37 research outputs found
HoloBeam: Paper-Thin Near-Eye Displays
An emerging alternative to conventional Augmented Reality (AR) glasses
designs, Beaming displays promise slim AR glasses free from challenging design
trade-offs, including battery-related limits or computational budget-related
issues. These beaming displays remove active components such as batteries and
electronics from AR glasses and move them to a projector that projects images
to a user from a distance (1-2 meters), where users wear only passive optical
eyepieces. However, earlier implementations of these displays delivered poor
resolutions (7 cycles per degree) without any optical focus cues and were
introduced with a bulky form-factor eyepiece (50 mm thick). This paper
introduces a new milestone for beaming displays, which we call HoloBeam. In
this new design, a custom holographic projector populates a micro-volume
located at some distance (1-2 meters) with multiple planes of images. Users
view magnified copies of these images from this small volume with the help of
an eyepiece that is either a Holographic Optical Element (HOE) or a set of
lenses. Our HoloBeam prototypes demonstrate the thinnest AR glasses to date
with a submillimeter thickness (e.g., HOE film is only 120 um thick). In
addition, HoloBeam prototypes demonstrate near retinal resolutions (24 cycles
per degree) with a 70 degrees-wide field of view.Comment: 15 pages, 18 Figures, 1 Table, 1 Listin
Flexible modeling of next-generation displays using a differentiable toolkit
We introduce an open-source toolkit for simulating optics and visual perception. The toolkit offers differentiable functions that ease the optimization process in design. In addition, this toolkit supports applications spanning from calculating holograms for holographic displays to foveation in computer graphics. We believe this toolkit offers a gateway to remove overheads in scientific research related to next-generation displays
HoloHDR: Multi-color Holograms Improve Dynamic Range
Holographic displays generate Three-Dimensional (3D) images by displaying
single-color holograms time-sequentially, each lit by a single-color light
source. However, representing each color one by one limits peak brightness and
dynamic range in holographic displays. This paper introduces a new driving
scheme, HoloHDR, for realizing higher dynamic range images in holographic
displays. Unlike the conventional driving scheme, in HoloHDR, three light
sources illuminate each displayed hologram simultaneously at various brightness
levels. In this way, HoloHDR reconstructs a multiplanar three-dimensional
target scene using consecutive multi-color holograms and persistence of vision.
We co-optimize multi-color holograms and required brightness levels from each
light source using a gradient descent-based optimizer with a combination of
application-specific loss terms. We experimentally demonstrate that HoloHDR can
increase the brightness levels in holographic displays up to three times with
support for a broader dynamic range, unlocking new potentials for perceptual
realism in holographic displays.Comment: 10 pages, 11 figure
Dynamic model and control of a new quadrotor unmanned aerial vehicle with tilt-wing mechanism
In this work a dynamic model of a new quadrotor aerial
vehicle that is equipped with a tilt-wing mechanism is presented.
The vehicle has the capabilities of vertical take-off/landing (VTOL)
like a helicopter and flying horizontal like an airplane. Dynamic
model of the vehicle is derived both for vertical and horizontal flight
modes using Newton-Euler formulation. An LQR controller for the
vertical flight mode has also been developed and its performance
has been tested with several simulations
Modeling and position control of a new quad-rotor unmanned aerial vehicle with tilt-wing mechanism
In this work a dynamic model of a new quadrotor aerial vehicle that is equipped with a tilt-wing mechanism is presented. The vehicle has the capabilities of vertical take-off/landing (VTOL) like a helicopter and flying horizontal like an airplane. Dynamic model of the vehicle is derived both for vertical and horizontal flight modes using Newton-Euler formulation. An LQR controller for the vertical flight mode has also been developed and its performance has been tested with several simulations
Mathematical modeling and vertical flight control of a tilt-wing UAV
This paper presents a mathematical model and vertical flight control algorithms for a new tilt-wing unmanned aerial vehicle (UAV). The vehicle is capable of vertical take-off and landing (VTOL). Due to its tilt-wing structure, it can also fly horizontally. The mathematical model of the vehicle is obtained using
Newton-Euler formulation. A gravity compensated PID controller is designed for altitude control, and three PID controllers are designed for attitude stabilization of the vehicle. Performances of these controllers are
found to be quite satisfactory as demonstrated by indoor and outdoor flight experiments
Optical Gaze Tracking with Spatially-Sparse Single-Pixel Detectors
Gaze tracking is an essential component of next generation displays for
virtual reality and augmented reality applications. Traditional camera-based
gaze trackers used in next generation displays are known to be lacking in one
or multiple of the following metrics: power consumption, cost, computational
complexity, estimation accuracy, latency, and form-factor. We propose the use
of discrete photodiodes and light-emitting diodes (LEDs) as an alternative to
traditional camera-based gaze tracking approaches while taking all of these
metrics into consideration. We begin by developing a rendering-based simulation
framework for understanding the relationship between light sources and a
virtual model eyeball. Findings from this framework are used for the placement
of LEDs and photodiodes. Our first prototype uses a neural network to obtain an
average error rate of 2.67{\deg} at 400Hz while demanding only 16mW. By
simplifying the implementation to using only LEDs, duplexed as light
transceivers, and more minimal machine learning model, namely a light-weight
supervised Gaussian process regression algorithm, we show that our second
prototype is capable of an average error rate of 1.57{\deg} at 250 Hz using 800
mW.Comment: 10 pages, 8 figures, published in IEEE International Symposium on
Mixed and Augmented Reality (ISMAR) 202