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Faculty of Mechanical, Maritime and Materials Engineering.

New grab unloads vessels faster and smarter

There was plenty of reason to celebrate for transport technologist Dingena Schott and her team at TU Delft. Not only did they develop a design method for a new grab, but the grab, built by Nemag, complied with all of the predictions generated by the models, tests and simulations that they validated. ‘There is no precedent for this in the scientific literature. It’s definitely the crowning glory of our work,’ says Schott. This Dutch grab could potentially unload vessels in ports all over the world more efficiently and sustainably. Dingena Schott Every day, huge vessels from Brazil and Australia enter the port of Rotterdam with thousands of tons of iron ore, coal and other dry bulk. Here, crane operators ensure that the cargo is emptied quickly and efficiently, so that it can be stored or distributed to smaller vessels that then transport it via the Rhine to steel factories in Germany and Austria. To unload this kind of cargo, a crane operator has a variety of grabs to choose from, depending on the kind of dry bulk. ‘The question is: do they have the ideal grab for the product they want to unload?’ says Dingena Schott, who is doing research at the Department of Maritime and Transport Technology at the 3mE Faculty on new technologies for port-related transport logistics. ‘The most recent design for grabs is approximately fifty years old. Since that time, no fundamentally new designs have come onto the market.’ So does this mean vessels can be unloaded more quickly so that they can leave the port earlier to pick up the next load? Video created by Stef Lommen Schott thinks so. What’s more, the research that she and her team conducted has already led to an innovative grab that reduces the unloading time of a vessel by at least ten per cent. TU Delft developed the models, the insight and the design method for this, and worked together with grab manufacturer Nemag from Zierikzee, which created the new design. On 13 November, Nemag even received a prestigious award, a prize given by the International Bulk Journal for the most innovative technology for cargo handling. At first sight, the new grab doesn’t seem that much different than existing grabs. All grabs have two shells with a hinge in the middle and a closing mechanism. ‘The aim is to get as much material as possible per grab,’ says Schott. ‘The amount is limited by the crane on the quay, which can only lift up to a certain weight. If you go for a really heavy grab, then it will of course penetrate deeper into the materials, but it can’t take as much per grab. So the ideal grab is as light as possible but can still dig itself in well. It’s kind of a trade-off between mass and force.’ But where do you start when you want to improve a trusted grab in the conservative world of handling and storing bulk? ‘Since 2007, we have been using discrete element software as part of an innovative design method. Since the arrival of this technique, we have been able to understand for the first time exactly what happens when materials are grabbed. It makes it possible for us to model iron ore pellets as well as the grab, monitor their behaviour in a simulation when the pellets are grabbed, and thus determine whether the grab is being filled optimally. Initially we modelled and tested with an existing grab at Tata Steel in Ijmuiden in order to validate the model.’ Thanks to the software, Schott and her team can compute exactly how much force is needed to grab as many pellets of iron ore as possible. ‘In order to be able to move the grab you have to pull the cables at the top. Then the grab tries to close, but because of the resistance of the iron ore, it will become slower and slower. To maintain the same speed, you then have to pull harder on the cables,’ says Schott. To understand the dynamics of the grab together with the iron ore properly, she connected the dynamic grab model to the discrete element model. The difference between the existing and the new grab is in the overall design: both the new mechanism and the new shape of the shell ensure that the ratio between the forces exerted and the filling of the grab is optimised. That’s what ultimately makes it possible to unload a vessel in ten per cent less time. It’s already a considerable improvement in efficiency. In addition to the productivity, which has increased by 10 per cent, the grab also weighs 15 per cent less. As a result, fewer scarce raw materials are needed. Moreover, vessels don’t stay in port as long waiting and unloading, which reduces emissions. But it could be even more effective. Schott’s aim is to speed up the unloading process even more in the future by creating a dynamic grab capable of adapting itself. Moreover, it’s not just about the grab, but also the crane onto which the grab and cables are attached. ‘We only changed the grab design now, because we couldn’t change anything at the top of the crane yet,’ says Schott. ‘But actually we shouldn’t only be perfecting the grab, but also its interaction with the crane.’ Currently a PhD student is developing models for other kinds of bulk materials. The properties of a material, such as the shape of the particles, their texture and stiffness, mean that each material ‘behaves’ differently. This affects the flow inside the grab. Think, for example, of dry sand, which flows more easily than wet sand. ‘By analysing all kinds of substances, we can develop the grab even further. Ultimately, of course, we want a grab that performs optimally for all products and under all conditions.’ Read the press release by Nemag: 'Nemag wins the prestigious IBJ Award with the nemaX®

Thinking and talking like a doctor and a technologist

Thinking and talking like a doctor and a technologist First graduating class of bachelor students in clinical technology New technologies, such as 3D printing and sensor chips are changing medicine. But we can do better when it comes to surgical lights and stethoscopes, for example, as the theses of the first graduating class of bachelors students in clinical technology demonstrate. They want to make the lives of surgeons, doctors and patients easier with new technology. Surgical wrist light The brainwave came when she was sparring with a group about their final assignment, says Tessa van Hartingsveldt, who had just earned her BSc in clinical technology. Despite special surgical lights, surgeons still complain about a lack of light. Their own heads and hands create shadows. ‘We figured out a way of having the light come from underneath the hands,’ says Van Hartingsveldt. This resulted in a prototype of the surgical pulse light: a series of LED bulbs beneath the pulse. Initial tests show that they do indeed provide more light, exactly where it’s needed. For three years now, TU Delft, Leiden University and Erasmus University have been instructing students together in medicine and technology in the clinical technology bachelor’s programme. This has occurred on request of the care sector. Medical technology is playing an increasingly important role in hospitals, rehabilitation clinics and nursing homes. ‘It’s necessary too, because of the ageing population, a lack of staff and the rising cost of care,’ says Arjo Loeve, lecturer and researcher in biomechanical engineering at TU Delft and coordinator of graduations projects. ‘An operation theatre without a clinical technologist is going to become a rarity. He or she will make sure that the technology is used exactly how it should be.’ Bilingual As a clinical technologist you really have to be a jack-of-all-trades, Loeve adds. ‘You play a role that bridges technology and medicine. That means that you have to be excited by “hard technology”, but also that you need thorough knowledge of medicine and the language that doctors speak.’ All of these requirements seem to have come together in the final projects, a kind of master test. For example, one group of students delved into sound technology in order to ‘isolate’ the classic stethoscope. Following a major accident or tragedy, the surrounding noise can be deafening, so imagine trying to pinpoint a weak heartbeat or crackles in the lungs. Another group delved into bot replicas from a 3D printer. When do potential form deviations occur during production, and how extensive are they? The students started to work with scan techniques, 3D printers, measurement techniques and statistics, and they developed a test model to assess the various techniques. ‘The deviations turned out to be minor, a few tenths of a millimetre,’ Ysbrand Willink says,’ and they mainly arise in the printer.’ Paul Roos says that ‘dental surgeons can definitely use the models while preparing for an operation, but they are not suitable for forensic research. The difference between a saw or knife trace on a bone vanishes with a replica. The “copies” are ultimately useful as replacement bone.’ The mortal remains can perhaps be passed on to the survivors while the evidence remains intact. Isolated stethoscope Isolate stethoscope research in anechoic chamber ‘Common’ problems Clinical technologists also have to be able to establish contact with patients, emphasises Lex Linsen, head of Student Education at the Department of General Practice at Erasmus MC. Linsen is the creator and coordinator of the class called ‘Van inleving naar innovatie’ (From empathy to innovation). Students meet a chronically ill patient and come up with an idea of how to help him or her. ‘It’s not about a revolutionary operation technique for parap legia but more about providing help for everyday, bothersome problems,’ says Linsen. ‘Innovation not because it’s possible, but because it’s necessary.’ Linsen has approached patient associations to ask whether there were people with a chronic affliction willing to participate. Students Paul Roos and Amne Mousa, for example, spent a day with a peer suffering from hydrocephalus. They learned, among other things, that these patients have to visit the hospital a few times a year because the pressure on their brains either increases or decreases. When that happens, the drainage speed has to be adjusted. That means a small hole has to be drilled into the skull. Roos and Mousa presented a potential solution to this problem: place a pressure sensor in the valve of the drain so that drilling will no longer be necessary. ‘Brilliant,’ says Linsen. ‘And the neurosurgeons agree. Their immediate reaction was: why didn’t we think of that ourselves?’ The smart-drain isn’t a reality yet, Linsen emphasises. It’s still an idea, an initial design. But hopefully that will lead to a prototype and ultimately to a smart drain that can actually be used. Pioneers On 12 October the more than forty clinical technology students that completed their studies will receive their degree. How does it feel to have been in the very first graduating class? ‘Because you’re the very first,’ Van Hartingsveldt says, ‘there aren’t any practice tests yet. And in the beginning we were often cramped into a lecture room. The three scheduling systems with three universities didn’t work very well yet. But on the other hand there were great opportunities because we were the first ones. For example, we got to witness open-heart surgery. That was really special.’ ‘Everything is new for lecturers too,’ Willink says. ‘That’s why they’re really open to ideas and criticism. That enables you to shape your own education a little bit as well.’ A study with three partners also generates interesting contacts for lecturers, Loeve says. ‘I talk to doctors and researchers that I previously never encountered. That has already led to new partnerships in research.’ That includes institutions outside the Medical Delta, by the way. The final projects also included clients from the AMC and the Jeroen Bosch Hospital. ‘My call for project ideas,’ Loeve says, ‘reached many people by word of mouth, including ambulance services and rehabilitation centres. That’s really great.’ And the reactions to the research work have been full of praise, Loeve says. ‘Doctors are genuinely surprised and impressed by what these students have conceived and implemented in such a short period of time.’ ‘Some doctors had to get used to the idea that a non-doctor was getting involved,’ Van Hartingsveldt says. ‘But I mostly encountered enthusiasm in the hospitals, and people that wanted to talk to us and cooperate with our research.’ Delft-Leiden-Rotterdam The clinical technology bachelor programme is training a new kind of medical professional: an academic with thorough medical and technical knowledge that builds a bridge between the technology and doctor and patient. The programmes began in the academic year of 2013-2014 with a hundred students a year who were admitted via a selection procedure. The Delft University of Technology is coordinating the programme. The partners are Leiden University (LUMC) and Erasmus University Rotterdam (Erasmus MC). Care institutions associated with the Medical Delta are also cooperating. The first forty bachelor graduates received their degrees on 12 October 2017. The future: technical medicine Bachelor graduates in clinical technology Paul Roos and Ysbrand Willink joined the new three-year master programme in technical medicine this September. This bilingual MSc programme provides an opportunity to study medicine and medical technology in more depth. There are two specialisations: Imaging & Intervention, which focuses on imaging techniques, and Sensing & Stimulation, which focuses on tracking and monitoring the health conditions of patients. Anyone with a BSc in clinical technology can also opt for a master in one of two basic disciplines: medicine or biomedical engineering. Those wanting to continue in medicine are required to follow a transition programme. Tessa van Hartingsveldt is considering the master programme in biomedical engineering. ‘The engineering side of it is what appeals to me most. But first I’m going to take a gap year and work and travel.’

Predicting waves at sea

Predicting waves at sea She had already walked onto the deck, the person who had to wave a little flag in eachhand for the helicopter pilot so he would know exactly when to land his aircraft on theship. At the same time, a crane operator was fastening his hook to the place where hewould lift the foundation for an offshore wind turbine. Later he would carefully put itoverboard at the designated place on the bottom of the sea. Elsewhere, another ship wasready to lower a small pilot boat into the water, which would pilot a freighter into theport later that day. All three were looking at the app which has already been commonly used in the maritime industry for some time now: the wave radar. Thanks to this technical gadget, developed by Peter Naaijen, assistant professor of shipand offshore hydromechanics at the Delft University of Technology, everyone at sea cansee whether there are waves in the vicinity in the coming five minutes and how the shipwill respond to them. The neat thing about this new technique is that essentially allships already have radar navigation. Naaijen analyses this radar data, which containsinformation about the location and height of waves. Thanks to his innovation, it hasbecome considerably safer to perform offshore operations. Peter Naaijen image: Jort van der Jagt To a certain extent, wave conditions at sea are already predictable, except these predications are not very specific. ‘They are not that useful, because you want to know exactly where these waves are and when they are coming,’ Naaijen says. Indeed, this knowledge is reducing accidents in the offshore industry: helicopters are ceasing to crash on ships because the deck unexpectedly comes closer and from now on heavy loads can be transferred from one ship to another without them colliding and causing damage. In addition, installers of wind turbines no longer have to wait until the sea is calm again, nor will they have to travel back to the coast because the waves are too high to work in. It is even possible to find a window when it is momentarily calm during bad weather. This saves downtime, on the one hand, the time that ships need to stay ashore and, on the other hand, it ensures that ships do not set out to sea without accomplishing their mission. This saves both time and money, but also fuel. The margins in the wind industry are small,’ Naaijen says. ‘You gain lots of hours by not having to wait and having more hours per day and more days per year to carry out your offshore operations.’ Predicting waves is similar to predicting rain. ‘Compare it to a weather report for the Netherlands that predicts a thirty per cent chance of rain. You cannot be sure exactly where and when this rain is going to fall. A rainfall radar provides more location and time-specific data, which will give you a better chance to avoid getting soaked. That is why the rainfall radar is a good comparison for our wave radar. During my PhD research I showed that it is possible to predict how high waves will be around a ship 2.5 hours in advance,’ Naaijen says. Whether or when a ship leaves port is determined by the ‘sea state’, a kind of coefficient that reflects the intensity of the waves, just as the Beaufort scale does for wind. ‘Imagine that a wave three metres high is the absolute limit for an operation that takes two minutes. A ship will not leave port at sea state 4 because the chances of encountering a three-metre wave are too high,’ Naaijen explains. ‘But in reality 93 per cent of that time consists of intervals of at least two minutes, during which the height of three metres is not reached! So if you know exactly when to expect those high waves, then you can avoid that moment and there will be plenty of time left to safely finish your job. That means you can potentially achieve huge savings because ships can leave port more often during higher sea states and do not have to wait on shore as long.’ Difficulties with working on board because of high waves How exactly does this wave radar work? Most ships already have all of the necessary hardware for predicting waves, and so the technology does not require a major investment. ‘We use the radar navigation on ships. Right now, it indicates where other boats are located and precisely where the coast is, so that ships do not run aground,’ Naaijen says. ‘But actually the radar receives a great deal more information, namely where all of the waves in the water are located.’ This is how it works: a radar transmits electromagnetic waves that collide with the waves in the sea, so that the antennae receives them back again. Right now, that information is being filtered out, because it is not interesting for sea captains. ‘We tap into this raw radar data, so that we can analyse it with all kinds of intelligent algorithms. So we are essentially using a waste product.’ In the meantime, Naaijen has launched a company called Next Ocean with a former fellow student, and he has received a grant from the Netherlands Organisation for Scientific Research to actually develop the wave radar app. ‘Parties from industry, such as Boskalis and Allseas have encouraged me to translate my research into a product, because there is great demand for this in the offshore world,’ he says. The first customer has already been announced: Allseas will be the first company to equip its ships with the Next Ocean Wave Predictor. ‘That is what we decided to call our software, but actually it is more of a ship motion predictor,’ Naaijen says, smiling proudly. He expects the software to be ready in late 2017. In 2018, offshore workers on ships should be able to see how high the waves are on mobile devices, so that they know when the best time is to carry out their work.’

A thrilling nail clipper

A thrilling nail clipper Engineering for forensics A good nail clipper can mean the difference between a murderer behind bars and one on the loose. ‘You can have the best high-tech machinery in your forensic laboratory, but if you’re not able to enter the right evidence into it, you’ll never find the perpetrator.’ Cotton swabs, tape and tweezers are important tools for forensic investigators. Gathering evidence at the scene of the crime is done manually. ‘Low tech. And there’s nothing wrong with that,’ emphasises researcher Arjo Loeve, project leader of Engineering for Forensics at TU Delft’s 3mE. Loeve loves technology, but also simplicity. ‘The simpler the instrument, the easier it is to use and clean. And that also reduces the chances of contamination.’ But low tech certainly does not mean that the work is easy. Forensic investigators have to make quick decisions under time pressure. Where are traces of evidence likely to be found? How can we secure it? After all, the scene of the crime can be a busy motorway, a cramped cellar space or a beach at low tide. Experience and expertise play a key role. ‘That’s precisely why I believe that engineering can make a major contribution,’ Loeve says. ‘By developing more reliable or faster instruments, but also through modelling. What, for example, is the most efficient sequence of action for gathering evidence in a given setting?’ Textile polyester fiber with trace material Stamp with adhesive tape for collecting traces Loeve, who trained as a biomedical engineer, ended up in forensic research more or less by coincidence. ‘I had an exciting conversation at a birthday party with someone from the Netherlands Forensic Institute.’ The talk led to a joint research project. They wanted to figure out how serious the risk of DNA cross-contamination is during physical examination following a sexual offense. Cross-contamination is the unintentional and undetected ‘transfer’ of DNA from one place to another during the investigation. Loeve experimented with true-to-life models in the laboratory and was shocked by the findings. The probability of cross-contamination using the classic method – speculum and cotton swab – was more than sixty per cent. ‘And to think, finding the perpetrator’s DNA on or in the victim can ultimately mean the difference between acquittal and conviction.’ So it’s high time for a new method. ‘We developed a ring with a kind of plastic bag on it that shields the cotton swab. There wasn’t a single incidence of cross-contamination in ninety tests that we performed in the laboratory. We hope that it will be field tested soon.’ More research projects soon followed. Together with the Academic Medical Center and NFI, Loeve is trying to more accurately predict the victim’s time of death. ‘Right now, there’s often still a margin of error of hours. We think we can reduce that to less than half an hour with new sensors (TU Delft) and calculation models (AMC) that take into consideration body weight and a variety of environmental factors.’ Loeve also developed practical tools for forensic investigators who have to wear an airtight suit at dangerous crime scenes. Some of the research projects clearly have common ground with Loeve’s biomedical research. One example is a study on abusive head trauma, the damage that babies suffer as a result of violent shaking. ‘In order to acquit or convict people, we need more knowledge about what kind of damage is caused by shaking as opposed to falling, for example,’ Loeve says. ‘And of course that would also make it possible to give parents better advice.’ Loeve is using knowledge from other ongoing research on how and when bones break for this study. ‘Increasingly I’ve noticed that our medical and forensic research projects have common ground and even overlap.’ Series such as CSI and NCIS were a huge success. How exciting is Loeve’s ‘crime lab’? ‘We don’t do investigations ourselves at crime scenes or in real cases. I do talk a lot with forensic investigators and read case reports to get a good idea of what happens in the field.’ Loeve stresses that these never involve ongoing cases. ‘And believe me, I’d rather not have been exposed to some of the details. Anyone who thinks that the writers of these series have a morbid imagination are wrong.’ The knowledge in the files may be shocking, sad and intense, but that’s also precisely what drives Loeve. ‘It does make it clear that you’re contributing to something important. Unfortunately there’s a need for what we do.’ What’s needed, for example, is the new nail clipper that Loeve designed with his students and NFI. The prototype was extensively tested in the laboratory and is ready to be field tested by the police. ‘A nail clipper doesn’t sound very sexy or exciting,’ Loeve says, laughing. But you can find traces of the perpetrator or victim’s DNA under nails. Or material that reveals something about recent activities or the environment that he or she was in. The new Delft nail clipper makes it possible to clip the nails of a stiffened fist without having to bend the fingers. The nail cannot jump away while being cut. And you can easily replace the front with a clean part. It makes it easy to clip the left and right hand individually. ‘Knowing that something was done with the left or the right hand can turn out to be crucial evidence,’ Loeve says. What was the most difficult part, technically speaking? ‘There wasn’t really a eureka moment. We adapted the design step by step until all of the requirements were met. We aimed for the simplest possible tool that could be cleaned easily and quickly, which you could use with two hands in all situations.’ It’s especially important, when developing a new tool, to be able to let go of ideas and listen closely to what’s really needed, according to Loeve. ‘The simplest solution often turns out to be the best.’ Arjo Loeve Co van Ledden Hulsebosch Center TU Delft’s 3mE Faculty has been an official partner of CLHC, the Co van Ledden Hulsebosch Center, since last year. This research consortium in the forensic sciences was established in 2013 by scientists from the University of Amsterdam, the Amsterdam Medical Center (AMC) and the Netherlands Forensic Institute (NFI). It is named after the first Dutch forensic scientist Co van Ledden Hulsebosch, who co-founded the International Academy of Criminology in 1929. Loeve is the coordinator at Delft. ‘CLHC provides additional contacts and expertise. This kind of consortium is satisfying: short lines of communication with all kinds of scientists and meetings where you speak to new people and share problems.’ Lowlands Crime Lab A ‘murder’ was committed by science 175 times during Lowlands 2016. It all happened in the Crime Lab set up by the Amsterdam University of Applied Sciences, TU Delft, the Police Academy and NFI. More than six hundred festivalgoers participated. Almost two hundred of them smothered, with painted hands, a mannequin head with a pillow, which yielded 175 pillows with ‘choke traces’. Before the murderers had a go at the mannequin head, they put a pillow case neatly around the pillow, also with painted hands. Arjo Loeve was there: ‘That allowed us to examine whether there is a recognisable difference between regular depression marks and marks caused by violence.’ Online forensic engineering course Forensic investigation is used in many more places than you would think. For example, forensic engineers are called in to analyse all kinds of situations in which technical systems have or seem to have failed. Examples include gas extraction in Groningen, aircraft crashes or patients in hospitals who are infected by bacteria that are transmitted through surgical instruments. Together with Karel Terwel (civil engineering) and Michiel Schuurman (aerospace engineering), Arjo Loeve set up a massive open online course. This free course, entitled ‘Forensic Engineering – Learning from Failures’ can be found at and will start in mid-October.

New watch mechanism out of a single piece

New watch mechanism out of a single piece Innovation from the lab into the real world Nima Tolou, a researcher and entrepreneur at Delft, is very proud of a new development in the core of mechanical watches. In a close cooperation with the LVMH Watch Division (TAG Heuer/Zenith) and Flexous, a start-up from TU Delft that he co-founded with physicist and entrepreneur Oleg Guziy, he used his expertise in compliant mechanisms and MEMS technology to co-develop a watch with a totally new time mechanism. Along with this, he’s working on another innovative device that converts vibrations into free energy. Nima Tolou ‘For me, an innovation is not complete until the finding actually works in the real world. In other words, outside the lab,’ he emphasises. But the real world is often stubborn. Unexpected problems emerge that ruin even the most fabulous innovations. A great discovery can end up in the archives of science, carefully described in a paper or patent. That’s very important but for Tolou not enough. ‘As a child I made my own toys. At school in Iran I regularly won awards for my creations. I’m a thinker, a designer, but definitely also a maker.’ Tolou is convinced that the developers themselves know and understand their technology better than anyone. ‘In case of the watch, we started all over many times. You don’t give up easily when you’re convinced that there’s a solution. The faith that it can work is a key aspect of the development.’ Flexible The size of the control mechanisms in watches has been considerably miniaturised since Dutch scientist Christiaan Huygens invented the pendulum in 1675, but the principle hasn’t changed. The pendulum in the clock, or the spring drive in a watch, ensures that the hands always indicate the right time through a complex system consisting of many parts. But Tolou, who has a background in physics and mathematics, together with the LVMH Watch Division and Flexous, discovered an alternative. Most mechanical systems consist of rigid structures , usually metals. Think of the wheels, pinions and bearings. Tolou and his research team specialise in micro mechanisms that contain flexible, elastic components, referred to as compliant micro mechanisms. In other words, matter that gives, bends, quivers or vibrates. The team discovered that a single circular part with complexly shaped cut-outs can combine multiple essential functions that take more than 30 parts in a conventional watch. This new approach, along with smart use of the nonlinear nature of compliant mechanisms, lead to an innovative mechanical system that is more accurate, more precise and more energy efficient at the same time. The other advantage of this idea is that with high precision production techniques, this kind of watch mechanism can be etched from a single flat piece of silicon. And it will be simpler, small, maintenance-free and robust. Tolou was convinced that you can apply these compliant micro mechanisms in a watch. Who dares to realize such a wild idea? Mechanical watch makers tend to fancy classical craftsmanship. After 3 years, the TU Delft team, Flexous and the LVMH Watch Division, managed to realise this. The product was introduced by LVMH to the market on 14 September 2017 under the name Zenith Defy Lab as “the world’s most accurate mechanical watch”. Zenith Defy Lab Watch With 15Hz Movement Is 'World's Most Accurate' | aBlogtoWatch A series of publications provided general knowledge about the accurate design of oscillators in compliant mechanisms and lead to the granting of two Best Paper awards at international conferences in France (MARSS) and the United States (ASME IDETC). Free power A second finding by the Delft researcher is about to be made public: an energy harvester. It’s a device that harvests energy when it vibrates after passing of a car, for example, or because it’s standing on a machine. The crux of the discovery, however, lies in the use of extremely small, flexible components that makes the device sensitive to low frequencies and irregular vibrations. ‘It’s about mass on specially shaped elastic material,’ Tolou says. ‘This mass starts to move as a result of vibrations, and we subsequently convert this movement into power.’ The prototype looks like a thick classic battery (size D). ‘But one that charges itself,’ Tolou says. The energy harvester can provide sensors with power and make it possible to send data. And these types of sensors are becoming increasingly prevalent. There are expected to be twenty billion of them in the world in just a few years’ time. ‘Nowadays we connect all devices to each other: the Internet of Things. Our environment is becoming increasingly interactive,’ Tolou says. Sensors that derive their energy from vibrations don’t have a plug. Their battery lasts ‘forever’. That makes them considerably less expensive, particularly in hostile environments and places that are difficult to access where battery replacement is inconvenient or expensive. Tolou’s energy harvesters are therefore useful for monitoring moving objects: sea containers, sheep in mountainous environments or a stolen bike. But they’re also useful for detecting forest fires or the sound of illegal chainsaws in the rainforest. You simply hang the sensor on a drooping branch. Most of all, Tolou hopes to make the world a little bit safer, more efficient and more productive . For example, sensors on railway tracks or train wheels that automatically warn you when a train is approaching. And many more sensors on industrial estates. ‘If sensors are inexpensive and can function independently, then you can attach them to every storage tank, pipe, pump and valve.’ Overheating will be signalled in good time and maintenance will be carried out based on measurements instead of annual cycles. ‘What’s more, you’re doing all this with energy that would otherwise be wasted,’ Tolou explains. Free and environmentally friendly electricity in other words. The amount of power generated by his energy harvester is limited to a maximum of 10-20 milliwatts, however. ‘Not enough to charge your mobile phone, in any case. For that you would need to fill your backpack with harvesters. Which isn’t very practical, of course.’ Thanks to the unstoppable rise of sensors, harvesting energy from our environment has become a hot field of research with a great deal of competition. So what is it that makes Tolou’s discovery so promising? ‘Our energy harvester can convert fast and slow vibrations into power. In many other systems, the vibrations have to be within a specific range. But it makes no difference with our system whether you are cycling quickly or slowly over cobblestones.’ Also in this case the breakthrough was generated because of the combination of thorough knowledge (the Veni-award of Tolou) and his drive to turn innovations into products. Gap Tolou is working on new products with the spin-off company Flexous that he co-founded in early 2014 with physicist and entrepreneur Oleg Guziy. Tolou is technical advisor, Guziy CEO. The division that focuses on marketing the motion energy harvester has been named Kinergizer. “Flexous bridges the gap between academy and production. If you introduce your idea to the world by means of a patent license, it will take years before you actually have a product. If you work on the development as an inventor, as a fundamental researcher, then it will happen more quickly, in two to three years’ time. But most of all, I want to be involved in it all, contribute by thinking and acting myself . The process is at least as exciting as the end result.’ Tolou certainly proved that with the recent products. What will his next project be? ‘I’m focusing mainly on research on autonomous systems: self-sufficient electronics. Devices that observe autonomously and subsequently respond to their environment. And they can do that thanks to an energy harvester. Nima Tolou (1982) studied applied mechanical design in Iran. He has been working at TU Delft since 2008, first as a PhD student, and now as a university lecturer. ‘I wanted to continue doing research, but the opportunities were limited in Iran.’ Tolou searched for a reputable university in the area of applied research. He actively seeks partners in the business sector to convert findings and research results into products with his own team.

Using chemistry to close the CO2 cycle

Create fuels out of it, with the aid of green electricity If we want to make the world more sustainable, then we need to find a solution for CO2. Professor Wiebren de Jong (TU Delft) from the Department of Process & Energy (Large-Scale Energy Storage section, LSE) is working hard on this problem. He wants to capture emissions from fuels and other bulk chemicals. A project will be launched in April to convert that into formic acid. De Jong sees opportunities for the long term for transport fuels and the storage of sustainable electricity. It’s the problem of our time: carbon dioxide (CO2). Carbon dioxide is released when we burn gasoline, diesel, gas or coal, and it accumulates in our atmosphere. There it acts as a warm blanket that raises the planet’s temperature and disrupts the climate. ‘If we want to address the climate problem, then we need to handle CO2 in a smarter way,’ De Jong says. ‘The key to a sustainable future lies in closing the CO2 cycle. By making fuels out of CO2 again, for example, or raw materials for industry.’ That makes sense, but it’s going to take serious technological development. The problem is that in chemistry this essentially harmless, colourless gas is a kind of terminal destination. The CO2 molecule is highly stable, and anyone intending to do something useful with it will have to put a great deal of energy into their effort. Figuratvely speaking, but also literally. Indeed, chemists are pretty jealous of nature. Plants use sunlight to produce sugars from CO2 and water, and from there they subsequently produce yet other substances. So it’s possible to use CO2, the only problem is that biological photosynthesis is not easy to replicate chemically. That’s why Wiebren de Jong has opted for a different approach. ‘There is an increasing amount of sustainable energy available in the form of electricity, derived from solar panels and wind turbines. In the future, we’re going to use that green electricity to drive chemical processes that convert CO2. That’s how we can produce fuels from CO2 again.’ Professor Wiebren de Jong was appointed full professor of large-scale energy storage at the 3mE Faculty’s Department of Process & Energy. Several months prior to that he was also named part-time professor of integrated thermochemical biorefineries at the University of Groningen. Wiebren de Jong is an expert in the areas of thermal & chemical conversion and biorefinery. De Jong has been affiliated with TU Delft since he started conducting research for his PhD in 1996. Storing electricity If De Jong pulls that off, he will kill two birds with one stone. First, it will make transport by lorry, ship and aeroplane much more sustainable. ‘Electric power is too heavy for that, and the range is too small,’ De Jong says. ‘With “CO2 fuels” in the tank, the transport sector can create a closed CO2 cycle relatively easily, without having to make huge investments or changes.’ The second, equally important application, is derived from the fact that the processes De Jong is working on essentially store electricity in the CO¬¬2 fuels. This makes it possible to create a balance between the supply and demand of green energy. After all, the production of green electricity is rarely equal to demand. A solar cell delivers electricity when the sun is shining, but people only turn on their lamps once it has gotten dark. If you generate electricity with a wind turbine, it would be great if you could use it when there’s no wind. On top of that, production and consumption always have to be in equilibrium in the electricity grid. There’s little point propping a country full of solar cells if no one is consuming all that electricity on sunny days. ‘It’s crucial for a stable sustainable supply of electricity that you can store green electricity,’ De Jong says. ‘Of course that can be partly achieved with batteries. But chemical storage in CO2 fuels makes it possible to store electric energy on a huge scale.’ A plant running on CO2 fuels can then deliver supplemental electricity during those moments when solar cells and wind turbines are not producing enough. ‘This enables you to buffer supply and demand,’ De Jong says, ‘and reduce your dependence on conventional energy sources, such as coal and nuclear energy.’ Moreover, he adds, the CO2 fuels can also play a valuable role in ‘linking up the seasons’. For example, it would be possible to ‘save’ sustainable energy from the summer (sun) and autumn (wind) until the winter, when houses need to be heated up. Once CO2 has entered the atmosphere it’s not easy, chemically speaking, to use it anymore. ‘The concentration is 400 ppm,’ De Jong says, ‘a few hundredths of a per cent. That’s too high for the climate, nor is it optimal in terms of process technology.’ Indeed, he sees possibilities for using CO2 that is released in high concentrations, for example in power plant chimneys, waste incinerators and steel plants. Another possibility is to allow trees and plants to grow (because they absorb CO2) and subsequently use the biomass. Indeed, Wiebren de Jong is devoting a great deal of attention to that, in particular when it concerns the use of organic by-products. From lab to factoryDe Jong’s research is characterised by the ambition to ‘make something that works,’ as he puts it. His room borders the process hall with the ‘skids’: the technology set-up where new processes are developed and researched. ‘This is where ideas are transformed into reality,’ De Jong says. ‘We take what was conceived in a lab and carried out on a small scale in a fume cupboard and elaborate on it here in such a way that industry can really do something with it on a large scale. That means making optimal use of the thermal effects from the chemical conversion, for example. That’s how we create an integrated process that is essentially ready for large-scale use.’ The industry, or research institutes such as TNO and ECN, with which De Jong frequently collaborates, can then take the developments at the pilot plants to the next level.We have not reached this stage yet in the area of CO2 conversion. You can convert CO2 into CO with electricity, he explains. Carbon monoxide is much less stable and can therefore serve as a starting point for the synthesis of fuels and chemical raw materials. As is often the case, this is all easier said than done. Efficient electrodes are needed to introduce electric energy into the reactor; the CO2 has to be dissolved in the reaction solvent; good catalysts are needed; and it’s still a challenge to direct the complex interaction of chemical reactions is such a way that you end up with the desired product. ‘Still plenty of work to do,’ De Jong summarises. The 3mE Faculty’s Process & Energy Lab, which has just entered its second year, is the hub for all of TU Delft’s large-scale research in the area of process and energy technology. It is the only one of its kind in the Netherlands. The research being conducted at Delft in this area takes place in six sections: intensified reaction and separation technology; energy technology; large-scale energy storage; fluid dynamics; multi-phase systems; and engineering thermodynamics. Formic acid An interesting example of the use of CO2 is its conversion to formic acid. That is a ‘fuel’ for battery-free electric cars, but also a sustainable raw material for the chemical industry. The latter is keen to become ‘greener’ and is therefore prepared to invest. ‘Of course, the knowledge that we are developing,’ De Jong says, ‘is important for the real large-scale processes that will take place in the long term, such as the production of transport fuels and “sustainable natural gases”.’ A special project was launched in April 2017 in which De Jong further developed the path from CO2 to formic acid together with TNO (project coordinator), start-up company COVAL Energy, Manure Processing Fryslân BV , and CE Delft. The FAST student team from Eindhoven, which developed a car based on formic acid, was involved as well. So far, the research has generated a prototype the size of a paving stone. ‘Now it’s important to push the process in a direction where it becomes relevant for industry. That means, among other things, bigger electrodes and higher pressure, for example. Together with TNO and in close collaboration with the Voltachem platform for electrochemical conversion, we are going to find out what that means for process technology.’ Formic acid An interesting example of the use of CO2 is its conversion to formic acid. That is a ‘fuel’ for battery-free electric cars, but also a sustainable raw material for the chemical industry. The latter is keen to become ‘greener’ and is therefore prepared to invest. ‘Of course, the knowledge that we are developing,’ De Jong says, ‘is important for the real large-scale processes that will take place in the long term, such as the production of transport fuels and “sustainable natural gases”.’ A special project was launched in April 2017 in which De Jong further developed the path from CO2 to formic acid together with TNO (project coordinator), start-up company COVAL Energy, Manure Processing Fryslân BV , and CE Delft. The FAST student team from Eindhoven, which developed a car based on formic acid, was involved as well. So far, the research has generated a prototype the size of a paving stone. ‘Now it’s important to push the process in a direction where it becomes relevant for industry. That means, among other things, bigger electrodes and higher pressure, for example. Together with TNO and in close collaboration with the Voltachem platform for electrochemical conversion, we are going to find out what that means for process technology.’

Mechatronics 2.0: sustainable form of all-in-one

The Netherlands is good at mechatronics, the multidisciplinary field centred on integrated mechanical systems that carry out their work by means of a clever combination of sensors, actuators and control engineering. Just Herder, professor of interactive mechanisms and mechatronics and new chairman of TU Delft’s Department of Precision and Microsystems Engineering, likes to look into the future, at what is unofficially called ‘mechatronics 2.0’. Whereas the elements of mechatronics have traditionally been separate entities, Herder is trying to integrate these elements with each other to the fullest extent possible. ‘We can do it on a smaller scale and with more precision, using fewer materials and less energy.’ Crowd surfen Why does a mobile phone have separate parts to process zeros and ones, to probe the outside world and to emit a vibration?’ Herder asks. His research group is attempting to integrate different functions with each other in a smart way. An important advantage of this approach is that it is highly suitable for miniaturisation. And that is how Herder found himself in the magical world of nanotechnology. ‘If we want to continue to make increasingly small computer chips, then the machines that do it are going to have to become more and more precise as well, without their energy consumption going off the charts.’ Herder imagines a point on the horizon in his field of research: ‘Now that chips are being produced with the precision of a millionth of a millimetre (the scale of the nanometre), we also have to start thinking about transformations at the nanoscale in the moving container that transports the chip from A to B during the manufacturing process. An actuator layer between the container and the chip can compensate for transformation at the nanometre scale in the container, thus protecting the chip. But would it also be possible to completely replace the container with thousands of miniscule fingers, which allow the chip to crowd surf with the highest possible accuracy? Perhaps these fingers could inspect the chip in the meantime too.’ Manufacturing and controlling these kinds of smart fingers is one of the single biggest challenges for the new mechatronics. Pliable Elastic mechanisms with extremely low stiffness are an important tool. Replacing traditional mechanical systems, for example based on layers, with pliable alternatives will create a material surface onto which active layers can be placed. Electro-active polymer layers, for example, can act as sensors and piezoelectric layers as actuators to generate movement. Thus movement, actuation and sensing would be combined in one continuous structure. This structure wastes less energy and is also easy to scale down. ‘This is another way of looking at mechanical engineering equipment,’ Herder says. ‘At the moment equipment is being made that is increasingly large in order to achieve greater precision, and for that reason they use up more space, material and energy.’ Energy harvesting A special property of mechanisms with extremely low stiffness that is being studied in Herder’s group is the fact that they can be used to ‘harvest’ energy in slow movements. ‘Think, for example, of a sea container,’ he explains. ‘In order to figure out where it is located, you would basically want to build a GPS tracker in it that emits an occasional signal. But you want to avoid having to constantly replace the batteries. A simple mechanical system that gets energy out of the movements that the container makes while it crosses the ocean does not need a battery.’ The applications are countless, and Herder is working in close cooperation with industrial partners. The spin-off company that emerged from Herder’s research on flexible mechanical parts, Flexous BV, has already launched a subsidiary company called Kinergizer BV that focuses specifically on energy harvesting applications. Autonomous microrobots ‘In five years,’ Herder says, ‘I hope we will have succeeded in fully integrating these low-stiffness mechanisms into microelectromechanical systems (MEMS), manufactured by means of prevailing chip manufacture techniques. ‘If we can apply these commonly used techniques to also build integrated MEMS/mechatronic systems, it will open up a whole world of opportunities.’ During the same period, he expects advances to take place in the area of bio-inspired robots, which can manoeuvre autonomously through unstructured environments, such as certain organs in the body, in order to inspect them around the clock for long periods of time. ‘Nature does not use propellers to generate movement through a fluid. Instead, this task is performed by cilia or flagella. The combination of mechatronics and nanotechnology provides opportunities to build these kinds of systems on the smallest possible length scale. We have already achieved initial results on a larger format. In the coming years I hope that prototypes will be able to move autonomously, similar to the way robot vacuum cleaners do.’ Nano-Engineering Research Initiative Herder is enthusiastic about the potential of the combination of mechatronics and nanotechnology in his department. ‘I think there is a great deal more we can achieve. Innumerable interesting phenomena are there for the taking now that we can inject nanotechnological expertise into the area of mechatronics. It will enable us to produce materials, instruments and equipment that work thanks to nanotechnology (“nano-enabled”), and, conversely, develop machines that produce products on a large scale based on nanotechnology (“enabling nano”).’ Indeed, he has great expectations of the Nano-Engineering Research Initiative (NERI) initiative. ‘The great thing about NERI is that it combines fields of expertise into one department. I have limited understanding of nanotechnology but all the more of automation. For others it is precisely the opposite. The lines are short. We are thinking up the most exotic plans and keep discovering that these plans are actually feasible as long as we do it together.’ In addition to the projects being carried out in partnership with industry, Herder views NERI as a new way of pursuing productive partnerships and safeguarding continuity in the long term. ‘The idea is to provide group support for certain lines of research. Companies from different branches of trade interested in the same research topic join forces. Because the participants have different applications in mind, there is a great deal of leeway for collaboration instead of competition.’ At the moment Herder and his colleagues are very busy with the first NERI contracts. ‘This is the tipping point. NERI will enable us to showcase what we have to offer and what we are worth.’ Prof. Just Herder