18 research outputs found
Learning Privacy Preserving Encodings through Adversarial Training
We present a framework to learn privacy-preserving encodings of images that
inhibit inference of chosen private attributes, while allowing recovery of
other desirable information. Rather than simply inhibiting a given fixed
pre-trained estimator, our goal is that an estimator be unable to learn to
accurately predict the private attributes even with knowledge of the encoding
function. We use a natural adversarial optimization-based formulation for
this---training the encoding function against a classifier for the private
attribute, with both modeled as deep neural networks. The key contribution of
our work is a stable and convergent optimization approach that is successful at
learning an encoder with our desired properties---maintaining utility while
inhibiting inference of private attributes, not just within the adversarial
optimization, but also by classifiers that are trained after the encoder is
fixed. We adopt a rigorous experimental protocol for verification wherein
classifiers are trained exhaustively till saturation on the fixed encoders. We
evaluate our approach on tasks of real-world complexity---learning
high-dimensional encodings that inhibit detection of different scene
categories---and find that it yields encoders that are resilient at maintaining
privacy.Comment: To appear in WACV 201
Design of an Adaptive Lightweight LiDAR to Decouple Robot-Camera Geometry
A fundamental challenge in robot perception is the coupling of the sensor
pose and robot pose. This has led to research in active vision where robot pose
is changed to reorient the sensor to areas of interest for perception. Further,
egomotion such as jitter, and external effects such as wind and others affect
perception requiring additional effort in software such as image stabilization.
This effect is particularly pronounced in micro-air vehicles and micro-robots
who typically are lighter and subject to larger jitter but do not have the
computational capability to perform stabilization in real-time. We present a
novel microelectromechanical (MEMS) mirror LiDAR system to change the field of
view of the LiDAR independent of the robot motion. Our design has the potential
for use on small, low-power systems where the expensive components of the LiDAR
can be placed external to the small robot. We show the utility of our approach
in simulation and on prototype hardware mounted on a UAV. We believe that this
LiDAR and its compact movable scanning design provide mechanisms to decouple
robot and sensor geometry allowing us to simplify robot perception. We also
demonstrate examples of motion compensation using IMU and external odometry
feedback in hardware.Comment: This paper is published in IEEE Transactions on Robotic
Data-Fusion for a Vision-Aided Radiological Detection System: Sensor dependence and Source Tracking
The University of Florida is taking a multidisciplinary approach to fuse the data between 3D vision sensors and radiological sensors in hopes of creating a system capable of not only detecting the presence of a radiological threat, but also tracking it. The key to developing such a vision-aided radiological detection system, lies in the count rate being inversely dependent on the square of the distance. Presented in this paper are the results of the calibration algorithm used to predict the location of the radiological detectors based on 3D distance from the source to the detector (vision data) and the detectors count rate (radiological data). Also presented are the results of two correlation methods used to explore source tracking