Pedro Lopes

University of Chicago | UC · Department of Computer Science

We propose a new way of eyes-free interaction for weara-bles. It is based on the user's proprioceptive sense, i.e., rather than seeing, hearing, or feeling an outside stimulus, users feel the pose of their own body. We have implemented a wearable device called Pose-IO that offers input and output based on proprioception. Users communicate with Pose...

We present impacto, a device designed to render the haptic sensation of hitting and being hit in virtual reality. The key idea that allows the small and light impacto device to simulate a strong hit is that it decomposes the stimulus: it renders the tactile aspect of being hit by tapping the skin using a solenoid; it adds impulse to the hit by thru...

We propose extending the affordance of objects by allowing them to communicate dynamic use, such as (1) motion (e.g., spray can shakes when touched), (2) multi-step processes (e.g., spray can sprays only after shaking), and (3) behaviors that change over time (e.g., empty spray can does not allow spraying anymore). Rather than enhancing objects dir...

Low-fidelity prototyping is so foundational to Human-Computer Interaction, appearing in most early design phases. So, how do experts prototype olfactory experiences? We interviewed eight experts and found that they do not because no process supports this. Thus, we engineered Smell & Paste, a low-fidelity prototyping toolkit. Designers assemble olfa...

Haptic devices allow us to feel virtual worlds through touch and forces; yet they are incompatible with haptics present in our everyday life. This urges us to re-think how to engineer a wave of new haptic devices for extended reality.

In our increasingly complex world, many objects in our environment do not readily afford their intended use case. From a designer’s viewpoint, the challenge then is to design for easily perceived utility. In this essay, we discuss a system to implement affordances on the user directly. We present the idea to leverage brain activity and actuation ha...

Force-feedback enhances digital touch by enabling users to share non-verbal aspects such as rhythm, poses, and so on. To achieve this, interfaces actuate the user’s to touch involuntarily (using exoskeletons or electrical-muscle-stimulation); we refer to this as computer-driven touch. Unfortunately, forcing users to touch causes a loss of their sen...

Objective Neural interfaces hold significant promise to implicitly track user experience. Their application in VR/AR simulations is especially favorable as it allows user assessment without breaking the immersive experience. In VR, designing immersion is one key challenge. Subjective questionnaires are the established metrics to assess the effectiv...

A stretchable pressure sensor is a necessary tool for perceiving physical interactions that take place on soft/deformable skins present in human bodies, prosthetic limbs, or soft robots. However, all existing types of stretchable pressure sensors have an inherent limitation, which is the interference of stretching with pressure sensing accuracy. He...

We propose a new class of haptic devices that provide haptic sensations by delivering liquid-stimulants to the user’s skin; we call this chemical haptics. Upon absorbing these stimulants, which contain safe and small doses of key active ingredients, receptors in the user’s skin are chemically triggered, rendering distinct haptic sensations. We iden...

We propose a new type of haptic actuator, which we call MagnetIO, that is comprised of two parts: one battery-powered voice-coil worn on the user’s fingernail and any number of interactive soft patches that can be attached onto any surface (everyday objects, user’s body, appliances, etc.). When the user’s finger wearing our voice-coil contacts any...

Everyday life hinges on smell, taste, and temperature-based experiences, from eating to detecting potential hazards (e.g., smell of rotten food, microbial threats, and non-microbial threats such as from hazardous gases) to responding to thermal behavioral changes. These experiences are formative as visceral, vital signals of information, and contri...

We demonstrate a new type of haptic actuator, which we call MagnetIO, that is comprised of two parts: one battery-powered voice-coil worn on the user's fingernail and any number of interactive soft patches that can be attached onto any surface (everyday objects, user's body, appliances, etc.). When the user's finger wearing our voice-coil contacts...

In the field of human-computer interaction, the term “integration” describes an emergent paradigm in which the human and the computer are tightly coupled. Our previous research has contributed to this paradigm through the design of “bodily integrated” systems, where the human body and the computing machinery are coupled in a way that allows bidirec...

We engineered an exoskeleton, which we call HandMorph, that approximates the experience of having a smaller grasping range. It uses mechanical links to transmit motion from the wearer's fingers to a smaller hand with five anatomically correct fingers. The result is that HandMorph miniaturizes a wearer's grasping range while transmitting haptic feed...

We explore the application of a wide range of sensory stimulation technologies to the area of sleep and dream engineering. We begin by emphasizing the causal role of the body in dream generation, and describe a circuitry between the sleeping body and the dreaming mind. We suggest that nearly any sensory stimuli has potential for modulating experien...

Human-Computer Integration (HInt) is an emerging paradigm in which computational and human systems are closely interwoven. Integrating computers with the human body is not new. however, we believe that with rapid technological advancements, increasing real-world deployments, and growing ethical and societal implications, it is critical to identify...

2020 ACM. Human-Computer Integration (HInt) is an emerging paradigm in which computational and human systems are closely interwoven. Integrating computers with the human body is not new. however, we believe that with rapid technological advancements, increasing real-world deployments, and growing ethical and societal implications, it is critical to...

Force feedback is said to be the next frontier in virtual reality (VR). Recently, with consumers pushing forward with untethered VR, researchers turned away from solutions based on bulky hardware (e.g., exoskeletons and robotic arms) and started exploring smaller portable or wearable devices. However, when it comes to rendering inertial forces, suc...

In this demonstration we enable preemptive force-feedback systems to speed up human reaction time without fully compromising the user's sense of agency. Typically these haptic systems speed up human reaction time by means of electrical muscle stimulation (EMS) or mechanical actuation (exoskeletons), which unfortunately, completely remove the users...

We enable preemptive force-feedback systems to speed up human reaction time without fully compromising the user's sense of agency. Typically these interfaces actuate by means of electrical muscle stimulation (EMS) or mechanical actuators; they preemptively move the user to perform a task, such as to improve movement performance (e.g., EMS-assisted...

Designing immersion is the key challenge in virtual reality; this challenge has driven advancements in displays, rendering and recently, haptics. To increase our sense of physical immersion, for instance, vibrotactile gloves render the sense of touching, while electrical muscle stimulation (EMS) renders forces. Unfortunately, the established metric...

Recent works have explained the principle of using ultrasonic transmissions to jam nearby microphones. These signals are inaudible to nearby users, but leverage "hardware nonlinearity" to induce a jamming signal inside microphones that disrupts voice recordings. This has great implications on audio privacy protection. In this work, we gain a deeper...

How can interactive devices connect with users in the most immediate and intimate way? This question has driven interactive computing for decades. Throughout the last decades, we witnessed how mobile devices moved computing into users’ pockets, and recently, wearables put computing in constant physical contact with the user’s skin. In both cases mo...

We provide attendees with a hands-on demonstration of several our interactive systems based on electrical muscle stimulation. These wearable devices allow attendees, for example, to transform their arms in interactive plotters, physically learn how to manipulate objects they never seen before, feel walls and forces in virtual reality, and so forth.

We explore how to add haptics to walls and other heavy objects in virtual reality. When a user tries to push such an object, our system actuates the user's shoulder, arm, and wrist muscles by means of electrical muscle stimulation, creating a counter force that pulls the user's arm backwards. Our device accomplishes this in a wearable form factor....

We explore how to create interactive systems based on electrical muscle stimulation that offer expressive output. We present muscle-plotter, a system that provides users with input and output access to a computer system while on the go. Using pen-on-paper interaction, muscle-plotter allows users to engage in cognitively demanding activities, such a...

Recently, researchers started to engineer not only the outer shape of objects, but also their internal microstructure. Such objects, typically based on 3D cell grids, are also known as metamaterials. Metamaterials have been used, for example, to create materials with soft and hard regions. So far, metamaterials were understood as materials-we want...

In my research, I investigate how users might interact with devices smaller than mobile or wearable devices. I argue that to achieve the intended minimal form-factor such devices will leverage the user's body as an input and output device. Users will not interact with the device but instead will interact through one of their limbs, which they share...

In this course, participants create their own prototypes using electrical muscle stimulation. We provide a ready-to-use device and toolkit that allows for programmatically actuating the user's muscles.

Leveraging the user's own muscles to simulate impact and forces from a virtual reality world allows us to create more immersive experiences without bulky equipment.

Motion platforms are used to increase the realism of virtual interaction. Unfortunately, their size and weight is proportional to the size of what they actuate. We present haptic turk, a different approach to motion platforms that is light and mobile. The key idea is to replace motors and mechanical components with humans. All haptic turk setups co...

Large-scale touch surfaces have been widely studied in literature and adopted for public installations such as interactive billboards. However, current designs do not take into consideration that touching the interactive surface at different heights is not the same; for body-height displays, the bottom portion of the screen is within easier reach o...

Motion platforms are used to increase the realism of virtual interaction. Unfortunately, their size and weight is proportional to what they actuate. We present haptic turk, a different approach to motion platforms that is light and mobile. The key idea is to replace motors and mechanical components with humans. All haptic turk setups consist of a p...

constructable is an interactive drafting table based on a laser cutter that produces precise physical output in every editing step. Users interact by drafting directly on the workpiece using a hand-held laser pointer. The system tracks the pointer, beautifies its path, and implements its effect by cutting the workpiece using a fast high-powered las...

We propose using spatial gestures not only for input but also for output. Analogous to gesture input, the proposed gesture output moves the user's finger in a gesture, which the user then recognizes. We use our concept in a mobile scenario where a motion path forming a "5" informs users about new emails, or a heart-shaped path serves as a mes- sage...

Force feedback devices resist miniaturization, because they require physical motors and mechanics. We propose mobile force feedback by eliminating motors and instead actuating the user's muscles using electrical stimulation. Without the motors, we obtain substantially smaller and more energy-efficient devices. We present a prototype that fits on th...

constructable is an interactive drafting table based on a laser cutter that produces precise physical output in every editing step. Users interact by drafting directly on the workpiece using a hand-held laser pointer. The system tracks the pointer, beautifies its path, and implements its effect by cutting the workpiece using a fast high-powered las...

We propose mobile force feedback devices based on actuating the user's muscles using electrical stimulation. Since this allows us to eliminate exoskeletons, motors and reduce battery size, our approach results in devices that are substantially smaller and lighter than traditional motor-based devices, and thus suitable for usage on-the-go. We presen...

Multitouch enabled surfaces can bring advantages to modelling scenarios, in particular if bimanual and pen input can be combined. In this work, we assess the suitability of multitouch interfaces to 3D sketching tasks. We developed a multitouch enabled version of ShapeShop, whereby bimanual gestures allow users to explore the canvas through camera o...

Personal fabrication tools, such as laser cutters and 3D printers allow users to create precise objects quickly. However, working through a CAD system removes users from the workpiece. Recent interactive fabrication tools reintroduce this directness, but at the expense of precision. In this paper, we introduce constructable, an interactive drafting...

We describe our experience in designing a system that would render a human operators job obsolete. In the course of a three year research project, we devised a 3D interactive system for the automotive design industry. Currently, automotive designers demonstrate prototype designs with the help of a showroom operator. With the addition of a new input...

Recognizing how a person actually touches a surface has generated a strong interest within the interactive surfaces community. Although we agree that touch is the main source of information, unless other cues are accounted for, user intention might not be accurately recognized. We propose to expand the expressiveness of touch interfaces by augmenti...

Presently, multi-touch interactive surfaces have widespread adoption as entertainment devices. Taking advantage of such devices, we present an interactive LEGO application, developed accordingly to an adaptation of building block metaphors and direct multi-touch manipulation. Our solution (LTouchIt) allows users to create 3D models on a tabletop su...

Multitouch enabled surfaces can bring advantages to modelling scenarios, in particular if bimanual and pen input can be combined. In this work, we assess the suitability of multitouch interfaces to 3D sketching tasks. We developed a multitouch enabled version of ShapeShop, whereby bimanual gestures allow users to explore the canvas through camera o...

The DJ culture uses a gesture lexicon strongly rooted in the traditional setup of turntables and a mixer. As novel tools are introduced in the DJ community, this lexicon is adapted to the features they provide. In particular, multitouch technologies can offer a new syntax while still supporting the old lexicon, which is desired by DJs. We present a...

We present an implementation of the Dynamic Time Warping algo-rithm for the Pure Data programming environment. This algorithm is fairly popular in several contexts, ranging from speech process-ing to pattern detection, mainly because it allows to compare and recognize data sets that may vary non-linearly in time. Our contri-bution is easily portabl...

Disc-jockeys have come a long way but, as far as DJing tools are concerned, there are still few applications that support hands-on interaction over Virtual DJ systems, and those are typically reduced to traditional input devices. With direct user-feedback from an accompanying group of DJ experts accounted for, we propose a Virtual DJ system with na...

Click Tracker is a tool designed for composers, conduc-tors and instrumentalists working with modern music. It allows users to prepare an accompanying click track of any musical score, independently of its complexity. Also, several of its multimodal features take advantage of both visual and aural feedback; making it suitable for musical study or l...