Theory Of Wing Sections Including A Summary Of Airfoil Data

Concise deep reinforcement learning obstacle avoidance for underactuated unmanned marine vessels

The development of magnetic field sensors for biomedical applications primarily focuses on equivalent magnetic noise reduction or overall design improvement in order to make them smaller and cheaper while keeping the required values of a limit of detection. One of the cutting-edge topics today is the use of magnetic field sensors for applications such as magnetocardiography, magnetotomography, magnetomyography, magnetoneurography, or their application in point-of-care devices. This introductory review focuses on modern magnetic field sensors suitable for biomedicine applications from a physical point of view and provides an overview of recent studies in this field. Types of magnetic field sensors include direct current superconducting quantum interference devices, search coil, fluxgate, magnetoelectric, giant magneto-impedance, anisotropic/giant/tunneling magnetoresistance, optically pumped, cavity optomechanical, Hall effect, magnetoelastic, spin wave interferometry, and those based on the behavior of nitrogen-vacancy centers in the atomic lattice of diamond.

Ultrasensitive Magnetic Field Sensors for Biomedical Applications.

In this paper, a dynamic model of a wheeled mobile robotic (WMR) system with coupled control input is developed, which will increase the complexity of its tracking control with time-varying advance angle. To deal with this problem, a partial reinforcement learning neural network (PRLNN)-based tracking algorithm is proposed for the WMR systems. The main contributions of the PRLNN adaptive tracking control method is that it is the first control method to introduce the PRLNN adaptive control to the WMR system, which determines to solve the WMR tracking control with the time-varying advance angle. The critic neural network (NN) and action NN adaptive laws for the decoupled controllers are designed using the standard gradient-based adaptation method. According to the Lyapunov stability analysis theorem, the uniform ultimate boundedness of all signals in the WMR system can be guaranteed with the design parameters chose properly, and the tracking error converge to a small compact set nearby zero. A numerical simulation is presented to verify the effectiveness of the proposed control algorithm.

Adaptive Partial Reinforcement Learning Neural Network-Based Tracking Control for Wheeled Mobile Robotic Systems

Otolithic afferents with regular resting discharge respond to gravity or low frequency linear accelerations, and we term these the static or sustained otolithic system. However in the otolithic sense organs there is anatomical differentiation across the maculae and corresponding physiological differentiation. A specialized band of receptors called the striola consists of mainly type I receptors whose hair bundles are weakly tethered to the overlying otolithic membrane. The afferent neurons which form calyx synapses on type I striolar receptors have irregular resting discharge and have low thresholds to high frequency (e.g. 500Hz) bone conducted vibration and air conducted sound. High frequency sound and vibration likely causes fluid displacement which deflects the weakly tethered hair bundles of the very fast type I receptors. Irregular vestibular afferents show phase locking, similar to cochlear afferents, up to stimulus frequencies of kilohertz. We term these irregular afferents the transient system signalling dynamic otolithic stimulation. 500Hz vibration preferentially activates the otolith irregular afferents, since regular afferents are not activated at intensities used in clinical testing whereas irregular afferents have low thresholds. We show how this sustained and transient distinction applies at the vestibular nuclei. The two systems have differential response to vibration and sound, to ototoxic antibiotics, to galvanic stimulation and to natural linear acceleration, and such differential sensitivity allows probing of the two systems. 500Hz vibration which selectively activates irregular otolithic afferents results in stimulus-locked eye movements in animals and humans. The preparatory myogenic potentials for these eye movements are measured in the new clinical test of otolith function – ocular vestibular evoked myogenic potentials. We suggest 500Hz vibration may identify the contribution of the transient system to vestibular controlled responses such as vestibulo-ocular, vestibulo-spinal and vestibulo-sympathetic responses. The prospect of particular treatments targeting one or the other of the transient or sustained systems is now being realized in the clinic by the use of intratympanic gentamicin which preferentially attacks type I receptors. We suggest that it is valuable to view vestibular responses by this sustained-transient distinction.

/pdf/sustained-and-transient-vestibular-systems-a-physiological-1eus11pa4a.pdf

Sustained and Transient Vestibular Systems: A Physiological Basis for Interpreting Vestibular Function.

As the USV (Unmanned Surface Vehicles) works in offshore waters whose operating environment is complex, sonar images obtained are low-resolution, noisy and narrow overlap region, and ultimately led to the sonar image cannot be stitched or get a serious distortion after image mosaicing. In response to these problems, this paper proposes a sonar image mosaicing algorithm based on improved SIFT for USV. For sonar image registration, we applies RANSAC (RANdom Sample Consensus) algorithm to check feature points to improve the accuracy of image registration. For the problem that the distribution of original image brightness is different, this paper conducts brightness normalization algorithms for brightness adjustment. To avoid empty points in stitched image and the problem that mapping coordinates may not be an integer, this paper respectively take inverse mapping method and image interpolation algorithm to solve the problem. In order to improve the sonar image borders and edge fusion effect, this paper proposes a weighted fusion algorithm based on threshold and edge. Finally, the experiments show that the algorithm has a certain practicality.

A sonar image mosaicing algorithm based on improved SIFT for USV

A sensitive separable-type detection method based on giant magnetoimpedance effect in NiFe/Cu/NiFe/Cu/Cr films for detecting traces of magnetic beads (4.5 μm) at high frequency (> 5 MHz) was presented in this paper. A microcavity with a basement thickness of 0.3 mm was fabricated by Micro-nano carving technology, and was immobilized on the meander-shaped sensing elements for loading Dynabeads. Large resistance variations were observed in the frequency range of 30 MHz∼120 MHz by the presence of Dynabeads. This method is able to detect Dynabeads as low as 10 particles using one single giant magnetoimpedance sensor without external magnetic fields and redundant washing steps, demonstrating high sensitivity, low complexity and nondestructive characteristic.

A giant magnetoimpedance-based separable-type method for supersensitive detection of 10 magnetic beads at high frequency

The invention discloses a distributed pedestrian detection system and method based on a mobile robot platform. The system comprises the mobile robot platform and a Microsoft Kinect camera, a desktop computer and a network communication device, wherein the Microsoft Kinect camera, the desktop computer and the network communication device are carried on the mobile robot platform. The method includes the steps that various current mature detection algorithms related to pedestrians and a robot operating system (ROS) are fused, various characteristics of the pedestrians are calculated through distributed calculation nodes of the robot operating system (ROS), various calculated characteristic data are comprehensively fused, pedestrian targets can be stably tracked in the robot moving process, and then detection accuracy is improved, wherein the distributed calculation nodes mainly include the histogram of gradients ( HOG) node, the face detection node, the upper body histogram of gradients (HOG) node, the skin color detection node, the point cloud detection node and the gesture detection node. The system and method are mainly used for detection calculation of the pedestrians in images of a mobile robot, and especially for mobile robot pedestrian detection calculation so that human-machine interaction can be achieved.

Distributed pedestrian detection system and method based on mobile robot platform

This article concerns the problems of a defective depth map and limited field of view of Kinect-style RGB-D sensors. An anisotropic diffusion based hole-filling method is proposed to recover invalid depth data in the depth map. The field of view of the Kinect-style RGB-D sensor is extended by stitching depth and color images from several RGB-D sensors. By aligning the depth map with the color image, the registration data calculated by registering color images can be used to stitch depth and color images into a depth and color panoramic image concurrently in real time. Experiments show that the proposed stitching method can generate a RGB-D panorama with no invalid depth data and little distortion in real time and can be extended to incorporate more RGB-D sensors to construct even a 360° field of view panoramic RGB-D image.

https://journals.sagepub.com/doi/pdf/10.1177/1729881417695560

Real-time RGB-D image stitching using multiple Kinects for improved field of view

To figure out the limitation of enough power resource or energy supplied in Antarctic expedition, this paper presented a large-size spherical robot which can drive by internal power and wind. It consists of a 2-DOF pendulum inside the shell, rotating with transverse and longitudinal axis. Due to the non-holonomic restraint of motion, for smooth and steady control, the spherical robot is designed to finish its movement by turning and linear motion independently, and simpler through decouple method. Base on this, a dynamic model of spherical robot is developed using Lagrange, and analyzed the dynamic characteristic. Further, the hardware implementations and software system are introduced. The test result showed that rolling angular velocity and pendulum angle approach to stability with smart steering, fast rolling, and accomplish common detection mission.

Hengyu Li

Papers

A sonar image mosaicing algorithm based on improved SIFT for USV

A giant magnetoimpedance-based separable-type method for supersensitive detection of 10 magnetic beads at high frequency

Distributed pedestrian detection system and method based on mobile robot platform

Real-time RGB-D image stitching using multiple Kinects for improved field of view

Dynamic analysis and control system of spherical robot for polar region scientific research