Evacuated Enclosure Mounted Acoustic Actuator and Passive Attenuator

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77190/1/AIAA-2002-1355-680.pd

Building Satellites in 18 Months: Lessons Learned from the Rogue Alpha/Beta CubeSats

The Department of the Air Force initiated the Rogue Alpha/Beta Cube Satellite program to challenge The Aerospace Corporation to investigate rapid reconstitution capabilities. The primary objective was to demonstrate swift development of a low cost, small size, weight, and power infrared sensing satellite in Low Earth Orbit via schedule adherence to launch in 18 months. Aerospace achieved this goal by building two identical 3U satellites made with commercial and non-exotic components. The team was dedicated to building, testing, and making sure the spacecraft met all milestones successfully, providing pertinent lessons. First, complications faced during assembly helped lay standards for future use of commercial parts in proliferated networks. Second, the team learned the importance of conducting rigorous inspections to reduce trouble shooting later. Third was the value of developing a commoditized bus to allow for deeper pay load focus, especially for satellite constellations. Finally, the team identified the impending need for small, affordable, and swiftly obtainable CNSSP-12 encryption solutions for future Department of Defense missions utilizing small satellites. With the vehicles in space, the team expects to gain valuable information on the infrared sensors used, create a baseline for LEO infrared imaging algorithm development, and evaluate LEO concept of operations for multiple satellites

Cabin fuselage structural design with engine installation and control system

Design requirements for the cabin, cabin system, flight controls, engine installation, and wing-fuselage interface that provide adequate interior volume for occupant seating, cabin ingress and egress, and safety are presented. The fuselage structure must be sufficient to meet the loadings specified in the appropriate sections of Federal Aviation Regulation Part 23. The critical structure must provide a safe life of 10(exp 6) load cycles and 10,000 operational mission cycles. The cabin seating and controls must provide adjustment to account for various pilot physiques and to aid in maintenance and operation of the aircraft. Seats and doors shall not bind or lockup under normal operation. Cabin systems such as heating and ventilation, electrical, lighting, intercom, and avionics must be included in the design. The control system will consist of ailerons, elevator, and rudders. The system must provide required deflections with a combination of push rods, bell cranks, pulleys, and linkages. The system will be free from slack and provide smooth operation without binding. Environmental considerations include variations in temperature and atmospheric pressure, protection against sand, dust, rain, humidity, ice, snow, salt/fog atmosphere, wind and gusts, and shock and vibration. The following design goals were set to meet the requirements of the statement of work: safety, performance, manufacturing and cost. To prevent the engine from penetrating the passenger area in the event of a crash was the primary safety concern. Weight and the fuselage aerodynamics were the primary performance concerns. Commonality and ease of manufacturing were major considerations to reduce cost

Flight Operations of Two Rapidly Assembled CubeSats with Commercial Infrared Cameras: The Rogue-Alpha,Beta Program

The Aerospace Corporation’s Rogue-alpha, betaprogram, co-funded by the Space and Missile Systems Center’s Development Corps, is a rapid prototyping effort that built and launched two 3-Unit CubeSats equipped with modified commercial IR camera payloads, laser communications and precision pointing capabilities in 18-months. Launched on 2 November 2019, the two spacecraft were released from the ISS Cygnus NG-12 robotic resupply spacecraft on 31 January 2020 into a circular 460-km, 52° inclined orbit. The two Rogue spacecraft are serving as testbeds for studying wide-field-of-view fast-framing imaging, on-orbit stellar calibration techniques for small IR payloads, and associated spacecraft flight operations. Precision pointing is enabled by three star sensors. High data rate sensor observations are enabled by the ultra-compact 200 Mbps lasercom system, which downlinks gigabytes of stored data during a single laser contact, using The Aerospace Corporation’s prototype ground stations located in El Segundo, California. The Rogue-alpha, beta IR sensor is a 1.4 micron band, 640x512 pixel, 28° field of view, InGaAs SWIR camera. It is accompanied by a panchromatic, 10-megapixel, 37° field of view visible context camera. Modes of sensor operation have included: 1) horizon-pointed imaging in all directions relative to the spacecraft orbit (fore, aft, port, and starboard) which is designed to maximize the imaged field of view, 2) point-and-stare imaging, 3) nadir-pointed, and 4) stereo fore-aft pointing using both spacecraft. All of these modes of operation are usually conducted in multi-frame collections at 1-20hz for dozens to thousands of frames. Highlights from the Rogue-alpha, beta sensor Earth remote sensing observation experiments will be presented. These have included impressive video imagery of hurricanes, typhoons, thunderstorms, and high clouds in the intra-tropical convergence zone. Infrared and visible point sources studied include gas flares, wildfires, active volcanos, nighttime lights, and other phenomena, including the first infrared CubeSat observations of space launch upper stages in flight. Stereo cloud imaging observations were also conducted with an aim of better understanding Earth backgrounds from low Earth orbit. Highlights from the CubeSat flight operations experiments include: 1) spacecraft-to-spacecraft boresight alignment of Rogue’s lasercom systems, and 2) metric and radiometric calibration of Rogue’s flight cameras using bright infrared stars. The results from the Rogue-alpha, beta460-km orbit show the exciting possibilities for wide-field-of-view missions from low earth orbit