Open Access

Laser cutters are 2D tools, but their speed and compatibility with a variety of affordable materials also makes them a frequent choice to create 3D objects. We propose CutCAD, a tool to easily construct simple 3D objects from 2D faces, inspired by the process of paper modeling and magnetic construction kits. The user creates her 3D model by drawing or loading existing 2D shapes, and connecting their edges in the software. CutCAD then automatically resolves the resulting constraints, and folds the faces up into a 3D model that is previewed live. CutCAD also automatically creates the required finger joints based on thickness of the material and dihedral angles, for smooth assembly. Cutouts are easy to add by importing their outlines as vector drawings, and placing them onto faces. After the faces have been cut, CutCAD provides assembly instructions. Observations and feedback from using CutCAD show the resulting process to be easier to understand than traditional 3D modelling. CutCAD is open-source, and has been downloaded over 2,000 times.

Textile interfaces can be ubiquitously integrated into the fabrics that already surround us. So far, existing interfaces transfer concepts, such as buttons and sliders, to the textile domain without leveraging the affordances and qualities of fabric. This paper presents Grabrics, a two-dimensional textile sensor that is manipulated by grabbing a fold and moving it between your fingers. Grabrics can be integrated invisibly into everyday clothing or into textile objects, like a living room sofa, while minimizing accidental activation. We describe the construction and the fold-based interaction technique of our Grabrics sensor. A preliminary study shows that Grabrics can be folded and manipulated from any arbitrary position, and it can detect 2D stroke gestures.

20 years after the successful ground deployment test of a (20 m) 2 solar sail at DLR Cologne, and in the light of the upcoming U.S. NEAscout mission, we provide an overview of the progress made since in our mission and hardware design studies as well as the hardware built in the course of our solar sail technology development. We outline the most likely and most efficient routes to develop solar sails for useful missions in science and applications, based on our developed `now-term' and near-term hardware as well as the many practical and managerial lessons learned from the DLR-ESTEC Gossamer Roadmap. Mission types directly applicable to planetary defense include single and Multiple NEA Rendezvous ((M)NR) for precursor, monitoring and follow-up scenarios as well as sail-propelled head-on retrograde kinetic impactors (RKI) for mitigation. Other mission types such as the Displaced L1 (DL1) space weather advance warning and monitoring or Solar Polar Orbiter (SPO) types demonstrate the capability of near-term solar sails to achieve asteroid rendezvous in any kind of orbit, from Earth-coorbital to extremely inclined and even retrograde orbits. Some of these mission types such as SPO, (M)NR and RKI include separable payloads. For one-way access to the asteroid surface, nanolanders like MASCOT are an ideal match for solar sails in micro-spacecraft format, i.e. in launch configurations compatible with ESPA and ASAP secondary payload platforms. Larger landers similar to the JAXA-DLR study of a Jupiter Trojan asteroid lander for the OKEANOS mission can shuttle from the sail to the asteroids visited and enable multiple NEA sample-return missions. The high impact velocities and re-try capability achieved by the RKI mission type on a final orbit identical to the target asteroid's but retrograde to its motion enables small spacecraft size impactors to carry sufficient kinetic energy for deflection.

Learning to play the transverse flute is not an easy task, at least not for everyone. Since the flute does not have a reed to resonate, the player must provide a steady, focused stream of air that will cause the flute to resonate and thereby produce sound. In order to achieve this, the player has to be aware of the embouchure position to generate an adequate air jet. For a beginner, this can be a difficult task due to the lack of visual cues or indicators of the air jet and lips position. This paper attempts to address this problem by presenting an augmented flute that can make the gestures related to the embouchure visible and measurable. The augmented flute shows information about the area covered by the lower lip, estimates the lip hole shape based on noise analysis, and it shows graphically the air jet direction. Additionally, the augmented flute provides directional and continuous feedback in real time, based on data acquired by experienced flutists.

Audio augmented reality systems overlay the physical world with a virtual audio space. Today's smartphones provide enough processing power to create the impression of virtual sound sources being located in the real world. To achieve this, information about the user's location and orientation is necessary which requires additional hardware. In a real-world installation, however, we observed that instead of turning their head to localize sounds, users tend to turn their entire body. Therefore, we suggest to simply measure orientation of the user's body - or even just the mobile device she is holding - to generate the spatial audio. To verify this approach, we present two studies: Our first study in examines the user's head, body, and mobile device orientation when moving through an audio augmented reality system in a lab setting. Our second study analyzes the user experience in a real-world installation when using head, body, or device orientation to control the audio spatialization. We found that when navigating close to sound sources head tracking is necessary, but that it can potentially be replaced by device tracking in larger or more explorative usage scenarios. These findings help reduce the technical complexity of mobile audio augmented reality systems (MAARS), and enable their wider dissemination as mobile software-only apps.