Control System Design for a Ducted-Fan Unmanned Aerial Vehicle Using Linear Quadratic Tracker

Tracking control system based on linear quadratic (LQ) tracker is designed for a ducted-fan unmanned aerial vehicle (UAV) under full flight envelope including hover, transition, and cruise modes. To design the LQ tracker, a system matrix is augmented with a tracking error term. Then the control input can be calculated to solve a single Riccati equation, but the steady-state errors might still remain in this control system. In order to reduce the steady-state errors, a linear quadratic tracker with integrator (LQTI) is designed to add an integral term of tracking state in the state vector. Then the performance of the proposed controller is verified through waypoint navigation simulation under wind disturbance

磁気トンネル接合素子の微細加工プロセスダメージ現象の解析と酸化後処理によるその回復技術に関する研究

要約のみTohoku University遠藤哲郎課

Fully Geometric Panoramic Localization

We introduce a lightweight and accurate localization method that only utilizes the geometry of 2D-3D lines. Given a pre-captured 3D map, our approach localizes a panorama image, taking advantage of the holistic 360 view. The system mitigates potential privacy breaches or domain discrepancies by avoiding trained or hand-crafted visual descriptors. However, as lines alone can be ambiguous, we express distinctive yet compact spatial contexts from relationships between lines, namely the dominant directions of parallel lines and the intersection between non-parallel lines. The resulting representations are efficient in processing time and memory compared to conventional visual descriptor-based methods. Given the groups of dominant line directions and their intersections, we accelerate the search process to test thousands of pose candidates in less than a millisecond without sacrificing accuracy. We empirically show that the proposed 2D-3D matching can localize panoramas for challenging scenes with similar structures, dramatic domain shifts or illumination changes. Our fully geometric approach does not involve extensive parameter tuning or neural network training, making it a practical algorithm that can be readily deployed in the real world. Project page including the code is available through this link: https://82magnolia.github.io/fgpl/.Comment: Accepted to CVPR 202

Design and Implementation of a Wireless Charging-Based Cardiac Monitoring System Focused on Temperature Reduction and Robust Power Transfer Efficiency

Wireless power transfer systems are increasingly used as a means of charging implantable medical devices. However, the heat or thermal radiation from the wireless power transfer system can be harmful to biological tissue. In this research, we designed and implemented a wireless power transfer system-based implantable medical device with low thermal radiation, achieving 44.5% coil-to-coil efficiency. To suppress thermal radiation from the transmitting coil during charging, we minimized the ESR value of the transmitting coil. To increase power transfer efficiency, a ferrite film was applied on the receiving part. Based on analyses, we fabricated a cardiac monitoring system with dimensions of 17 x 24 x 8 mm(3) and implanted it in a rat. We confirmed that the temperature of the wireless charging device increased by only 2 degrees C during the 70 min charging, which makes it safe enough to use as an implantable medical device charging system.11Ysciescopu

Visual Style Prompting with Swapping Self-Attention

In the evolving domain of text-to-image generation, diffusion models have emerged as powerful tools in content creation. Despite their remarkable capability, existing models still face challenges in achieving controlled generation with a consistent style, requiring costly fine-tuning or often inadequately transferring the visual elements due to content leakage. To address these challenges, we propose a novel approach, \ours, to produce a diverse range of images while maintaining specific style elements and nuances. During the denoising process, we keep the query from original features while swapping the key and value with those from reference features in the late self-attention layers. This approach allows for the visual style prompting without any fine-tuning, ensuring that generated images maintain a faithful style. Through extensive evaluation across various styles and text prompts, our method demonstrates superiority over existing approaches, best reflecting the style of the references and ensuring that resulting images match the text prompts most accurately. Our project page is available https://curryjung.github.io/VisualStylePrompt/

Cooperative control for a flight array of UAVs and an application in radar jamming

This paper proposes a flight array system and an integrated approach to cope with its operational issues raised in mission-planning level (i.e., task allocation) and control level (i.e., control allocation). The proposed flight array system consists of multiple ducted-fan UAVs that can assemble with each other to fly together, as well as dissemble themselves to fly individually for accomplishing a given mission. To address the task allocation problem, a game-theoretical framework is developed. This framework enables agents to converge into an agreed task allocation in a decentralised and scalable manner, while guaranteeing a certain level of global optimality. In addition, this paper suggests a cooperative control scheme based on sliding mode control and weighted pseudo-inverse techniques so that the system’s non-linearity and control allocation issue are effectively handled. As a proof-of-concept, a prototype simulation program is developed and validated in a cooperative jamming mission. The numerical simulations manifest the feasibility of effectiveness of the proposed approach

An integrated decision-making framework of a heterogeneous aerial robotic swarm for cooperative tasks with minimum requirements

Given a cooperative mission consisting of multiple tasks spatially distributed, an aerial robotic swarm’s decision-making issues include team formation, team-to-task assignment, agent-to-work-position assignment and trajectory optimisation with collision avoidance. The problem becomes even more complicated when involving heterogeneous agents, tasks’ minimum requirements and fair allocation. This paper formulates all the combined issues as an optimisation problem and then proposes an integrated framework that addresses the problem in a decentralised fashion. We approximate and decouple the complex original problem into three subproblems (i.e. coalition formation, position allocation and path planning), which are sequentially addressed by three different proposed modules. The coalition formation module based on game theories deals with a max-min problem, the objective of which is to partition the agents into disjoint task-specific teams in a way that balances the agents’ work resources in proportion to the task’s minimum workload requirements. For agents assigned to the same task, given reasonable assumptions, the position allocation subproblem can be efficiently addressed in terms of computational complexity. For the trajectory optimisation, we utilise a Model Predictive Control and Sequential Convex Programming algorithm, which reduces the size of the problem so that the agents can generate collision-free trajectories on a real-time basis. As a proof of concept, we implement the framework into an unmanned aerial vehicle swarm’s cooperative stand-in jamming mission scenario and show its feasibility, fault tolerance and near-optimality based on numerical experiment

Binary particle swarm optimized 2 × 2 power splitters in a standard foundry silicon photonic platform

Compact power splitters designed ab initio using binary particle swarm optimization in a 2D mesh for a standard foundry silicon photonic platform are studied. Designs with a 4.8  μm×4.8  μm footprint composed of 200  nm×200  nm and 100  nm×100  nm cells are demonstrated. Despite not respecting design rules, the design with the smaller cells had lower insertion losses and broader bandwidth and showed consistent behavior across the wafer. Deviations between design and experiments point to the need for further investigations of the minimum feature dimensions

Photo-induced charge carrier dynamics in a semiconductor-based ion trap investigated via motion-sensitive qubit transitions

Ion trap systems built upon microfabricated chips have emerged as a promising platform for quantum computing to achieve reproducible and scalable structures. However, photo-induced charging of materials in such chips can generate undesired stray electric fields that disrupt the quantum state of the ion, limiting high-fidelity quantum control essential for practical quantum computing. While crude understanding of the phenomena has been gained heuristically over the past years, explanations for the microscopic mechanism of photo-generated charge carrier dynamics remains largely elusive. Here, we present a photo-induced charging model for semiconductors, whose verification is enabled by a systematic interaction between trapped ions and photo-induced stray fields from exposed silicon surfaces in our chip. We use motion-sensitive qubit transitions to directly characterize the stray field and analyze its effect on the quantum dynamics of the trapped ion. In contrast to incoherent errors arising from the thermal motion of the ion, coherent errors are induced by the stray field, whose effect is significantly imprinted during the quantum control of the ion. These errors are investigated in depth and methods to mitigate them are discussed. Finally, we extend the implications of our study to other photo-induced charging mechanisms prevalent in ion traps.Comment: 27 pages, 11 figure

Preclinical Analysis of Irreversible Electroporation on Rat Liver Tissues Using a Microfabricated Electroporator

A microfabricated electroporator (MFE) for the irreversible electroporation (IRE) of tissues has been developed by miniaturizing a clinical electroporator with a two-needle array while keeping the same electric field strength distribution. Since IRE was brought to special attention as one of the local tissue ablation techniques to treat tumors, many preclinical studies have been conducted to investigate the efficacy of IRE on animal tissues. However, some technical difficulties have been frequently encountered due to the macroscale dimension of clinical electroporators, particularly in experiments on small animal models such as the mouse or rat. Here, the MFE was proposed to solve the associated problems, resulting in time-and cost-effective experimental procedures. With the developed MFE, the effect of IRE on rat liver tissues was analyzed with time by immunohistological stainings and electrical measurement, and the experimental results were compared with those operated with the corresponding real-scale clinical electroporator.Choi YS, 2009, ANAL CHEM, V81, P3517, DOI 10.1021/ac900055rMaor E, 2009, PLOS ONE, V4, DOI 10.1371/journal.pone.0004757Pavlin M, 2008, BIOELECTROCHEMISTRY, V74, P38, DOI 10.1016/j.bioelechem.2008.04.016Sersa G, 2008, EJSO-EUR J SURG ONC, V34, P232, DOI 10.1016/j.ejso.2007.05.016Rubinsky B, 2007, TECHNOL CANCER RES T, V6, P255Onik G, 2007, TECHNOL CANCER RES T, V6, P295Al-Sakere B, 2007, TECHNOL CANCER RES T, V6, P301Maor E, 2007, TECHNOL CANCER RES T, V6, P307Garon EB, 2007, INT J CANCER, V121, P675, DOI 10.1002/ijc.22723Esser AT, 2007, TECHNOL CANCER RES T, V6, P261Lee EW, 2007, TECHNOL CANCER RES T, V6, P287Kimelman N, 2007, TISSUE ENG, V13, P1135, DOI 10.1089/ten.2007.0096Lavee J, 2007, HEART SURG FORUM, V10, pE162, DOI 10.1532/HSF98.20061202Rubinsky B, 2007, TECHNOL CANCER RES T, V6, P37Liu L, 2006, CANCER RES, V66, P11851, DOI 10.1158/0008-5472.CAN-06-1377Marty M, 2006, EJC SUPPL, V4, P3, DOI 10.1016/j.ejcsup.2006.08.002Sersa G, 2006, EJC SUPPL, V4, P52, DOI 10.1016/j.ejcsup.2006.08.007Edd JF, 2006, IEEE T BIO-MED ENG, V53, P1409, DOI [10.1109/TBME.2006.873745, 10.1109/TMBE.2006.873745]Miller L, 2005, TECHNOL CANCER RES T, V4, P699Sel D, 2005, IEEE T BIO-MED ENG, V52, P816, DOI 10.1109/TBME.2005.845212Davalos RV, 2005, ANN BIOMED ENG, V33, P223, DOI 10.1007/s10439-005-8981-8Pliquett U, 2004, BIOELECTROCHEMISTRY, V62, P83, DOI 10.1016/j.biolechem.2003.11.001Davalos RV, 2003, BIOELECTROCHEMISTRY, V61, P99, DOI 10.1016/j.bioelechem.2003.07.001Weaver JC, 2003, IEEE T DIELECT EL IN, V10, P754, DOI 10.1109/TDEI.2003.1237325Gothelf A, 2003, CANCER TREAT REV, V29, P371, DOI 10.1016/S0305-7372(03)00073-2Gehl J, 2003, ACTA PHYSIOL SCAND, V177, P437Leu JI, 2003, J CLIN INVEST, V111, P129, DOI 10.1172/JCI200316712Deng ZS, 2001, PHYSICA A, V300, P521Ryttsen F, 2000, BIOPHYS J, V79, P1993Dev SB, 2000, IEEE T PLASMA SCI, V28, P206, DOI 10.1109/27.842905Duffy DC, 1998, ANAL CHEM, V70, P4974Boone K, 1997, J MED ENG TECHNOL, V21, P201Weaver JC, 1996, BIOELECTROCH BIOENER, V41, P135*I LAB AN RES NAT, 1996, GUID CAR US LAB ANABIDOR IG, 1993, BIOCHIM BIOPHYS ACTA, V1152, P207DILLER KR, 1992, MODELING BIOHEAT TRAMIR LM, 1991, CR ACAD SCI III-VIE, V313, P613DUCK FA, 1990, PHYS PROPERTIES ISSUKINOSITA K, 1979, BIOCHIM BIOPHYS ACTA, V554, P479PENNES HH, 1948, J APPL PHYSIOL, V1, P93