October 25, 2017

DodecaPen: Accurate 6DoF Tracking of a Passive Stylus

ACM Symposium on User Interface Software and Technology (UIST)

We propose a system for real-time six degrees of freedom (6DoF) tracking of a passive stylus that achieves sub-millimeter accuracy, which is suitable for writing or drawing in mixed reality applications.

Po-Chen Wu, Robert Wang, Kenrick Kin, Christopher Twigg, Shangchen Han, Ming-Hsuan Yang, Shao-Yi Chien
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.

Nick Colonnese, Allison M. Okamura
July 31, 2017

Focal Surface Displays


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.

Nathan Matsuda, Alexander Fix, Douglas Lanman
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.

Nick Colonnese, Allison M. Okamura