Engineering tomorrow

The biggest challenges facing engineers are the same today as they were 30 or even 130 years ago: namely, to produce commercially viable products that customers wish to purchase at minimum cost and which involve the least possible wastage of energy. The Cover Story of Eureka's very first edition in December 1980 was about producing three-dimensional woven composites with the goal of saving weight and thus fuel costs in aerospace. Thirty years later, these are commercially available for use as manhole covers and are beginning to be used in aerospace, and there is an enormous amount of research aimed at their wider use. But it has taken a long time to get there. The technique described in the article was based on the use of a 'Tablet loom', originally said to have been developed in ancient Egypt more than 6,000 years ago and there is an argument to say that most things in mechanical engineering have been invented before. This may be true, but if engineers want to search to see if a suitable idea to solve a design problem has been developed before, they can now make use of something that did not exist 30 years ago – the global Internet and the exploding power of information technology. For the first time in history, engineers can instantly collaborate, and companies compete regardless of where they are on the planet. And once something is invented, there is no way it can be lost or uninvented. The result is an unprecedented explosion of ideas and developments that makes it possible to for engineers across the world to solve the problems of how to provide enough energy and personal transportation to meet the demands of the world's growing population without wrecking the climate. Hopefully, these developments will not take the 30 years it required to make 3D composite weaving commercial, but if there is one lesson to be learned from study of the innovations reported by Eureka over the years, it is the time and the pain that it takes to get real innovation to market. There is no shortage of examples. In December 2003, we published a cover story about the development by Southside Thermal sciences of ultraviolet pulsed laser fluorescence technology for measuring the temperatures of novel ceramic coatings on ground and aircraft jet engine turbine blades so they can safely be run hotter. On October 26th this year, the company announced that it had just successfully conducted a gas turbine engine test on a Rolls Royce Viper 201 engine as part of the project, 'Sensor Coating System SeCSy', which is co-financed through the Technology Strategy Board, in cooperation with RWE npower, Land Instruments and Cranfield University. Apart from the article in Eureka, the company has won various awards, but is still at the stage where it has to say 'STS is looking for potential partners to market this novel coating technology'. Remote measurement capability is up to 1550°C, ±5°C. In some fields, however, when driven by powerful demand and strong market forces, things can happen somewhat faster. The clearest example of this can be found in the field of computing. CAD in 1980 was crude and unwieldy and most engineers still designed on paper. In December 1980, Eureka published 'Software explosion makes tools out of toys'. Until this point, many engineers wrote their own applications using BASIC. Graphical CAD was unknown to most people and a Commodore PET, Apple or Tandy with 16, 32 or 48K of memory plus a printer would set you back £2,000. Collaboration was by personal contact or by mail. Now, 3D CAD modelling and global collaboration are universal. Elsewhere in this issue, Bernard Charlès, the CEO of Dassault Systèmes, is predicting that we shall all shortly be designing in a truly lifelike virtual reality environment and that 3D printing of prototype parts will in five years time be as common as colour printing is today. 3D CAD and 3D television are already with us, but there are at least three competing technologies that allow users to see 3D images without the need to wear glasses. One involves the creation of holograms – truly 3D images that hang in space. The main barrier until now has been the amount of data that has to be streamed to reproduce the necessary number of hogels – 3D holographic pixels. Another technology that is imminent is parallax barriers – a system of precision slits in front of a 2D display in the Nintendo 3DS, which is to be launched in Japan in February 2011. Finally, there are systems based on microlenses, where an array of lenses forms an array of images, and projecting them back through a similar array reconstructs the image in 3D. According to NPL, which has put much effort into the microlens element, the idea was first proposed by Gabriel Lippman in 1908, who called it 'Integral photography'. Used for years to make 3D greetings cards, we have seen various demonstrations of it in conjunction with LCDs. In addition, a company called Real3D was set up by Ivor Lanzman in 2007 to exploit a system that combines microlenses in front of a Fresnel lens array to project 3D advertising images. A convincing demonstration was shown at this year's Venturefest in Oxford. Electronic control, too, was in its infancy in 1980. Now, anything with an engine is computer controlled to optimise efficiency and performance and silicon chips manage most domestic appliances. The explosion in electronic control can only continue. How long do we have to wait for computers to safely steer and brake our cars as well as manage the engines and braking systems? This is hard to say, but the capability is there and the research effort is massive. Even a blind person has been put behind the wheel of a car on a test area in the US (Virginia Tech), although not yet on the public highway. Airline pilots routinely let computers fly their machines, although nobody has yet had the nerve to take them off the flight deck altogether. Meanwhile, robotic unmanned aerial and underwater vehicles are a fact of life with the military. Latest developments, so far only trialled as computer interfaces for the disabled, require users only to look where they want to go, and control by thought is far from impossible. Clearly, one of the biggest philosophical changes of the last 30 years has been the quantum shift in prominence of environmental concerns. In just three decades, the environment has transformed from a peripheral, minority issue to the driving force underlying much of modern design and research. The need to meet the aspirations of a rising world population, with limited and finite fossil fuel reserves, coupled with a concern not to render the planet uninhabitable has – to say the least – focused minds. One area that has seen this change more immediately than most has been the automotive sector. After decades of stagnation in design, motor vehicles are transforming rapidly. Hybrid vehicles are commonplace, battery electric vehicles are making a comeback in new forms and millions of motor vehicles with conventional engines in a number of countries have been converted to run on methane from natural gas, rubbish or sewage, or ethanol. Designing a vehicle to run on alternative fuels is said to add around €50, which is much less expensive than a lithium ion battery pack. Fuel consumptions per mile driven for conventional internal combustion engines are vastly better than they were, and are predicted to halve again in the next several years. The quest for renewable energy has thrown up a range of candidates to meet our future energy needs. Biogas has already been mentioned and the other alternatives are well known: nuclear, nuclear fusion, wind, solar, tidal, wind and wave. In nuclear, fast breeder cycles that make full use of uranium and thorium cycles are rearing their heads again. Nuclear fusion, on the other hand has not become anywhere near commercial in the last 30 years, and is still not likely to have solved all its technical problems in the next 30 years. Wind energy is turning out to be expensive as well as intermittent but it maybe that the way forward is small scale but with much cheaper devices. This, at least, is the opinion of Matthias Luethi, a finalist in the 2009 British Engineering Excellence Awards, who has set an eventual target manufacturing cost for his 'Silent Wind Turbine' at £100, including generator. As regards solar photovoltaics, 1980 saw the first cell exceed 10% efficiency and total world production was around 4MW peak. Today, top efficiency is 40%, total world production around 7.3 GWp – 5.6GWp of which was in Europe – and prices continue to fall year on year. However there is a way to go yet. Average total world power consumption is 15TW. The amount of solar energy reaching the surface of earth is around 90PW, where 1PW = 1000TW and 1TW = 1000GW. Most of this solar energy is, of course, not directly accessible. The UK is at present world leader in wave and tidal energy, which are more accessible, especially round an island. UK Tidal energy may have taken a knock with the decision not to go ahead with the Severn Barrage, but this does not affect projects such as SeaGen's tidal generator in Strangford Lough. Professor John Kemp's OWEL – Offshore Wave Energy Limited, which has waves compressing air as they move along a narrowing chamber in a free floating vessel, is now at the stage of design and construction of a 600 tonne demonstrator. The search for alternative sources of energy has also taken some unexpected and exciting turns. For instance, humble wireless switches are now on sale that are powered by the user actuating them, and the next stage, we are told, is devices that are powered purely by the heat generated by the user. Based on Siemens technology, but spun out in 2001, the wireless switch technology is now the property of EnOcean, headquartered in Oberhaching, near Munich (the name referring to a perceived ocean of available energy). When the switch is depressed, a magnet is flicked in a coil by an ingenious spring mechanism to induce a pulse of electricity sufficient to send a 125 kbit/s digital 868 or 315 MHz wireless message in the space of 30ms. Each switch comes with a unique 32-bit identification number to prevent overlap with other switches. This does away with the need for wires or passing current through the switches. If this were not enough, EnOceans' Zeljko Angelkoski said at the Energy Solutions show that the company is in the process of commercialising devices that could be powered by temperature differences of only 1 to 2°C. The breakthrough is in DC-DC converters that start operating at 20mV, producing 3.4V. Coupled to a Peltier element, this means that heat from a human hand or body could be made to produce about 1mW, sufficient for a wireless medical monitoring system. A US competitor is Nextreme Thermal Solutions, with its 'eTeg' HV56 thermoelectric.?This produces 1.5mW and an open circuit voltage of 0.25V from a temperature difference of 10°C in a footprint of 11mm2. Eneco, headquartered in Salt Lake City, spent some years developing thermionic diode semiconductor devices that turn very low grade heat into electric current with somewhat greater efficiencies than is possible with Peltier devices. While the company filed for Chapter II bankruptcy in January 2008, the IP was purchased by some of the shareholders and development has restarted in Texas under the name MicroPower Global. There is also a related MIT based venture called Micron-gap ThermalPhotoVoltaics. Another approach, described in Eureka in January 2007 is 'Power Chips', a Georgian-invented quantum effect technology relying on the difference in the functions of smooth and textured surfaces. Whoever wins this race, it seems likely that within a few years, mobile communication devices will cease to need mains charged batteries; instead, they will be powered by the heat generated by their users. Furthermore, it is likely that solid state devices will be able to recover energy from low and high grade heat sources. Materials, too, continue to advance and over, the next 30 years, we can expect even more developments. For instance, the last 30 years has seen nanotubes go from exotic phenomenon to a product that is commercially manufactured in tonnage quantities. The next 30 years is likely to see the same thing happen to graphene nano platelets and also an even more exotic idea: to produce useful human replacement organs from constructions engineered from grown tissue. Perhaps more than anything, this technology gives some idea of the almost limitless scope for progress. For some time, been realised that growing human spare parts from stem cells is far in the future, so researchers are looking at ways of constructing organs from assemblages of different cells. Here, the UK is taking a lead with expertise in the hands of Professor Mehdi Tavakoli at TWI, in his capacity as programme manager for the Health Technologies KTN; and Paolo Madeddu, professor of Experimental Cardiovascluar Medicine at the University of Bristol and the Cardiff Institute of Tissue Engineering and Repair. Predictions for the next three decades • Real innovation in the UK will continue to be time consuming and painful • CAD and television will be true 3D without glasses. Before the end of 30 years, design will be conducted in virtual worlds • Cars will, when required, drive themselves. The preferred fuel will be methane derived from biogas, but vehicles will be capable of being run on anything that will burn. Organic rubbish will be a commodity with value • Medical monitoring devices and probably mobile phones will be powered by human body heat. They will no longer need to use any mains power to recharge batteries. • Most of the technical problems to providing world wide 'green' energy will have been solved. Nuclear, low cost small scale wind and photovoltaics, tidal and wave power will all play their part. Low grade and high grade heat will be increasingly directly converted to electric power by solid state devices. It seems likely that fusion power will still remain a goal that lies 30 years in the future. • The miracle engineering materials will be based on graphene. Carbon nanotube based materials will have become commonplace. • Replacement human organs will be constructed by engineers from biologically grown parts