Traditional quadcopter flight controllers use microcontrollers to run the code that keeps the drone in the air, and when more processing power or versatility is needed the same microcontrollers are used in tandem with Linux-based single-board computers. It would be cheaper and reduce complexity if the single-board computer could entirely replace the microcontrollers. We investigate whether it is possible to run a quadcopter using a Linux single-board computer as the flight controller, with no microcontrollers and otherwise the same hardware as used in hobby-grade quadcopters. We attempt to find out what the potential issues are and how to get around or mitigate them. To test it, a quadcopter will be built from hobby parts and the flight control software to be run on the flight controller will be developed. More specifically, the pulse-width modulation signals to the motor speed controllers are checked for stability and various methods of acquiring the radio control input in the form of pulse-width modulation signals are evaluated. The speed at which the flight control software is running is measured under different circumstances—with and without load and with and without mitigative measures active. We conclude that it was not possible to run a quadcopter using only the chosen Linux SBC as flight controller. The reason was because we could not accurately measure the radio control input, although there may be other additional issues. We did find that CPU time did not seem to be an issue even when an artificial stress was placed on the system, despite not being a real time system, and even less of an issue when the mitigation techniques discussed were applied.

The Thesis objective is the design and implementation of the universal control system for a flying robot, quadrotor concept. The first part deals with ways of solving program for microcontrollers. The special attention is given to the FreeRTOS real-time operating system, which is designed for microcontrollers. The second part of the Thesis is focused on the description of the chosen microcontroller LM3S8962 and the hardware solution. One chapter is devoted to the integration of the robot to the Cassandra-WPF robotic control system. The third part deals with the identification of the new robot construction and the mathematical model creation. Using the model controllers for stabilization pitch and roll are designed and their functionality is verified on a physical model. The last part of the Thesis is focused on the FreeRTOS implementation and the control application creation.

This student paper discusses basic concept of quadrocopter for purpose of academic platform for testing and development. Paper includes basic overview of construction, stabilization and controlling of quadrocopter. As result of this paper is presented concept of quadrocopter and its constructed prototype with included software console for wireless control under Android system.

In Abisko National Park there are a numberof weather stations. To be able toretrieve the data from the nodes in thefuture a Quadrocopter-prototype has beendeveloped during this master thesisproject as a first step. A quadrocopter isa helicopter with four rotors placed in across formation. The quadrocopter cannavigate autonomous between different GPSpositionsthat are updated during flighttrough Xbee-modules. All levels fromsources code, design of the electronics todevelopment of the chassis was performedduring the project. During GPS-navigationthe quadrocopter can achieve a stationaryposition with a mean stationary offset ofless than 0.5 meters even in light winds. / I Abisko Nationalpark finns det ett antal väderstationer. För att på sikt kunna läsa av väderdata från dessa har en quadrocopter-prototyp utvecklats i detta examensarbete. En quadrocopter är en helikopter med fyra rotorer placerade i ett kryss. Quadrocoptern kan navigera autonomt mellan olika GPS-positioner som ges trådlöst via Xbee-moduler. Alla nivåer från källkod, design av elektronik till utformning och tillverkning av chassit har gjorts inom detta projekt. Vid GPS-navigering kan quadrocoptern uppnå en stationär position med en medelvärdesavvikelse mindre än 0.5 meter trots lättare vindar.

This thesis describes the design and implementation of systems for automatic landing and stabilization of air vehicle known as Quadrocopter. It focuses on image processing from a camera placed on board of the robot. The aim of image processing is detect landing target and calculate the distance from the desired position. Further is solved vertical stabilization for higher altitudes. For this function is measured atmospheric pressure. Conversely, for low altitude flight is used a ultrasonic range finder. In the conclusion is solved the implementation of the system.

UAV applications have witnessed a great leap during the last decade including aerial photography, surveillance, inspection, mapping and many other applications. Using UAVs has many advantages over manned aerial vehicles. Reducing costs and avoiding putting human lives in danger are two major benefits. Currently, most of the UAVs are remotely controlled by human operators, either by having Line of Sight between the operator and the UAV or by controlling it from a ground control station. This may be fine in short missions. However, manually executing long and boring missions adds much inconvenience on the human operators and consumes more human resources. In addition, there is always the risk of losing the connection between the UAV and the human operators which leads to unpredicted, and probably catastrophic, consequences. The objective of this work is to reduce this inconvenience by moving the decision making responsibility from the human operators to the mission control system mounted on the UAV. In other words, the target is to design an on-board autonomous mission control system that has the capability of making decisions on-board and in real-time. Expert system technology, which is a type of artificial intelligence, is used to reach the autonomy of the target UAV. Expert system has the advantage of dealing with uncertainty during the mission execution. It also makes the system easily adaptable to execute any mission that can be described in form of rules. In this thesis, the design, implementation and testing of the expert system-based autonomous mission controller (ESBAMC) is covered. The target mission used to prove the feasibility of the proposed approach is the inspection of power poles. Power pole insulator is autonomously inspected by capturing three pictures from three different points of view. The proposed system has been successfully tested in simulation. Results show the performance and efficiency of the system to make decisions in real-time in any possible situation that may occur during the execution of the considered mission. In the near future, it is planned to test the proposed system in reality.

Die Auswahl an Hardware und Software auf dem Drohnen-Markt nimmt stetig zu. Autopilot-Software wie z. B. ArduCopter bietet bereits die Möglichkeit eine vor dem Flug definierte Liste von Wegpunkten automatisiert abzufliegen. Im Rahmen dieser Arbeit wird eine Software entwickelt, die dynamische Flugroutenplanung ermöglicht. Befindet sich beispielsweise ein Hindernis auf der aktuellen Flugbahn, berechnet ein Pfadplanungsalgorithmus eine neue Route ohne Kollision um dieses Hindernis herum.

Testning av flygkontroller på en verklig kvadrokopter är en farlig och utmanande process eftersom kvadrokoptern kan krascha om flygkontrollern inte fungerar eller ifall operatören saknar flygerfarenheter. Den nuvarande lösningen är att montera kvadrokoptern i en mekanisk anordning som möjliggör testning av flygkontroller i säkra miljöer. Problemet med de befintliga testanordningarna är att de inte kan ge realistiska simuleringsförhållanden eftersom de i viss mån påverkar kvadrokopterns rörelse med följden att flygkontroller som utvecklas har begränsad grad av kontroll på kvadrokoptern. Syftet är att utforma en mekanisk anordning som ska ge möjlighet att både testa samt övningsflyga kvadrokoptern utan risk för personliga och materiella skador. Målet är att ta fram ritningar som ska kunna utgöra underlag för framtagning av en testprototyp. En litteraturstudie på befintliga testanordningar genomfördes som användes som underlag tillsammans med kvalitetshuset för att ta fram en kravspecifikation. Därefter genererades ett antal koncept som utvärderades med hjälp av beslutsmatris. Det valda konceptet modellerades sedan i CAD-programmet och utifrån den virtuella modellen konstruerades en verklig modell i trä som testades för att verifiera dess funktion. Resultatet är en fjäderbalanserad testanordning med sex frihetsgrader. Det är en konstruktion i aluminium innehållande en mekanisk arm som ger tre translationsfrihetsgrader, ett kulledsfäste som ger tre rotationsfrihetsgrader samt dragfjädrar för att tyngdkraftskompensera systemet. Testning av trä-modellen uppvisar att kvadrakoptern måste framföras i full fart för att styras tillsammans med armen eftersom friktionen mellan testanordningens leder är hög. Under förutsättning att friktionen mellan lederna kan hanteras verkar det att testanordningen uppfyller de ställda teoretiska förutsättningarna för att inte ha någon väsentlig påverkan på kvadrokoptern. Ändå kravs det kvalificerade tester innan något påstående att testanordningen inte påverkar kvadrokopterns rörelse och därmed kan ge realistiska flygsimuleringsförhållanden, ska kunna anges. / Testing of autonomous flight controllers on a real quadrocopter is a dangerous and challenging process because the quadrocopter can crash in case the flight controller does not function properly or in case the operator has no flight experience. The current solution is to mount the quadrocopter on a teststand, which allow the testing of flight controller in safe environments. The problem with the existing teststands is that they cannot provide realistic free flight conditions as they, to some extent, affect quadrocopter’s movement. Consequently, the developed flight controller is partially able to control the quadrocopter. The purpose with this study is to design a mechanical device for use in testing and learning to fly a quadrocopter without the risk of crashing the flying model or harming the people involved. The goal is to provide drawings for developing a test prototype.In order to understand the problem a literature review of previous test devices was carried out. The findings from the literature review were used in combination with Quality Function Deployment technique to create a House of Quality and thus develop a set of engineering specifications. After that, a number of concepts was generated and then evaluated by Pugh’s method. The selected concept was modeled in the CAD-software and based on the virtual model, a real model made of wood was constructed and tested in order to verify the function of the testbed. The final result is a spring-balanced test device with six degrees of freedom. It is a structure consisting of a mechanical arm providing three translational degrees of freedom, a swivel joint with three rotational degrees of freedom and a set of extension springs to achieve gravity balancing. The experimental results from the wooden model shows that the quadrocopter is required to fly at full speed in order for it to operate with the arm due to the high friction between the joints. Under the condition that the friction between the joints can be managed, the test device seems to fulfill the theoretical requirements for simulating free flight condition. Nevertheless, it requires specialized and advanced testing before any assertion that the test device does not affect the dynamics of quadrocopter and thus it can provide completely realistic flight conditions, can be made.

In this paper, an introduction of the challenge of High Voltage Power Line Detection and some methods about solving the similar problem are talked about. To get a better result, a sort of new methods is developed for detecting and tracking high voltage power lines in the field of high voltage power line inspection by using Unmanned Aerial Vehicle (UAV). With the fast development of automated technology, a solution of real-time detecting and tracking of high voltage power lines can be considered on UAV instead of human work. The usability of Intersection Point Algorithm is the main task for detect the power lines from the preprocessing image. There are many lines located in the preprocessing image in different directions, which get crossing with each other many times. To eliminate the false lines, some invariant features for Intersection Point Algorithm are needed. The intersection points inside of a small region and quite similar directions can probably be considered as the intersection point of power lines. Therefore, three methods are considered for grouping points, which conform to the features of intersection points of power lines. There should be only one concentrated area, which represents both power lines and heading direction of it. Method one is to select the points based on distance of points. Method two is to select the overlap region of the circles based on overlap layers. And method three is searching the overlapped layers by using Sliding Window. Result evaluation in Project APOLI is done with the Hit, Miss, Fail standard.

In flying robots, stability control is often very sensitive to the actuator performances, and the software module performing the controller, is usually subjected to a long and difficult tuning phase strongly dependent on the specific actuator used. The actuators are often electric motors equipped with propellers. The motor and propeller combination performs differently for every choice of components adopted, even if they are provided by the same vendor with the same part family. The project aims to develop an intelligent actuator module for flying robots composed by a BLDC motor and a propeller, which is invariant to the specific motor and propeller adopted. By gathering the force data of the four used on a quadrocopter, the force and control signal relation could be defined and stored into the program memory of the control board. A battery monitor and a Force-PWM controller was implemented such that it takes force as input and outputs the desired PWM-signal. Tests were made on a prototype of Iqarus quadrocopter and by mounting it with ropes to the floor, it was tested on the lift-off phase. The experiment showed theoretical and practical results, which concludes that the quadrocopter maintained the ability to lift right upwards without any remaining control, assuming proper weight balance of the quadrocopter. / Inom flygande robotar, är stabilitet kontrollen oerhört känsligt till styrdonets prestation, och mjukvaru modulen som utför kontrollen, är ofta förknippad med en lång och problematisk justerings fas starkt beroende av de enskilda styrdonen. Styrdonen är ofta elektriska motorer med propeller. Motor och propeller kombinationen uppträder olika för varje val av komponent, även om komponenterna är försedda från samma återförsäljare och modell. Syftet med detta projekt är att utveckla en intelligent styrdons modul för flygande robotar, omfattad av en BLDC motor och propeller, som blir oberoende av den särskilda motor och propeller kombination som används. Genom att samla kraft data för de fyra styrdonen som används på en quadrocopter, kunde relationen mellan kraft och kontroll signal bli definierad och lagrad i program minnet för kontrol kortet. En batteri monitor och en Kraft-PWM kontroller implementerades, vilket tar kraft data som ingång och skickar ut motsvarande PWM-signal som utgång. Tester var gjorda med en prototyp av Iqarus quadrocopter och genom att binda fast den med rep till golvet, testades den för upplyfts fasen. Experimenten visade teoretiska och praktiska resultat, vilket visar att quadrocoptern bevarade förmågan att lyfta rakt uppåt utan någon övrig kontroll, förutsatt ordentlig vikt balans av quadrocoptern. / <p>Hejsan,</p><p>Detta ar den nya versionen, som ska ersatta den gamla versionen som blev uppladdad 6/11-13.</p><p>Tack,</p><p></p><p>Mvh</p><p>Amil Lafih</p>