Skin-integrated haptic interfaces that can relay a wealth of information from the machine to the human are of great interest. However, existing haptic devices are not yet able to produce haptic cues that are compatible with the skin. In this work, we present the stretchable soft actuators for haptic feedback, which can match the perception range, spatial resolution, and stretchability of the skin. Pressure-amplification structures are fabricated using a scalable self-assembly process to ensure an output pressure beyond the skin perception threshold. Due to the minimized device size, the actuator array can be fabricated with a sufficiently high spatial resolution, which makes the haptic device applicable for skin locations with the highest spatial acuity. A haptic feedback system is demonstrated by employing the developed soft actuators and highly sensitive pressure sensors. Two proof-of-concept applications are developed to illustrate the capability of transferring information related to surface textures and object shapes acquired at the robot side to the user side.
Development of an Innovative Magnetorheological Fluids-based Haptic Device Excited by Permanent Magnets *
A number of haptic displays based on smart fluidic materials such as electrorheological (ERFs) and magnetorheological fluids (MRFs) have been fabricated. These displays are relevant to medical virtual environments where it is important to create realistic simulations of soft tissues with varying stiffness. In this paper a new haptic device is described that was designed in consideration of the limitations of an earlier MRF display. The new prototype consists of 400 permanent magnets (PMs) arranged in a 20x20 array that is underneath a chamber filled with MRF. The magnetic field within the fluid is controlled by 400 PM stepping motors that move the magnets vertically. The magnetic behavior of the device was simulated using FEM which indicated that its spatial resolution was substantially improved when compared to the earlier prototype and that objects as small as 10 mm can be rendered. The device was fabricated and assembled and measurements demonstrated the accuracy of the FE model. Its novelty is demonstrated by the increased intensity of the magnetic field produced and the enhanced spatial resolution. These features will enable the dynamic presentation of haptic information such as object shape and compliance which will be characterized in future psychophysical experiments.
more »
« less
- Award ID(s):
- 2006152
- PAR ID:
- 10290100
- Date Published:
- Journal Name:
- IEEE World Haptics Conference
- Page Range / eLocation ID:
- 61 to 66
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
Abstract -
null (Ed.)Abstract The emergence of atomically thin van der Waals magnets provides a new platform for the studies of two-dimensional magnetism and its applications. However, the widely used measurement methods in recent studies cannot provide quantitative information of the magnetization nor achieve nanoscale spatial resolution. These capabilities are essential to explore the rich properties of magnetic domains and spin textures. Here, we employ cryogenic scanning magnetometry using a single-electron spin of a nitrogen-vacancy center in a diamond probe to unambiguously prove the existence of magnetic domains and study their dynamics in atomically thin CrBr 3 . By controlling the magnetic domain evolution as a function of magnetic field, we find that the pinning effect is a dominant coercivity mechanism and determine the magnetization of a CrBr 3 bilayer to be about 26 Bohr magnetons per square nanometer. The high spatial resolution of this technique enables imaging of magnetic domains and allows to locate the sites of defects that pin the domain walls and nucleate the reverse domains. Our work highlights scanning nitrogen-vacancy center magnetometry as a quantitative probe to explore nanoscale features in two-dimensional magnets.more » « less
-
Regular user interface screens can display dense and detailed information to human users but miss out on providing somatosensory stimuli that take full advantage of human spatial cognition. Therefore, the development of new haptic displays can strengthen human-machine communication by augmenting visual communication with tactile stimulation needed to transform information from digital to spatial/physical environments. Shape-changing interfaces, such as pin arrays and robotic surfaces, are one method for providing this spatial dimension of feedback; however, these displays are often either limited in maximum extension or require bulky mechanical components. In this paper, we present a compact pneumatically actuated soft growing pin for inflatable haptic interfaces. Each pin consists of a rigid, air-tight chamber, an inflatable fabric pin, and a passive spring-actuated reel mechanism. The device behavior was experimentally characterized, showing extension to 18.5 cm with relatively low pressure input (1.75 psi, 12.01 kPa), and the behavior was compared to the mathematical model of soft growing robots. The results showed that the extension of the soft pin can be accurately modeled and controlled using pressure as input. Finally, we demonstrate the feasibility of implementing individually actuated soft growing pins to create an inflatable haptic surface.more » « less
-
Handheld kinesthetic haptic interfaces can provide greater mobility and richer tactile information as compared to traditional grounded devices. In this paper, we introduce a new handheld haptic interface which takes input using bidirectional coupled finger flexion. We present the device design motivation and design details and experimentally evaluate its performance in terms of transparency and rendering bandwidth using a handheld prototype device. In addition, we assess the device's functional performance through a user study comparing the proposed device to a commonly used grounded input device in a set of targeting and tracking tasks.more » « less
-
We propose a haptic device that alters the perceived softness of real rigid objects without requiring to instrument the objects. Instead, our haptic device works by restricting the user's fingerpad lateral deformation via a hollow frame that squeezes the sides of the fingerpad. This causes the fingerpad to become bulgier than it originally was—when users touch an object's surface with their now-restricted fingerpad, they feel the object to be softer than it is. To illustrate the extent of softness illusion induced by our device, touching the tip of a wooden chopstick will feel as soft as a rubber eraser. Our haptic device operates by pulling the hollow frame using a motor. Unlike most wearable haptic devices, which cover up the user's fingerpad to create force sensations, our device creates softness while leaving the center of the fingerpad free, which allows the users to feel most of the object they are interacting with. This makes our device a unique contribution to altering the softness of everyday objects, creating “buttons” by softening protrusions of existing appliances or tangibles, or even, altering the softness of handheld props for VR. Finally, we validated our device through two studies: (1) a psychophysics study showed that the device brings down the perceived softness of any object between 50A-90A to around 40A (on Shore A hardness scale); and (2) a user study demonstrated that participants preferred our device for interactive applications that leverage haptic props, such as making a VR prop feel softer or making a rigid 3D printed remote control feel softer on its button.more » « less