Ultra-Wideband is gaining traction: 'accuracy down to the centimeter'
From augmented reality games to automatic car locks: gauging the location of devices is becoming increasingly important in modern life, but the precision we demand is far beyond the reach of GPS or Bluetooth. With the Ultra-Wideband (UWB) micro-location technology from imec, the location of objects in a space can be pinpointed exactly. "Over the coming years, the use of this technology is set to increase dramatically," said Christian Bachmann, imec at Holst Centre's Program Manager Ultra-Wideband and Bluetooth Secure Proximity.
imec is a research and innovation center in nanoelectronics and digital technology. It is part of the FiRa consortium, which is committed to the development and application of user experiences with UWB technologies. Among other things, imec developed a UWB radio chip that can be mass-produced at low cost.
imec's Ultra-Wideband technology is an extremely accurate and energy-efficient solution for locating objects. Bachmann sees the excitement surrounding the technology, that seemed to be 'out of fashion' for a while, coming back again. "The algorithms that the technology uses are getting better and better, and the costs of implementing it into products are getting lower and lower."
From GPS/Bluetooth to UWB
At present, wireless devices are often still controlled by GPS or Bluetooth, but that's not always ideal, as Jason Hillyard, Vice President at Packetcraft, explains. "Imec and Packetcraft are currently working together to integrate Packetcraft's UWB protocol software on imec's next-generation UWB chip technology. I myself drive a Tesla and it has an automatic and wireless lock based on Bluetooth and GPS. If I'm three or four meters away, the lock already opens automatically and my daughter, who might be standing next to the car, can open the car door using the handle. Of course, that's not always ideal. UWB is much more accurate in such a situation and consequently safer."
But UWB contains more unique features. At specific locations, such as indoors, GPS will not work, but Ultra-Wideband does. "For example, think about a restricted, secure, keyless entry," adds Bachmann. "That's where technology can make a big difference. Even controlling speakers and other smart devices in your living room is possible, down to a precise level." In augmented-reality gaming and in robotics, where humans and robots have to work together, the technology is also making headway. Consider the application of UWB in future robotics, applications such as safe human-robot collaboration (co-bots) or automatic navigation for smart indoor farming.
A few selected applications already use UWB technology on a large scale. Apple first introduced the technology in the iPhone 11 series. Via UWB, the iPhone can accurately search for objects using the AirTag as soon as the UWB module in the iPhone is activated.
The technology has also been used over the past year and a half for purposes that Bachmann and Hillyard had never foreseen. "During the COVID-19 pandemic, wireless technology made a significant contribution where social distancing is concerned," says Bachmann. For example, social distancing devices working with UWB have already been tested in the Johan Cruijff Arena.
The COVID buzzer from the Dutch telecom company KPN is a device that vibrates and flashes when someone comes within 1.5 meters of it. "Applications like this would never have crossed my mind before 2020," Hillyard says "Here again, you see that the accuracy of the technology is incredibly important. With GPS or Bluetooth, we would never have been able to tell whether people were keeping one or two meters distance from each other."
A whirlwind of accelerated development
According to Hillyard, UWB will gather a lot of momentum in the coming years. "From a technological point of view, it will start to resemble what we witnessed with Bluetooth: excitement in the technology will be followed by an explosion of new products. We're going to be caught up in a whirlwind of accelerated development." Bachmann is also optimistic about large-scale use of UWB in the future. Although he does have one reservation: there is still plenty of room for technology optimization, e.g., in terms of energy efficiency. "In comparison, Bluetooth uses a few milliwatts, where UWB uses a few dozen to hundred milliwatts. There is definitely still some progress to be made there."
Over the coming period, imec will continue its efforts at Holst Centre to develop new innovations that are key to improving the technology. Bachmann explains: "For example, we are working on new low-power radio receivers and on new algorithms, including techniques to further enhance accuracy. This may pave the way for future applications, such as micro-drones or co-bots that use UWB."
For the time being, UWB technology remains relatively unknown to the general public. According to Hillyard, that's not necessarily a bad thing. "Lots of people just want a gadget or specific application that's cool and works well," says Hillyard. "As long as they experience the positive benefits of UWB, it doesn't matter. It's incredibly rewarding to see the technology you've worked on for so long being used in products that improve people's lives. I'm looking forward to UWB developing even further and to the market widely adopting the technology." Bachmann adds: "As you can see, we are definitely ready to enter into new collaborations with industrial partners.
Wearable devices that enable long-term monitoring
"At imec we already have a wealth of experience in using sensor technology for cardiorespiratory diseases. What we observe, is that early identification of problems or close follow-up during rehabilitation helps to prevent diseases or enhance recovery of the patient. As such, remote monitoring potentially also reduces the cost of care and helps address the shortage of healthcare providers. Our focus at imec is on developing sensor technology for patient-friendly and wearable smart devices, to monitor health over a longer period of time, in real-life conditions," explains Heleen Boers, Biomedical R&D Engineer at imec.
"So, it's a logical step to apply our knowledge in the field of rehabilitation. We found an ideal partner in the orthopaedic department of the St Anna Hospital, with its specialist physiotherapy centre: Medical Sports centre TopSupport. They are the go-to experts for research and treatment of post-operative orthopaedic rehabilitation and sports-related injuries. They had, for some time already, been looking into the possibilities of wearable sensors for data collection, to support their physiotherapists in their work."
Turning data into actionable insights
"Of course, collecting reliable data using connected health solutions is a first step to improving health outcomes. But, once you've captured your data, how do you turn it into actionable insights? You can have piles of data, but that is only of value if you have algorithms in place that can perform different data processing steps and mine the data. Without such algorithms, data is simply a pile of data. That's where we come in. And it's also where we came in to support researchers and specialists at Sports Medical centre TopSupport."
"For motion analysis, we were able to relate the output of body movement sensors to the progress in patient's individual rehabilitation. Importantly, the sensors help us identify the quality of the patient's movement. For instance, to what extent is someone able to bend his knee when carrying out daily activities?"
Monitoring patient wellbeing
Orthopaedic surgeon Rob Bogie at the St. Anna Hospital Geldrop and its orthopaedic and sports centre TopSupport in Eindhoven explains: "We had been busy with sensor technology, to see how such technology could possibly support our therapies. We wanted to use wearable sensor technology to create a more patient-friendly and smarter monitoring solution for use during rehabilitation. This could provide us with real, measured rehabilitation progress before and after knee surgery. And do so over a longer period of time and in everyday situations."
"Our enthusiasm was soon curtailed by our success. We were getting loads of potentially valuable data. The only downside was that we didn't have the know-how to access and manage it all."
"So, we were extremely happy when the opportunity arose to do further research in collaboration with imec. They provided the insights and know-how that we were lacking. Conversely, we provided the opportunity for them to validate their sensor technology."
What imec did
Imec developed and validated algorithms using data from wearable motion sensors. These motion sensors measure the movement of several body segments (e.g. lower leg, upper leg, pelvis). The output of these sensors and algorithms can help to monitor physical function and progress of total knee replacement patients during daily activities in natural surroundings, such as: strolling through the supermarket, walking up and down stairs, getting out of bed or standing up from a chair.
"Our algorithms now accurately characterize the collected mass of raw data. They carry out different data processing steps, from filtering to feature extraction. Once you have such filtered and reliable data sets, they can be mined for actionable insights," Heleen Boers explains.
Bogie on current rehabilitation: "Basically, we tell patients to do a set of exercises. Of course, they also get extensive support from our physiotherapists. But every patient and every knee is different. The use of sensor technology will enable us to move away from a one-size-fits-all recovery plan to made-to-measure therapy that – based on sensor data – can be constantly adjusted as needs be. Data that we gather during therapy sessions and during normal everyday situations will provide value-adding insights. Without doubt, all these advancements will mean an enormous boost in positive outcomes and, by extension, patient wellbeing."
Helping improve quality of life
"What we see is that the outcome of so-called Patient Reported Outcome Measures (PROMs) questionnaires is increasingly important. The PROMs are standardised questionnaires about the effect of the pathology on quality of life. We use them to monitor outcomes and also to reach out to patients with a below average score," Bogie points out.
"The thing is, though, that data acquired by PROMs regards aspects of health that are not 'objectively' perceptible. For example, symptoms and complaints such as pain or anxiety, how one functions at work, during sports activities or at home are very subjective. Such aspects of health are often described as 'quality of life'. But how do you monitor and measure something that is inherently subjective; a patient's quality of life?"
"Solutions with wearable sensors will enable us to derive the quality of movement, which is related to the quality of life. What are the measurable improvements and progress? For example, does the patient's knee flex sufficiently to be able to get into the car. Once we can measure this, everybody concerned in the rehabilitation trajectory stands to benefit: surgeons, physiotherapists, above all, the patient. Not only will we be able to improve our healthcare based on measurable outcomes, such information will also become invaluable in maintaining an affordable and effective health service," Bogie concludes.
"We're now also looking into applying this technology for ankle rehabilitation," Eva Wentink, Principal Scientist and Bio-Medical Engineer at imec points out. "We're developing sensors with multiple parameters to integrate into a brace. In first instance, such a brace will be used for knees or ankles, but there is a huge potential for other body parts as well."
"Parameters like temperature, swelling and range of motion give insight into the healing status of an injury or post-surgery rehabilitation. In fact, parameters measured could provide valuable insights and direct, real-time feedback to the patient on what activities can be performed and when to stop. There is no doubt that such immediate feedback can boost rehabilitation and, by extension, patient wellbeing," Eva concludes.
* Sports Medical centre TopSupport is located in Eindhoven. This expert centre is part of the St. Anna Hospital in Geldrop, the Netherlands.