Proceedings of the Vertical Flight Society 76th Annual Forum最新文献_第9页

Optimal Trajectory Generation for a Quadrotor Biplane Tailsitter 四旋翼双翼飞机的最优轨迹生成

Proceedings of the Vertical Flight Society 76th Annual Forum Pub Date : 2020-10-05 DOI: 10.4050/f-0076-2020-16322

Kristoff McIntosh, Sandipan Mishra, Di Zhao, Jean-Paul F. Reddinger

{"title":"Optimal Trajectory Generation for a Quadrotor Biplane Tailsitter","authors":"Kristoff McIntosh, Sandipan Mishra, Di Zhao, Jean-Paul F. Reddinger","doi":"10.4050/f-0076-2020-16322","DOIUrl":"https://doi.org/10.4050/f-0076-2020-16322","url":null,"abstract":"\u0000 This paper introduces a methodology for an optimization-based trajectory planner for the autonomous transition of a quadrotor biplane tailsitter (QRBP) between the flight modes of hover to forward flight and forward flight to hover. The trajectory planner uses a simplified first principles dynamic model of the QRBP in the formulation of a optimization problem for trajectory planning. Additional constraints on the trajectory are imposed based on physical limitations, such as available power, stall limits, among others. The cost function for the optimization problem is chosen to be the time-of-transition. The solution of this problem generates time-optimal state and input trajectories for transition. To validate the algorithm, the trajectories are tested on a flight dynamics simulation of a QRBP to demonstrate feasibility and tracking performance with an inner-loop PID feedback controller; and compared against trajectories generated from a heuristic approach. The results of the simulated tracking performance indicate the proposed trajectory planner is capable of generating feasible transition trajectories for the previously specified flight modes.\u0000","PeriodicalId":293921,"journal":{"name":"Proceedings of the Vertical Flight Society 76th Annual Forum","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134629585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Outer-Loop Control Design and Simulation Handling Qualities Assessment for a Coaxial-Compound Helicopter and Tiltrotor 同轴复合直升机-倾转旋翼机外环控制设计及仿真操纵品质评估

Proceedings of the Vertical Flight Society 76th Annual Forum Pub Date : 2020-10-05 DOI: 10.4050/f-0076-2020-16392

T. Berger, M. Tischler, J. Horn

{"title":"Outer-Loop Control Design and Simulation Handling Qualities Assessment for a Coaxial-Compound Helicopter and Tiltrotor","authors":"T. Berger, M. Tischler, J. Horn","doi":"10.4050/f-0076-2020-16392","DOIUrl":"https://doi.org/10.4050/f-0076-2020-16392","url":null,"abstract":"\u0000 This paper describes the development of full flight envelope dynamic inversion outer-loop control laws used to control airspeed and flight path for two Future Vertical Lift-relevant rotorcraft configurations - a lift offset coaxial helicopter with a pusher propeller and a tiltrotor. The outer-loop control laws for both aircraft include a control allocation scheme to account for redundant controls and reduce pilot workload. A piloted simulation experiment was conducted at the Penn State Flight Simulator facility using a series of high-speed handling qualities demonstration maneuvers to evaluate the handling qualities of the control laws. Overall, the outer-loop control laws for both coaxial-pusher and tiltrotor aircraft were assigned Level 1 handling qualities for the Break Turn and High-Speed Acceleration/Deceleration tasks, and reduced pilot workload over previously developed inner-loop control laws. The outer-loop control laws also improved performance and reduced pilot workload in a formation flying task developed for this experiment. The coaxial-pusher outer-loop control laws received borderline Level 1/Level 2 ratings for the Pitch Attitude Capture and Hold and Sum-of-Sines Tracking tasks, while the tiltrotor outer-loop control laws (with their increased value of pitch attitude dropback) received Level 2 ratings.\u0000","PeriodicalId":293921,"journal":{"name":"Proceedings of the Vertical Flight Society 76th Annual Forum","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131292655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Electric Propulsion Component Sizing for Optimal Aircraft Configuration 优化飞机结构的电力推进部件尺寸

Proceedings of the Vertical Flight Society 76th Annual Forum Pub Date : 2020-10-05 DOI: 10.4050/f-0076-2020-16413

M. R. Ricci, John Myers, B. Paden, Ryan Rahn

{"title":"Electric Propulsion Component Sizing for Optimal Aircraft Configuration","authors":"M. R. Ricci, John Myers, B. Paden, Ryan Rahn","doi":"10.4050/f-0076-2020-16413","DOIUrl":"https://doi.org/10.4050/f-0076-2020-16413","url":null,"abstract":"\u0000 LaunchPoint Electric Propulsion Solutions is developing mission-optimized electric propulsion systems. Unlike traditional aircraft development where designs are often driven by available propulsion systems, the relative simplicity of electric propulsion opens up the possibility that bespoke propulsion components may be developed and optimized for a particular vehicle configuration and mission. Electric propulsion is new to many aerospace designers and there is not yet a good body of knowledge about the performance of electric propulsion components. LaunchPoint aims to fill this gap by developing user-friendly physics-based electric propulsion models for multi-disciplinary optimization in vehicle/mission designs. To date, the existing vehicle configuration studies have largely used curve fits of existing electric propulsion components that do not accurately capture all of the relationships between motor and power electronics size, mass, efficiency, voltage, torque, and rpm and how those different motor parameters affect the overall vehicle performance. In a step toward revealing these relationships, this paper presents the design results from the coupling of detailed parametric motor and drive models with a simple eVTOL vehicle model.\u0000","PeriodicalId":293921,"journal":{"name":"Proceedings of the Vertical Flight Society 76th Annual Forum","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131500894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Guidelines for System Identification of Multirotor Vehicles with Highly Correlated Inputs 具有高度相关输入的多旋翼飞行器系统辨识导则

Proceedings of the Vertical Flight Society 76th Annual Forum Pub Date : 2020-10-05 DOI: 10.4050/f-0076-2020-16294

T. Berger, Mark J. S. Lopez, M. Tischler, Aaron Wagner

{"title":"Guidelines for System Identification of Multirotor Vehicles with Highly Correlated Inputs","authors":"T. Berger, Mark J. S. Lopez, M. Tischler, Aaron Wagner","doi":"10.4050/f-0076-2020-16294","DOIUrl":"https://doi.org/10.4050/f-0076-2020-16294","url":null,"abstract":"\u0000 With the development of new over-actuated multirotor vertical lift aircraft, there is a need to identify accurate vehicle models from flight data at the individual effector level to validate physics based models or skip physics based models altogether and develop simulation models direction from the identification results. Typical frequency-domain system identification methods break down when the bare-airframe inputs are highly correlated, which is often the case when collecting system identification data for over-actuated vehicles. The Joint Input-Output Method has been previously used to mitigate the issue of input correlation, and is applied in this paper to a simulation example based on an octocopter UAS in hover. Several excitation methods are investigated to determine which are best suited for use with the Joint Input-Output Method. The identification results of the different methods with varying levels of measurement noise are presented, as are the main advantage and disadvantaged of each method. Based on these results, guidelines are provided for multirotor system identification using the Joint Input-Output Method.\u0000","PeriodicalId":293921,"journal":{"name":"Proceedings of the Vertical Flight Society 76th Annual Forum","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134267811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Holistic Life Management of Damage Tolerant Airframes 容损机身的整体寿命管理

Proceedings of the Vertical Flight Society 76th Annual Forum Pub Date : 2020-10-05 DOI: 10.4050/f-0076-2020-16311

Darryl Toni, A. Sarlashkar, Sikorsky

引用次数: 0

Rotorcraft Lubrication Optimization through Grease Sampling and Analysis 基于润滑脂采样与分析的旋翼机润滑优化

Proceedings of the Vertical Flight Society 76th Annual Forum Pub Date : 2020-10-05 DOI: 10.4050/f-0076-2020-16274

R. Wurzbach, M. Labs, Michael K. Johnson, Amrri, Timithy Singer, B. Co.

引用次数: 0

An Evaluation of Finite-State Dynamic Inflow for Usage in Design 在设计中应用的有限状态动态流的评价

Proceedings of the Vertical Flight Society 76th Annual Forum Pub Date : 2020-10-05 DOI: 10.4050/f-0076-2020-16440

J. Ho, H. Yeo

{"title":"An Evaluation of Finite-State Dynamic Inflow for Usage in Design","authors":"J. Ho, H. Yeo","doi":"10.4050/f-0076-2020-16440","DOIUrl":"https://doi.org/10.4050/f-0076-2020-16440","url":null,"abstract":"\u0000 In an effort to evaluate the accuracy of the finite-state dynamic inflow of Peters and He for use in rotor design, comparisons between dynamic inflow-based calculations and measured test data are presented for a wide variety of single rotor configurations and operating conditions. The quantities compared include rotor performance parameters, blade flap bending moments, blade airloads, and blade pitch angles. The dynamic inflow calculations are performed using the U. S. Army's Rotorcraft Comprehensive Analysis System (RCAS). Rotor performance calculations are mostly accurate prior to stall, except for rotor torque calculations from an individual blade pitch control (IBC) phase sweep. Blade airloads calculations do exhibit the correct dominant features including those from blade tip vortices, but the calculated amplitudes of the wake-induced loading are significantly less than the test data; this leads to significantly lower amplitudes in the flap bending moment response and is problematic for calculating half peak-to-peak values in conditions with significant blade-wake interactions. Blade collective and cyclic pitch angles are reasonably accurate in edgewise flight. Some practical, but not necessarily well-known, aspects of dynamic inflow are also discussed; this includes convergence characteristics with the number of inflow states and providing a formula for determining the number of inflow states.\u0000","PeriodicalId":293921,"journal":{"name":"Proceedings of the Vertical Flight Society 76th Annual Forum","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131014494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Medium-Sized Helicopter Noise Abatement Flight Test 中型直升机降噪飞行试验

Proceedings of the Vertical Flight Society 76th Annual Forum Pub Date : 2020-10-05 DOI: 10.4050/f-0076-2020-16497

Kyle A. Pascioni, Nasa, M. E. Watts, C. W. Smith, James H. Stephenson, Ccdc AvMC, Eric Greenwood

{"title":"Medium-Sized Helicopter Noise Abatement Flight Test","authors":"Kyle A. Pascioni, Nasa, M. E. Watts, C. W. Smith, James H. Stephenson, Ccdc AvMC, Eric Greenwood","doi":"10.4050/f-0076-2020-16497","DOIUrl":"https://doi.org/10.4050/f-0076-2020-16497","url":null,"abstract":"\u0000 An extensive flight test campaign was recently completed, which aims to reduce the operational noise generated by helicopters in an effort to improve community acceptance. Using a ground-based microphone array, acoustic measurements were acquired on helicopters in the medium-sized vehicle weight class over a number of flight conditions including steady level flight, steady descents, and approaches. While data were collected across four helicopters, the Leonardo AW139 and Sikorsky S-76D will be the focus of this paper. Source noise hemispheres are computed for the steady test points, but the ground noise contours measured during approach conditions cover only a small portion of the area impacted by noise because of practical constraints on the size of the deployed array. Thus, the Noise Informed Community Environment Operations Planning System (NICEOPS) in conjunction with the flight test data was used to estimate how changes in the approach procedures impact noise exposure over a larger ground area. It was found that even small longitudinal accelerations can have a substantial influence on the noise generation processes during approach and must be modeled appropriately to develop new flight procedures which minimize the acoustic impact on the ground.\u0000","PeriodicalId":293921,"journal":{"name":"Proceedings of the Vertical Flight Society 76th Annual Forum","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132387485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Explainable AI: Rotorcraft Attitude Prediction 可解释的AI:旋翼机姿态预测

Proceedings of the Vertical Flight Society 76th Annual Forum Pub Date : 2020-10-05 DOI: 10.4050/f-0076-2020-16344

Hikmat Khan, N. Bouaynaya, G. Rasool, C. Johnson

{"title":"Explainable AI: Rotorcraft Attitude Prediction","authors":"Hikmat Khan, N. Bouaynaya, G. Rasool, C. Johnson","doi":"10.4050/f-0076-2020-16344","DOIUrl":"https://doi.org/10.4050/f-0076-2020-16344","url":null,"abstract":"\u0000 Rotorcrafts are generally subject to a higher fatal accident rate than other segments of aviation, including commercial and general aviation. The safety improvement for rotorcrafts would directly improve the efficiency of air traffic control, since rotorcrafts operate primarily within low-level airspace; an area that is becoming increasingly complex with new entrants, such as unmanned aircraft systems and urban air mobility. The recent impact of artificial intelligence and deep learning algorithms on various aspects of our lives has led to the investigation of the application of these algorithms in the aviation domain; as it may offer a prime opportunity to enhance safety within the aviation community. In this research, we explore the efficacy, reliability, and, more importantly, the explainability of modern deep learning algorithms. We use machine learning models to predict the attitude (pitch and yaw) of rotorcrafts using video data recorded with ordinary cameras. The cameras were mounted inside the helicopter cockpit and recorded outside view through windshield continually during the flight. We train four different architectures of convolutional neural networks (CNNs), i.e., VGG16, VGG19, ResNet50, and Xception. The models achieved 90%, 91%, 88%, and 88%, respectively, average attitude prediction accuracy on the test video dataset. Furthermore, we use gradient class activation maps (grad-CAM) to ascertain the features and regions of the image that influenced the model to make a specific prediction. We show that CNNs learn to focus on similar features as human operators (pilots), i.e., the natural horizon curve. Our findings demonstrate the feasibility of using deep learning models for attitude prediction from f light videos recorded using ordinary inexpensive cameras. The proposed video analytics framework provides a cost-effective means to supplement traditional Flight Data Recorders (FDR); a technology that is often beyond the financial reach of most general aviation rotorcraft operators.\u0000","PeriodicalId":293921,"journal":{"name":"Proceedings of the Vertical Flight Society 76th Annual Forum","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132983713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Computation and Extraction of Boundary Layer Parameters from Numerical Simulations for Use in Rotor Acoustics Models 转子声学模型数值模拟边界层参数的计算与提取

Proceedings of the Vertical Flight Society 76th Annual Forum Pub Date : 2020-10-05 DOI: 10.4050/f-0076-2020-16494

M. Costenoble, J. Baeder, J. Hrynuk, Rajneesh K. Singh

{"title":"Computation and Extraction of Boundary Layer Parameters from Numerical Simulations for Use in Rotor Acoustics Models","authors":"M. Costenoble, J. Baeder, J. Hrynuk, Rajneesh K. Singh","doi":"10.4050/f-0076-2020-16494","DOIUrl":"https://doi.org/10.4050/f-0076-2020-16494","url":null,"abstract":"\u0000 Low-order rotor broadband noise models require the boundary layer, displacement, and momentum thicknesses around the rotor's component airfoils to be provided. This data is often unavailable from prior literature, and may not be accurately computed (if at all) by simplified aerodynamics codes. To obtain the boundary layer thicknesses, this study builds on an integrated and robust meshing and solution approach using HAM2D, a Navier-Stokes computational code with advanced flow transition computations. This approach using HAM2D is already used to compute airfoil performance tables, and the computation of the boundary layer thicknesses imposes negligible additional overhead. The boundary layers computed by HAM2D are validated against prior data and wind tunnel PIV measurements conducted specifically for this study. In general, HAM2D shows good agreement with both experimental data sets, particularly with the PIV measurements conducted for this study, and where HAM2D diverges from historical data, so too do the PIV measurements. A few specific points of disagreement are noted, and future work will seek to reduce these inconsistencies.\u0000","PeriodicalId":293921,"journal":{"name":"Proceedings of the Vertical Flight Society 76th Annual Forum","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131068806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0