Proceedings of the Vertical Flight Society 78th Annual Forum最新文献_第9页

Lichten Award Paper: Automated Optical Rotor Blade Tip Clearance Tracking Using Artificial Intelligence Algorithms Lichten奖论文:利用人工智能算法自动光学旋翼叶尖间隙跟踪

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17633

T. Schmidt

{"title":"Lichten Award Paper: Automated Optical Rotor Blade Tip Clearance Tracking Using Artificial Intelligence Algorithms","authors":"T. Schmidt","doi":"10.4050/f-0078-2022-17633","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17633","url":null,"abstract":"\u0000 Analytical methods used to determine weapon projectile trajectory relative to helicopter rotor blade tips during most conceivable maneuvers tend to provide insufficient safety margins to accurately define a safe firing envelope. The flight test team at Sikorsky, a Lockheed Martin Company, was given the challenging task of measuring the weaponto-rotor-blade-tip clearance during these maneuvers. The first-generation methodology was entirely manual using a flat vertical projection screen tangentially aligned with the rotor tip path plane to visualize the intersection between the weapon's projectile and blade tip path. While the first flight test program utilizing this technique was successful in its own right, by the time a second opportune flight test program was initiated, software tools had been developed to help automate the process, drastically increasing the amount of data that could be used to correlate with other aircraft state parameters. During the data processing, a training set was created that was used to build an Artificial Intelligence (AI) capable of performing the same task while bringing the processing time down from 4-5 frames per second (fps) to 130 fps. This enables real-time AI inference to be taken from digital video cameras on the helicopter and clearance measurements real-time processed and recorded to the instrumentation system or displayed for the pilot's awareness.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126408148","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

Computational Analysis of a Model Coaxial Rotor Hub Wake 某型同轴转子轮毂尾迹的计算分析

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17568

Forrest Mobley, J. Coder

{"title":"Computational Analysis of a Model Coaxial Rotor Hub Wake","authors":"Forrest Mobley, J. Coder","doi":"10.4050/f-0078-2022-17568","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17568","url":null,"abstract":"\u0000 A model counter-rotating coaxial rotor hub in free-air was simulated using computational fluid dynamics as a comparison against experimental results. The simulation is performed using NASA's OVERFLOW 2.3d Reynolds averaged Navier-Stokes solver, and flow conditions are based on experiments performed in the 12-inch diameter water tunnel at ARL Penn State. Surface forces were examined, and harmonics in this data were computed and analyzed. The turbulent wake of the rotor hub was analyzed using frequency content as well as turbulent quantities related to the production and transport of turbulent kinetic energy. The lift spectrum showed different dominant frequencies for each counter-rotating hub, and the drag spectrum showed the expected dominant frequency for both parts of the hub. Frequency content of the velocity components in the wake showed positional biases towards the advancing side of each hub, opposing the results from past analyses of similar single rotor hubs. Reynolds stresses showed similar positional biases, and were also consistently concentrated in relatively small areas within the wake. The individual wakes of the hubs did not show signs of interaction until the far wake.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124853188","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

Trailing-Edge Noise Predictions of Rotorcraft Airfoils 旋翼飞机机翼尾缘噪声预测

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17431

Hyunjune Gill, Seongkyu Lee

{"title":"Trailing-Edge Noise Predictions of Rotorcraft Airfoils","authors":"Hyunjune Gill, Seongkyu Lee","doi":"10.4050/f-0078-2022-17431","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17431","url":null,"abstract":"\u0000 This paper presents the effect of rotorcraft airfoils on turbulent boundary layer trailing-edge noise. Among the numerous airfoils available for rotocraft application, a total of eleven commonly used airfoils are selected and divided in three groups, and their corresponding trailing-edge noise is investigated. The compressible Reynolds Averaged Navier-Stokes (RANS) CFD simulation coupled with a semi-empirical wall pressure spectrum model and a physics-based far-field noise prediction theory is used to predict noise levels at varying angles of attack. In this paper, the CFD tools and the noise prediction model are first validated, and then the trailing-edge noise analyses for the eleven airfoils under the same compressible flow condition are presented. It is found that NACA 0012, VR-12, and SC-1094 R8 airfoils show low trailing-edge noise levels compared to other similar airfoils in each group. The noise characteristics from airfoils like NACA 0012 shows clear separation in the frequency range where the noise from the suction or pressure side is dominant at low and high frequencies, respectively. However, airfoils like VR-12 shows that the suction-side trailing-edge noise can still be important at high frequency at small angles of attack, thus producing a combined effect from both suction and pressure sides. Furthermore, a natural laminar flow airfoil is considered to investigate how the trailing-edge noise responds to the delayed transition locations. It is observed that the delayed transition locations reduce the low- and high frequency noise at a higher angle of attack.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122232667","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

Analysis of Handling Qualities and Power Consumption for Urban Air Mobility (UAM) eVTOL Quadrotor with Degraded Heave Disturbance Rejection and Control Response 降低升沉扰动抑制与控制响应的城市空中机动(UAM) eVTOL四旋翼操纵品质与功耗分析

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17543

Jeremy Aires, S. Withrow-Maser, Allen Ruan, Carlos A. Malpica, S. Schuet

{"title":"Analysis of Handling Qualities and Power Consumption for Urban Air Mobility (UAM) eVTOL Quadrotor with Degraded Heave Disturbance Rejection and Control Response","authors":"Jeremy Aires, S. Withrow-Maser, Allen Ruan, Carlos A. Malpica, S. Schuet","doi":"10.4050/f-0078-2022-17543","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17543","url":null,"abstract":"\u0000 A piloted handling qualities study of urban air mobility (UAM) electric vertical take-off and landing (eVTOL) quadrotors was performed utilizing the Vertical Motion Simulator (VMS) facility at NASA Ames Research Center. Rotor speed and variable pitch-controlled variants of a six-passenger conceptual design vehicle were assessed with different levels of degradation to control response and disturbance rejection bandwidth (DRB) in the heave axis. In previous work, preliminary trends across several handling quality rating categories reflected the effects of these degradations. Additionally, the impact of using different test standards and turbulence on the ratings were discussed. This paper elaborates on those results, but also provides insight into unexpected trends observed during the study including: a disharmony in attitude response, subpar ratings for the baseline Level 1 performance vehicle, and excessive drift and yaw couplings observed in a lateral reposition maneuver. Moreover, shortcomings of the handling quality scales and comparisons of power consumption among the vehicles in the various test conditions are presented.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129919951","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

Flight Characteristics of AAM/UAM-Scale Quadcopters Under Atmospheric Turbulence 大气湍流条件下AAM/ uam尺度四轴飞行器的飞行特性

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17535

M. Bahr, E. Ferede, F. Gandhi

{"title":"Flight Characteristics of AAM/UAM-Scale Quadcopters Under Atmospheric Turbulence","authors":"M. Bahr, E. Ferede, F. Gandhi","doi":"10.4050/f-0078-2022-17535","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17535","url":null,"abstract":"\u0000 The flight responses of quadcopters of various scales (50-1200 lb) are evaluated in the presence of a 20 kt turbulent headwind. Nominal flight controllers are tuned for each aircraft to meet HQ specifications, where the controllers will reject disturbances to the aircraft groundspeed, attempting to maintain zero groundspeed. Froude-scaling is performed to scale the handling qualities specifications of the smaller aircraft, utilizing the additional agility. The nominal and scaled controllers are then compared in rejecting disturbance due to the turbulent headwind. Non-linear dynamic simulations are performed to evaluate the rigid body response of each aircraft, finding that scaling the flight controllers (on aircraft less than 1200 lb) reduces the pitch and roll attitude response so that all aicraft have similar peak-to-peak values. Following scaling, the peak-to-peak roll and pitch attitudes for all four aircraft are within 0.5° and 0.4° of each other, respectively. The improvement in disturbance rejection capabilities from scaling comes at the cost of 24% increase in the RMS current, and 2% additional current margin for the 50 lb aircraft (which is the largest increase). Overall, the increase in actuator activity due to scaling the controllers is less than the current margin required for maneuvering, resulting in the motors not needing to increase in size.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134426728","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

Evaluation of Pilot Assistance Systems for Helicopter Ship Deck Landing 直升机舰甲板降落引航人辅助系统评价

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17545

A. Štrbac, Malte-Jörn Maibach, D. Greiwe, A. Kalra, A. Gardner

引用次数: 1

3D Conformal Pilot Cueing for Rotorcraft Shipboard Landings: On-Demand Trajectory Generation used with a Flight Path Marker Cue 3D保形飞行员提示旋翼飞机舰载着陆:按需轨迹生成使用的飞行路径标记提示

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17507

R. Walters, Mahmoud A. Hayajnh, K. Feigh, J. Prasad

引用次数: 0

Rotorcraft Propulsion System Hybridization for Enhanced Safety and Performance 用于增强安全性和性能的旋翼飞机推进系统杂交

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17609

P. Giannola, Gerry McCann, J. Ho, M. Chan

{"title":"Rotorcraft Propulsion System Hybridization for Enhanced Safety and Performance","authors":"P. Giannola, Gerry McCann, J. Ho, M. Chan","doi":"10.4050/f-0078-2022-17609","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17609","url":null,"abstract":"\u0000 Herein, the case for hybridization will be made, primarily as a means for enhancing safety. Utilizing a case study of a popular light turbine helicopter, it will be shown that augmentation with a parallel hybrid electric system, under two critical operational failures, safety can be significantly enhanced. Conceptual design of two powertrain architectures for parallel turbine-electric hybrid propulsion systems will be examined in sufficient detail to quantify their relative impact in comparison with the existing conventional turbine-only powertrain. Initial trade studies were performed to minimize system weight, utilizing current state-of-the-art components and technology. Commercially available motors, inverters and battery systems were selected for the study. Two architectures were chosen and exercised for three operational scenarios: requirements for 2.5 minutes of emergency power, 5 minutes of emergency power and 10 minutes of emergency power at takeoff/climb power level. Relative cost and benefit are quantified by performance impacts including payload capacity impact, range, rate of climb, and high-altitude performance for the different sized battery packs required for each of the 3 emergency power durations. The key benefits are safe recovery from two serious failure modes: inoperative engine and main gearbox failure. The rough \"performance cost\" for this safety-enhancing modification is a loss of about 1/3 of the nominal useful (passenger + baggage) payload, assuming full fuel capacity operating at maximum gross takeoff weight.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132139624","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

Comprehensive Analysis and Configuration of a Control Loading Solution for a Rotary Wing Flight Simulator 旋翼飞行模拟器控制加载方案的综合分析与配置

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17573

M. Rinaldi, Pierluigi Capone, G. Guglieri

引用次数: 0

Optimization of Coaxial Rotor System for a Gun-launched Micro Air Vehicle 炮射微型飞行器同轴旋翼系统优化

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17446

H. Denton, Hao Kang, Moble Benedict

{"title":"Optimization of Coaxial Rotor System for a Gun-launched Micro Air Vehicle","authors":"H. Denton, Hao Kang, Moble Benedict","doi":"10.4050/f-0078-2022-17446","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17446","url":null,"abstract":"\u0000 The paper discusses an experimental parametric study to maximize the hover efficiency of a coaxial rotor system for a micro air vehicle (MAV) that could potentially be launched from a 40 mm grenade launcher to achieve improved mission range and endurance. Prior to testing the rotors in the coaxial configuration, isolated rotor tests were performed on acustom-built hover test stand. The rotor diameter was kept constant at 6 inches (0.015 m), and used two untwisted carbon fiber blades with rectangular planform shape. The blades utilized thin circular cambered plate airfoil sections for improved performance at low Reynolds numbers (Re ≈ 30,000). The parameters that were varied include blade thickness-to-chord ratio (t/c), chord length, pitch angle, and Reynolds number. Thickness-to-chord ratio did not have a significant impact on figure of merit below 4%. Increasing the blade chord at a constant Reynolds number and t/c significantly improved hover efficiency until a chord length of 16.6 mm (solidity, σ=0.14). Across all the cases tested, the optimal pitch angle was around 16- 17 degrees. The optimal rotor from the isolated rotor experiments was used as the baseline rotor for coaxial rotor testing where the effect of vertical rotor separation was investigated with the same blade pitch angle for upper and lower rotors. Overall, the rotor separation had negligible effect on the performance of the upper and lower rotors for a separation distance range from 0.5R to 2R. The highest figure of merit obtained for the coaxial rotor was around 0.55 at Re = 30,000. Across all the vertical separations and disk loading the torque-balanced coaxial rotor system produced almost 1.5 times the thrust of an isolated rotor, which was set at the same pitch angle.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114586962","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