Turn-by-wire: Computationally mediated physical fabrication

Advances in digital fabrication have simultaneously created new capabilities while reinforcing outdated workflows that constrain how, and by whom, these fabrication tools are used. In this paper, we investigate how a new class of hybrid-controlled machines can collaborate with novice and expert users alike to yield a more lucid making experience. We demonstrate these ideas through our system, Turn-by-Wire. By combining the capabilities of a traditional lathe with haptic input controllers that modulate both position and force, we detail a series of novel interaction metaphors that invite a more fluid making process spanning digital, model-centric, computer control, and embodied, adaptive, human control. We evaluate our system through a user study and discuss how these concepts generalize to other fabrication tools

LightSense: enabling spatially aware handheld interaction devices

devices. The outside-in approach tracks the light source and streams the data to the phone over Bluetooth. a) A wall-mounted map with embedded light sensors provides hotspot tracking. b) A table-top setup tracks the phone with a camera through a diffused glass surface. c) The spatially aware device augments a physical map with a detailed interactive road map of the area of interest. The vision of spatially aware handheld interaction devices has been hard to realize. The difficulties in solving the general tracking problem for small devices have been addressed by several research groups and examples of issues are performance, hardware availability and platform independency. We present Light-Sense, an approach that employs commercially available components to achieve robust tracking of cell phone LEDs, without any modifications to the device. Cell phones can thus be promoted to interaction and display devices in ubiquitous installations of systems such as the ones we present here. This could enable a new generation of spatially aware handheld interaction devices that would unobtrusively empower and assist us in our everyday tasks. CR Categories: H.5.1 [Multimedia Information Systems]: Artificial, augmented, and virtual realities; H.5.2. [User Interfaces]: Graphical user interfaces, Input devices and strategies; I.3.6 [Methodology and Techniques]: Interaction techniques

A Survey on Energy Efficient Network Coding for Multi-hop Routing in Wireless Sensor Networks

AbstractNetwork coding consists of intelligently aggregating data packets by means of binary or linear combinations. Recently, network coding has been proposed as a complementary solution for energy efficient multi-hop routing in Wireless Sensor Networks (WSNs). This is because network coding, through the aggregation of packets, considerably reduces the number of transmissions throughout the network. Although numerous network coding techniques for energy efficient routing have been developed in the literature, not much is known about a single survey article reporting on such energy efficient network coding within multi-hop WSNs. As a result, this paper addresses this gap by first classifying and discussing the recent developed energy efficient network coding techniques. The paper then identifies and explains open research opportunities based on analysis of merits of such techniques. This survey aims at providing the reader with a brief and concise idea on the current state-of-art research on network coding mainly focusing on its applications for energy efficient WSNs

SpaceTop: integrating 2D and spatial 3D interactions in a see-through desktop environment

SpaceTop is a concept that fuses spatial 2D and 3D interactions in a single workspace. It extends the traditional desktop interface with interaction technology and visualization techniques that enable seamless transitions between 2D and 3D manipulations. SpaceTop allows users to type, click, draw in 2D, and directly manipulate interface elements that float in the 3D space above the keyboard. It makes it possible to easily switch from one modality to another, or to simultaneously use two modalities with different hands. We introduce hardware and software configurations for co-locating these various interaction modalities in a unified workspace using depth cameras and a transparent display. We describe new interaction and visualization techniques that allow users to interact with 2D elements floating in 3D space. We present the results from a preliminary user study that indicates the benefit of such hybrid workspaces

inFORM: Dynamic Physical Affordances and Constraints through Shape and Object Actuation

Past research on shape displays has primarily focused on rendering content and user interface elements through shape output, with less emphasis on dynamically changing UIs. We propose utilizing shape displays in three different ways to mediate interaction: to facilitate by providing dynamic physical affordances through shape change, to restrict by guiding users with dynamic physical constraints, and to manipulate by actuating physical objects. We outline potential interaction techniques and introduce Dynamic Physical Affordances and Constraints with our inFORM system, built on top of a state-of-the-art shape display, which provides for variable stiffness rendering and real-time user input through direct touch and tangible interaction. A set of motivating examples demonstrates how dynamic affordances, constraints and object actuation can create novel interaction possibilities.National Science Foundation (U.S.). Graduate Research Fellowship (Grant 1122374)Swedish Research Council (Fellowship)Blanceflor Foundation (Scholarship

Improved Resource Allocation for TV White Space Network Based on Modified Firefly Algorithm

There is continued increased demand for dynamic spectrum access of TV White Spaces (TVWS) due to growing need for wireless broadband. Some of the use cases such as cellular (2G/3G/4G/5G) access to TVWS may have a high density of users that want to make use of TVWS. When there is a high density of secondary users (SUs) in a TVWS network, there is possibility of high interference among SUs that exceeds the desired threshold and also harmful interference to primary users (PUs). Optimization of resource allocation (power and spectrum allocation) is therefore necessary so as to protect PUs against harmful interference and to reduce the level of interference among SUs. Existing resource allocation optimization algorithms for a TVWS network ignore adjacent channel interference, interference among SUs or apply greedy algorithms which result in sub-optimal resource allocation. In this paper we propose an improved resource allocation algorithm based on continuous-binary firefly algorithm. Simulation is done using Matlab. Simulation results show that the proposed algorithm improves the SU sum throughput and SU signal to interference noise(SINR) ratio in the secondary network

Improved timing recovery in wireless mobile receivers

The problem of timing recovery in wireless mobile receiver systems is critical. This is partly because timing recovery functions must follow rapid parameter changes inherent in mobile systems and partly because both bandwidth and power must be conserved in low signal to noise ratio communication channels. The ultimate goal is therefore to achieve a low bit error rate on the recovered information for improving QoS provisioning to terminal mobile users. Traditional timing recovery methods have over-relied on phase-locked loops for timing information adjustment. However, associated schemes do not exploit code properties. This leads to synchronization difficulties in digital receivers separated from transmitters by lossy channels. In this paper we present a soft timing phase estimation algorithm for wireless mobile receivers in low signal to noise ratios. In order to develop a bandwidth and power efficient timing recovery method for wireless mobile receivers, a raised cosine filter and a multilevel phase shift keying modulation scheme are implemented and no clock signals are transmitted to the receiver. In the proposed method, the receiver exploits the soft decisions computed at each turbo decoding iteration to provide reliable estimates of a soft timing signal, which in turn, improves the decoding time. The derived method, based on sequential minimization techniques, approaches the theoretical Cramer-Rao bound with unbiased estimates within a few iterations.Key Words: discrete polyphase matched filters, maximum likelihood estimators, iterative turbo receivers, log-MAP b

Physical Telepresence: Shape Capture and Display for Embodied, Computer-mediated Remote Collaboration

We propose a new approach to Physical Telepresence, based on shared workspaces with the ability to capture and remotely render the shapes of people and objects. In this paper, we describe the concept of shape transmission, and propose interaction techniques to manipulate remote physical objects and physical renderings of shared digital content. We investigate how the representation of user's body parts can be altered to amplify their capabilities for teleoperation. We also describe the details of building and testing prototype Physical Telepresence workspaces based on shape displays. A preliminary evaluation shows how users are able to manipulate remote objects, and we report on our observations of several different manipulation techniques that highlight the expressive nature of our system.National Science Foundation (U.S.). Graduate Research Fellowship Program (Grant No. 1122374

Optimal Control of Transmission Power Management in Wireless Backbone Mesh Networks

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