Abstract. In this “positioning” we discuss current developments, possibilities and challenges around working with film in and for geography. We describe possibilities that certain conscious and collaborative ways of employing film offer: They point beyond film analysis and are more than a mere add-on to communicate research results, but rather can stimulate new forms of reflexivity and creativity along different steps of research and teaching processes. We further show how the emergence of new digital and physical platforms can enable and support exchange on film and other digital media, using the example of our new media laboratory (mLab) at the University of Bern.

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Additive manufacturing processes have recently been used more frequently since they offer high design freedom and easy individualization of components. The processes have been optimized to improve mechanical performance of the manufactured parts. Nevertheless, properties of components made by means of injection molding could not be reached yet. In the study at hand, ultrasonic phase spectroscopy (UPS) is used to compare the elastic properties of acrylonitrile butadiene styrene specimens manufactured by injection molding, by fused filament fabrication, and the Arburg plastic freeforming process. UPS allows a nondestructive and prompt determination of the elastic modulus and allows evaluation of the mechanical properties in every direction in space. In the end, results of UPS are compared with properties derived by uniaxial tensile tests to validate UPS as a test method for the determination of the mechanical properties of polymers. Regardless of the manufacturing process, an approximately linear dependence of the elastic moduli on the density can be determined. Furthermore, the quasistatic properties of the injection molded samples consistently exhibit the mechanical properties of the other samples by at least 10%.

Shape memory alloys (SMA) stand out due to the ability that they can be deformed and then return to their initial shape by heating. This process results in a high actuation energy density. All SMA manufacturing methods, regardless of which matrix material is used, result in heat input into the SMA, which could induce a phase transformation and therefore disable the actuator function. In this regard, options to increase the transition temperatures of NiTi alloys above the processing temperatures are fundamental. In this study, the influence of the pre-tension on the transformation temperatures of SMA wires was investigated as a way to prevent phase transformation due to heat impact during the production of SMA-polymer-actuators. Applying a pre-tension of 400 MPa to the NiTi wire, the austenite start temperature could be increased by a factor of 1.9 whereas it could be increased by a factor of 2.2 with a pre-tension of 550 MPa. Therefore, after preloading the wires, a phase transformation should not be induced when the wire contacts the polymer droplets. However, the shift of the phase transformation has to be further investigated.