Digital-is-Physical : How Functional Fabrication Disrupts Ubicomp Design Principles

Ubiquitous computing has long explored design through the conceptual separation of digital and physical materials. We describe how the emergence of the fabrication community in HCI will challenge these conceptual principles. The idea of digital material in ubicomp ‘hides’ lower level abstractions such as physical architectures and materials from designers. As new fabrication techniques make these abstractions accessible to makers, physical materials are being used to encode digital functionality. Form (traditionally physical) and function (traditionally digital) can be mutually expressed within material design. We outline how emerging printed electronics techniques will enable functional fabrication, current limitations and opportunities for end-user fabrication of functional devices, and implications for new principles that emphasise combined physical design of form and function

ProtoSpray: Combining 3D Printing and Spraying to Create Interactive Displays with Arbitrary Shapes

ProtoSpray is a fabrication method that combines 3D printing and spray coating, to create interactive displays of arbitrary shapes. Our approach makes novel use of 3D printed conductive channels to create base electrodes on 3D shapes. This is then combined with spraying active materials to produce illumination. We demonstrate the feasibility and benefits of this combined approach in 6 evaluations exploring different shaped topologies. We analyze factors such as spray orientations, surface topologies and printer resolutions, to discuss how spray nozzles can be integrated into traditional 3D printers. We present a series of ProtoSprayed objects demonstrating how our technique goes beyond existing fabrication techniques by allowing creation of displays on objects with curvatures as complex as a Mobius strip. Our work provides a platform to empower makers to use displays as a fabrication material.<br/

ProtoSpray: Combining 3D Printing and Spraying to Create Interactive Displays with Arbitrary Shapes

ProtoSpray is a fabrication method that combines 3D printing and spray coating, to create interactive displays of arbitrary shapes. Our approach makes novel use of 3D printed conductive channels to create base electrodes on 3D shapes. This is then combined with spraying active materials to produce illumination. We demonstrate the feasibility and benefits of this combined approach in 6 evaluations exploring different shaped topologies. We analyze factors such as spray orientations, surface topologies and printer resolutions, to discuss how spray nozzles can be integrated into traditional 3D printers. We present a series of ProtoSprayed objects demonstrating how our technique goes beyond existing fabrication techniques by allowing creation of displays on objects with curvatures as complex as a Mobius strip. Our work provides a platform to empower makers to use displays as a fabrication material.<br/

TRIPPy: Trailed Image Photometry in Python

Photometry of moving sources typically suffers from reduced signal-to-noise (SNR) or flux measurements biased to incorrect low values through the use of circular apertures. To address this issue we present the software package, TRIPPy: TRailed Image Photometry in Python. TRIPPy introduces the pill aperture, which is the natural extension of the circular aperture appropriate for linearly trailed sources. The pill shape is a rectangle with two semicircular end-caps, and is described by three parameters, the trail length and angle, and the radius. The TRIPPy software package also includes a new technique to generate accurate model point-spread functions (PSF) and trailed point-spread functions (TSF) from stationary background sources in sidereally tracked images. The TSF is merely the convolution of the model PSF, which consists of a moffat profile, and super sampled lookup table. From the TSF, accurate pill aperture corrections can be estimated as a function of pill radius with a accuracy of 10 millimags for highly trailed sources. Analogous to the use of small circular apertures and associated aperture corrections, small radius pill apertures can be used to preserve signal-to-noise of low flux sources, with appropriate aperture correction applied to provide an accurate, unbiased flux measurement at all SNR.Comment: 8 Figures, 11 Pages, Accepted to the Astronomical Journa