Cornell University Satellite
Encyclopedia
The Cornell University Satellite (CUSat) project is a multi-year effort to design, build, and launch an end-to-end autonomous on orbit inspection system. The CUSat system will demonstrate a process through which one satellite can diagnose the structural health and configuration of another; a capability that will benefit commercial, government, and manned space missions envisioned for the coming decades. The space segment consists of two functionally identical satellites that will launch together and separate on orbit in a target-inspector configuration. Once in orbit, CUSat will use microthrust Pulsed Plasma Thruster
s (PPTs) and sub-centimeter level accurate Carrier-phase Differential GPS (CDGPS) to navigate the satellites to within ten meters of each other. The inspector satellite will use cameras to gather imagery of the target satellite while performing relative navigation. Target satellite imagery will be transferred to the ground segment where they will be used to reconstruct a three dimensional model for the end user.
CUSat was the winner of the University Nanosat-4 Program
which aims to educate the future aerospace workforce and develop new space technologies. As part of this program, CUSat completed environmental testing and other aspects of final I&T in the AFRL Aerospace Engineering Facility at Kirtland Air Force Base
. CUSat is working with AFRL to complete the Department of Defense SERB process in preparation for a launch with the Space Test Program
.
s will adjust the attitude for a proper separation.
While still in illumination, CUsat is then able to perform a low-shock separation through the use of a lightband into Top and Bottom satellites. After separation, CUSat enters Phase Four: Inspection
On the ground, the downlinked data will then be used to construct a 3D image of CUSat to verify the CDGPS data.
for the CUSat project is Dr. Mason Peck. The two advisors for the CUSat project are Dr. Mark Campbell and Dr. Mark Psiaki.
, it is composed of a multitude of different students with a variety of abilities and talents. Team members come from such majors as Electrical and Computer Engineering, Mechanical and Aerospace Engineering, Applied and Engineering Physics, Computer Science
, Economics and Management, and even Architecture
.
CUSat recruits Cornell students with a good technical background and a strong commitment for work, regardless of their level.
(PPTs) and reaction wheels. The software portion of ADCNS will consist of the relative navigation algorithms, which will run the various modes of operation defined by the CONOPs.
format, and relaying them to the onboard computer, C&DH.
and C++, C&DH will execute the ADCNS algorithms and flight code.
panels as well as numerous electronics board enclosures.
s (PPTs) which give each satellite three degrees of translational freedom and three degrees of rotational freedom.
extensively. The Systems group is largely responsible for providing the project with direction by creating top level system requirements, creating best practices, maintaining communications, making design choices, and creating processes for creating a successful product. Each of the subsystem leads also participates as a member of the Systems group, which allows the project to maintain consistency and focus.
Pulsed plasma thruster
Pulsed plasma thrusters are a method of spacecraft propulsion also known as Plasma Jet Engines in general. They use an arc of electric current adjacent to a solid propellant, to produce a quick and repeatable burst of impulse...
s (PPTs) and sub-centimeter level accurate Carrier-phase Differential GPS (CDGPS) to navigate the satellites to within ten meters of each other. The inspector satellite will use cameras to gather imagery of the target satellite while performing relative navigation. Target satellite imagery will be transferred to the ground segment where they will be used to reconstruct a three dimensional model for the end user.
CUSat was the winner of the University Nanosat-4 Program
University Nanosatellite Program
The University Nanosat Program, a satellite design and fabrication competition for universities jointly administered by the Air Force Office of Scientific Research , the Air Force Research Laboratory , the American Institute of Aeronautics and Astronautics , and the Space Development and Test Wing,...
which aims to educate the future aerospace workforce and develop new space technologies. As part of this program, CUSat completed environmental testing and other aspects of final I&T in the AFRL Aerospace Engineering Facility at Kirtland Air Force Base
Kirtland Air Force Base
Kirtland Air Force Base is a United States Air Force base located in the southeast quadrant of the Albuquerque, New Mexico urban area, adjacent to the Albuquerque International Sunport. The base was named for the early Army aviator Col. Roy C. Kirtland...
. CUSat is working with AFRL to complete the Department of Defense SERB process in preparation for a launch with the Space Test Program
Space Test Program
The Space Test Program is the primary provider of spaceflight for the United States Department of Defense space science and technology community. STP is conducted by the Space Development and Test Wing of the United States Air Force...
.
Phase One: Launch
CUSat will launch as a secondary payload on a launch vehicle. Once in orbit and in the correct attitude, CUSat will separate from the launch vehicle where it will begin Phase Two - the initialization.Phase Two: Initialization
Once CUSat separates from the launch vehicle and enters the Initialization Phase, it will enter solar illumination where the spacecraft will power on. The spacecraft will make contact with the Mission Control Center at Cornell through one of several ground stations, beaconing its status. Next, the spacecraft will begin to assess its tumble rates, and will detumble if required. Once stabilized, CUSat will begin commissioning operations. Operators in the MCC will assess the health of most satellite subsystems. Durin this time, the top spacecraft will begin to search for surrounding GPS satellites. A Carrier-phase Differential GPS Lock is then acquired to obtain an accurate attitude solution. The spacecraft will enter Phase Three: Spacecraft Separation.Phase Three: Spacecraft Separation
Once an attitude solution is obtained, CUSat's actuatorActuator
An actuator is a type of motor for moving or controlling a mechanism or system. It is operated by a source of energy, usually in the form of an electric current, hydraulic fluid pressure or pneumatic pressure, and converts that energy into some kind of motion. An actuator is the mechanism by which...
s will adjust the attitude for a proper separation.
While still in illumination, CUsat is then able to perform a low-shock separation through the use of a lightband into Top and Bottom satellites. After separation, CUSat enters Phase Four: Inspection
Phase Four: Inspection
Once both Top and Bottom satellites obtain a GPS lock, the relative distance between the two will be calculated via CDGPS. When the partner satellite enters an operational camera's field of view, the inspecting satellite will acquire images of the partner satellite. The ground will request specific images, which will be subsequently downlinked from the space segment in the next communication opportunity.On the ground, the downlinked data will then be used to construct a 3D image of CUSat to verify the CDGPS data.
Administration
The Principal InvestigatorPrincipal investigator
A principal investigator is the lead scientist or engineer for a particular well-defined science project, such as a laboratory study or clinical trial....
for the CUSat project is Dr. Mason Peck. The two advisors for the CUSat project are Dr. Mark Campbell and Dr. Mark Psiaki.
Technical Backgrounds
Because CUSat is an Engineering Project Team at Cornell UniversityCornell University
Cornell University is an Ivy League university located in Ithaca, New York, United States. It is a private land-grant university, receiving annual funding from the State of New York for certain educational missions...
, it is composed of a multitude of different students with a variety of abilities and talents. Team members come from such majors as Electrical and Computer Engineering, Mechanical and Aerospace Engineering, Applied and Engineering Physics, Computer Science
Computer science
Computer science or computing science is the study of the theoretical foundations of information and computation and of practical techniques for their implementation and application in computer systems...
, Economics and Management, and even Architecture
Architecture
Architecture is both the process and product of planning, designing and construction. Architectural works, in the material form of buildings, are often perceived as cultural and political symbols and as works of art...
.
CUSat recruits Cornell students with a good technical background and a strong commitment for work, regardless of their level.
Subsystems
There has been a major redistribution of work, into different subsystems since FCR. The current Subsystems are listed below.ADCNS
The Attitude Determination, Control, and Navigation Subsystem (ADCNS) executes the relative navigation that will be used for CUSat's in-orbit inspection procedures. CUSat will primarily be using three GPS boards for attitude determination. For attitude control, CUSat will be using pulsed-plasma thrustersPulsed plasma thruster
Pulsed plasma thrusters are a method of spacecraft propulsion also known as Plasma Jet Engines in general. They use an arc of electric current adjacent to a solid propellant, to produce a quick and repeatable burst of impulse...
(PPTs) and reaction wheels. The software portion of ADCNS will consist of the relative navigation algorithms, which will run the various modes of operation defined by the CONOPs.
Camera
The camera team is responsible for acquiring images while in orbit, compressing them in a modified JPEGJPEG
In computing, JPEG . The degree of compression can be adjusted, allowing a selectable tradeoff between storage size and image quality. JPEG typically achieves 10:1 compression with little perceptible loss in image quality....
format, and relaying them to the onboard computer, C&DH.
Command and Data Handling
C&DH is the central hub for communication and computation on the satellite. Using a commercial off the shelf (COTS) single board computer running Windows CEWindows CE
Microsoft Windows CE is an operating system developed by Microsoft for embedded systems. Windows CE is a distinct operating system and kernel, rather than a trimmed-down version of desktop Windows...
and C++, C&DH will execute the ADCNS algorithms and flight code.
GPS
The GPS team is responsible for the GPS receivers, antennas and algorithms used to calculate sub-centimeter relative positioning.Ground Segment
The Ground Segment is responsible for the ground operations of the satellite, including ground to satellite communication, tracking and commanding.Harness
The Harness subsystem is responsible for satellite wiring, the electronics backplane, the electrical interface boards, and any System level electrical concerns.Industry Relations
The Industry Relations team is responsible for marketing CUSat and seeking commercial and academic sponsorship.Integration and Testing
The I&T team is responsible for enabling rapid integration and testing of CUSat. I&T is also responsible for testing CUSat in Cornell University's thermal vacuum chamber.Mechanical Hardware
The Mechanical Hardware team manufactures the satellite structure and manages the design. The structure includes eight isogridIsogrid
An isogrid is a plate with triangular integral stiffening ribs . The stiffeners of an isogrid are generally machined from a single sheet of material with a milling machine, though below 0.004 in. thickness chemical milling processes must be used...
panels as well as numerous electronics board enclosures.
Mission Ops
The Mission Ops team defines the detailed, on orbit operations plan for both CUSat satellites. Operating procedures are defined to match with hardware and mission specifications and help ensure successful execution of the mission.Power
The power team is responsible for harnessing solar energy, storing it, and distributing it throughout the satellite.Propulsion
The propulsion team is responsible for CUSat's pulsed plasma thrusterPulsed plasma thruster
Pulsed plasma thrusters are a method of spacecraft propulsion also known as Plasma Jet Engines in general. They use an arc of electric current adjacent to a solid propellant, to produce a quick and repeatable burst of impulse...
s (PPTs) which give each satellite three degrees of translational freedom and three degrees of rotational freedom.
Structures
The structures team is responsible for designing, analyzing, and manufacturing the body of the satellite as well as the logistics of the internal components.Survivability
The Survivability team is responsible for analyzing and controlling the satellite's thermal, electrical and vibrational environment on the ground, during launch, and in orbit. Analyzed effects include ESD, atomic oxygen effects, venting and outgassing.Systems
The CUSat Satellite project employs Systems EngineeringSystems engineering
Systems engineering is an interdisciplinary field of engineering that focuses on how complex engineering projects should be designed and managed over the life cycle of the project. Issues such as logistics, the coordination of different teams, and automatic control of machinery become more...
extensively. The Systems group is largely responsible for providing the project with direction by creating top level system requirements, creating best practices, maintaining communications, making design choices, and creating processes for creating a successful product. Each of the subsystem leads also participates as a member of the Systems group, which allows the project to maintain consistency and focus.