Laboratory for Advanced Space Systems at Illinois (LASSI)

Michael F. Lembeck, Ph.D., a Professor of Practice in the Aerospace Engineering Department, is Director of the Laboratory for Advanced Space Systems at Illinois (LASSI). Dr. Lembeck has led or worked on multiple government and commercial spaceflight programs, including JPL’s Galileo Jupiter Orbiter, Space Industries, Inc.’s Wake Shield Facility, Orbital Sciences’ OrbView/Warfighter commercial remote sensing program, NASA’s Vision for Space Exploration, and the Boeing commercial crew program.

Our first satellite, CubeSail, was launched in December, 2018 on a Rocket Lab Electron rocket from New Zealand. CubeSail’s mission culminates in the deployment demonstration of a 260 m long solar reflecting film ribbon in mid-2020. Four other satellites are in various stages of development as depicted in the graphic below.

Facility and Equipment Description

	CubeSail	LAICE	CapSat	SpaceICE	SASSI^2
CubeSat Class	2 X 1.5 U	6U	3U	3U	3U
Science Mission Objection	Ultra-sail 260 m-long, 20m2 solar reflecting film ribbon deployment experiment	Atmostpheric gravity wave studies	Active cooling for CubeSats, quantum annealing, and fine pointing control via solar panel deformation	Freeze-casting experiments to measure solidification velocity, dendrite and wall width, and particle concentration	Spectrometer studies of chemical reactions and chemical species present during re-entry
Mass	3.5 kg	6.5 kg	2.8 kg	3.4 kg	3.3 kg
Orbit Average Power	13.2 W	24 W	17.3 W	15.6 W	15.6 W
Collaborators	JPL CU Aerospace	VA Polytechnic	JPL ARC NSF	Northwestern	Purdue
Sponsor	NASA ELaNa	NSF	NASA USIP	NASA ELaNA	NASA USIP
Launch Date	4Q2018	TBD	4Q2019	2Q2020	2Q2019

Facility and Equipment Description

The laboratory is equipped with a Clean Room, Thermal-Vacuum Chamber, Vacuum Oven, Sun Simulator, Earth Orbital Magnetic Simulator, and a range of mechanical and electrical diagnostic equipment. Multiple forms of rapid prototyping, design, and simulation capabilities are also provided.

Clean Room

LASSI’s clean room provides a pristine environment for spaceflight hardware assembly and test. Filtered air maintains a positive pressure in the room to keep “dirty” air away from the systems being worked on grounded work benches inside the protected environment.

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Thermal Vacuum Chamber

The thermal vacuum chamber enables spacecraft and space systems to be tested in a simulated space environment. It is capable of achieving vacuum levels as low as 1e-10 Torr, and a temperature range of +100C. The thermal vacuum chamber is equipped with a residual gas analyzer to assist with determination of outgassing.

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Vacuum Oven

The vacuum oven is connected to a roughing pump, and can achieve temperatures as hot as 250C and pressures as low as 400 mTorr. The vacuum oven is used primarily for spacecraft bake-out, but can also be used for adhesive preparation and vacuum curing.

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Moment of Inertia Measurement Device

Developed by our students, the Moment of Inertia Measurement Device is capable of determining the inertia about the orthogonal body axes of a satellite or piece of hardware. It optically tracks targets on a plate with a known inertia to calculate the effective balance changes caused by the object being measured.

Center of Gravity Calculation Device

This device calculates the two-dimensional center of gravity of an object placed upon it. It is used typically to find the center of gravity of satellites and their subsystems. By taking three measurements, one for each orthogonal pair of directions, the full 3D location of the center of gravity can be determined.

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Sun Simulator

The sun simulator can produce both AM0 and AM1.5 solar spectrum with a 98% accuracy across all wavelengths. Sun intensity is adjustable from about 0.8 to 1.2 AU. Its primary use is to test and calibrate solar panels, but it can be used to test individual solar cells and entire power systems. This equipment is critical in the testing chain for most spacecraft, to ensure that they will generate power in space.

Helmholz Cage

The “HC3” 3-axis Helmholtz cage is capable of reproducing the magnetic field encountered in low earth orbit. It has six magnetic coils attached to a custom, student-designed power supply. This equipment is used for calibration of magnetometers, testing of magnetic torque coils, and all-up attitude determination and control testing. It can be fitted with an air bearing for additional fidelity of motion.

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Rapid Prototyping

The lab also provides two forms of rapid prototyping capability: the X-Carve automated CNC machine and a pair of Form 2 SLA printers. These allow students in the lab to construct satellite parts and fixtures for testing.

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CubeSat Research Highlights

CubeSail

CubeSail is a pair of 1.5U CubeSats that launch attached to each other. Once in orbit, they separate and deploy a 250 m long solar sail demonstrating the technology, in preparation for future I-Sail and UltraSail missions. CubeSail launched in December of 2018.

Check out more on CubeSail here.

Lower Atmosphere/Ionosphere Coupling Experiment (LAICE)

LAICE is a 6U CubeSat developed by the University of  Illinois and Virginia Tech, funded by NSF. This mission seeks to develop correlations between atmospheric air glow events with in-situ sensed chemical changes, using a combination of photomultipliers, a retarding potential analyzer, and neutral and ion density measurements. LAICE is expected to launch in 2020.

Check out more on LAICE here.

Student Aerothermal Spectrometer Satellite of Illinois and Indiana (SASSI²)

SASSI² is a small satellite mission scheduled to be flown in spring 2019. This mission is being developed at the University of Illinois at Urbana-Champaign in partnership with Purdue University as a part of the Undergraduate Student Instrument Program (USIP). The goal of the mission is to characterize the flow field and radiation generated by the diffuse bow shock formed during high-speed flight through the upper atmosphere. Optical spectrographic measurements of the radiation will be taken to provide data for fundamental flow, radiation, and materials modelling, resulting in improved prediction of the aerothermodynamic environment encountered by bodies during atmospheric entry.

Check out more on SASSI² here.

Space Interface Convective Effects (SpaceICE)

The SpaceICE mission aims to investigate the influence of gravity during directional solidification for the purpose of improving terrestrially-based materials fabricated using the freeze-casting technique. The Northwestern University-provided scientific payload consists of two aqueous particle suspension samples and one aqueous solution sample which will be repeatedly solidified (and melted) over the course of the mission. Scientific instrumentation includes cameras for imaging the solidification process and thermocouples for taking in-situ temperature measurements during solidification.

Small spacecraft (especially CubeSats) are faced with significant thermal challenges as they get bigger. Historically, spacecraft less than 20 kg used passive cooling, however this is no longer keeping up as smaller, higher powered technology can fit in less volume and consume less mass. Multiple currently planned missions for small satellites to the moon are reporting to face overheat conditions and need to power cycling their commu- nication systems, computers, and thrusters. The Spacecraft Active Cooling Thermal Sys- tem is an attempt to address this need; by circulating a fluid through a microvascular radiator panel, the system can supply on-demand cooling. As such, the spacecraft can dumb tens of Watts of heat when needed, but can stop dumping heat when running cold, and therefore avoid freezing by retaining internal heat.

Check out more on SpaceICE here.