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Amateur unmanned vehicles pushing the limits on altitude, long range and high speed REACH FOR THE SKY ... and way, way beyond Part 2: By Dr DAVID MADDISON In last month’s issue we told how amateur balloonists, kite fliers and model aircraft enthusiasts are achieving amazing results and setting new records. This month we go even further with model rocketry. 86  Silicon Chip A part from balloons, rockets are the other way to get into space. Some amateur rocketry attempts are very impressive. For an overview of amateur rocketry in the US see “Amateur Rocketeers Reach For The Stars – KQED QUEST” http://youtu.be/nurJm0XkU7I In one example a US amateur, Derek Deveille and his team flew their rocket “Qu8k” (pronounced “quake”) to 121,000ft at a maximum speed of 3,516km/h in September 2011. The rocket was 8m long and 20cm in diameter and weighed 145kg at lift off (see left and right). It took 92 seconds to get to maximum altitude and the total flight time was 8.5 minutes. The rocket, which was launched in the Black Rock Desert in Nevada, was recovered substantially undamaged (except some scaring from aerodynamic heating) about 5km from the launch site. For video of the launch see YouTube video “Qu8k - BALLS 20 - Carmack Prize Attempt - High Altitude Rocket On-board Video” http://youtu.be/rvDqoxMUroA and Derek’s web page http://ddeville.com/derek/Qu8k.html Amateurs putting a man in space? While this article has discussed unmanned aircraft and rockets an amateur-built manned spacecraft is certainly worthy of a mention here. Perhaps the ultimate amateur achievement would be to put a human being into space. This is the objective of the non-profit organisation Copenhagen Suborbitals http://copsub.com/ Their objective is to put a person into space to demonstrate that you don’t have to be a large government or other big budget organisation to do this. Copenhagen Suborbitals have a philosophy of developing simple solutions to complex problems. The rocket engines use ethanol and liquid oxygen and the spacecraft is designed to carry one person into space in a suborbital flight. They have already achieved many firsts such as the most powerful amateur rocket ever flown, first amateur rocket to carry a human-size payload, first amateur rocket to have issued a “main engine cut-off” command and first sea launch of a rocket by a small organisation. One of many challenges for this project was the development of a flight computer system. Each major siliconchip.com.au Anodised aluminium nose cone shroud retainer – attaches with threaded eyebolt Black powder actuated pneumatic cylinder 55mm diam, 150mm stroke using 1 gram of 4F BP Nose cone shroud radio translucent fibreglass Payload section formed by nose cone coupler and piston Fin can welded 6061 aluminium Radial bolt retention for forward and aft closures Recover attachment points dual forged eyebolts GPS antenna mounting plate Igniter installation eyebold – Nylon Fins 6.5mm aluminium 6061 CNC profiled Stainless steel tip Case bonded Fin-O-Cyl Fuel grain – 68kg Progressive burn profile Aluminium nose cone superstructure Shear pins 6 pieces of 3.25mm polystyrene 27kg of shear force per pin Recovery piston Tracking smoke grain Timer mount dual adept g-switch timers Pneumatic cylinder mount Aft closure retains nozzle extends divergence forms vehicle tail cone Isomolded graphite throat semi-bell divergence Phenolic carrier insulates throat from case part of divergence minimises thickness of graphite throat Working components of US amateur Qu8k (“Quake”) rocket which reached an altitude of 121,000 feet and a maximum speed of 3,516km/h – enough to cause aerodynamic heating damage to some components. component such as motor, boosters, guidance system and capsule will have its own computer which will communicate with others via a serial bus. Such computers have to be ruggedised for the vibration, heat, cold and vacuum of rocket flight and are not readily commercially available so Copenhagen Suborbitals decided to develop their own. They chose the Arduino platform as a basis for their flight computers but designed their own ruggedised boards which also included modules on board which would normally be separate in a traditional Arduino system. They designated their system CS-duino. Tolerance for the cosmic rays of space and also vacuum were two particular challenges to be dealt with. Electrolytic capacitors cannot be used in a vacuum or extreme cold so alternatives had to be found. Cosmic rays can introduce unwanted logic states in digital electronics and components cannot be readily shielded. Copenhagen Suborbital determined that a cosmic ray strike can be detected when the current consumption of the computer suddenly spikes. If this happens the computer is quickly rebooted and data variables are restored from non-volatile memory, allowing the computer to continue operation with little interruption. The designers have also chosen older, more rugged components such as bipolar transistors instead of Mosfets. These are more resistant to cosmic rays. Unfortunately, the regulatory regime for rocketry here in Australia seems highly restrictive compared to the US for much more than “toy” rockets with many hoops to jump through and very little to encourage participation in serious amateur rocketry activities. In the ACT, for example, even toy model rocket motors are illegal, let alone serious rocket motors of the type described here (theoretically some may be permitted but none have been “authorised”)! These laws really need to be reviewed to encourage greater Artist conception of spacecraft featuring Copenhagen Suborbital’s HEAT1600 rocket engine. At the top of the spacecraft is the astronaut capsule or MicroSpaceCraft (MSC) and atop that is the Launch Escape System. The escape system is a rocket that will carry the MSC to safety in the event that the main propulsion rocket malfunctions. siliconchip.com.au March 2015  87 Zero-g parabola Space Atmospheric re-entry Booster jettison Drogue parachute 100km Main parachutes Launch (using tower) Touchdown Earth Flight path of planned sub-orbital flight. participation in this hobby. It is hard to think of a more ideal country for this hobby with our wide open spaces. Satellites Amateurs radio operators have been launching their own satellites into space since 1961 when OSCAR 1 was launched. It piggy-backed into space in a NASA rocket and it was a substitute for a balance weight used in the rocket. It was thus built in a very specific shape to replace what would otherwise been a dead weight . However, it is difficult for private individuals or small groups to launch their satellites this way. A carrier frame containing PongSats beneath a balloon. As can be seen, the balloon is already at high altitude. altitude to more complicated experiments such as putting computers with atmospheric sensors and data loggers inside the balls. The ping pong balls are cut in half and then taped together with their payload inside. Each PongSat balloon mission can hold 500 PongSats. See YouTube video “PongSat Mission April 2013” http:// youtu.be/GZobW3nuYNs which features the launch of six balloons carrying 2,400 PongSats to altitudes of between 92,000 and 103,000 feet. To date JP Aerospace has launched over 17,000 PongSats involving 45,000 students and the program is open to everybody and there is no charge to students or schools. PongSat PongSats are not real orbital satellites but do achieve very high altitudes on weather balloons and the air pressure at maximum altitude is only about 1% of what it is at ground level. PongSats can do useful science for young students (or even adults!). PongSats use a ping pong ball as a container for their experimental payloads. Whatever can fit in a ping pong ball can be flown subject to certain restrictions such as no insects or other animals, volatile chemicals and weight below 85g. PongSats are flown free for students by JP Aerospace, “America’s OTHER Space Program”, a volunteer-based DIY space program. Many PongSats have been flown for Australian students. PongSat experiments that have been flown by students include everything from simple ones such as seeing what happens to a marshmellow at altitude or to see if plant seeds remain viable after exposure to cosmic rays at high MiniCube JP Aerospace offers another method called the MiniCube for amateurs to fly their payloads to near-space. This is a box 5cm on each side into which you incorporate your payload package. For a fee of US$320 (currently discounted to US$270) you will be supplied with a MiniCube box into which you install your instrument package and then return it to JP Aerospace for it to be flown. For details see http://www.jpaerospace.com/ JP Aerospace also has an extremely ambitious “airship to orbit” program which involves three different vehicles to get to orbit. Some student PongSats before launch. The contents must fit inside a ping-pong ball and weigh less than 85g. You’d be amazed at just how much can be crammed inside a ping-pong ball . . . 88  Silicon Chip siliconchip.com.au A double PongSat with processor and sensors on one side and a solar panel that tracked the sun in the other. MiniCubes at altitude. An inexpensive way to get a small payload to near-space. The first stage involves an airship of seven times greater volume than the Hindenburg. It will have a crew of three and will ascend to 140,000 feet using a combination of buoyancy and aerodynamic lift, with propellers designed to operate in a near vacuum. This first stage airship will dock with a “Dark Sky Station” permanently parked (floating) at 140,000 feet. It will be a gigantic structure and will act as a way station to space. This structure will also be the place where the third stage vehicle is assembled and its departure point. The third stage vehicle will be an airship of truly staggering proportions, the test vehicle alone will be some 2,000m long to give it the buoyancy to float to 200,000 feet. From 200,000 feet it will use a combination of chemical and electric propulsion to reach orbital velocity over a period of 9 hours. For information from JP Aerospace see www.jpaerospace. com/atohandout.pdf For information from Wikipedia see en.wikipedia.org/wiki/Orbital_airship See also “Airship to Orbit Animation” at http://youtu.be/iA45XcmUB8Q (1P, 2P or 3P) or some intermediate amount such as 1.5P. The first four PocketQube satellites were launched on 21st November 2014. While PocketQubes are not “cheap” they are the cheapest way to get your own satellite into space. CubeSats might cost US$125,000 per satellite including orbital insertion but a PocketQube mission might cost US$20,000 or less, including the cost of the satellite and insertion into orbit if using commercial PocketQube components. That pricing might be too much for most individuals but it is well within the capacity of groups of individuals or associations. Funding could also be by crowd-funding or sponsorship. PocketQube Unlike PongSats, PocketQubes are genuine orbital satellites. PocketQube is a miniature satellite format with a basic unit size of 5 x 5 x 5cm with a mass no greater than 180g. These satellites should not be confused with another miniature satellite format, the CubeSat with a unit dimension of 10cm x 10cm x 10cm. As with CubeSats, PocketQubes come in a form factor of one, two or three units in length $50Sat PocketQubes can also be built very inexpensively if not using commercial PocketQube components. One of the first four PocketQubes to be launched as mentioned above was perhaps the world’s cheapest and smallest operational satellite. It is called the $50SAT – Eagle 2 and despite the name cost about US$250 in parts (of course, this figure does not include the launch cost). Featured in an article in SILICON CHIP in February 2014, it was a collaborative project between Professor Bob Twiggs, KE6QMD of Morehead State University in Kentucky, USA and three other radio amateurs, Howie DeFelice, AB2S, Michael Kirkhart, KD8QBA, and Stuart Robinson, GW7HPW. Its purpose was to develop a cheap satellite platform for engineering and science students and have the students JP Aerospace concept of a 2,000 metre long orbital airship. From its launch altitude of 200,000 feet at the Dark Sky Station it will use chemical and electrical propulsion to accelerate to orbital velocity. This would be by far the largest spacecraft ever flown (but of very low density as it is an airship). siliconchip.com.au March 2015  89 SOLAR CELLS SOLAR PANEL STRUCTURE TOP Exploded view of a PocketQube satellite from commercial vendor of components, Alba Orbital Limited (www.pocketqubeshop.com). The entire satellite is 5cm x 5cm x 5cm. Of course, you can also make your own. We featured the PocketQube in the February 2014 issue of SILICON CHIP. PAYLOAD ADCS* (Altitude determination and control system) COMMUNICATION SYSTEM (COM) FLIGHT COMPUTER EPS (Electrical power system) ACCESS PORTAL STRUCTURE SIDE PLATE SIDE SOLAR PANEL STRUCTURE END PANEL MICROSWITCH ANTENNA develop skills building it. The satellite has two 40mm x 40mm circuit boards, including a PICAXE 40X2 processor, a Hope RFM22B single chip radio and other support electronics. Interestingly, from pictures it can be seen to be using a metal measuring tape for its antennae, a cheap, reliable, innovative and cost effective solution for automatic antennae deployment used on many lower cost amateur radio satellites including Australia’s OSCAR-5 which was built in 1966 but not launched until 1970 (the first amateur satellite built outside of the United States). The $50Sat is built with a PocketQube 1.5P length form factor so its size is 5cm x 5cm x 7.5cm. Professor Twiggs said “We really did not set out to build the cheapest satellite at all, but the idea was to make the simplest possible satellite that still fulfilled all the basic requirements for reliability and two way communications.” “The motto we used was ‘you can’t add simple’ and rather than try to add some grand technical experiments 90  Silicon Chip or payload, we deliberately left them out. We wanted to minimise the risk of anything going wrong in order to prove the PocketQube concept and the more complex the satellite was made the more likely this was to happen.” If you want to see the current location of this satellite go to www.satview.org/?sat_id=39436U It transmits a 100mW signal at 437.505Mhz with a variation of 10kHz up or down depending on the Doppler shift. Its OSCAR amateur radio satellite designation is MO-76 (Morehead OSCAR 76). You can also listen to its Morse call sign with a standard handheld UHF receiver (preferably with a good antenna) when the satellite is 800km away or closer. Apart from a slow Morse Code call sign the satellite also transmits telemetry about its operaton as fast 120WPM Morse and as FSK RTTY. Full information on that satellite including design data and software listings (in case you want some ideas for building your own) is available at www.dropbox.com/sh/ l3919wtfiywk2gf/-HxyXNsIr8 siliconchip.com.au Also flown as one of the first of four PocketQubes on 21st November 2013 was the WREN PocketQube which has a camera and micro plasma thrusters to manoeuvre. As described by themselves it was built by “four guys in a garage”. It has a software package that financial supporters were supposed to be able to use, to control the satellite to take pictures. A pre-launch video of this satellite is on YouTube “Fly a Satellite in Space...Without Leaving Your Couch” http://youtu.be/TVGJqNofibo Aerospace has always been a high risk business, even for amateurs. Unfortunately the WREN satellite never went operational and the organisational web page www.stadoko. de/?lang=en is inactive. Of the two other PockeQubes launched, QubeScout did not go operational and TlogoQube went operational but stopped responding in January last year. As of the new year (2015) $50SAT was still operational. Conclusion This series has presented a brief survey of amateurbuilt high altitude, long range and high speed flight. This included a variety of air and space vehicles such as kites, balloons, fixed wing and rotary winged aircraft and rockets. Nearly all of the achievements would have been impossible or at least much more difficult without advances in electronics and miniaturisation, along with mass production to lower the costs to an affordable level. Some of these technologies such as autonomous flights by multirotor aircraft have the potential to change our way of life. Google, Dominos Pizza and others have long term plans to deliver packages to the home via these aircraft but before that can happen, there are many regulatory and safety issues to consider (you don’t want the delivery vehicle or its payload falling on people or property!). Many of these achievements have been undertaken by amateurs with a can-do attitude, doing whatever it takes and it is hoped that in the future regulations are either maintained (at worst) or liberalised to allow such great amateur achievements to continue. SC siliconchip.com.au IP 100H See the review in SILICON C December HIP 2014 (ask us fo r a copy!) Icom Australia has released a revolutionary new IP Advanced Radio System that works over both wireless LAN and IP networks. The IP Advanced Radio System is easy to set up and use, requiring no license fee or call charges. To find out more about Icom’s IP networking products email sales<at>icom.net.au WWW.ICOM.NET.AU ICOM5001 The ultra-inexpensive $50SAT – Eagle 2. The world’s cheapest functional satellite? Note the measuring tape antenna! FULL DUPLEX COMMUNICATION OVER WIRELESS LAN AND IP NETWORKS March 2015  91