PocketQube: CubeSat's Little Brother
In April 2013 I posted a DesignSpark blog post on the launch into Earth orbit of tiny, cheap Nanosat satellites built to a standard pattern called a CubeSat. Thanks to the miniaturisation of electronics the format is one of a 10cm cube. Femtosats are even smaller: one design, called a PocketQube, is basically a 5cm cube and eight would fit inside a CubeSat. Surely a step too far?
In November 2013 as part of its secondary payload, a Russian DNEPR rocket (an ex-ICBM) sent a Microsat called UniSat-5 into Earth orbit. This Microsat is roughly a 50cm cube and contained launchers for a number of 10cm CubeSats and 5cm PocketQubes. Two of the satellites successfully deployed are the UK Amateur Radio Education CubeSat FUNcube-1 and a PocketQube Wren. The latter has reaction wheels and plasma thrusters to control its position(!).
PocketQubes are considerably cheaper to make and launch than CubeSats, so they provide an opportunity for less well-endowed educational establishments to get involved in practical space science. Money aside, it’s still a pretty daunting prospect and from tomorrow (Fri 10th January) a web shop opens for business to provide support to budding space engineers. PocketQubeShop will sell hardware kits and guide you around the many pitfalls awaiting the inexperienced. For instance, although FUNcube-1 is a British satellite, the difficulties of obtaining space licensing under UK legislation means it is flying under a Dutch flag. Unbelievable.
Now PocketQubes may be tiny but as the Wren satellite demonstrates a great deal can be packed into a few cubic centimetres. Two pending product launches by companies at opposite ends of the wealth range look very interesting for ‘Pocket applications’: Intel Edison, a dual-core Pentium-class SBC in the format of an SD Flash card and Micro Python, an ARM Cortex-M4 based SBC programmed in a custom version of Python with a PCB footprint of about 33 x 40mm.
The Micro Python was a hugely oversubscribed Kickstarter project and includes a 3-axis accelerometer and MicroSD card slot. Its STM32 microcontroller uses the M4F variant of the ARM Cortex family which means it has a full set of DSP instructions and a hardware Floating Point Unit, making it a good choice for real-time embedded control applications. I backed this project myself and I'll post a review when the board arrives.
There have been negative reactions to what some people consider is surrounding the planet with space junk, but these satellites are generally placed in low orbits and won’t stay up for long. In fact, ‘self-destruct’ mechanisms are being developed to force the satellite out of orbit and burn up in the atmosphere.
If you fancy the rocketry side of space engineering then there are CanSats. A Sounding Rocket is used to launch a data collection payload into the upper atmosphere which then returns to earth by parachute. There's even an international competition. As an aside, the first Skylark sounding rocket was first flown as part of the UK space programme in 1957. Still built in the UK, the last was launched in 2005 in Sweden showing that UK rocketry didn't die in 1971!
If you're stuck for something to do, follow my posts on Twitter. I link to interesting new electronics components and development kits (some of them available from my employer!) and retweet posts I spot about robot, space exploration and other issues.
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This is great. I work in the field of Ecology using these devices with weather balloons (use hydrogen as well, helium just costs too much) could be a cheap way of getting large scale distribution of animals data directly in real time. Even better a controlled blimp??