Evolution of the Phoenix EDL System Architecture

This viewgraph presentation gives a general overview of the Phoenix spacecraft evolution, entry, descent, landing and system architecture

Overview of the Phoenix Entry, Descent and Landing System Architecture

NASA s Phoenix Mars Lander began its journey to Mars from Cape Canaveral, Florida in August 2007, but its journey to the launch pad began many years earlier in 1997 as NASA s Mars Surveyor Program 2001 Lander. In the intervening years, the entry, descent and landing (EDL) system architecture went through a series of changes, resulting in the system flown to the surface of Mars on May 25th, 2008. Some changes, such as entry velocity and landing site elevation, were the result of differences in mission design. Other changes, including the removal of hypersonic guidance, the reformulation of the parachute deployment algorithm, and the addition of the backshell avoidance maneuver, were driven by constant efforts to augment system robustness. An overview of the Phoenix EDL system architecture is presented along with rationales driving these architectural changes

A Message from the Desert

We were shot in the middle of the desert by a hippie chick in a van. Actually it was a photo-shoot for Architecture Magazine last year. We were one of nine architecture design firms chosen by the magazine and told to meet in the parking lot of a Quick Mart in Apache Junction, Arizona, about thirty miles east of Phoenix

A new way to see inside black holes

Black holes are real astrophysical objects, but their interiors are hidden and can only be "observed" through mathematics. The structure of rotating black holes is typically illustrated with the help of special coordinates. But any such coordinate choice necessarily results in a distorted view, just as the choice of projection distorts a map of the Earth. The truest way to depict the properties of a black hole is through quantities that are coordinate-invariant. We compute and plot all the independent curvature invariants of rotating, charged black holes for the first time, revealing a landscape that is much more beautiful and complex than usually thought.Comment: 4 pages, 3 figures, published in Bridges Baltimore 2015: Mathematics, Music, Art, Architecture, Culture (Phoenix, AZ: Tessellations Publishing, 2015), 479-482. Revised to fix a referenc

National Register Nomination: the French House, 1287 Hope Street Bristol, Rhode Island 02809

This document serves as a National Register Nomination for the French House located at 1287 Hope Street in Bristol, Rhode Island. The French House is nominated under Criterion B for its association with Col. George T. French Esq., and Criterion C for its contribution to the Stick style of architecture in Bristol, Rhode Island. Built in 1881, the French House is a Vernacular Stick style cottage and gains its local significance under Criterion B for its relationship and association with Col. George T. French Esq., French was a lawyer, politician, patriot, and former Brown University student who dedicated his life to being a local influence on the Town of Bristol and the State of Rhode Island. French contributed to the development of the State of Rhode Island through his professional career of being a member on the Rhode Island Bar (1875-1885), a member of the House of Representatives, and a member of the Rhode Island General Assembly (1883-1885). French’s life was dedicated to the people of Bristol and the State of Rhode Island while serving on the General Assembly under Governor Augustus O. Bourne (1883-1885). French’s involvement in the policymaking and planning of the Bourne Amendment, which was added to Rhode Island’s Constitution, declared the removal of the real estate requirement for voting in state elections imposed in 1843 against naturalized citizens. This allowed citizens that did not own property to have the right to vote. This significant amendment highlighted French’s professional career as a politician because it altered the lives of countless naturalized citizens who previously were not entitled the right to vote in any state elections. This set the precedent for the future of democracy in the United States of America. In addition to being a politician and lawyer, French was a respected representative of the community. Bristol, Rhode Island is famed for having the oldest 4th of July Celebration in the United States of America. Since 1776, Bristol has been celebrating the Declaration of Independence, and for the 200th Bristol 4th of July Celebration in 1880 Samuel P. Colt acted as the chair of the planning committee. Since 1785, Patriot Speakers or the Speaker of the Day is chosen to speak to the entire community to launch the community celebration of the 4th of July. This position is reserved for respected and influential figures in the community. In 1882, the chosen 97th Patriotic Speaker was none other than Col. George T. French. This honor was indicative of French’s popularity and familiarity in the Bristol community. More recent Patriotic Speakers include nationally recognizable political figures such as Claiborne Pell, the namesake for the Claiborne Pell Bridge (Newport Bridge), and Ira C. Magazine, President William Clinton’s Senior Advisor Policymaker. The French House is nominated under Criterion C for its significance as a representation of Late Victorian Architecture in Bristol. Built in 1881, by local builder William Hall of Warren, Rhode Island, the French House is a Victorian cottage built in the Stick style as illustrated by its asymmetrical form, multiple paned window sash, spacious verandah decorated with simple diagonal brackets, steeply pitched gable roofs with intersecting cross gables, king posts and struts, and corbeled chimneys. The French House although does not have any applied high-style stick-work, yet characterizes an interpretation of ornamentation through its overall architectural elements, and massing. The Stick style, even at a vernacular level, is not prevalent in Bristol, making the French House one of the few, if not the only Stick style residential architecture in the town. The French House has retained most of its historic integrity and despite its neglected state, the house represents a style of architecture that scarcity deems it worthy of recognition and preservation

The Phoenix Drone: An Open-Source Dual-Rotor Tail-Sitter Platform for Research and Education

In this paper, we introduce the Phoenix drone: the first completely open-source tail-sitter micro aerial vehicle (MAV) platform. The vehicle has a highly versatile, dual-rotor design and is engineered to be low-cost and easily extensible/modifiable. Our open-source release includes all of the design documents, software resources, and simulation tools needed to build and fly a high-performance tail-sitter for research and educational purposes. The drone has been developed for precision flight with a high degree of control authority. Our design methodology included extensive testing and characterization of the aerodynamic properties of the vehicle. The platform incorporates many off-the-shelf components and 3D-printed parts, in order to keep the cost down. Nonetheless, the paper includes results from flight trials which demonstrate that the vehicle is capable of very stable hovering and accurate trajectory tracking. Our hope is that the open-source Phoenix reference design will be useful to both researchers and educators. In particular, the details in this paper and the available open-source materials should enable learners to gain an understanding of aerodynamics, flight control, state estimation, software design, and simulation, while experimenting with a unique aerial robot.Comment: In Proceedings of the IEEE International Conference on Robotics and Automation (ICRA'19), Montreal, Canada, May 20-24, 201