In the middle of this year, a rocket will take off from the Baikonur launch site in Kazakhstan. The mission, AlSat Nano, will carry three experimental payloads, developed by UK academic-industrial partnerships, intended to demonstrate the potential for the ‘CubeSat’ concept, whereby satellite hardware is packaged in geometrical ‘envelopes’ that are multiples of 10cm cubes.
The goal of the project is to move to a new phase in the commercial and scientific exploitation of Earth orbit through developing satellites that are small, light, and much cheaper in terms of both the hardware itself and its launch requirements.
This prospect could present an opportunity for a new breed of companies – small, innovative, flexible and entrepreneurial – to develop appropriate technologies. One such firm is Oxford Space Systems (OSS). It was set up in 2013 and received its first funding four months later, but it is already leading one of the payload initiatives. The particular project involved, SpaceMag-PVBoom, will use one of the company’s technologies – an ultra lightweight boom system provided by a thin roll of carbon fibre material paid out from an initial tightly compressed form. But the crucial factor involved is as much time as space. No-one previously has developed a new technology and put it into orbit in a timescale of less than three years – instead, as much as three times that has been the norm, says Mike Lawton, founder and chief executive of OSS.
Move from monoliths
The size of the company, and the way it operates, also represent a marked contrast with the business model of the space industry that was until recently the norm – that of monolithic, publicly funded agencies placing contracts with large, well-established contractors. OSS employs just 13 people full-time, says Lawton.
As such, the company’s location at the Harwell Space Cluster site, just south of Oxford, is crucial. A key factor is the availability of test facilities provided by the RAL Space operation of the Rutherford Appleton Laboratory, that provides OSS with a set of sophisticated capabilities for proving out its designs right on its doorstep, and which it can hire on an as-needed basis, he says. The company also aims to work with ‘strategic partners’ to keep itself as lean as possible.
Another factor that facilitates the starting up of companies such as OSS is the increasing attractiveness of the sector to the venture capital industry. In this respect, the general environment has changed markedly over the past two to three years, says Lawton. It is evident in the case of OSS, which has raised two substantial tranches of cash – respectively £600,000 and £1.3 million – with relative ease, he says. Indeed, in the second instance it was oversubscribed by 30%.
Lowering the stakes
At the moment, the financial and technical aspects of the industry are mutually reinforcing, he says. The new technologies that are appearing are lowering the overall costs of getting payloads into orbit, and hence lowering the stakes for those taking the risks. “It used to be said that this was an industry in which you couldn’t afford to fail, but now you can. You can carry out your final stages of research and development in ‘low Earth orbit’.” The commercial exploration of space is entering “a new
era”, he says.
Moreover, both technological and commercial trends increasingly militate in favour of small, new companies in the space industry. What Lawton describes as “old space” businesses are simply “not set up to develop disruptive technologies because they cannot predict a financial return”. So genuine innovation is left to the growing number of small businesses working on space projects. “We de-risk new technologies, and then they fall within the comfort zone of old space,” he says.
The actual cost of getting a payload into Earth orbit remains the same – about £20,000 per kilogram, says Lawton – so reducing overall cost means reducing weight. To that end, OSS is developing three broad product families. These are:
• Its AstroTube range of linear boom systems, which comprise both the carbon fibre strip technology that will go into orbit this year and a ‘max’ version in which the material is used to fashion a sequence of telescopic tubes;
• Deployable panels most obviously to carry solar arrays, which in OSS’s case are supported by a hinge technology to enable multiple panel sections to be unfolded in succession;
• Large, unfurlable antennae.
In the immediate term, the area of opportunity for companies such as OSS is in low Earth orbit – at altitudes of 200-500km above the Earth’s surface, says Lawton. The type of application involved might, for instance, be Earth observation. With modern, high-definition cameras, a CubeSat satellite – likely to comprise at least three cubes – could return sub-metre-resolution images to the ground. This observation might facilitate, for instance, monitoring of crops or of ships at sea, though there is no requirement for monitoring systems to be confined to the visual light spectrum.
Short lifespan
Around 350 CubeSat format satellites are already in orbit, most of them representing academic research projects. The costs involved mean that getting into space is no longer the preserve of governments. Indeed, they are now coming within the reach even of ‘high-net-worth individuals’, says Lawton. The project also represents a market with a high in-built demand, he adds. The smaller CubeSat satellites are simply not big enough to carry onboard propulsion systems to enable them to stay in prolonged orbit, so they are likely to fall back to Earth after a lifespan of just two to three years.
In general, the effectiveness of CubeSats is impeded by factors that are a direct consequence of their dimensions. These include limited power generation because of the restricted size of the solar arrays they can deploy, and similar restraints on the bandwidth of the data they can transmit because of the smaller antennae they carry, says Lawton. Another limit is the distance that booms can be extended from the main body of the satellite. The greater the distance, the more effectively instruments on the end of the booms can be insulated from electro-magnetic interference from the satellite’s own systems. All these concerns are targets for OSS’s technology development.
In-house innovation
But venture capital support of the sort on which OSS depends is not available for ‘me too’ technologies, says Lawton. So the company is developing its own proprietary technologies to provide it with innovative capacity. In particular, it has developed what he describes as a carbon fibre-based flexible composite material that forms the basis of its AstroTube system – the technology due to go into orbit this year.
He shows off a working model in which around two metres of the material emerges smoothly and continuously from an initial volume equivalent to a cigarette packet. In contrast, he says, the conventional approach would involve an articulated arm that would be limited to a maximum distance of one satellite length – just 30cm for the three-cube format that represents the current minimum effective size for a CubeSat satellite. The OSS system provides advantages for the performance of ultra-sensitive devices such as magnetometers that might be deployed at the end of the boom. Moreover, the system can also just as easily work in reverse to allow devices to be reset if necessary.
But OSS has not patented the material, says Lawton. “There would be no better way to tell your competitors about it,” he says. Instead, the formula that provides it with its innovative properties is shared among a handful of key staff, who are incentivised to stay with the company.
In line with the company’s policy of establishing strategic partnerships, the material is made under the terms of a confidentiality agreement by an external composites shop. But to satisfy OSS’s demands, the partner in question is not a specialist space industry supplier but part of the Formula One racing business, he says. “It can turn things around in 48 hours. So that enables us to have a fast, iterative development cycle.”
The company’s use of its own carbon fibre material formulation does not stop there. A variant – “different lay-up, slightly different resin system” – also forms the basis of its AstroHinge system, to enable the deployment of a succession of large panels out from a satellite body. In this case, the material acts like a spring, to separate the panels from each other and lock them into position, obviating any need for electric motors. It also forms the basis of an unfurlable antenna system – this time with the aid of a coating material that the company is developing – though this initiative is still in its early stages.
For the antenna system, OSS is seeking to construct a specialist test rig, likely to cost between £50,000 and £80,000, that will simulate a zero gravity environment, says Lawton. There are limits to the extent that space conditions can be replicated by unfurling a model across the floor on castors, he says.
But whatever the application, the challenges of creating systems that will work in space remain the same – working in a vacuum, and a temperature range that may vary from -150°C to +120°C. Those conditions produce effects that make tasks that might be straightforward on Earth complex and challenging. For instance, bare metal surfaces in contact with each other will weld themselves together, while conventional lubricants will simply evaporate, he says.
Within those parameters, the unchanging objective will be to develop technologies that can reduce the weight of the payloads that the company’s customers want to put into space. “Gravity is not going away,” says Lawton.
IMechE support: Stephenson fund
The IMechE’s Stephenson Fund was set up last year to support innovative start-ups working in mechanical engineering and to achieve one of the George Stephenson’s original aims in 1847 for the institution to “give an impulse to invention likely to be useful to the world”
Oxford Space Systems was one of the first companies to be awarded a share
of the £2 million fund last September to develop its lightweight, structures for space.