Research Area
Year Published

87 Results

October 22, 2017

Deltille Grids for Geometric Camera Calibration

International Conference on Computer Vision (ICCV)

The recent proliferation of high resolution cameras presents an opportunity to achieve unprecedented levels of precision in visual 3D reconstruction. Yet the camera calibration pipeline, developed decades ago using checkerboards, has remained the de facto standard. In this paper, we ask the question: are checkerboards the optimal pattern for high precision calibration?

By: Hyowon Ha, Michal Perdoch, Hatem Alismail, In So Kweon, Yaser Sheikh

September 24, 2017

Propagation of Joint Space Quantization Error to Operational Space Coordinates and Their Derivatives

IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)

In this paper, we characterize encoder error in a robotic system. Given encoder specifications, robot kinematics, and discrete transfer functions mapping coordinates to their derivatives, we describe the propagation of quantization error on joint space coordinates to operational space coordinates, joint space coordinate derivatives, and operational space coordinate derivatives.

By: Nick Colonnese, Allison M. Okamura
Areas: AR/VR

July 30, 2017

Focal Surface Displays

SIGGRAPH 2017

We introduce focal surface displays to meet the challenge of vergence-accommodation conflict, augmenting conventional HMDs with a phase-only spatial light modulator (SLM) placed between the display screen and viewing optics. This SLM acts as a dynamic freeform lens, shaping synthesized focal surfaces to conform to the virtual scene geometry.

By: Nathan Matsuda, Alexander Fix, Douglas Lanman
Areas: AR/VR

July 30, 2017

Low-Cost 360 Stereo Photography and Video Capture

SIGGRAPH 2017

In this work, we describe a method that takes images from two 360◦ spherical cameras and synthesizes an omni-directional stereo panorama with stereo in all directions. Our proposed method has a lower equipment cost than camera-ring alternatives, can be assembled with currently available off-the-shelf equipment, and is relatively small and light-weight compared to the alternatives.

By: Kevin Matzen, Michael Cohen, Bryce Evans, Johannes Kopf, Richard Szeliski

July 24, 2017

Development and Validation of Modeling Framework for Interconnected Tendon Networks in Robotic and Human Fingers

International Conference on Robotics and Automation (ICRA)

The primary contribution of this work is the development of a generalized modeling methodology for complex tendon systems toward a long-term goal of modeling the mechanical structure of the human finger.

By: Taylor D. Niehues, Raymond J. King, Ashish D. Deshpande, Sean Keller
Areas: AR/VR

June 6, 2017

Analysis of Effective Impedance Transmitted to the Operator in Position-Exchange Bilateral Teleoperation

IEEE World Haptics 2017

In this paper, we analyze the impedance transmitted to the operator in bilateral teleoperation including the effects of master and slave dynamics, local and communication time delay, low-pass filtering of the velocity estimate, and controller stiffness and damping, for three different environment dynamics: free, clamped, and a mass-damper-spring.

By: Nick Colonnese, Allison M. Okamura
Areas: AR/VR

May 30, 2017

Sensors for Future VR Applications

International Image Sensor Workshop (IISW)

In this paper, we provide examples of some tracking and mapping functions of virtual reality sensors that illustrate the critical requirements and performance metrics. The sensor performance, form factor, power, and data bandwidth are the main challenges in a battery powered, always on VR devices.

By: Chiao Liu, Michael Hall, Renzo De Nardi, Nicholas Trail, Richard Newcombe