. Cuing the retrieval of the picture's image, by presenting the picture's title before the arrival of the changed picture, facilitated change detection accuracy. This suggests that the retrieval of the picture's representation immunizes it against overwriting by the arrival of the changed picture. The high and low vividness participants did not differ in overall levels of change detection accuracy. However, in replication of Gur and Hilgard (1975) , high vividness participants were significantly more accurate at detecting salient changes to pictures compared to low vividness participants. The results suggest that vivid images are not characterised by a high level of detail and that vivid imagery enhances memory for the salient aspects of a scene but not all of the details of a scene. Possible causes of this difference, and how they may lead to an understanding of individual differences in change detection, are considered.

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