Gradient-like observer design on the Special Euclidean group SE(3) with system outputs on the real projective space

A nonlinear observer on the Special Euclidean group $\mathrm{SE(3)}$ for full pose estimation, that takes the system outputs on the real projective space directly as inputs, is proposed. The observer derivation is based on a recent advanced theory on nonlinear observer design. A key advantage with respect to existing pose observers on $\mathrm{SE(3)}$ is that we can now incorporate in a unique observer different types of measurements such as vectorial measurements of known inertial vectors and position measurements of known feature points. The proposed observer is extended allowing for the compensation of unknown constant bias present in the velocity measurements. Rigorous stability analyses are equally provided. Excellent performance of the proposed observers are shown by means of simulations

An Equivariant Observer Design for Visual Localisation and Mapping

This paper builds on recent work on Simultaneous Localisation and Mapping (SLAM) in the non-linear observer community, by framing the visual localisation and mapping problem as a continuous-time equivariant observer design problem on the symmetry group of a kinematic system. The state-space is a quotient of the robot pose expressed on SE(3) and multiple copies of real projective space, used to represent both points in space and bearings in a single unified framework. An observer with decoupled Riccati-gains for each landmark is derived and we show that its error system is almost globally asymptotically stable and exponentially stable in-the-large.Comment: 12 pages, 2 figures, published in 2019 IEEE CD

Observer design for position and velocity bias estimation from a single direction output

This paper addresses the problem of estimating the position of an object moving in $R^n$ from direction and velocity measurements. After addressing observability issues associated with this problem, a nonlinear observer is designed so as to encompass the case where the measured velocity is corrupted by a constant bias. Global exponential convergence of the estimation error is proved under a condition of persistent excitation upon the direction measurements. Simulation results illustrate the performance of the observer.Comment: 6 pages, 6 figure

The Resource Conservation and Recovery Act and Mineral Development

30 pages

The Resource Conservation and Recovery Act and Mineral Development

30 pages

African American Men Survey

A comprehensive survey looking at how African-American men view their lives in the United States and their outlook for the future. The survey gauges the views and experiences of African-American men on marriage and family, education, careers and health, among other issues, and includes comparisons to the views and experiences of African-American women and white men and women. The African-American Men Survey is the 15th survey in a series generated under a three-way partnership between The Washington Post, the Kaiser Family Foundation and Harvard University. The three organizations work together to pick the survey topics, design the survey instruments and analyze the results. The survey's findings were published in the June 4, 2006, edition of The Washington Post. This survey was conducted by telephone from March 20 to April 29, 2006, among 2,864 randomly selected adults nationwide, including: 1,328 black men; 507 black women; 437 white men and 495 white women. Results for total respondents have been weighted so that black respondents are represented in proportion to their actual share of the population. Margin of sampling error is plus or minus 3 percentage points for results based on all respondents or black men, 5 percentage points for black women and 6 percentage points for white men or women. Hispanics and Asians were interviewed along with white and black respondents, but because of the relative size of those populations, there were not enough respondents to break out separately. The complete survey results and detailed methodology description are available in the toplines document

On the structure of kinematic systems with complete symmetry

This paper provides a new perspective on the structure of kinematic systems with complete symmetry. These systems naturally occur as models for mechanical systems with symmetry, for example flying or submersible robots. The configuration space of such systems is a homogeneous space of the symmetry Lie group, and it is well known that their kinematics can be lifted to equivariant kinematics on the symmetry group thus allowing global state observer constructions. We provide explicitly checkable sufficient differential-algebraic conditions on the symmetry that will lead to a lifted system in the form of standard left or right invariant kinematics on the symmetry group. Previously known conditions for one of these two cases required finding a velocity lift map with particular properties for which there was no general construction known.This work was partially supported by the Australian Research Council through the ARC Discovery Project DP160100783 “Sensing a complex world: Infinite dimensional observer theory for robots”