Continuous communication with Mars

Researchers in Scotland have discovered a way to enable continuous communication from Earth to Mars, making manned missions to the red planet slightly more plausible.

The technique, which was investigated by engineers at Strathclyde University, would allow continuous communication with one spacecraft.

It was previously believed this was not possible because the Sun obscures the Earth’s view of Mars for several weeks at a time. This would prevent any possibility of ground controllers making contact with astronauts.

The Strathclyde research centres around Lagrange points - five areas in space where an object such as a satellite or observatory can stay fixed in the same location relative to the Earth and Sun. The team has investigated how emerging space technologies can be used in Lagrange points one and two to open up new possibilities for future missions.

Malcolm Macdonald, the leader of the research, said: ‘By moving a spacecraft with a continuous thrusting propulsion system into Lagrange point one, we’ve calculated that it’s possible to enable continuous communication from the Earth to the spacecraft and from the spacecraft to the surface of Mars.

‘We’ve also shown that by using a similar technique but with two spacecraft, we can further improve communications. Hovering directly above Mars limits communications to just one polar region. But by using two spacecraft, we can enable communication to a much wider area of the planet.’

The research was based on potential evolutions of the T6 Thruster technology being developed for the European Space Agency’s BepiColombo mission to Mercury, due to set off in 2014.

Macdonald continued: ‘Currently, every spacecraft we have is in orbit about Mars. But this is not necessary - we can use the Lagrange points and low-thrust propulsion to keep spacecraft in a fixed position.

‘Our research has shown that we have a whole catalogue of space-science opportunities available in the next ten to fifteen years by using technologies that are already in the pipeline. This can include everything from new space missions to continually monitoring the effects of climate change on the arctic. Our aim is to challenge conventional ideas and enable radical change in the near term.’

Macdonald’s team carried out the research at Strathclyde University’s Advanced Space Concepts Laboratory, European Space Agency’s European Space Operations Centre and Glasgow University. The work was funded by the European Space Agency’s General Studies Programme.

The team’s findings are being released this week at the 60th International Astronautical Congress, the world’s biggest space conference, being held in Daejeon, Korea. It is part of a €100,000 (£92,440) study funded by the European Space Agency to investigate how new and emerging technologies could be used to radically enhance space science, from greatly improving telecommunications to enabling Arctic monitoring.

Source: The Engineer Online

Carbon nanotube conductors

Researchers at the Honda Research Institute USA, with support from academics at Purdue University and Louisville University, have been assessing nanotubes and their potential to transport electricity faster over large distances with minimum energy loss.

The carbon nanotubes may open up new possibilities for more powerful and compact fuel cells, energy storage materials and hybrid vehicles.

Grown on the surface of metal nanoparticles, they take the form of rolled honeycomb sheets with carbon atoms in their tips.

Researchers at Purdue University used a transmission electron microscope to observe nanotube formation, revealing that changes in the gaseous environment can vary the shape of the metal catalyst nanoparticles from very sharp faceted to completely round.

Further work carried out at Louisville produced the nanotubes in larger volumes and made measurements to determine whether the nanotubes achieve a metallic state.

According to the researchers, the carbon nanotube formation revealed metallic conductivity that was significantly stronger when compared to steel, had higher electrical properties than copper, was as light as cotton and could conduct heat as efficiently as a diamond.

Dr Avetik Harutyunyan, principal scientist from Honda Research Institute USA, said: ‘This is the first report that shows we can control fairly systematically whether carbon nanotubes achieve a metallic state. Further research is in progress with the ultimate goal to take complete control over grown nanotube configurations to support their real-world application.’

Dr Harutyunyan added: ‘Our finding shows that the nanotube configuration that defines its conductivity depends not only on the size of the metal nanocatalyst used to nucleate the tube as was previously believed, but, importantly, is also based on its shape and crystallographic structure, and we learned to control it.’

Up until now, research had focused on the structural formation of carbon nanotubes with metallic conductivity through conventional methodology resulting in a success rate of around 25 to 50 per cent. Honda claims that it has achieved a success rate of 91 per cent metallic conductivity.

Dr Hideaki Tsuru, project director from Honda Research Institute USA, said: ‘Our goal is not only the creation of new and better technologies and products, but to fulfil Honda’s commitment to environment sustainability.’

Source: The Engineer Online

Smart electric drives to improve

Smart cars may offer improved electric drives in the future, following real-life trials being conducted for their manufacturer, Mercedes-Benz.

Elektromotive, a Brighton-based provider of electric-vehicle (EV) recharging stations, has been selected as one of the UK companies trialling the Smart electric drive.

The trial will test Smart cars in ‘real-life’ situations that will give Mercedes-Benz the necessary data to shape the development of the vehicle.

Mercedes-Benz have provided Elektromotive with a fully electric Smart to use over the next four years. Following this, Elektromotive will report back on the car’s battery performance, reliability and range.

The information will be evaluated by Smart as it moves towards small series production of the Smart electric drive in 2010.

Elektromotive believe the trial will also add to its ongoing research and development programme, helping it devise EV charging facilities for installation at the roadside, in car parks, at homes and in business premises.

‘The shift towards zero emissions motoring is fast gathering pace and it is vital that fully compatible recharging infrastructures for EVs are put in place across Europe,’ said Calvey Taylor-Haw, Elektromotive’s managing director.

‘With daily access to a smart electric drive we will accelerate the real-world evaluation of new charging technologies, such as fast-charging solutions for passenger cars and light commercial vehicles.’

The Smart electric-drive car, developed by Mercedes-Benz, is powered solely on electricity and charged using a standard three-pin plug. The almost silent, non-emitting, two-seater vehicle has a range of up to 70 miles and a top speed of 60mph.

Dermot Kelly, managing director of Mercedes-Benz UK, said, ‘The smart electric-drive project is an important part of our commitment towards developing sustainable transport solutions across the Mercedes-Benz business.

'Smart continues to be a pioneer in the world of environmentally friendly and economical driving and we’re delighted that Elektromotive is our partner in this exciting electric car trial.’

Source: The Engineer Online

UAV flies using fuel-cell system

A small unmanned aerial vehicle (UAV) recently completed 23 hours of uninterrupted flight using an advanced fuel-cell system.

The US-based developer of the system, Protonex Technology, claims that the flight of the Ion Tiger UAV breaks an unofficial endurance record for fuel-cell-powered flight.

The flight was documented by the US Naval Research Laboratory (NRL) through a programme sponsored by the Office of Naval Research (ONR).

It is claimed that the 23-hour-plus duration of the Ion Tiger flight surpasses all previous small UAV flights using any technology.

The Protonex power system is said to have given the Ion Tiger seven times the endurance capability of advanced batteries.

The system used in the Ion Tiger demonstration is an ultra-light proton exchange membrane (PEM) fuel-cell system, coupling stack technology that can reportedly achieve 1,000W/kg with a specially designed balance of plant components.

Following this recent demonstration, Protonex is planning to transition its systems into small UAV products for both military and civilian applications.

The company believes that there is a market opening for such products because endurance capabilities demonstrated in its programme were only achievable with larger-scale, more costly UAVs.

‘This impressive 23-hour record flight milestone represents yet another successful collaboration with the NRL and is a culmination of all of our combined efforts to date,’ said Dr Paul Osenar, chief technology officer of Protonex. ‘We share the ONR’s vision towards bringing quiet electric propulsion and long endurance to today’s small UAVs and to extend the capability to the warfighter.’

Source: The Engineer Online

Sensor increases target accuracy

Lockheed Martin has completed a successful test of its first 360-degree infrared sensor turret aboard its Desert Hawk III unmanned aircraft system (UAS).

The hand-launched Desert Hawk III is designed to operate in extreme temperatures and high altitudes and has provided the British Army with critical intelligence, surveillance and reconnaissance (ISR) capabilities in Iraq and Afghanistan.

According to the company, the addition of the infrared sensor will allow troops to obtain greater target location accuracy and improved image stability.

The infrared sensor will be used alongside an upgraded 360-degree colour electro optic (E/O) sensor, providing 10 times continuous zoom capability and aiding in contact identification.

John Nikolai, director of electronic products and logistics at Lockheed Martin’s Tactical Systems business in Eagan, said: ‘To assist the warfighter, we have miniaturised the infrared payload, so it fits into a turret weighing less than two pounds.

‘The E/O camera has been upgraded as well, for improved target identification. With the introduction of these sensor capabilities, users will experience vastly improved night-time situational awareness.’

The Desert Hawk III consists of a lightweight, hand-launched air vehicle with snap-on Plug and Playloads, a portable ground station and a remote video terminal. The UAS’ payload capability means that sensors can be changed in less than one minute to meet rapidly changing mission requirements.

Currently, the Desert Hawk III provides five modular capability payloads including a 360-degree turret with a mix of E/O and/or black and white low-light imagers, an infrared stabilised imager in a roll axis out to 90o, a signals intelligence sensor, the new 360-degree infrared sensor and the upgraded 360-degree E/O imager.


Source: The Engineer Online

Peugeot announces green initiative

PSA Peugeot Citroën has unveiled an action plan to limit the carbon footprint of its vehicles during their service life.

The group plans to increase its use of green materials in the polymers used to build the cars to 20 per cent by 2011. This will include the use of natural fibres such as linen and hemp, non-metallic recycled materials and biomaterials that are produced using renewable resources rather than with petrochemicals.

Peugeot’s cars are currently made up of 70 per cent metal, five per cent miscellaneous materials, five per cent fluids with the remainder plastics.

Peugeot hopes its initiative will use fewer fossil-fuel plastics and increase the use of raw materials from renewable sources. In addition to reducing CO2, it claims the change will make the parts lighter and promote plastics recycling within the industry to reduce the potential impact of end-of-life vehicles.

The use of bio-materials is still at the research stage in the automotive industry. To speed up the use of these materials, the industry has set up scientific partnerships as part of research groups bringing together laboratories, chemical firms and parts suppliers.

The company believes that as a result of its plan, 85 per cent of all of its vehicles can be reused or recycled, and a further 10 per cent could be used for energy recovery. The initiative will also focus on existing vehicles with green materials being integrated during their production life. The group’s engineering teams are working with suppliers to implement the changes.


Source: The Engineer Online

Gapless Points for safer railways

Gapless railway points that could ensure the safe rollout of high-speed trains are being developed by a former Oxford University tutor in collaboration with ISIS Innovation.

The gapless rail arrangement has been designed to replace existing points used to route railway traffic. Developer John Lucas claims that his design will reduce wear on the railway track, allowing trains to travel at much higher speeds while minimising jolts to improve passenger comfort.

His concept is based on the pivoting movement of railway flanges to the side of the fixed rail and along the railway track. This movement causes the whole rail to move forward and engage at the apex of the crossing where the two inner lines join. The top of the moving blade goes over the sharp apex to form a firm join with the fixed rail going out.

Conventional points systems in the UK only move sideways, leaving a gap between the blade and the fixed rail. Lucas explained that this gap, which can be as wide as 4in (10cm), restricts the maximum speed of the train.

‘If you have a heavy train and the wheel crashes onto the apex of the join, this puts greater wear both on the rail and on the wheels, meaning that they’ve got to be repaired more often,’ he said. ‘This also increases the risk of an accident and quite a lot of the accidents that have occurred both here and abroad have been on account of points failure.’

In the past five years, two major accidents involving fatalities at Potters Bar and Grayrigg in Cumbria have been attributed to points failure. Lucas believes that accidents such as these could be prevented by eliminating the gap in the points to reduce the risk of derailment.

He also claims that the benefits of high-speed rail in the UK will be significantly reduced if railway points are not upgraded alongside high-speed lines. ‘With my system, there are no real limits to speed,’ he said. ‘There will be other engineering problems. For instance, in the extreme case of something that is meant to deal with trains going 250mph, the moving blade would weigh about four tonnes and this is something we’ll have to solve.’

A similar device for high-speed rail, called the swingnose crossing, was developed by researchers in the US. This system eliminates the gap by moving the point of the crossing from side to side in time with the selected direction of change. British Rail trialled the design for a short period, but rejected it in favour of the current system due to safety concerns and the high cost of its rollout.

Lucas is confident that his solution can overcome the problems associated with the swingnose design. ‘The swingnose has the pivot where all the wear is, so you have a greater likelihood of failure. My design is more robust in this respect. The swingnose also needs two movements to be coordinated, whereas my device needs only one, so you reduce the possibility of error there.’

He is working with ISIS Innovation to further develop the system and attract industry partners for commercialisation. The team is in the process of developing the safety systems and reducing the risk of false alarms. The design is currently subject to a UK patent application.

Ellie Zolfagharifard


Source: The Engineer Online