ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CA / Flight tests and flight safety are tightly coupled. For a given experimental test flight, the main objective to be achieved is related to the test bed and crew integrity (i.e. Bring back the test bed in one piece). Furthermore, the aircraft operational safety (i.e. continued airworthiness) relies into the accuracy of gathered information, provided by the airborne Flight Test Instrumentation (FTI) system. Typically, the FTI system includes: a data acquisition system; a transmission system; a data recorder; multiple sensors and auxiliary equipment such as Global Navigation Satellite System (GNSS) Receiver. In a specific Flight Test Campaign (FTC), such as external stores separation FTC, the associated risk is high because the non-linear and unpredicted aerodynamics couplings between the released store and the aircraft structure (e.g. wings) could lead to a catastrophic collision condition. Typically, the setup for such FTC is a big technical challenge for the instrumentation group because the determination of six degrees of freedom (6Dof) trajectory of the release store becomes mandatory. Such information could be by the means of an optical tracking system that requires the integration of two or more hi-speed hi-resolution video cameras into FTI. Unfortunately, the FTI and the Real-Time Telemetry Link (RTL) limited bandwidth imposes several restrictions for the development and implementation of a real-time application to be used at the Ground Telemetry System (GTS) for the verification of the separation safety and the validation of the test point. This paper, presents the implementation of computer vision techniques and Camshift algorithm as an approach to tracking individual track targets on the store surface which can be perform onboard and in real time or near real time. The development of the algorithm is presented as well several experimental test results that use videos frames gathered from previous FTC executed by Instituto de Pesquisas e Ensaios em Voo (Flight Test and Research Institute - IPEV). Preliminary results present satisfactory performance.

ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / In an experimental flight test campaign, the usage of a real time Ground Telemetry System (GTS) provides mandatory support for three basic essential services: a) Safety storage of Flight Tests Instrumentation (FTI) data, in the occurrence of a critical aircraft failure; b) Monitoring of critical flight safety parameters to avoid the occurrence of accidents; and c) Monitoring of selected parameters that validates all tests points. At the operational side the test ranges typically works in two phases: a) In real time where the GTS crew performs test validation and test point selection with Telemetry data; and b) In post mission where the engineering crew performs data analysis and reduction with airborne recorded data. This process is time consuming because recorded data has to be downloaded, converted to Engineering Units (EU), sliced, filtered and processed. The main reason for the usage of this less efficient process relies in the fact that the real time Telemetry data is less reliable as compared to recorded data (i.e. it contains more noise and some dropouts). With the introduction of new technologies (i.e. i-NET) the telemetry link could be very reliable, so the GTS could perform data reduction analysis immediately after the receipt of all valid tests points, while the aircraft is still flying in a quasi-real time environment. To achieve this goal the Brazilian Flight Test Group (GEEV) along with EMBRAER and with the support of Financiadora de Estudos e Projetos (FINEP) started the development of a series of Decision Aid Tools that performs data reduction analysis into the GTS in quasi-real time. This paper presents the development and the evaluation of a tool used in Air Data System Calibration Flight Tests Campaign. The application receives the Telemetry data over either a TCP/IP or a SCRAMnet Network, performs data analysis and test point validation in real time and when all points are gathered it performs the data reduction analysis and automatically creates HTML formatted tests reports. The tool evaluation was carried out with the instruction flights for the 2009 Brazilian Flight Test School (CEV). The results present a great efficiency gain for the overall Flight Test Campaign.

ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / The real time acquisition and monitoring of the aircraft trajectory parameters is essential for the safety of the flight tests campaigns held by most of the tests centers. Nowadays the us age of an airborne GPS receiver as the main sensor for these parameters has become the preferred solution for the Flight Tests Instrumentation (FTI) systems. The main problem arises when it is required a high accuracy for these measurements (e.g. air data calibration) where the solution is achieved through differential GPS techniques. The integration of this solution requires the acquisition and the correlation of the pseudorange and phase measurements for all GPS satellites in view observed by both base and rover GPS receivers. To avoid the usage of an additional uplink for the GPS differential corrections (i.e. from the base receiver to the rover), it was developed a novel solution where the GPS observables acquired by the rover receiver are merged into the FTI PCM data stream and processed in the Telemetry ground station by a Real Time GPS Navigation (GNAV) tool together with the GPS observables acquired by the base receiver. The GNAV development is divided into several phases where the accuracy for the trajectory parameters and the complexity of the solution increases. The prototype system was built and evaluated against the post-mission Ashtech PNAV® tool and the initial tests results show a satisfactory performance for the GNAV. The tests profiles are fully compliant with the Federal Aviation Administration (FAA) Advisory Circular (AC) 25-7A.

ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / External stores separation campaign is very risky therefore its preparation presents a big technical challenge for the instrumentation group. Determination of store trajectory requires the integration of two hi-speed hi-resolution video cameras into FTI. Link bandwidth precludes the development of a real-time application to be used at the Ground Telemetry System (GTS) for separation validation. To improve efficiency IPEV, with FINEP funding, is developing a system where the separation trajectory is computed on-board and in real-time. Computed parameters are merged into FTI to be processed into GTS and compared to the estimated trajectory. The proposed architecture is presented and discussed.

Les limitations d’atterrissage des hélicoptères ne sont pas valables dans l'environnement à bord d’un navire. Il n'existe aucune méthodologie approuvée de l'analyse ou de la simulation pour évaluer la compatibilité des hélicoptères-navires et préparer les essais de qualification hélicoptères-navires. Dans ce contexte, le présent travail présente le développement et l'analyse d'une méthodologie hors ligne pour déterminer les limites opérationnelles hélicoptères-navires, SHOLs, en fonction des prédictions d’un modèle de pilote humain. Pour cela, des essais pilotés par des humains sont effectués au simulateur de l’ONERA, Salon de Provence. Sur la base des résultats de ces tests, une méthodologie innovante est validée pour déterminer la limitation de la charge de travail de pilotage, à partir des mesures des déplacements des contrôles d'hélicoptère. En outre, sont validés des modifications innovantes sur un modèle de pilote humain pour pouvoir suivre les trajectoires souhaitées et fournir le même niveau d'activité aux contrôles qu'un véritable pilote. Un ensemble de critères objectifs, correspondant aux marges de sécurité, s'ajoute aux critères subjectifs, correspondant aux limitations de la charge de travail du pilote. Une routine de simulation hors ligne, appelée SholSim, est programmée pour réaliser des simulations avec le modèle pilote et vérifier l'acceptabilité des conditions de vol, selon les critères subjectifs et objectifs. Par conséquent, le présent travail présente la première estimation, dans la littérature, des SHOLs entièrement obtenus à partir d'outils hors ligne, basés uniquement sur les prédictions de modèle pilote. / Helicopter land-based limitations are not valid in the shipboard environment. There is no analytical or simulated approved methodology for evaluating shipboard helicopter compatibility issues and preparing for at-sea flight tests. In this context, the present work presents the development and analysis of an offline methodology to determine the Ship-Helicopter Operating Limitations, SHOLs, based on pilot model predictions. For this, pilot-in-the-loop simulation trials are performed at the engineering fixed-base simulation facility of ONERA, Salon de Provence. Based on these test results, an innovative methodology is proposed and validated to determine the safe pilot workload limitation, from the measurements of the helicopter control displacements. In addition, it is proposed and validated innovative modifications on a classical pilot model enabling to follow complex predefined desired trajectories and provide the same level of control activity of a real pilot. A set of objective criteria, corresponding to the safety margins, is established in addition to the subjective criteria, corresponding to the safe pilot workload limitations. An offline simulation routine, so-called SholSim, is coded to run all models and verify the acceptability of the flight conditions, according to the subjective and objective criteria. Therefore, the present work presents the first estimation, in the literature, of the SHOLs fully obtained from offline tools, based only on pilot model predictions. The proposed methodology is promising, confirmed by predicting coherent limits when compared to the ones defined by the pilot-in-the-loop simulation trials.

This study aimed to develop and evaluate a method to obtain a proportional-integral-derivative (PID) controller. The controller is for a control surface that controls pitch motion, by using data from flight tests with an unmanned aerial vehicle (UAV). Finding a suitable method to develop the controllers is essential to make the UAV autonomous, whilst being stable and controllable. Before developing the PID, data from test flights were used to model a transfer function for the control surface with MATLAB's toolbox for system identification. Thereafter, using the transfer function, the PID was developed by using MATLAB’s toolbox for control systems. The whole method was evaluated by studying the rise time, settling time, and overshoot for the PID, and studying how well the transfer function fits with the flight data. The method of modeling the pitch motion with system identification and finding the PID gains has good potential to simplify the process of finding a PID controller. However, to acquire an accurate model for the pitch motion, which in turn can give a well-performing PID, an improved data sampling was suggested. Additionally, flight tests conducted before and after PID tuning, and in different conditions are recommended to be done in future studies. The flight test would work as a validation for the model to acquire a robust PID that performs as expected. / Syftet med denna studie var att utveckla och utvärdera en metod för att hitta en proportionerlig integrerande deriverande (PID) regulator. Regulatorn är för en kontrollyta som kontrollerar tipprörelsen genom att använda data från flygtester med en drönare. Att hitta en lämplig metod för att utveckla regulatorer är nödvändigt för att göra drönaren autonom, samtidigt som den är stabil och kontrollerbar. Innan PID:n utvecklades användes data från flygtester för att modellera överföringsfunktionen för kontrollytan med MATLAB:s programvara för systemidentifiering. Därefter, genom att använda överföringsfunktionen, utvecklades PID:n med MATLAB:s programvara för reglersystem. Hela metoden utvärderades genom att studera stigtid, insvängningstid och översläng för PID regulatorn, samt studera hur väl överföringsfunktionen modellerar flygdata. Metoden för att modellera tipprörelsen och att hitta PID förstärkningarna har en god potential att förenkla processen av att hitta en PID regulator. Däremot för att få en precis modell för tipprörelsen, vilket i sin tur kan ge en välpresterande PID, föreslogs det att förbättra datainsamlingen. Dessutom rekommenderades det i framtida studier att flygtester genomförs i olika förhållande, både före och efter att PID regulatorn har hittats. Flygtesterna skulle fungera som en bekräftelse för modellen för att få en robust PID som presterar som väntat. / Kandidatexjobb i elektroteknik 2022, KTH, Stockholm

The ability to gather and process information regarding the condition of forest fires is essential to cost-effective, safe, and efficient fire fighting. Advances in sensory and autopilot technology have made miniature unmanned aerial systems (UASs) an important tool in the acquisition of information. This thesis addresses some of the challenges faced when employing UASs for forest-fire perimeter surveillance; namely, perimeter tracking, cooperative perimeter surveillance, and path planning. Solutions to the first two issues are presented and a method for understanding path planning within the context of a forest-fire environment is demonstrated. Both simulation and hardware results are provided for each solution.

The interest of drones in all forms has exploded in the recent years. The development of multirotor vehicles such as quadcopters and octocopters, has reached a point where they are cheap and versatile enough to start becoming a part of everyday life. It is clear to say that the future applications seem limitless. This thesis goes through the steps of development, modelling and control design of an octocopter system. The developed octocopter builds on a concept of using the mini computer Raspberry Pi together with the code generation functionality of Matlab/Simulink. The mathematical modelling of the octocopter includes the thrust and torques generated by the propellers, added with gyroscopic torque. These are combined with the aerodynamic effects caused by incoming air. The importance of modelling the later mentioned effects has increased with the demand of precise controlled extreme manoeuvres. A full state feedback based hybrid controller scheme is designed against a linearized model, which makes use of the motor dynamics. The controllers show good performance in simulations and are approved for flight tests, which are conducted on two separate occasions. The octocopter makes two successful flights, proving that the concept can be applied on multirotor vehicles. However, there is a miss-match between the mathematical model and the physical octocopter, leaving questions for future work.