SSTL’s Optical Payload Group is currently building two Dynamic Multi Star-field Simulators (DMSS) at its Sevenoaks facility that will be used to test star trackers that will be flown in space under simulated operating conditions here on Earth.

Star trackers are an essential subsystem in any satellite, providing information that allows the spacecraft's on board computer to determine its orientation or “pointing” at any point in time.

They work by taking an image of a region of the sky using a specially designed optical camera, and comparing successive images to determine how much the orientation of the satellite has drifted.

This information is then sent to an attitude control system that corrects for the drift by using on-board thrusters or other motion-generating devices to maintain the correct satellite pointing.

Any time a satellite is manoeuvred in orbit, the pointing information from star trackers is vital to the spacecraft’s control systems. For example, solar panels must be aligned to capture the maximum available light from the Sun, and communications antennae pointed towards the Earth.

Star trackers are now available that operate in autonomous modes. These units are able to dynamically monitor the star fields in orbit and provide correction information back to the satellite to counteract adverse platform manoeuvres, such as slews and spins, which is particularly useful in the early stage of mission operations or following a major system failure.

To test these units on the ground prior to launch, it is essential to present the star trackers with a dynamically varying star field. This is where the DMSS comes in.

Continue reading "Simulators prepare star trackers for spaceflight"

SSTL and its US operation SST US are attending the Satellite 2010 exhibition at National Harbor, Maryland, USA from 16-18 March 2010.

Visit Surrey Satellite Technology Ltd on stand 1925.

SST US CEO John Paffett will be joined by Kathryn O'Donnell, Yasrine Ibnyahya and Simon Crouch from SSTL and Brent Abbott, Becky Yoder and Katherine Defoe from SST US.

Come and find out about how we deliver low risk high performance satellites at a fraction of the price usually associated with such levels of capability.

Sir Martin Sweeting :

So President Obama has scrapped the US plans for a manned return to the Moon. As the world claws it way out of recession, many might see this decision as being financially prudent. However, the exploration of the lunar surface is still very much on the agenda. But it won’t be man making one small step next time, it will be a robot!

Several nations are planning robotic lunar missions including India, China, Korea and interestingly, the USA. And when you think about it, this makes perfect sense because robotic lunar missions are much more cost effective than manned missions, although not so emotive. Of course, robotic exploration is nothing new with NASA and ESA both utilising this technology, but it’s still very expensive. The price tag for the European ExoMars programme is around €1Bn which is a lot of money in any currency. But does robotic exploration have to be this expensive?

At SSTL we don’t think so. We think it is possible to knock a “0” off the cost of mounting lunar robotic exploration mission by simply employing the same, well founded, production techniques that SSTL use to reduce the cost of designing and building Earth-orbiting small satellites.

Currently, there is enormous interest in the moon, particularly with the prospect of finding water, the key perhaps to a permanent manned lunar base in the future. The LRO and LCROSS missions are currently surveying the lunar surface to identify future landing sites. Now is the time to mount a low cost robotic mission to Moon in order to prove the technology and its suitability for other more distant planetary missions.

As part of its mini-series looking at the state of British manufacturing, BBC Breakfast's Tim Muffett visited SSTL's headquarters in Guildford to find the secrets of its success.

The video report gives a sneak peak at cleanroom operations and mission control. Mr Muffet also catches up briefly with SSTL CEO Matt Perkins and Business Development Manager Phil Davies to discuss how SSTL hs carved a unique niche in the international space market with its low cost alternatives to conventional space missions.

If you missed BBC Breakfast this morning, or if like many Space Blog visitors you are from abroad you can watch the video report Surrey satellite firm weathers the recession online.