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SpaceX's reusable rocket program aims to reduce the cost of space travel by making rockets that can land, refuel and refly, instead of being thrown away after every flight. Autonomous precision landing of a rocket is a unique problem, which has been likened to balancing a rubber broomstick on your hand in a windstorm. Rockets do not have wings (unlike airplanes) and they cannot rely on a high ballistic coefficient to fly in a straight line (unlike missiles). In the past two years, SpaceX has successfully landed nineteen rockets, some of which were on dry land at Cape Canaveral, and some of which were on floating platforms in the ocean. This talk will discuss the challenges involved, how these challenges were overcome, and next steps towards rapid reusability.
Lars Blackmore is responsible for Entry, Descent and Landing of SpaceX's Falcon 9 Reusable (F9R) rocket. His team developed the precision landing algorithms and operations required to bring F9R back to the launch site. Previously, Lars was with the NASA Jet Propulsion Laboratory, where he was co... read more »
Dramatic progress has been made in the last decade and a half towards realizing solid-state systems for quantum information processing with superconducting quantum circuits. Artificial atoms (or qubits) based on Josephson junctions have improved their coherence times more than a million-fold, have been entangled, and used to perform simple quantum algorithms. The next challenge for the field is demonstrating quantum error correction that actually improves the lifetimes, a necessary step for building more complex systems.
Here we demonstrate a fully operational quantum error correction system, based on a logical encoding comprised of superpositions of cat states in a superconducting cavity. This system uses real-time classical feedback to encode, track the naturally occurring errors, decode, and correct, all without the need for post-selection. Using this approach we reach, for the first time, the break-even point for QEC and preserve quantum information through active means.
Moreover, the performance of the system matches with predictions, and can be dramatically improved by making the protocol more fault tolerant. Mastering the practice of error correction, and understanding the overhead and complexity required, are the main scientific challenges remaining for reaching scalable quantum computation with this technology.
Robert Schoelkopf is the Sterling Professor of Applied Physics and Physics at Yale University. His research focuses on the development of superconducting devices for quantum information processing, which will lead to revolutionary advances in computing.
Over 300 years ago, an English carpenter realized that the key to safely navigating the ocean was being able to precisely measure time. Since then, timing and localization technologies have continued to push the limits of technology resulting in systems like GPS and our most sophisticated scientific instruments. Our new challenge in localization is providing coverage for indoor spaces where barriers attenuate and scatter radio signals. Precise indoor localization has the potential to enable applications ranging from asset tracking, indoor navigation and augmented reality all the way to highly optimized beam forming for improved spatial capacity of wireless networks.
In this talk, I will describe a localization system that uses time synchronized beacons with a combination of Bluetooth Low-Energy (BLE) and ultrasonic signals that are able to provide decimeter-ranging accuracy. The ultrasonic transmissions are designed to be inaudible to humans, but still detectable by microphones found on standard mobile devices. We are able to further improve localization performance by fusing information from the phone’s IMU as well as constraints derived from building floor plans. As these systems scale, we show how pedestrian range-based Simultaneous Localization and Mapping (SLAM) can be used to bootstrap the beaconing infrastructure as well as detect and correct configuration faults.
Anthony Rowe is an Associate Professor in the Electrical and Computer Engineering Department at Carnegie Mellon University. His research interests are in networked real-time embedded systems with a focus on wireless communication. His most recent projects have related to large-scale... read more »