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Norsk sammendrag Denne oppgaven er addresert til forskere og produktutviklere. Den har som hensikt å gi innsikt i løsing av komplekse sensorproblemer i the fuzzy front end av produktutvikling. Sensorer bygger bro mellom fysiske fenomener og prosessering i cyberfysiske systemer og involverer tverrfaglig praksis ved implementering. Som sådan er innovasjonsprosjekter som utforsker bruken av sensorer i the fuzzy front end ofte komplekse. Forskere og produktutviklere må beslutte om problemet krever implementering av sensorer, hva som må måles, hvordan det skal måles, og hvordan de skal teste de potensielle sensorkonseptene. Basert på ti prosjekter og ti tilhørende vitenskapelige publikasjoner, presenterer denne oppgaven innsikt fra observasjoner innen relevante problemstillinger fra sensorteknologi og praksisser innen prototyping og protype testing: Egenskapene og utfordringene til komplekse sensorproblemer i the fuzzy front end utforskes, mulighets skapende prototypeatferd i løsingen av komplekse sensorproblemer, samt verktøy som muliggjør utforskende prototyping av komplekse sensorproblemer i the fuzzy front end. Basert på innsiktene, presenterers oppgavens resultater som åtte hypoteser som kan tjene som utgangspunkt for videre forskning. English abstract This thesis is addressed to researchers and product developers and provides insights on the solving of complex sensor problems in the fuzzy front end of product development. Sensors bridge physical phenomena and computational processing in cyber-physical systems and entail multidisciplinary practices in their application. As such, projects seeking novel and disruptive innovations in the fuzzy front end through sensors are often complex. Researchers and developers need to gauge whether the problem calls for the implementation of sensors, what to sense, how to sense it, and how to test the proposed sensor concepts. Based on ten projects and ten accompanying scientific publications, this thesis presents insights from practical examples for relevant topics within sensor technologies, prototyping practices, and prototype testing practices. Insights are generated on the characteristics and challenges of complex sensor problems in the fuzzy front end, enabling prototyping behaviors for solving complex sensor problems and tools for enabling explorative prototyping of complex sensor problems in the fuzzy front end. Based on the insights, the thesis presents the results as eight hypotheses that may serve as a starting point for further research.

In search for more efficient propulsion through water, many methods for improving on the existing hydrofoil and propeller designs we use today have been suggested, the topics of adaptive hydrofoils and propulsion systems is increasingly popular. A large portion of all world trade happens by sea, and even incremental improvements in propulsive efficiencies can have big economic and environmental impacts. Many researchers have looked to nature to find answers as to how to more efficiently use and manipulate water for propulsion and maneuvering. In this master s thesis I investigate the mechanisms that enables fish to use flows actively, and efficiently, to improve the capabilities of adaptive hydrofoils through sensory inputs. The thesis is based on the work done in my pre-master s thesis into the effects of Kármán gaiting, where fish use alternating vortices shed from obstructions in flows to generate forward momentum and is a response to the limited capabilities I found in the field of high density, non-intrusive/flow-obstructive, flow sensing at the surface of bodies and hydrofoils, such that correct adaptive movements can be made. I investigate different ways to sense flows along the skin of hydrofoils suspended in flowing water through prototyping and comparing solutions. Through comparison the piezo resistive effect of carbon fibers mixed with rubber silicone showed superior capabilities in detecting pressure changes as well as its ability to be easily imbedded and cast into flexible hydrofoils. The composite was further investigated in its capabilities in flow detection, through expanding the amount of datapoints with multiplexers to generate bigger pictures of the flow and enabling tendencies and pressure gradients to be seen. A water tunnel was run at different flow velocities of 0.04m/s and 0.1m/s, both free flowing and altered to generate alternating Kármán vortex streets. Two silicone hydrofoils were fitted with 64 sensors each. At 0.1m/s the Kármán flow generated cyclic behaviors in the forward-facing sensors in one of the hydrofoils, that directly corresponded with the observed and calculated shedding frequency. A dynamic neural network was further able to distinguish differences between all flow scenarios in separate data from the same calibrations and setups that were used in the training sets. The carbon fiber rubber silicone sensor shows similar piezo resistive properties as the popular carbon nanocomposite-silicone sensors, but the ease of manufacturing and low cost of the carbon fiber sensor could open up new possibilities and implementation in areas where such carbon nanocomposite sensors have not yet been deployed.