To advance crop monitoring techniques in horticultural tree crops, earlier research has examined the relationship between crop vigor (height, canopy den- sity, health) as assessed by remote sensing technologies and aspects such as fruit quality and yield requirements. In recent years, structure-from-motion image pro- cessing techniques have been widely used to generate orthomosaics and 3D point clouds from RGB and multispectral (MS) imagery acquired by unmanned aerial vehicles. However, this process requires a lot of computing power and can be expensive, especially for large commercial orchards. However, studies have been scarce comparing the accuracy of different remote sensing technologies in deter- mining tree height and plant area index. Light detection and ranging (LiDAR) is an alternative method to generate 3D point clouds that requires less compu- tational power. This study assessed the accuracy, processing parameters, and limitations of UAV-based RGB, MS, and LiDAR data for measuring cherry trees’ height and plant area index in a high-density orchard in Malauc`ene, southeastern France. Furthermore, the plant area index changes of 5 different cherry culti- vars were assessed during the growth cycle. Overall, the LIDAR data provided the highest accuracy for tree height measurements around harvest (R² = 0.923, RMSE = 0.215 m) and the beginning of leaf senescence (R² = 0.863, RMSE = 0.218 m). LiDAR-derived plant area index also produced the best accuracy at May (R² = 0.48 and RMSE = 0.42) and October (R² = 0.45 and RMSE = 0.59). Our findings demonstrate that UAV-based LiDAR data provide an effective and rapid means for measuring cherry tree height and plant area index over time. Such information can serve as a general indicator of tree health and aid growers in making informed agricultural crop monitoring and management decisions.

Obemannade system blir allt vanligare både på den militära och kommersiella marknaden. Unmanned Aerial Vehicle, i vardagsspråk benämnt som drönare, är ett flygplan som ombord saknar en mänsklig pilot. Då utbudet och efterfrågan av obemannade farkoster ökar måste tillverkarna lägga mer fokus på att kunna erbjuda hela system, vilket innebär att vid försäljning kan ett komplett system för obemannade farkoster erbjudas. Därför är behovet av tillbehör och kringutrustning idag lika viktigt som det obemannade flygplanet. Unmanned Systems Group grundades 2012 med verksamhet i både Schweiz och Sverige. Företaget förser den globala marknaden med innovativa produkter och tekniska lösningar inom området för Remotely Piloted Aircraft Systems. Veksamhetskontoret i Linköping utvecklar helhetslösningar av obemannade flygplan, vilket innebär att flygplanet har möjlighet att operera autonomt. Det betyder att flygplanet kan operera oberoende av i vilken miljö den befinner sig i. En förutsättning för autonoma flygplan är att start ska kunna ske när tillfredställande startbana saknas, vilket ofta möjligörs av en startmekanism. Unmanned Systems Group önskar få hjälp med utveckling och konstruktion av en startkatapult som är ämnad för deras flygplattform Discoverer. Utvecklingsarbetet skulle genomföras från grundidéer av startmekanismer till ett koncept som vidareutvecklas och konstrueras i en CAD-modell tillsammans med ett Excel-baserat beräkningsverktyg. I mån av tid skulle modellen resultera i en prototyp som kan utvärdera och verifiera dess teoretiska dokumentation. Följande examensarbete utvecklar och konstruerar en startkatapult för flygplattformen Discoverer för att ge den bättre autonoma egenskaper. Slutresultatet ska vara en CAD-baserad modell tillsammans med ett Excel-baserat beräkningsverktyg som levereras till Unmanned Systems Group vid avslutat och godkänt examensarbete. Modellen och beräkningsverktyget ska tillsammans ge det slutgiltiga konceptets teoretiska funktion och prestanda. Examensarbetets slutresultat är en CAD-modell som konstruerats med syftet att tillverka en prototyp för att verifiera det framtagna beräkningsverktyget. Det slutgiltiga konceptet använder ett pneumatiskt energisystem som med hjälp av komprimerad luft, en cylinder med en projektil och en släde accelererar flygplattformen till sin givna utgångshastighet. Startkatapultens struktur och komponenter har konstruerats för att tillsammans utgöra en stabil och säker prototyp. / Unmanned systems are becoming increasingly common in both the military and commercial market. Unmanned aerial vehicle, or in everyday language referred to as drones, is an aircraft that do not have a human pilot onboard. As the supply and demand of unmanned aircraft increases, manufacturers must put more focus on a complete system, meaning that the manufacturer can offer a complete system for unmanned aircraft. Therefore the need of accessories and peripherals are today as important as the unmanned aircraft. Unmanned Systems Group was founded in 2012 with operations in both Switzerland and Sweden. The company serves the global market with innovative products and technical solutions in the field of remotely piloted aircraft systems. The office in Linköping develops complete solutions of unmanned aircraft, which means that the aircraft is able to operate autonomously. This means that the aircraft can operate independently on the environment. A prerequisite for autonomous aircraft is to be able to start when a satisfying runway is missing, which often requires a starting mechanism. The Unmanned Systems Group wishes to get help with the development and construction of a start catapult, which is intended for their aircraft platform Discoverer. The development would be carried out from basic ideas of a starting mechanism to a concept developed and designed as a CAD model, along with an Excel-based calculation tool. If there is time, the model would result in a prototype that can evaluate and verify the catapult theoretical documentation. The following master thesis develops and designs a start catapult flight platform Discoverer to give it more autonomic properties. The end result is a CAD-based model together with an Excel-based calculation tool that is delivered to the Unmanned Systems Group when the master thesis is finished and approved. The model and calculation tool will together give the final concept its theoretical function and performance. The end result is a CAD-model designed with the purpose to produce a prototype to validate the designed calculation tool. The final concept uses a pneumatic energy system by using compressed air, a cylinder with a projectile and a sled to accelerate the aircraftplatform to its given releasespeed. The structure of the start catapult and its components are designed together to provide a stable and secure prototype.

This thesis documents the design and development of a robust backpackable proof-of-concept unmanned aerial vehicle. The unmanned aerial vehicle?s design departs from existing configurations in utilizing a keel beam fuselage which replaces the enclosed fuselage by a flat keel beam on which the sensors, the autopilot, their related power sources, and flight control systems are mounted. The keel beam fuselage is provides enhanced mounting capability for multiple sensors and quick reconfiguration in the field. The keel beam fuselage can also be manufactured quicker than a traditional enclosed fuselage. The objective of this study is to demonstrate that the keel beam configuration is a viable design for an unmanned aerial vehicle and the challenges of modular, plug-n-play hardware. The design, fabrication, and flight testing of the air vehicle are addressed.

Deploying unmanned aerial vehicle (UAV) networks to provide coverage for outdoor users has attracted great attention during the last decade. Terrain information requires extensive attention in outdoor UAV networks, and it is one of the most important factors affecting coverage performance. Providing tractable models and common methods is necessary to generalize the terrain-based outdoor UAV positioning strategies. In this thesis, we demonstrate that UAVs can provide stable coverage for regularly moving users based on the existing local terrain reconstruction methods with UAV sampling. Next, a coarse-grained UAV deployment can be performed with a simple set of parameters that characterize the terrain features. A stochastic geometry framework can provide general analytical results for the above coarse-grained UAV networks. In addition, the UAV can avoid building blockage without prior terrain information through real-time linear-trajectory search. We proposed four algorithms related to the combinations of collecting prior terrain information and using real-time search, and then their performances are evaluated and compared in different scenarios. By adjusting the height of the UAV based on terrain information collected before networking, the performance is significantly enhanced compared to the one when no terrain information is available. The algorithm based on real-time search further improves the coverage performance by avoiding the shadow of buildings. During the execution of the real-time search algorithm, the search distance is reduced using the collected terrain information.

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Surveillance of countries' borders is of greatest interest to monitor to detect enemies. Saab's radar aircraft has air, ground and sea surveillance capabilities and is characterized by the large radar that attaches to the fuselage of the aircraft. When designing future aircraft and unmanned vehicles, weight and energy efficiency are sensitive parameters to consider. The weight of aircraft and its equipment has an important impact on, among other things, fuel consumption and thus how long they can stay in the air. In addition, all mission equipment must be provided with cooling to avoid overheating. The aim of this study has been to analyze and evaluate existing refrigeration systems in some of Saab's radar aircraft during various operational scenarios and also review alternative designs for future vehicles and carbon dioxide as future cooling media. The refrigeration systems Environmental Control System and Mission Air Cooling System ensure that cabin and cockpit areas are tempered and pressurized and that all heat generated in the equipment is transported away and out to the surrounding atmosphere as a heat sink. The Environmental Control System uses ambient air as media. Compressed air is drained from engines or an auxiliary power unit and supplies the refrigeration system with air. The Mission Air Cooling System is a conventional refrigeration machine with R134a as the refrigerant. The existing cooling circuit absorbs heat in the evaporator which is placed in the air distribution where the air circulates and cools the equipment. The refrigerant then transports the heat to the surrounding atmosphere. Carbon dioxide as a refrigerant has been used since the 19th century. With the ongoing phasing out of conventional refrigerants, R134a included, carbon dioxide is starting to become relevant again. Despite carbon dioxide's good heat transfer properties, there is a major challenge regarding the high-pressure conditions, which places demands on the components of the refrigeration system. Carbon dioxide can reduce pressure losses and dimensions of components and pipelines as well as reduce installation weight. The performance of the refrigeration systems has been evaluated based on their coefficient of performance and how much energy from the engine corresponds to the amount of fuel that the refrigeration systems require. Pressure, temperature and enthalpy conditions were developed in a simulation program, alternatively previous calculation templates were reused to calculate heat transfers and work in each refrigeration system. In addition, the installation weights of the refrigeration systems in relation to each other were provided in order to be able to analyze these against other parameters, such as performance and complexity, for future aircraft and unmanned vehicles. An alternative construction in the Mission Air Cooling System was investigated where the air distribution is excluded and instead the cooling circuit is led all the way to the devices. The evaporator thus functions as a cooling plate. The calculations for a carbon dioxide machine were carried out using research articles. For the Environmental Control System, it turned out that the design of the air intake together with the air velocity profile in some cases generates low mass flows, which causes abnormal heat exchanges and temperature conditions in the cabin and cockpit. The Mission Air Cooling System had better performance in terms of coefficient of performance but has a long chain of energy conversions required for the electricity supply which contributes to energy losses. Calculations carried out for a carbon dioxide machine resulted in the compressor's displacement being able to be reduced by 89\%. Finally, based on the analyses and calculations carried out, a section is presented that explains which parameters should be considered for future designs for unmanned vehicles, as well as a figure that can be seen as an example of a system structure. The system structure is a conventional refrigeration machine with carbon dioxide as the refrigerant. Based on the analyses made regarding the installation weight and the performance of the refrigeration systems, it is likely that the presented system structure also contributes to the lowest weight and is an example of a refrigeration system in future aircraft and vehicles.

This thesis introduces a novel framework for enabling intelligent machines and robots with the fifth-generation (5G) cellular network technology. Autonomous robots, such as Unmanned Aerial Vehicles (UAVs), Autonomous Guided Vehicles (AGVs), and more, can notably benefit from multi-agent collaboration, human supervision, or operation guidance, as well as from external computational units such as cloud edge servers, in all of which a framework to utilize reliable communication infrastructure is needed. Autonomous robots are often employed to alleviate humans by operating demanding missions such as inspection and data collection in harsh environments or time-critical operations in industrial environments - to name a few. For delivering data to other robots to maximize the effectiveness of the considered mission, for executing complex algorithms by offloading them into the edge cloud, or for including a human operator/supervisor into the loop, the 5G network and its advanced Quality of Service (QoS) features can be employed to facilitate the establishment of such a framework. This work focuses on establishing a baseline for integrating various time-critical robotics platforms and applications with a 5G network. These applications include offloading computationally intensive Model Predictive Control (MPC) algorithms for trajectory tracking of UAVs into the edge cloud, adapting data sharing in multi-robot systems based on network conditions, and enhancing network-aware surrounding autonomy components. We have identified a set of key performance indicators (KPIs) crucially affecting the performance of network-dependent robots and applications. We have proposed novel solutions and mechanisms to meet these requirements, which aim to combine traditional robotics techniques to enhance mission reliability with the exploitation of 5G features such as the QoS framework. Ultimately, our goal was to develop solutions that adhere to the essential paradigm of co-designing robotics with networks. We thoroughly evaluated all presented research using real-life platforms and 5G networks.

Ducted fan VTOL UAVs are currently being designed for use by the Army for surveillance and reconnaissance in the battlefield. The vehicle tested in this research is part of the Honeywell MAV program. Able to be carried in a backpack by a single soldier, it has a duct diameter of 11.5-in. and weighs approximately 20-lbs at takeoff. It is designed for flight up to 50-knots with fan speeds varying between 5000 and 8500 RPM. Reynolds numbers, based on the duct diameter, were on the order of Re = 0.96 x 106 to 4.6 x 106. Various control effectors were mounted to the vehicle and tested for maximum control authority to reduce the nose-up pitch moment created during forward flight or with crosswinds present. Static and wind tunnel tests were conducted to measure each control effector's performance. Box vanes, mounted downstream of the duct, utilized four assemblies, each with three vanes and one flap. This configuration showed adequate results in generating a nose-down pitch moment. Duct deflectors, mounted on the windward strut upstream of the duct, reduced the windward lift produced by both the fan and duct, resulting in a nose-down pitch moment. Opposed vanes, utilizing two vanes and flaps for each of the four assemblies, were designed with the same surface area as the box vanes. With each pair capable of independent vane movement, the opposed vanes were tested with the vanes rotating in tandem for a basic elevator deflection and with the leading edges touching, disrupting the flow at the duct exit. Opposed vanes combined the capabilities of the box vanes and duct deflector. Results show that the opposed vanes were the most practical control effector, offering the most control authority for maximum nose-down pitch moment (up to 80% better) with minimal loss in thrust. / Master of Science

As unmanned aerial vehicles (UAVs) increasingly become integral to surveillance and reconnaissance (S&R) operations, their susceptibility to cyber threats poses significant risks to operational integrity. The current cybersecurity protocols often fail to address UAV operations’ unique vulnerabilities and challenges in S&R contexts, highlighting a gap in specialized cybersecurity strategies. This research adapts the MITRE ATTACK framework to enhance cybersecurity approaches, safeguarding UAVs against evolving cyber threats. This thesis maps existing vulnerabilities against comprehensive tactics, techniques, and procedures (TTPs) through a scenario-based analysis. Hypothetical and practical S&R operation case studies demonstrate the applicability of proposed cybersecurity strategies, validating their effectiveness in mitigating specific threats and the need for more specified cybersecurity protocols. The findings advocate for continuous innovation and vigilance in UAV cybersecurity, contributing to the protection of UAVs in S&R missions and emphasizing the dynamic nature of cybersecurity challenges in UAV operations.