Gestures are a promising candidate as an input modality for ambient computing where conventional input modalities such as touchscreens are not available. Existing works have focused on gesture recognition using image sensors. However, their cost, high battery consumption, and privacy concerns made cameras challenging as an always-on solution. This paper introduces an efficient gesture recognition technique using a miniaturized 60 GHz radar sensor. The technique recognizes four directional swipes and an omni-swipe using a radar chip (6.5 × 5.0 mm) integrated into a mobile phone. We developed a convolutional neural network model efficient enough for battery powered and computationally constrained processors. Its model size and inference time is less than 1/5000 compared to an existing gesture recognition technique using radar. Our evaluations with large scale datasets consisting of 558,000 gesture samples and 3,920,000 negative samples demonstrated our algorithm’s efficiency, robustness, and readiness to be deployed outside of research laboratories.

ZebraSense is a novel dual-sided woven touch sensor that can recognize and differentiate interactions on the top and bottom surfaces of the sensor. ZebraSense is based on an industrial multi-layer textile weaving technique, yet it enables a novel capacitive sensing paradigm, where each sensing element contributes to touch detection on both surfaces of the sensor simultaneously. Unlike the common "sensor sandwich" approach used in previous work, ZebraSense inherently minimizes the number of sensing elements, which drastically simplifies both sensor construction and its integration into soft goods, while preserving maximum sensor resolution. The experimental evaluation confirmed the validity of our approach and demonstrated that ZebraSense is a reliable, efficient, and accurate solution for detecting user gestures in various dual-sided interaction scenarios, allowing for new use cases in smart apparel, home decoration, toys, and other textile objects.

Interactions and connectivity is increasingly expanding to shared objects and environments, such as furniture, vehicles, lighting, and entertainment systems. For transparent personalization in such contexts, we see an opportunity for embedded recognition, to complement traditional, explicit authentication. We introduce Zensei, an implicit sensing system that leverages bio-sensing, signal processing and machine learning to classify uninstrumented users by their body's electrical properties. Zensei could allow many objects to recognize users. E.g., phones that unlock when held, cars that automatically adjust mirrors and seats, or power tools that restore user settings. We introduce wide-spectrum bioimpedance hardware that measures both amplitude and phase. It extends previous approaches through multi-electrode sensing and high-speed wireless data collection for embedded devices. We implement the sensing in devices and furniture, where unique electrode configurations generate characteristic profiles based on user's unique electrical properties. Finally, we discuss results from a comprehensive longitudinal 22-day data collection experiment with 46 subjects. Our analysis shows promising classification accuracy and low false acceptance rate.

This paper explores the social meaning of clothing-based displays of biosignals. How do friends make sense of their own and each other's skin conductance display in the context of a conversation? We developed Hint, a dynamic thermochromic t-shirt whose ambiguous pattern changes color when its wearer's skin conductance increases, an indication of sudden arousal. We investigated how pairs of friends each wearing the shirt conversed and interpreted the display. Participants shared a broad range of interpretations; e.g., joy and embarrassment were associated with an increase in skin conductance. Additionally, participants expressed desires for their skin conductance display to help validate their feelings and show emotional engagement with others. We explore ambiguity in the context of clothing-based information displays and discuss how skin conductance display became part of social performance in our study. From there, we suggest framing biosignals as social cues along with facial expression, gestures, etc., and begin to question what design territories this might uncover.

This paper explores the role dynamic textile displays play in relation to personal style: What does it mean to wear computationally responsive clothing and why would one be motivated to do so? We developed a novel textile display technology, called Ebb, and created several woven and crochet fabric swatches that explored clothing-specific design possibilities. We engaged fashion designers and non-designers in imagining how Ebb would integrate into their design practice or personal style of dressing. Participants evaluated the appeal and utility of clothing-based displays according to a very different set of criteria than traditional screen-based computational displays. Specifically, the slowness, low-resolution, and volatility of Ebb tended to be seen as assets as opposed to technical limitations in the context of personal style. Additionally, participants envisioned various ways that ambiguous, ambient, and abstract displays of information could prompt new experiences in their everyday lives. Our paper details the complex relationships between display and personal style and offers a new design metaphor and extension of Gaver et al.'s original descriptions of ambiguity in order to guide the design of clothing-based displays for everyday life.

Project Jacquard presents manufacturing technologies that enable deploying invisible ubiquitous interactivity at scale. We propose novel interactive textile materials that can be manufactured inexpensively using existing textile weaving technology and equipment.

This paper proposes a novel machine learning architecture, specifically designed for radio-frequency based gesture recognition. We focus on high-frequency (60]GHz), short-range radar based sensing, in particular Google's Soli sensor. The signal has unique properties such as resolving motion at a very fine level and allowing for segmentation in range and velocity spaces rather than image space. This enables recognition of new types of inputs but poses significant difficulties for the design of input recognition algorithms. The proposed algorithm is capable of detecting a rich set of dynamic gestures and can resolve small motions of fingers in fine detail. Our technique is based on an end-to-end trained combination of deep convolutional and recurrent neural networks. The algorithm achieves high recognition rates (avg 87%) on a challenging set of 11 dynamic gestures and generalizes well across 10 users. The proposed model runs on commodity hardware at 140 Hz (CPU only).

This paper presents Soli , a new, robust, high-resolution, low-power, miniature gesture sensing technology for human-computer interaction based on millimeter-wave radar. We describe a new approach to developing a radar-based sensor optimized for human-computer interaction, building the sensor architecture from the ground up with the inclusion of radar design principles, high temporal resolution gesture tracking, a hardware abstraction layer (HAL), a solid-state radar chip and system architecture, interaction models and gesture vocabularies, and gesture recognition. We demonstrate that Soli can be used for robust gesture recognition and can track gestures with sub-millimeter accuracy, running at over 10,000 frames per second on embedded hardware.

We propose technology for designing and manufacturing interactive 3D printed speakers. With the proposed technology, sound reproduction can easily be integrated into vari-ous objects at the design stage and little assembly is required. The speaker can take the shape of anything from an abstract spiral to a rubber duck, opening new opportunities in product design. Furthermore, both audible sound and inaudible ultrasound can be produced with the same design, allowing for identifying and tracking 3D printed objects in space using common integrated microphones. The design of 3D printed speakers is based on electrostatic loudspeaker technology first explored in the early 1930s but not broadly applied until now. These speakers are simpler than common electromagnetic speakers, while allowing for sound reproduction at 60 dB levels with arbitrary directivity ranging from focused to omnidirectional. Our research of 3D printed speakers contributes to the growing body of work exploring functional 3D printing in interactive applications.

From the dawn of the industrial revolution and establishment of mass production the world has been fixed and immutable. The objects and devices around us were designed by engineers, manufactured in factories, sold in stores and brought to our homes and offices to serve the purpose that they had been made for. Our roles were that of passive consumers. Recently, however, we have come to expect that our objects and environments are interactive, engaging and hackable anytime and anywhere. We are no longer passive consumers. With new rapid prototyping tools, open source software, readily available sensors and microprocessors, novel materials, 3D printers and printed electronics our world can be hacked, twisted, connected, re-connected and extended with functionality that it is not supposed to have. We can make living plants play digital music and human bodies transmit sound, we can build touch screens on water, extend our world by 3D printing whatever we need, create virtual objects that we can feel in free air with bare hands and produce electrical energy from ordinary paper. Everyday physical objects, both living and artificial, and entire environments can be made interactive, responsive and digital. Never before in our collective history have we as individuals had so much power to re-make the world around us, enhance it with new experiences and functionalities that educate, delight, entertain and make our lives better in countless ways. And most of them are yet to be invented. In this talk I will look back at the relation of digital technology and physical world, speculate about it's future and discuss some of the recent explorations that myself and my group have been conducting in merging digital computing and physical environments. Some of the topics include new technologies for tactile augmentation, free-air haptics, deformable and compliant computers, ad-hoc sensor augmentation, biologically inspired interfaces, energy harvesting and others. The talk will cover both early projects that I conducted at Sony Corporation and current research efforts by the Interaction Group at Disney Research, Pittsburgh.

We present a technology for designing curved display surfaces that can both display information and sense two dimensions of human touch. It is based on 3D printed optics, where the surface of the display is constructed as a bundle of printed light pipes, that direct images from an arbitrary planar image source to the surface of the display. This effectively decouples the display surface and image source, allowing to iterate the design of displays without requiring changes to the complex electronics and optics of the device. In addition, the same optical elements also direct light from the surface of the display back to the image sensor allowing for touch input and proximity detection of a hand relative to the display surface. The resulting technology is effective in designing compact, efficient displays of a small size; this has been applied in the design of interactive animated eyes.

We present a new energy harvesting technology that generates electrical energy from a user's interactions with paper-like materials. The energy harvesters are flexible, light, and inexpensive, and they utilize a user's gestures such as tapping, touching, rubbing and sliding to generate electrical energy. The harvested energy is then used to actuate LEDs, e-paper displays and various other devices to create novel interactive applications, such as enhancing books and other printed media with interactivity.

We present a tactile-rendering algorithm for simulating 3D geometric features, such as bumps, on touch screen surfaces. This is achieved by modulating friction forces between the user's finger and the touch screen, instead of physically moving the touch surface. We proposed that the percept of a 3D bump is created when local gradients of the rendered virtual surface are mapped to lateral friction forces. To validate this approach, we first establish a psychophysical model that relates the perceived friction force to the controlled voltage applied to the tactile feedback device. We then use this model to demonstrate that participants are three times more likely to prefer gradient force profiles than other commonly used rendering profiles. Finally, we present a generalized algorithm and conclude the paper with a set of applications using our tactile rendering technology.

We present Lumitrack, a novel motion tracking technology that uses projected structured patterns and linear optical sensors. Each sensor unit is capable of recovering 2D location within the projection area, while multiple sensors can be combined for up to six degree of freedom (DOF) tracking. Our structured light approach is based on special patterns, called m-sequences, in which any consecutive sub-sequence of m bits is unique. Lumitrack can utilize both digital and static projectors, as well as scalable embedded sensing configurations. The resulting system enables high-speed, high precision, and low-cost motion tracking for a wide range of interactive applications. We detail the hardware, operation, and performance characteristics of our approach, as well as a series of example applications that highlight its immediate feasibility and utility.

Until recently, the ways in which we interacted with computers were limited by the flat, rigid and rectangular form factors of cathode-ray tubes and liquid crystal displays. Technical limitations forced user interfaces into boxes, limiting interactions to 2D pointing and keyboard input. With technological advances in flexible sensor and display technologies, we are experiencing a new revolution in human–computer interaction (HCI): one in which user interfaces can be worn on the body as if they were cloth, used in the office as if they were paper and used in architecture as if they were wallpapers (Co and Pashenkov, 2008; Buechley and Mellis, 2010; Lahey et al., 2011). Rather than being rigid and static, the user interfaces of tomorrow will be able to have a shape that accommodates the user’s context and fits the data on display. For instance, if a user wants to explore geographic information, they can use a spherical display that does not require distortion of the earth projection (Stevenson, 2010). When reading an interactive map, users can extend their mobile’s screen real estate by unfolding their pocket-size flexible e-paper display.

AIREAL is a novel haptic technology that delivers effective and expressive tactile sensations in free air, without requiring the user to wear a physical device. Combined with interactive computers graphics, AIREAL enables users to feel virtual 3D objects, experience free air textures and receive haptic feedback on gestures performed in free space. AIREAL relies on air vortex generation directed by an actuated flexible nozzle to provide effective tactile feedback with a 75 degrees field of view, and within an 8.5cm resolution at 1 meter. AIREAL is a scalable, inexpensive and practical free air haptic technology that can be used in a broad range of applications, including gaming, mobile applications, and gesture interaction among many others. This paper reports the details of the AIREAL design and control, experimental evaluations of the device's performance, as well as an exploration of the application space of free air haptic displays. Although we used vortices, we believe that the results reported are generalizable and will inform the design of haptic displays based on alternative principles of free air tactile actuation.

Touché proposes a novel Swept Frequency Capacitive Sensing technique that can not only detect a touch event, but also recognize complex configurations of the human hands and body. Such contextual information significantly enhances touch interaction in a broad range of applications, from conventional touchscreens to unique contexts and materials. For example, in our explorations we add touch and gesture sensitivity to the human body and liquids. We demonstrate the rich capabilities of Touché with five example setups from different application domains and conduct experimental studies that show gesture classification accuracies of 99% are achievable with our technology.

Touché proposes a novel Swept Frequency Capacitive Sensing technique that can not only detect a touch event, but also recognize complex configurations of the human hands and body. Such contextual information significantly enhances touch interaction in a broad range of applications, from conventional touchscreens to unique contexts and materials. For example, in our explorations we add touch and gesture sensitivity to the human body and liquids. We demonstrate the rich capabilities of Touché with five example setups from different application domains and conduct experimental studies that show gesture classification accuracies of 99% are achievable with our technology.

Advances in new materials and manufacturing techniques are rapidly blending the computational and physical worlds. With every new turn in technology development - e.g., discovering a novel "smart" material, inventing a more efficient manufacturing process or designing a faster microprocessor - there are new and exciting ways to take user interfaces away from the screen and blend them into our living spaces and everyday objects, making them more responsive, intelligent and adaptive. As the world around us becomes increasingly infused with technology, the user interfaces and computers themselves will disappear into the background, blending into the physical world around us. Thus, the old tried-and-true paradigms for designing interaction and interfaces must be re-evaluated, re-designed and, in some cases, even discarded to take advantage of the new possibilities that these cutting-edge technologies provide. While the challenges and opportunities are distinct, the fundamental goal remains the same: to provide for the effortless and effective consumption, control and transmission of information at any time and in any place, while delivering a unique experience that is only possible with these emerging technologies.

At present, touchscreens can differentiate multiple points of contact, but not who is touching the device. In this work, we consider how the electrical properties of humans and their attire can be used to support user differentiation on touchscreens. We propose a novel sensing approach based on Swept Frequency Capacitive Sensing, which measures the impedance of a user to the environment (i.e., ground) across a range of AC frequencies. Different people have different bone densities and muscle mass, wear different footwear, and so on. This, in turn, yields different impedance profiles, which allows for touch events, including multitouch gestures, to be attributed to a particular user. This has many interesting implications for interactive design. We describe and evaluate our sensing approach, demonstrating that the technique has considerable promise. We also discuss limitations, how these might be overcome, and next steps.

We present an approach to 3D printing custom optical elements for interactive devices labelled Printed Optics. Printed Optics enable sensing, display, and illumination elements to be directly embedded in the casing or mechanical structure of an interactive device. Using these elements, unique display surfaces, novel illumination techniques, custom optical sensors, and embedded optoelectronic components can be digitally fabricated for rapid, high fidelity, highly customized interactive devices. Printed Optics is part of our long term vision for interactive devices that are 3D printed in their entirety. In this paper we explore the possibilities for this vision afforded by fabrication of custom optical elements using today's 3D printing technology.

REVEL is an augmented reality (AR) tactile technology that allows for change to the tactile feeling of real objects by augmenting them with virtual tactile textures using a device worn by the user. Unlike previous attempts to enhance AR environments with haptics, we neither physically actuate objects or use any force- or tactile-feedback devices, nor require users to wear tactile gloves or other apparatus on their hands. Instead, we employ the principle ofreverse electrovibrationwhere we inject a weak electrical signal anywhere on the user body creating an oscillating electrical field around the user's fingers. When sliding his or her fingers on a surface of the object, the user perceives highly distinctive tactile textures augmenting the physical object. By tracking the objects and location of the touch, we associate dynamic tactile sensations to the interaction context. REVEL is built upon our previous work on designing electrovibration-based tactile feedback for touch surfaces [Bau, et al. 2010]. In this paper we expand tactile interfaces based on electrovibration beyond touch surfaces and bring them into the real world. We demonstrate a broad range of application scenarios where our technology can be used to enhance AR interaction with dynamic and unobtrusive tactile feedback.

Tactile Brush is an algorithm that produces smooth, two-dimensional tactile moving strokes with varying frequency, intensity, velocity and direction of motion. The design of the algorithm is derived from the results of psychophysical investigations of two tactile illusions -- apparent tactile mo-tion and phantom sensations. Combined together they allow for the design of high-density two-dimensional tactile displays using sparse vibrotactile arrays. In a series of experiments and evaluations we demonstrate that Tactile Brush is robust and can reliably generate a wide variety of moving tactile sensations for a broad range of applications.

We present the MotionBeam metaphor for character interaction with handheld projectors. Our work draws from the tradition of pre-cinema handheld projectors that use direct physical manipulation to control projected imagery. With our prototype system, users interact and control projected characters by moving and gesturing with the handheld projector itself. This creates a unified interaction style where input and output are tied together within a single device. We introduce a set of interaction principles and present prototype applications that provide clear examples of the MotionBeam metaphor in use. Finally we describe observations and insights from a preliminary user study with our system.

In this paper we present three experiments to measure the control parameter space of apparent haptic motion using a variety of stimulation attributes and body sites. In Experiment 1 we measured the range of Stimulus Onset Asynchrony (SOA) that created the percept of continuous motion between two vibrating points on the dorsal forearm and on the back by varying the frequency, intensity and duration of stimulation. The SOA space for apparent motion varied with duration and body site but not with frequency and intensity of stimulation. In Experiment 2 we measured the SOA space for moving sensations when direction of motion and spacing between actuators were varied. On the forearm the SOA space was influenced by both the direction and spacing. However, on the back it was only affected by the direction of actuation. Finally, in Experiment 3 we measured the SOA space using four or more actuation points, creating two-dimensional apparent motion. The results of the present study are discussed in the context of designing haptic contents for movies, amusement rides and video games.

Advances in display, sensor and actuator technology are changing the field of TEI, and opening new research areas. While modern interfaces have been designed for traditional planar and static display devices, next-generation UI allow digital objects to change their shape and embed displays anywhere. Fitting into the paradigm of Organic User Interfaces, these developments require us to reexamine and reevaluate some of the basic design principles and interaction styles currently used. This Second International Workshop on Organic User Interfaces will bring together experts to discuss, brainstorm and prototype next generation of user interfaces.

We present a method for designing and constructing rugged and soft multi-point sensors. Interactions applied to a soft material are reduced to structural units of deformation. These structures can then be embedded and instrumented anywhere inside a soft sensor. This simplification lets us design complex, durable sensors in easily manufacturable ways. In particular, we present a construction method of layering electronics between silicone pours to easily create sensors for arbitrary combinations of these deformations. We present several prototype sensors and discuss applications including toys, games, and therapy.

We introduce SideBySide, a system designed for ad-hoc multi-user interaction with handheld projectors. SideBySide uses device-mounted cameras and hybrid visible/infrared light projectors to track multiple independent projected images in relation to one another. This is accomplished by projecting invisible fiducial markers in the near-infrared spectrum. Our system is completely self-contained and can be deployed as a handheld device without instrumentation of the environment. We present the design and implementation of our system including a hybrid handheld projector to project visible and infrared light, and techniques for tracking projected fiducial markers that move and overlap. We introduce a range of example applications that demonstrate the applicability of our system to real-world scenarios such as mobile content exchange, gaming, and education.

We present a new technology for enhancing touch interfaces with tactile feedback. The proposed technology is based on the electrovibration principle, does not use any moving parts and provides a wide range of tactile feedback sensations to fingers moving across a touch surface. When combined with an interactive display and touch input, it enables the design of a wide variety of interfaces that allow the user to feel virtual elements through touch. We present the principles of operation and an implementation of the technology. We also report the results of three controlled psychophysical experiments and a subjective user evaluation that describe and characterize users' perception of this technology. We conclude with an exploration of the design space of tactile touch screens using two comparable setups, one based on electrovibration and another on mechanical vibrotactile actuation.

In the last decade, the vision of future interfaces has shifted from virtual reality to augmented and tangible user interfaces (UI) where virtual and physical (or "bits and atoms") co-exist in harmony. Recently, a growing number of designers and researchers have been taking the next logical step: creating interfaces where physical, tangible elements are not merely dynamically coupled to the digital attributes and information, but are themselves dynamic, self-reconfigurable devices that can change their physical properties depending on the state of the interfaces, the user, or the environment.A combination of the actuation, self-configuration, and tangibility can expand and enhance the design of tangible interfaces. In this paper, we present an overview of the use of actuation in user interfaces and discuss the rationality of building actuated interfaces. We then discuss actuated interfaces in detail based on our experience designing Lumen shape displays. Work on actuated interfaces is still in its infancy, projects are few and far between, so we consider this paper an invitation to discussion and hope it can help stimulate further research in this area.

Gummi is an interaction technique and device concept based on physical deformation of a handheld device. The device consists of several layers of flexible electronic components, including sensors measuring deformation of the device. Users interact with this device by a combination of bending and 2D position control. Gummi explores physical interaction techniques and screen interfaces for such a device. Its graphical user interface facilitates a wide range of interaction tasks, focused on browsing of visual information. We implemented both hardware and software prototypes to explore and evaluate the proposed interaction techniques.Our evaluations have shown that users can grasp Gummi's key interaction principles within minutes. Gummi demonstrates promising possibilities for new interaction techniques and devices based on flexible electronic components.

We present the design, implementation, and informal evaluation of tactile interfaces for small touch screens used in mobile devices. We embedded a tactile apparatus in a Sony PDA touch screen and enhanced its basic GUI elements with tactile feedback. Instead of observing the response of interface controls, users can feel it with their fingers as they press the screen. In informal evaluations, tactile feedback was greeted with enthusiasm. We believe that tactile feedback will become the next step in touch screen interface design and a standard feature of future mobile devices.

This paper investigates the sense of touch as a channel for communicating with miniature handheld devices. We embedded a PDA with a TouchEngineTM --- a thin, miniature lower-power tactile actuator that we have designed specifically to use in mobile interfaces (Figure 1). Unlike previous tactile actuators, the TouchEngine is a universal tactile display that can produce a wide variety of tactile feelings from simple clicks to complex vibrotactile patterns. Using the TouchEngine, we began exploring the design space of interactive tactile feedback for handheld computers. Here, we investigated only a subset of this space: using touch as the ambient, background channel of interaction. We proposed a general approach to design such tactile interfaces and described several implemented prototypes. Finally, our user studies demonstrated 22% faster task completion when we enhanced handheld tilting interfaces with tactile feedback.

In its simplest form, reality is merely information that is presented or acquired. Mixed Reality (MR) is built around the integration of real world physical and computer generated virtual information. We do not use the term augmented reality (AR) because we view the merging of both worlds as a symbiosis, with desirable properties from each accentuated and complementing each other, rather than the enhancement of one with the other. Collaborative MR allows multiple participants to simultaneously share a physical space while being surrounded by a virtual space that is registered with the physical. Because the MR world inherits the properties of real and virtual worlds, it is rich with social context, spatial cues, and tangible objects from the real world as well as flexible digital information from virtual. We believe that Mixed Reality is a medium, largely unexplored, but very well suited for face-to-face collaboration.

This paper demonstrates how non-isomorphic rotational mappings and interaction techniques can be designed and used to build effective spatial 3D user interfaces. In this paper, we develop a mathematical framework allowing us to design non-isomorphic 3D rotational mappings and techniques, investigate their usability properties, and evaluate their user performance characteristics. The results suggest that non-isomorphic rotational mappings can be an effective tool in building high-quality manipulation dialogs in 3D interfaces, allowing our subjects to accomplish experimental tasks 13% faster without a statistically detectable loss in accuracy. The current paper will help interface designers to use non-isomorphic rotational mappings effectively.

The acceptance of virtual environment (VE) technology requires scrupulous optimization of the most basic interactions in order to maximize user performance and provide efficient and enjoyable virtual interfaces. Motivated by insufficient understanding of the human factors design implications of interaction techniques and tools for virtual interfaces, this paper presents results of a formal study that compared two basic interaction metaphors for egocentric direct manipulation in VEs, virtual hand and virtual pointer, in object selection and positioning experiments. The goals of the study were to explore immersive direct manipulation interfaces, compare performance characteristics of interaction techniques based on the metaphors of interest, understand their relative strengths and weaknesses, and derive design guidelines for practical development of VE applications.

Developing virtual reality (VR) applications which enable actual work over a period of time requires optimization of the most basic interactions, such as object manipulation, so that the immersed participant can concentrate on higher-level tasks rather than on lowlevel motor activities. This paper presents a framework and experimental testbed for studies of VR object manipulation techniques. The framework provides a systematic task analysis of immersive manipulation and suggests a user-specific non-Euclidean system for the measurement of VR spatial relationships. The Virtual Reality Manipulation Assessment Testbed (VRMAT) is a practical implementation of the framework and is a flexible tool allowing in-depth experimental studies of immersive manipulation. Pilot studies have been conducted to evaluate this framework and testbed and to establish a baseline for further development. Keywords: immersive virtual reality, VR user interfaces, VR manipulation techniques, user studies, experimen...

The Go-Go immersive interaction technique uses the metaphor of interactively growing the user’s arm and non-linear mapping for reaching and manipulating distant objects. Unlike others, our technique allows for seamless direct manipulation of both nearby objects and those at a distance.