Bright sparks redefine propulsion

CubeSats, like STRaND-1, are essential for the breakthrough of new technologies in the space industry. The relatively inexpensive CubeSat enables institutes and companies to test technologies and gain valuable flight heritage without risking millions (or even billions) of pounds of investment.

STRaND-1, the joint project between SSTL and the Surrey Space Centre (SSC), is one of these exciting experimental satellites and it’s not only its smartphone that makes it exceptional. Engineers at the Surrey Space Centre have also developed a unique mass and power saving plasma propulsion system to fly on the satellite. This system will be the first propulsive technology to provide very precise attitude control and pointing.

Pulsed Plasma Thruster flight hardware
Pulsed Plasma Thruster flight hardware

STRaND-1 will carry both a Resistojet and a Pulsed Plasma Thruster (PPT) module on board. The PPT will consist of eight micro thrusters; four located at the top of the satellite stack and four located at the bottom. The micro thrusters operate by discharging a discrete train of pulses. Each pulse is a plasma discharge that forms between two metal electrodes, much like a small lightning bolt or electrical spark. The spark erodes the metal from the electrodes and electromagnetics accelerate the eroded mass out of the nozzle, which produces thrust. This is known as the Lorentz force.

Surrey Space Centre has developed two ways of minimising mass and volume. Firstly, the electrodes which form the plasma discharge also function as the propellant. As metal is highly dense, more propellant can be stored in a smaller volume than that of conventional chemical propulsion systems. The total weight of the propellant for the whole STRaND-1 PPT system is just 10g.

Secondly, Surrey Space Centre’s novel discharge initiation system uses a mechanical contact trigger built out of a tiny piezoelectric motor only 5mm in length. This takes up less space than the conventional spark plug system which requires volume intensive circuitry.

The Pulsed Plasma Thruster module firing
The Pulsed Plasma Thruster module firing

Not only does SSC’s PPT module reduce mass and volume, it also uses less power than other propulsion systems. Between each pulse, energy is stored in a capacitor. This substantially reduces the power requirements for the thruster, making it perfect for small satellites such as STRaND-1. In fact, the power requirement for the system flying on STRaND-1 is only 1.5W, about the power needed to operate a bicycle light.

If successful, the STRaND-1 PPT will be the first propulsion system to provide full axis control on this class of satellite. Having an active propulsion system in orbit would open up new possibilities for future CubeSat missions like rendezvous and docking, and flyby inspection. The flight heritage and experience gained in using the PPT on STRaND-1 could then be transferred and scaled for other SSTL missions providing a low cost, mass and volume solution for future endeavours.

For updates on STRaND-1, visit the Facebook page or follow @SurreyNanosats on Twitter!

Read about STRaND-1 in a free sample issue of OSCAR News at http://www.uk.amsat.org/on_193_final.pdf

Vega Satellite Deployments

Artists impression of Vega launch

Artists impression of Vega launch

Vega is presently scheduled to launch at 0900 UT on Thursday, Feb 9, with eight student built amateur radio satellites.

The launcher will first deploy the main payload,  the LARES the Laser relativity Spacecraft and will then make an additional firing of the final Attitude & Vernier Upper Module (AVUM) stage before deploying the secondary payloads. the planned timing for these deployments are as follows:

T0+ 4245.30secs first PPOD, with (in order of ejection) XatCobeo, e-st@r, and Goliat
T0+ 4255.30secs second PPOD, with (in order of ejection) Robusta, MaSat-1 and  PW-Sat
T0+ 4265.30secs third PPOD, with UniCubeSat only
These Cubesats will not deploy their antennas until >1800 seconds after they leave their PODS
T0+ 4275.30secs  AlmaSat-1 – it is not known how soon this spacecraft will start transmitting after deployment

Pre-launch TLEs have not yet been made available but all the teams will certainly appreciate reception reports on the day. All observers are being encouraged to join the CubeSat IRC chat channel to pass on their news and comments in realtime. Using the irc.freenode.net server please join the #cubesat channel. It is recommended that you change you nickname to “name_callsign”.

For frequencies of the eight student amateur radio satellites to be deployed by Vega see http://www.uk.amsat.org/4180

Vega Elliptical Orbit Video http://www.uk.amsat.org/4119

How Disposable, Networked Satellites Will Democratize Space

A New Standard	 Satoshi

A New Standard Satoshi

In 1999, professors Robert Twiggs of Stanford University and Jordi Puig-Suari of California Polytechnic State University began to standardize the satellite business. They designed a small orbital unit-–a four-inch cube with little metal feet–-that was wide enough for solar cells, basing their design on a plastic display box for Beanie Babies. Their “CubeSat” had enough room for a computer motherboard and a few other parts necessary to do limited experiments in space, such as monitoring weather or photographing Earth. The design would significantly lower the cost for students to conduct experiments in space. CubeSats could be launched at the same time and piggyback on larger, more expensive missions, mitigating the expense of getting satellites into orbit.

With the design complete, Puig-Suari began to work with the three U.S. agencies that regularly launch satellites—the National Reconnaissance Office, the Department of Defense’s Space Test Program and NASA—to convince them to build CubeSat-ready berths into as many launches as possible. Meanwhile, the aerospace engineering department at CalPoly has become a sort of standards clearinghouse for NASA, testing each academic satellite to make sure the box won’t shake itself apart and cast shrapnel through the rocket during launch. CalPoly and Stanford maintain a forum and post all standards on CubeSat.org.

With so many scheduled launches, an undergraduate engineering student […] can design one during her freshman year and see it reach space before graduation.Twiggs and Puig-Suari’s efforts are paying off. Since 2001, about 50 CubeSats have entered space. The pair sent up their first in 2003, spending $100,000 in grant money to stow it on a Russian Dnepr launch. When the SpaceX Falcon 9 rocket launched in December 2009, six CubSats were aboard, packed three units at a time inside a spring-loaded jack-in-the-box container called a Poly-Picosatellite Orbital Deployer (P-POD), that was developed at CalPoly. After the payload deployed, the door of the P-POD popped open and the spring pushed all three satellites into orbit, where they unfurled solar panels and began transmitting information to their creators below. This year at least three rockets will launch with room for CubeSats, including the NROL-36, which can fit 11.

With so many scheduled launches, an undergraduate engineering student at one of the nearly 100 schools making CubeSats can design one during her freshman year and see it reach space before graduation. When Roland Coelho, a CalPoly graduate student, was filling out a preflight survey for his CubeSat last year, the range safety officer at Vandenberg Air Force Base in California approached him in confusion. “It asks whether you’ll need a military convoy to escort you,” the officer said. “You don’t?”

“Oh, that’s right,” Coelho replied. “It fits in the trunk of my car.”

Many academic CubeSats currently in orbit report their position, battery life and findings to ham-radio operators on Earth, who forward the information to the originating school. But projects are becoming more ambitious. The Air Force plans to use two networked CubeSats to monitor the Earth’s atmosphere and provide the world’s first real-time look at space weather. Carl Brandon of Vermont Technical College is developing an ion-drive CubeSat system that he says will be able to propel itself to the moon.

Puig-Suari and Charles Scott MacGillivray, who ran a small team of satellite developers at Boeing until last year, have now spun off their own company, called Tyvak, which produces CubeSats on a contract basis for private clients and the U.S. government. A marketplace of standardized components has also emerged, led by Stanford engineering professor Andrew Kalman’s Pumpkin, Inc., which has sold CubeSat kits to more than 100 universities, governments and nonprofit organizations. Kalman says that once people begin to think of CubeSats as disposable, building them out of off-the-shelf components and sending them up 100 at a time, the devices will truly have come of age. “If we launch a group of satellites built out of Android phones, you’ll have app developers able to dream up what to put in space,” he says.

A CubeSat today can cost as little as $100,000 to build, and buying a berth on something like a Falcon 9 runs around $250,000. In the aerospace industry, that’s spare change. The low cost also makes losing a CubeSat tolerable. Last March, a rocket carrying NASA’s Glory satellite and three CubeSats crashed into the ocean. “We were bummed,” says Coelho, who watched the failed launch. “But the NASA guys had lost a $400 million satellite.” One of the lost CubeSats was, in fact, a duplicate. In October, its twin made it into space.

CubeSat:  Austin Williams/Polysat, California Polytechnic University

HOW TO READY A CUBESAT FOR SPACE

The pre-launch guidelines for CubeSats stipulate that the object must be 10 by 10 by 11 centimeters (the extra centimeter is for the little metal feet) and no heavier than 1.3 kilograms. A satellite must remain fully deactivated—no power of any kind—until it exits its spring-loaded launch container; errant signals could scramble the electronics of the primary payload or the rocket’s guidance system. And teams must submit a detailed plan for de-orbiting—tipping the satellite such that it disintegrates in the atmosphere—within five years of leaving Earth, or risk having their satellite killed before it ever takes off.

Schools' communications satellite to put the fun back into science lessons

FUNcube_Graphic_Large

Artists impression of FUNcube in space

The Jan 25-31 printed edition of Electronics Weekly (circulation 36,400) carries an article on the AMSAT-UK FUNcube amateur radio satellite. The article, titled “Schools’ communications satellite to put the fun back into science lessons”, appears on page 12.

You can read or download this issue of Electronics Weekly at http://cde.cerosmedia.com/1M4f1d2b906fdb1433.cde

(The PDF can be downloaded by clicking on the PDF icon at the top).

A free subscription to the digital version of the publication is available via the Electronics Weekly website http://www.electronicsweekly.com/ On the lef-hand side under “SIGN UP TO” click on “Digital Magazine”.

Schools’ communications satellite to put the fun back into science lessons

FUNcube_Graphic_Large

Artists impression of FUNcube in space

The Jan 25-31 printed edition of Electronics Weekly (circulation 36,400) carries an article on the AMSAT-UK FUNcube amateur radio satellite. The article, titled “Schools’ communications satellite to put the fun back into science lessons”, appears on page 12.

You can read or download this issue of Electronics Weekly at http://cde.cerosmedia.com/1M4f1d2b906fdb1433.cde

(The PDF can be downloaded by clicking on the PDF icon at the top).

A free subscription to the digital version of the publication is available via the Electronics Weekly website http://www.electronicsweekly.com/ On the lef-hand side under “SIGN UP TO” click on “Digital Magazine”.

RS-39 (Chibis-M) Deploys

RS-39 Chibis-M

RS-39 Chibis-M

RS-39 has CW beacons on 435.315 and 435.215 MHz that can be received directly by schools and colleges for educational outreach purposes. It deployed from Progress M-13M into a 500 km orbit on January 24 at approximately 23:18:30 UT.

On November 2, 2011 cargo ship “Progress M-13M”, which also delivered microsatellite “Chibis-M”, was docked with ISS. The main purpose of “Chibis-M” is the study of physical processes in the vicinity of the lightning, during which the Terrestrial Gamma Ray Flashes (TGFs) are generated. TGFs are likely produced by beams of very energetic electrons, which are accelerated in the intense electric fields generated by large thunderstorm systems.

The deployment of “Chibis-M” in a circular orbit of 500 km will take place during the final phase of “Progress M-13M” operation. According to the plan of the Russian Space Control Centre, undocking of “Progress M-13M” will occur at January 24, 01:59 msk and after two corrections it will be positioned at 500 km orbit. At January 25, 03:14 msk “Chibis-M” will separate. Beside scientific data “Chibis-M” will transmit service telemetry (the housekeeping parameters) in the beacon format on 435.315 or 435.215 MHz CW (Doppler shift +/- 10 kHz) and has the designation of RS-39. The format of data is typical for RS satellites and can be downloaded here.

The telemetry of RS-39 can be easily received directly by schools and colleges for educational outreach purposes. This telemetry will give details of the spacecraft’s health – battery voltages and temperatures of critical units. In combination with orbital data such information will be useful as the curriculum for student lessons.

The team of RS-39 will very much appreciate any reception reports of “Chibis-M”. Special attention is requested for the first orbits as these are outside of control stations for “Chibis-M”. Each report will be confirmed by special QSL card. The email address is amateur-rs39@chibis.cosmos.ru

The RS-39 Chibis-M website managed the by Space Research Institute of the Russian Academy of Sciences (RAS) can be seen in Russian at http://chibis.cosmos.ru/ or in Google English at http://tinyurl.com/RS-39-Chibis-M

As well as measuring electromagnetic parameters of “space weather” in the spectrum 0.1 – 40 kHz the satellite also carries a receiver for the analysis of radio frequency signals in a frequency band of 26-48 MHz. http://www.energia.ru/en/iss/researches/geophis/19.html

RS-39 Morse Code telemetry format http://tinyurl.com/RS-39-Morse-Code-Telemetry

RS-39 Telemetry Decoder http://www.uk.amsat.org/4029

RS-39 Real Time Tracking Map http://chibis.cosmos.ru/cyclogr/prepare1/google/index.html
For Keps click on two gear wheels in top left-hand corner then click on Satellites.

It may be worth checking the AMSAT Bulletin Board (AMSAT-BB) for the very latest news. The 48-hour archive of the AMSAT-BB is at http://www.amsat.org/amsat/archive/amsat-bb/48hour/threads.html or you can join the bulletin board at http://www.amsat.org/amsat-new/tools/maillist/maillist.php