In recent years, soft materials have seen increased prevalence in the design of robotic systems and wearables capable of addressing the needs of individuals living with disabilities. In particular, pneumatic artificial muscles (PAMs) have readily been employed in place of electromagnetic actuators due to their ability to produce large forces and motions, while still remaining lightweight, compact, and flexible. Due to the inherent nonlinearity of PAMs however, additional external or embedded sensors must be utilized in order to effectively control the overall system. In the case of external sensors, the bulkiness of the overall system is increased, which places limits on the system’s design. Meanwhile, the traditional cylindrical form factor of PAMs limits their ability to remain compact and results in overly complex fabrication processes when embedded fibers and/or sensing elements are required to provide efficient actuation and control. In order to overcome these limitations, this thesis proposed the design of flat pneumatic artificial muscles (FPAMs) capable of being fabricated using a simple layered manufacturing process, in which water-soluble masks were utilized to create collapsed air chambers. Furthermore, hyperelastic deformation models were developed to approximate the mechanical performance of the FPAMs and were verified through experimental characterization. The feasibility of these design techniques to meet the requirements of human centered applications, including the suppression of hand tremors and catheter ablation procedures, was explored and the potential for these soft actuation systems to act as solutions in other real world applications was demonstrated. We expect the design, fabrication, and modeling techniques developed in this thesis to aid in the development of future wearable devices and motivate new methods for researchers to employ soft pneumatic systems as solutions in human-centered applications.

Centrala venösa infarter används inom vården för att administrera läkemedel, ge parenteral nutrition och för blodprovstagning. Indikationer på att en patient behöver en central venös infart är att patienten behöver akut vård eller långvarig intravenös administrering av läkemedel. Många av dessa patienter behöver dessutom genomgå undersökningar via datortomografen (DT), där kontrastmedel kan krävas för att undersökningen ska kunna utföras. Syfte: Syftet med litteraturöversiktet var att sammanställa kunskap om centrala venösa infarters användbarhet vid administrering av kontrastmedel i samband med DT undersökningar. Metod: En allmän litteraturöversikt som baseras på tolv kvantitativa artiklar. Resultat: I de tolv artiklarna så uppmärksammades fyra kategorier som syftar till användbarheten: Tryck och Flödeshastigheter, Kateterspetsläge, Efterspolning och Diagnostisk bildkvalitet. Flera av studierna visade på kateterspetsförskjutning i samband med en kontrastmedelsinjektion med tryckspruta på DT. Tre av de fyra studier som kontrollerade bildkvalitet visade på bra diagnostisk bildkvalitet. Slutsats: Centrala venösa infarter är användbara vid administrering av kontrastmedel under datortomografiundersökningar under förutsättning att röntgensjuksköterskan har rätt kunskap om användandet av dem. Nationella riktlinjer behövs för att underlätta röntgensjuksköterskans arbete med dem så att hanteringen av dem utförs patientsäkert. / Central venous access is used in healthcare for drug administration, blood sampling, and providing parenteral nutrition. Indications for a patient needing a central venous access are either that a patient needs urgent care or prolonged intravenous administration of drugs. Many of these patients also need to undergo examinations via computed tomography (CT), where contrast agents may be required for the examination to be performed. Purpose: The purpose of the literature review was to compile knowledge about the usability of central venous access during the administration of contrast agents in connection with CT examinations. Method: A general literature review based on twelve quantitative articles was performed. Result: In the twelve articles, four categories were observed with the aim being usefulness: Pressure and Flow Rates, Catheter Tip position, Flushing and also Diagnostic Image Quality. Several of the studies showed catheter tip displacement being in connection with a contrast injection of a syringe during the CT examinations. Three of the four studies that controlled image quality showed good diagnostic image quality. Conclusions: Central venous access is useful in the administration of contrast agents during computed tomography examinations, provided that the radiographer has the correct knowledge of their use. National guidelines are needed to facilitate the radiographers work with them so that their usability is carried out with patient safety in mind.