66,024 research outputs found
Squid Speed
ME450 Capstone Design and Manufacturing Experience: Winter 2021The Woods Hole Oceanographic Institution is interested in studying the ethology of longfin squid because of their importance in the ocean ecosystem. For this purpose, they have previously developed the iTag, a reusable biologging sensor tag with an integrated inertial measurement unit and magnetometer which record the squid’s motion as it swims. Our team was assigned the task of integrating a dedicated speed sensor into the existing iTag, which would allow the tag to more accurately measure the swimming speed of the animal. Our selected tag design was required to accurately measure the flow speed around the squid while also having minimal impact on both the existing sensors and the squid’s natural behavior. Based on our sponsors’ suggestions, the team selected a speed sensor design that had previously been explored on another sensor tag, which consisted of a magnetic Hall-effect sensor and rotating turbine element. At present, we have successfully integrated the new speed sensor onto the existing iTag PCB without significant interference to the magnetometer, and have confirmed that the addition of the impeller to the exterior of the current sensor package will not significantly increase the drag of the iTag. Due to time limitations and a reduced capacity for in-person work, we have not yet been able to create a prototype of the updated iTag with a functioning impeller. However, our separate analysis of the iTag internals and external package suggest that our design would fulfil the specified requirements. We recommend that future teams interested in this subject prioritize finishing the integration of the iTag system and performing physical validation of the redesigned iTag, which we were not able to achieve during this semester. In order to physically validate the redesign, we suggest programming the Hall effect sensor switch reading, calibrating the sensor to eliminate directional bias, and using the magnetometer to determine the general direction the squid is swimming. Additionally, we also suggest waterproofing the sensors and testing the tag in water for more accurate measurements than extrapolating air readings to water. Finally, the team has identified several potential design changes to the prototype iTag, including moving the Hall sensor cavity nearer to the impeller in order to improve reading accuracy, and elongating the tag body to mitigate magnetic interference. Implementing these changes will improve the functionality of the tag to make it more suitable for our sponsor’s needs.Seth Cones, Aran Mooney, K Alex Shorter: Woods Hole Oceanographic Institution, Dept of Mechanical Engineeringhttp://deepblue.lib.umich.edu/bitstream/2027.42/167644/1/Team_28-Squid_Speed.pd
Whisking with robots from rat vibrissae to biomimetic technology for active touch
This article summarizes some of the key features of the rat vibrissal system, including the actively controlled sweeping movements of the vibrissae known as whisking, and reviews the past and ongoing research aimed at replicating some of this functionality in biomimetic robots
Device modelling for bendable piezoelectric FET-based touch sensing system
Flexible electronics is rapidly evolving towards
devices and circuits to enable numerous new applications. The
high-performance, in terms of response speed, uniformity and
reliability, remains a sticking point. The potential solutions for
high-performance related challenges bring us back to the timetested
silicon based electronics. However, the changes in the
response of silicon based devices due to bending related stresses is
a concern, especially because there are no suitable models to
predict this behavior. This also makes the circuit design a
difficult task. This paper reports advances in this direction,
through our research on bendable Piezoelectric Oxide
Semiconductor Field Effect Transistor (POSFET) based touch
sensors. The analytical model of POSFET, complimented with
Verilog-A model, is presented to describe the device behavior
under normal force in planar and stressed conditions. Further,
dynamic readout circuit compensation of POSFET devices have
been analyzed and compared with similar arrangement to reduce
the piezoresistive effect under tensile and compressive stresses.
This approach introduces a first step towards the systematic
modeling of stress induced changes in device response. This
systematic study will help realize high-performance bendable
microsystems with integrated sensors and readout circuitry on
ultra-thin chips (UTCs) needed in various applications, in
particular, the electronic skin (e-skin)
Radiation damages in CMOS image sensors: testing and hardening challenges brought by deep sub-micrometer CIS processes
This paper presents a summary of the main results we observed after several years of study on irradiated custom imagers manufactured using 0,18 µm CMOS processes dedicated to imaging. These results are compared to irradiated commercial sensor test results provided by the Jet Propulsion Laboratory to enlighten the differences between standard and pinned photodiode behaviors. Several types of energetic particles have been used (gamma rays, X-rays, protons and neutrons) to irradiate the studied devices. Both total ionizing dose (TID) and displacement damage effects are reported. The most sensitive parameter is still the dark current but some quantum eficiency and MOSFET characteristics changes were also observed at higher dose than those of interest for space applications. In all these degradations, the trench isolations play an important role. The consequences on radiation testing for space applications and radiation-hardening-by-design techniques are also discussed
A LabVIEW-based PI controller for controlling CE 105 coupled Tank System
In this paper, use of Proportional-Integral (PI) controller to monitor and control liquid level in an interconnected CE 105 model coupled tank is investigated. To achieve a system which can instantaneously and accurately control the liquid level in a coupled tank, two different PI controllers have been tested. The LabVIEW library for the PI controller is used to measure liquid levels in the coupled tank. The PI SubVI already exists in the LabVIEW library that gives reasonable performance but to get a better system performance and monitor the liquid levels more accurately another SubVI is derived from the PI controller mathematical equations. The practical results and the system performance of the second SubVI show a faster response and more accurate instantaneous data which minimises the error in the measurements to ±1 mm. Furthermore, the robustness of the controller to change in the system’s parameters is also investigated and established
Mapping Big Data into Knowledge Space with Cognitive Cyber-Infrastructure
Big data research has attracted great attention in science, technology,
industry and society. It is developing with the evolving scientific paradigm,
the fourth industrial revolution, and the transformational innovation of
technologies. However, its nature and fundamental challenge have not been
recognized, and its own methodology has not been formed. This paper explores
and answers the following questions: What is big data? What are the basic
methods for representing, managing and analyzing big data? What is the
relationship between big data and knowledge? Can we find a mapping from big
data into knowledge space? What kind of infrastructure is required to support
not only big data management and analysis but also knowledge discovery, sharing
and management? What is the relationship between big data and science paradigm?
What is the nature and fundamental challenge of big data computing? A
multi-dimensional perspective is presented toward a methodology of big data
computing.Comment: 59 page
Giant Magnetoresistive Biosensors for Time-Domain Magnetorelaxometry: A Theoretical Investigation and Progress Toward an Immunoassay.
Magnetorelaxometry (MRX) is a promising new biosensing technique for point-of-care diagnostics. Historically, magnetic sensors have been primarily used to monitor the stray field of magnetic nanoparticles bound to analytes of interest for immunoassays and flow cytometers. In MRX, the magnetic nanoparticles (MNPs) are first magnetized and then the temporal response is monitored after removing the magnetic field. This new sensing modality is insensitive to the magnetic field homogeneity making it more amenable to low-power portable applications. In this work, we systematically investigated time-domain MRX by measuring the signal dependence on the applied field, magnetization time, and magnetic core size. The extracted characteristic times varied for different magnetic MNPs, exhibiting unique magnetic signatures. We also measured the signal contribution based on the MNP location and correlated the coverage with measured signal amplitude. Lastly, we demonstrated, for the first time, a GMR-based time-domain MRX bioassay. This approach validates the feasibility of immunoassays using GMR-based MRX and provides an alternative platform for point-of-care diagnostics
An IoT-based solution for monitoring a fleet of educational buildings focusing on energy efficiency
Raising awareness among young people and changing their behaviour and habits concerning energy usage iskey to achieving sustained energy saving. Additionally, young people are very sensitive to environmental protection so raising awareness among children is much easier than with any other group of citizens. This work examinesways to create an innovative Information & Communication Technologies (ICT) ecosystem (including web-based, mobile, social and sensing elements) tailored specifically for school environments, taking into account both theusers (faculty, staff, students, parents) and school buildings, thus motivating and supporting young citizenś behavioural change to achieve greater energy efficiency. A mixture of open-source IoT hardware and proprietary platforms on the infrastructure level, are currently being utilized for monitoring a fleet of 18 educational buildings across 3 countries, comprising over 700 IoT monitoring points. Hereon presented is the system's high-level architecture, as well as several aspects of its implementation, related to the application domain of educational building monitoring and energy efficiency. The system is developed based on open-source technologies andservices in order to make it capable of providing open IT-infrastructure and support from different commercial hardware/sensor vendors as well as open-source solutions. The system presented can be used to develop and offer newapp-based solutions that can be used either for educational purposes or for managing the energy efficiency ofthebuilding. The system is replicable and adaptable to settings that may be different than the scenarios envisionedhere (e.g., targeting different climate zones), different IT infrastructures and can be easily extended to accommodate integration with other systems. The overall performance of the system is evaluated in real-world environment in terms of scalability, responsiveness and simplicity
Quantum Robot: Structure, Algorithms and Applications
A kind of brand-new robot, quantum robot, is proposed through fusing quantum
theory with robot technology. Quantum robot is essentially a complex quantum
system and it is generally composed of three fundamental parts: MQCU (multi
quantum computing units), quantum controller/actuator, and information
acquisition units. Corresponding to the system structure, several learning
control algorithms including quantum searching algorithm and quantum
reinforcement learning are presented for quantum robot. The theoretic results
show that quantum robot can reduce the complexity of O(N^2) in traditional
robot to O(N^(3/2)) using quantum searching algorithm, and the simulation
results demonstrate that quantum robot is also superior to traditional robot in
efficient learning by novel quantum reinforcement learning algorithm.
Considering the advantages of quantum robot, its some potential important
applications are also analyzed and prospected.Comment: 19 pages, 4 figures, 2 table
Space Structures: Issues in Dynamics and Control
A selective technical overview is presented on the vibration and control of large space structures, the analysis, design, and construction of which will require major technical contributions from the civil/structural, mechanical, and extended engineering communities. The immediacy of the U.S. space station makes the particular emphasis placed on large space structures and their control appropriate. The space station is but one part of the space program, and includes the lunar base, which the space station is to service. This paper attempts to summarize some of the key technical issues and hence provide a starting point for further involvement. The first half of this paper provides an introduction and overview of large space structures and their dynamics; the latter half discusses structural control, including control‐system design and nonlinearities. A crucial aspect of the large space structures problem is that dynamics and control must be considered simultaneously; the problems cannot be addressed individually and coupled as an afterthought
- …