Some futurologists call the “internet of things” a phenomenon that will revolutionise the way we live. Cynics call it the latest marketing techno-trend.
On a practical level, the internet of things (IoT) is the integration of sensors and wireless communications into millions of everyday objects and devices, so they can send and receive data. The number of potential applications in different products and sectors is exciting and daunting. From the condition monitoring of machines in industry, to that ubiquitous IoT example, the smart fridge that orders its own milk, the prospect of new features and services mean that device by device the IoT is being built. By 2020, US market analysis firm International Data Corporation (IDC), predicts there will be
212 billion “things” around the world connected to the internet. And that’s at the conservative end of analyst’s predictions.
While consultancies fawn over large numbers and even larger future profits, a factory near Stuttgart, Germany, continuously produces more and more of the building blocks of the Internet of Things, without which this global technological revolution could not happen.
Bosch’s Reutlingen factory produces MicroElectroMechanical (MEMS) sensors and is expanding fast. According to consultancy IHS, it is the
top supplier of MEMS sensors in the world. Every second smartphone worldwide uses Bosch sensors.In total Bosch has produced four billion MEMS sensors since it started manufacturing them for the electronic stability systems of cars in 1995. Some 1.4 billion of that four billion were produced last year at Reutlingen. The sector, Thorsten Mueller, chief executive of Bosch Connected Devices and Solutions, modestly says, is growing “apace”. But just 20 years ago, Bosch was the only company in the world producing MEMS sensors. Mueller says: “The sector's growth was driven by the automotive sector. But we had to make them cheaper, and separate it from the automotive electronics division to be a forerunner with the technology. By 2005 we had a broad experience and were looking at adjacent sectors, like healthcare and consumer electronics.”
Micro mechanical systems are built on thin silicon wafers with a diameter of eight inches
The company’s experience in integrated circuits and engine management was a good head start, but MEMS are much more sophisticated, and the company has invested heavily over the years in R&D, particularly in human capital and clean rooms. Most recently in 2009 the company invested €200m at Reutlingen, for the plant to expand into future predicted capacity. It surprised some that the plant would be set up and expanded in a high cost location in Germany. But, says Mueller, this is so that engineering and manufacturing can be situated close together, “as this is how the innovation happens”.
“Today, the challenge is still to make the sensors cheaper, but also to drive down costs and power consumption and to make them thinner with a smaller footprint. Engineers are also integrating more functions into one sensor module,” he says.
MEMS can carry out a variety of functions more effectively than their micro counterparts
MEMS are between 0.02 to 1.0mm in size and are made up of even smaller mechanical and electromechanical components and a microprocessor that processes the data. They are mostly made from silicon. However, in contrast to silicon-based semiconductors, which work at the top of the wafer with slight trenches, MEMS need deep trenches to be etched.
When MEMS were first fabricated in the late 1980s they were produced using X-ray radiation and galvanisation. But in order to scale up production to higher volumes, engineers have adapted similar processes and clean room manufacturing environments used in the production of semiconductors, with commercial machines. One of these production methods, deep reactive ion etching, has proved so successful it is widely-used throughout the industry and known as the “Bosch process”.
The Bosch process and other manufacturing technologies have been licensed out. The company has followed a strategy of partnering with other companies and has partnerships with LG, ABB and Cisco. The number and nature of IoT applications is so large and diverse, the partnerships help devise products and services to get the markets moving, says Mueller.
“We have developed the sensors, the software and the services. You need all three for success. Our software innovations focus on the cloud, linking devices to smartphones to generate value. The services are for the customer, where they realise value.
We have this in-house but have opened this up to external partners as well, in order to realise the full market potential, to grow the markets. “
The component parts in MEMS can be as small as 0.001 mm
However, powering devices loaded with sensors remains one of the largest challenges. Most devices that make use of these type of sensors are by their nature mobile or deployed in a network, most probably both. “It’s a barrier because you do need a lot of know-how to optimise,” says Mueller. “It's relatively easy to integrate the modules and realise prototypes. But if you want to be professional about it you should involve our company. You have to have a deep insight into the sensor systems in order to optimise it fully for power.”
The power required to run the sensors mean engineers have been forced to look for new sources of power. The most promising is the technique of energy harvesting. Solar cells is the most developed technology in this category, although engineers are also making good progress with thermal and vibration energy harvesting, says Mueller
Partnerships are not the only way strategy though. The company also showcases its expertise in micro-mechanical sensors within its own range of garden and household appliances and tools. Hundreds of miles away, at a lawnmower factory at Suffolk in the UK, is the other end of the MEMS sensor manufacturing chain. The Indego autonomous lawnmower is packed with MEMS sensors so it can move systematically around a garden lawn. The mower has a navigation system that calculates the most efficient way to cut the lawn line-by-line. It has safety and security sensors - the bump sensors use magnetic fields to detect the boundaries of its mowing area and there are sensors on its axle that also used in emergency braking systems.
The Stowmarket factory is making 650 Indegos per week, around 15 per hour on a 47.5 hour single shift. Two hundred components from all over the world go into each Indego. The electronics board come from Penang and the software and test equipment from Bangalore. The high level software design comes from Germany. Each mower and its sensors are comprehensively tested in a cell before boxing up, making the Indego production line significantly more complex than other parts of the factory.
The Indego seems ahead of its time, a strange thing to say about a lawnmower admittedly. But it is a symbol of the commitment the company has made to rolling out micro-mechanical sensor technology and connectivity into its products. Peter Fouquet, President of Bosch in the UK, says: “The internet of things is the future for many companies. But to us everything can be equipped with sensors, from the milk carton to the jumbo jet. There are around six billion sensors already installed in devices around the world and the number is growing. It’s a strategic imperative for the business.”
MEMS sensors are the hidden innovation within our cars, phones, increasingly in our home heating and security systems - the unseen building blocks of the Internet of Things. People take it for granted that smartphone displays orient themselves to how they are being held, or auto adjust their brightness. The latest cars bristle with sensors, for automatic emergency stops, parking, cruise control, stability and suspension as well as inside the engine. With the level of innovation and manufacturing taking place at the world’s number one production of MEMS sensors and a cooperative spirit to grow the market, it seems their prevalence in our everyday lives is only set to grow.