Under de senaste åren har produkterna blivit mer invecklade beträffande anslutningen, prestanda och funktionalitet. Därför är syftet av denna studie att undersöka hur komplexa system utvecklas och leds genom att genomföra fallstudie på olika svenska företag som utvecklar mekatroniska och cyber-fysiska system. Resultatet av denna studie har lett till identifieringen av många utmaningar som de undersökta företagen har och som i sin tur har lett till framställningen av ett analytiskt ramverk som diskuterar hur och vad man bör göra för att utveckla komplexa produkter på ett effektivt sätt, så att onödig komplexitet i produktutvecklingen kan reduceras. / In recent years, products have become more complex in terms of connectivity, performance and functionality. Therefore, this study aims at studying how complex products are developed and managed through conducting multiple case studies at different Swedish companies that develop mechatronic or cyberphysical systems. The results of this study is the identification of many challenges that the investigated companies have, which have led to a presentation of an analytical framework that discusses how complex product development projects can and should be managed in order to be efficient, in order to reduce unnecessary complexity in the way companies develop these complex products.

Unmanned Aerial Vehicles (UAVs) could play an important role in Search & Rescue (SAR) operations thanks to their ability to cover large, remote, or inaccessible search areas quickly without putting any personnel at risk. As UAVs are becoming autonomous, the problem of identifying humans in a variety of conditions can be solved with computer vision implemented with a thermal camera. In some cases, it would be necessary to operate with one or several small, agile UAVs to search for people in dense and narrow environments, where flying at a high altitude is not a viable option. This could for example be in a forest, cave, or a collapsed building. A small UAV has a limitation in carrying capacity, which is why this thesis aimed to propose a lightweight thermal solution for human detection that could be applied on a small SAR-UAV for operation in dense environments. The solution included a Raspberry Pi 4 and a FLIR Lepton 3.5 thermal camera in terms of hardware, which were mainly chosen thanks to their small footprint regarding size and weight, while also fitting within budget restrictions. In terms of object detection software, EfficentDet-Lite0 in TensorFlow Lite format was incorporated thanks to good balance between speed, accuracy, and resource usage. An own dataset of thermal images was collected and trained upon. The objective was to characterize disturbances and challenges this solution might face during a UAV SAR-operation in dense environments, as well as to measure how the performance of the proposed platform varied with increasing amount of environmental coverage of a human. This was solved by conducting a literature study, an experiment in a replicated dense environment and through observations of the system behavior combined with analysis of the measurements. Disturbances that affect a thermal camera in use for human detection were found to be a mixture of objective and subjective parameters, which formed a base of what type of phenomena to include in a diverse thermal dataset. The results from the experiment showed that stable and reliable detection performance can be expected up to 75% vegetational coverage of a human. When fully covered, the solution was not reliable when trained on the dataset used in this thesis. / Obemannade drönare (UAVs) kan spela en viktig roll i sök- och räddningsuppdrag (SAR) tack vare deras förmåga att snabbt täcka stora, avlägsna eller otillgängliga sökområden utan att utsätta personal för risker. För autonoma UAVs kan problemet med att identifiera människor i en mängd olika förhållanden lösas med datorseende implementerat tillsammans med en värmekamera. I vissa fall kan det vara nödvändigt att operera med en eller flera små, smidiga UAVs för att söka efter människor i täta och trånga miljöer, där flygning på hög höjd inte är ett genomförbart alternativ. Det kan till exempel vara i en skog, grotta eller i en kollapsad byggnad. En liten UAV har begränsad bärförmåga, vilket är varför denna avhandling syftade till att föreslå en lättviktslösning för mänsklig detektering med värmekamera som skulle kunna appliceras på en liten SAR-UAV för drift i täta miljöer. Lösningen inkluderade Raspberry Pi 4 och en FLIR Lepton 3.5 värmekamera gällande hårdvara, tack vare liten formfaktor och liten vikt, samtidigt som de passade inom budgetramen. Gällande detekterings-mjukvara användes EfficentDet-Lite0 i TensorFlow Lite-format tack vare en bra balans mellan hastighet, noggrannhet och resursanvändning. En egen uppsättning av värmebilder samlades in och tränades på. Målet var att identifiera vilka störningar och utmaningar som denna lösning kan påträffa under en sökoperation med UAVs i täta miljöer, samt att mäta hur prestandan för den föreslagna plattformen varierade när täckningsgraden av en människa ökar p.g.a. omgivningen. Detta löstes genom att genomföra en litteraturstudie, ett experiment i en replikerad tät miljö och genom observationer av systemets beteende kombinerat med analys av mätningarna. Störningar som påverkar en värmekamera som används för mänsklig detektion visade sig vara en blandning av objektiva och subjektiva parametrar, vilka utgjorde en bas för vilka typer av fenomen som skulle inkluderas i en mångsidig kollektion med värmebilder. Resultaten från experimentet visade att stabil och pålitlig detekteringsprestanda kan förväntas upp till 75% täckningsgrad av en människa p.g.a. vegetation. När människan var helt täckt var lösningen inte tillförlitlig när den var tränad på kollektionen som användes i denna avhandling.

Bird feeding is somthing most are familiar with, either when children are feeding the swans or adults using some type of bird feeder in the garden. This project took that as inspiration to create something that automatically feed the birds while also monitoring them by capturing a picture and sending out this information as a teet on Twitter. This thesis examined if it was possible to connect different components relatively simple in order to create something more advanced. Research of the components was the first step in order to ensure the ability to create such a product. The following components were used, a Raspberry Pi 3 b+, Raspberry Pi camera module, IKEA PIR sensor, zigbee USB dongel, ultrasonic sensor and a micro servo motor. These components were connected to the Raspberry Pi and tested individually to ensure quality and function. When successfully tested, implementing them together was done and later construction of the mounting brackets and housing was made. Testing was done and results were finalized. This showed that all of our research questions were successfully answered with positive results and further research around implementing AI and weather protection would be usefully to successfully make this a fully functioning product. / Fågelmatning är något de flesta de flesta känner till, antingen när barn matar svanar eller vuxna som har en fågelmatare i trädgården. Det här projektet tog det som inspiration för att skapa något som automatiskt matar fåglar samtidigt som den övervakar funktionen genom att ta kort och skicka denna information som en tweet på Twitter. Den här avhandlingen undersökte om det var möjligt att sammankoppla olika komponenter relativt enkelt för att skapa något mer avancerat. Forskning om komponenterna var det första steget i att undersöka om detta var möjligt. Följande komponenter kom att användas, an Raspberry Pi 3 b+, Raspberry Pi kameramodul, IKEA PIRsensor, zigbee USBdongel, ultraljudsensor och en micro servomotor. Dessa komponenter kopplades in i Raspberry Pi:en och testades individuellt för att säkerhetställa kvalite och funktion. När testerna var lyckade implementerades de tillsammans och konstruktionen av fästen och ytterhölje fördigställdes. Tester gjordes och resultat sammanställdes. Dessa visade att alla våra forskningsfrågor blev besvarade med ett positivt resultat och framtida forskning kring implementeringen av AI och väderskydd är något som skulle kunna möjliggöra detta att bli en fullt fuktionerande produkt.

Technology advances each day, with every advancement new and improved products are accompanied. Robots come in various shapes and sizes, from the size of a fly to the size of a human being. The purpose of this project is to further our understanding in how to build a robot, more specifically, a mono wheeled robot and design control systems enabling it to balance by itself. The robot is a one-wheeler with ducted fans on top. It is to balance with the help of the wheel in one direction and with ducted fans in the perpendicular direction.The robot succeeded in balancing with the wheel. However with help of the fans the robot only managed to balance for approximately 20 seconds. Analysing the frequency content from figures 5.2, 5.4, 5.3 resulted in finding frequencies under 1Hz being dominant in the output signals from the control system, observing this a clear oscillation frequency was only determined for the ducted fan system while the wheel system was non periodic. The study concluded that one cannot stabilize the control systems individually because that can lead to disturbances for the other. The results showed that even though the wheel’s control system was stable, it was affected by the second control system, causing disturbances. / För varje dag som går tar tekniken ett steg frammåt, hela tiden med nya och förbättrade produkter. Robotar kommer i olika former och storlekar, från storleken av en insekt till storleken av en människa. Syftet med detta projekt är att utvidga förståelsen över hur man bygger en robot, mer specifikt, en enhjulig robot samt hur man konstruerar ett reglersystem för att få roboten att balansera på egen hand. Roboten är en enhjuling med fläktar. Syftet är att bygga och programmera den till att balansera på egen hand, i ena riktningen med hjulet och i andra riktningen med fläktarna. Roboten lyckades balansera med hjälp av hjulet, men med fläktsystemet balancerade roboten endast i cirka 20 sekunder. Med hjäp av frekvenspspekrumen i figurer 5.2, 5.4, 5.3 försöktes en oscillationsfrekvens och periodtid tas fram, detta erhölls endast för fläktsystemet då hjulsystemet inte gav en tydlig oscillationsfrekvens. Slutsatsen som drogs var att det inte går att stabilisera de individuella systemen separat och sedan kombinera dem. Detta på grund av att det leder till att det ena systemet riskerar att agera som en störsignal till det andra systemet.

The objective of this project is to produce a prototype hydroponic farming solution with improved robustness from external fault factors. This means that the plants will not be grown in soil, but instead in water with a majority of its parameters being monitored and regulated. This with the aim of producing a more efficient and automatic system than traditional farming principles. Using less water and other harmful pesticides. The particular type of hydroponic system will be a NFT system (Nutrient Film Technique) which traditionally operates with a pump constantly feeding water to the plants. The main objective then is to find a way to reduce the reliance on this pump and make the system more robust. The result was a prototype hydroponic system that successfully could monitor and maintain predetermined growth parameters. It was also operate with a constant water flow without the need for constant pump usage. / Målet med detta projekt är att framställa en prototyp av ett hydroponiskt odlingssystem med förbättrad robusthet mot externa faktorer. Det innebär att växterna inte planteras i jord utan i vatten, där en majoritet av relevanta parametrar kan övervakas och kontrolleras. Detta med syftet att skapa ett mer effektivt och automatiserat system, jämfört mot traditionella jorbruksmetoder. Där mindre vatten används och helt utan bekämpningsmedel under växt processen. Det specifika hydroponiska odlingssystemet som kommer användas är ett NFT system (eng. Nutrient Film Technique) vilket traditionellt fungerar genom att konstant låta en pump bevattna växterna. Det primära målet är därför att minska beroendet på pumpen och göra systemet mer robust. Resultatet blev en prototyp av ett hydroponiskt system som kan mäta och styra faktorer som identifierats som viktiga för plantornas växtprocess. Systemet lyckades även med att hålla ett stabilt vattenflöde, utan användandet av en pump.

<p dir="ltr">Network models are essential for representing a myriad of real-world problems. Two of the most important categories of networks are centralized and distributed networks. In this thesis, we investigate the efficient resource allocation for one centralized communication network and two distributed epidemic networks.</p><p dir="ltr">In Chapter 2, we study three proposed centralized coded caching schemes with uncoded pre-fetching for scenarios where end users are grouped into classes with different file demand sets. We provide a lower bound for the transmission rate for the system with heterogeneous user profiles. Then the transmission rates of the three schemes are compared with the lower bound to evaluate their gap to optimality, and also compared with each other to show that each scheme can outperform the other two when certain conditions are met. Finally, we propose a cache distribution method that results in a minimal peak rate and a minimal average rate for one of the schemes when the users’ storage is relatively small compared with the size of the library.</p><p dir="ltr">In Chapter 3, we examine a discrete-time networked SIR (susceptible-infected-recovered) epidemic model, where the infection, graph, and recovery parameters may be time-varying. We propose a stochastic framework to estimate the system states from observed testing data and provide an analytic expression for the error of the estimation algorithm. We validate some of our assumptions for the stochastic framework with real COVID-19 testing data. We identify the system parameters with the system states from our estimation algorithm. Employing the estimated system states, we provide a novel distributed eradication strategy that guarantees at least exponential convergence to the set of healthy states. We illustrate the results via simulations over northern Indiana, USA.</p><p dir="ltr">In Chapter 4, we propose a novel discrete-time multi-virus SIR model that captures the spread of competing SIR epidemics over a population network. First, we provide a sufficient condition for the infection level of all the viruses over the networked model to converge to zero in exponential time. Second, we propose an observation model which captures the summation of all the viruses’ infection levels in each node, which represents the individuals who are infected by different viruses but share similar symptoms. We present a sufficient condition for the model to be strongly locally observable. We propose a distributed Luenberger observer for the system state estimation. We demonstrate how to calculate the observer gain for the estimator and prove that the estimation error of our proposed estimator converges to zero asymptotically with the observer gain found. We also propose a distributed feedback controller which guarantees that all viruses are eradicated at an exponential rate. We then show via simulations that the estimation error of the Luenberger observer converges to zero before the viruses die out.</p><p dir="ltr">We conclude in Chapter 5, where we summarize the findings of this thesis and introduce several challenging open research questions that arise from its results. These questions encompass a range of topics, including the design of optimal testing strategies for large populations, the investigation of estimation techniques in the presence of noisy measurement models, the extension of the SIR epidemic model to more complex models like SEIR and SAIR, and the exploration of efficient vaccine allocation schemes.</p>

Låssystem kan minska risken för inbrott och stöld, och vara ett verktyg för behöriga personer att få tillgång till lokaler och rum. Därför är det viktigt att moderna låssystem är pålitliga, öppnar snabbt och är säkra. Detta examensarbete undersöker om CAN (Controller Area Network) är ett idealt kommunikationsprotokoll för ett säkerhetssystem av dörrlås, med syftet att utföra en fallstudie av CAN-protokollet. Detta sker genom att analysera ett låssystem från ASSA vars kommunikationsprotokoll mellan styroch låsenhet misstänktes använda CAN-protokollet mellan dess styrenhet och låsenhet. Slutsatsen av analysen var att låssystemet från ASSA inte kommunicerade via CAN. För att bevisa dettaåterskapades signaler med elektriska standardinterface RS-485. Det sista steget vara att utveckla ett eget låssystem med CAN som kommunikationsprotokoll, och sedan skulle de två låssystem jämföras. För att testa detta programmeras två kretskort av typen ESP32-PoE till en styrenhet och en låsenhet. Ett låssystem designades på ett kopplingsdäck innan den ersattes av två PCBs. Slutresultatet var ett motorlås och en styrenhet som konstruerades och validerades i ett kopplingsdäck. Av de två kretskorten som utvecklades fungerade kontrollenheten som förväntat, medan låsenheten hade problem med dess motor. Den kunde dock klara av dess andra uppgifter som att läsa signaler från styrenheten via en 10 meter kabel och läsa signaler från dess dörrläge givande magnetsensor. Det demonterade låssystemet sänder signaler snabbare, och öppnar låset ungefär lika snabbt, men är inte lika säker som den kommersiella låssystemet för att CAN har restriktiva säkerhetsåtgärder. / Lock systems can reduce the risk of burglary and theft, and be a tool for authorized persons to access premises and rooms. Therefore, it is important that modern lock systems are secure, reliable and open quickly. This thesis investigates whether CAN (Controller Area Network) is an ideal communication protocol for a door lock security system. This is done by analyzing a mechanical lock system from ASSA which was suspected of using CANbus as a communication protocol between the control unit and lock unit. Then the lock and control units were analyzed. The conclusion of the analysis is that the lock system did not communicate via CAN. To prove this, signals were re-created with the electrical standard interface RS-485.The final step was to construct a lock system with CAN as a communication protocol, and then the two lock systems would be compared.To test this, two ESP32-PoE development boards are programmed into a controller and a locking device. A mechanical door lock system was designed on a breadboard before being replaced by two PCBs. Of the two circuit types that were developed, the control unit worked as expected, while the motorlock unit had problems with it’s motor. However, it was able to handle its other tasks such as reading signals from the controller via a 10 meter cable and reading signals from its door locating magnetic sensor. The disassembled lock system sends signals faster, and opens the lock approximately as quickly, but is not as secure as the commercial CAN lock system has restrictive security measures.

<p>Traditional robots and soft robots have often been treated as two distinct options for design, a dichotomy between stiffness and compliance. In reality, they compose two ends of a spectrum, and there has been research to soften traditional robots and stiffen soft robots. The latter option has seen a large variety of techniques to actively and selectively create stiffness in an otherwise soft robot. The common disadvantage concerning all of them is the need for constant energy input. In this work, a first-of-its-kind method for a permanent stiffness of a growing robot is explored and tested.</p> <p>First, I show the qualitative and quantitative testing of the stiffening method, expanding insulation foam, both by itself and when applied to a vine robot. With this knowledge, I investigate a design to apply the foam to a growing robot as it moves, taking advantage of the properties of the foam to coat a vine robot as needed. This selective foam placement unlocks various unique capabilities like adhering to its environment, imparting & resisting large forces, and isolating sections of its body. Finally, these traits are highlighted in three demonstrations, proving the efficacy of this unique method as well as affirming the utility of permanently stiffening a soft robot. In the future, the work in this thesis can help open the way for permanent deployable robotic structures and soft robots in roles more traditionally used for rigid robots.</p>

<p>Multirotor unmanned aerial vehicles (UAVs) added with the ability to physically interact with the environment has opened endless possibilities for aerial mobile manipulation tasks. With the unlimited reachable workspace and physical interaction capabilities, such robots can enhance human ability to perform dangerous and hard-to-reach tasks. However, realizing aerial mobile manipulation in real-world scenarios is challenging with respect to the diversity in aerial platforms, control fidelity and susceptibility to variations in the environment. Therefore, the first part of the dissertation provides tools to  classify and evaluate different multirotor designs. A measure of responsiveness of a multirotor platform in exerting generalized forces and rejecting disturbances is discussed through the control bandwidth analysis. Superiority in control bandwidth for fully-actuated multirotors is established in a comparison with equivalent under-actuated multirotors. To further classify and distinguish multirotor platforms, a new mobility measure is proposed and compared by surveying all aerial platforms employed for aerial mobile manipulation. In compliance to the control bandwidth analysis, the mobility measure for fully-actuated multirotors is relatively higher making them better suited for manipulation tasks. </p> <p><br></p> <p><br></p> <p>Aerial physical interaction, as a part of aerial mobile manipulation, with partially unknown environments is challenging due to the uncertainties imposed while dexterously exerting force signatures. A hybrid physical interaction (HyPhI) controller is proposed to enable constrained force contact with a steady transition from unconstrained motion, by squelching excess energy during initial impact. However, uncertainties posed by the partially unknown environment requires to understand the surrounding environment and their current physical states, that can enhance interaction performance. The limited resources and flight time of the multirotors requires to simultaneously understand the environment and perform aerial physical interactions. Inspection-on-the-fly is an uncanny ability of humans to intuitively infer states during manipulation while reducing the necessity to conduct inspection and manipulation separately. In this dissertation, the inspection-on-the-fly method based HyPhI controller is proposed to engage in a steady contact with partially unknown environments, while simultaneously estimating the physical states of the surfaces. The proposed method is evaluated in a mockup of real-world facility, to understand the surface properties while engaging in steady interactions. Further, such inspection of surfaces and estimation of various states enables a deeper understanding of the environment while enhancing the ability to physically interact. </p>

<p>Soft robotics is concerned with the modeling and designing of devices fabricated from materials with low Young’s moduli—much less than that of metal— that mimic the input/output operation and physical task utility of robotics.  The inherent compliance of soft robots lends these devices an adaptability and a capacity for human-machine interaction beyond that of conventional robotics. Multistable soft robotic grippers are a subset of the technology at the intersection of soft robotics and multistable structures. Multistable structures are continuum systems that exhibit more than one statically stable state, each associated with a strain energy minimum. The existence of these energetic minima allows the structures to adopt different stable configurations that can provide a reference point for open loop control schemes. Multistable soft robotics takes advantage of both the adaptability of soft robotics and the potential for simplified control of multistable structures.</p> <p>Achieving simplified control for soft robotics is a necessary milestone in creating functional and applied soft robots. </p> <p>This work presents a means for simple open-loop control of a multistable soft robotic gripper that is adaptable, controllable, and robust. The behavior is illustrated through a gripper geometry described by specific design parameters resulting in a near infinite design space. An analytical model based on lumped parameter springs is derived, allowing us to search the design space in a tractable fashion. Specifically, we predict the system’s stable states for any given design instance by searching for local minima in the energy landscape formed by a spring lattice representation of our device. The lattice is composed of linear, bistable, and torsional springs—each of which contributes to the energy landscape of the system. We validate our model against Finite Element simulations of our device, showing good agreement with the proposed model. The aptitude of the model sheds light on the fundamental mechanics of our soft robotic gripper topology, laying the foundation for efficient design optimization and simplified control of soft robots.</p>