Radar technology helps patients with limited mobility
If you use a wheelchair or have a prosthetic leg, small obstacles can become insurmountable barriers. Now, researchers at Fraunhofer IPA have developed a way to detect uneven ground, tiered levels or steps using radar. The information gained can be employed in orthopedic technology to control and stabilize prostheses or wheelchairs.
Stairs, stony paths and tiered levels – for wheelchair users, these obstacles are often insurmountable. This can also be dangerous for people with leg prostheses as an artificial limb cannot make compensatory movements, unlike a natural knee joint or ankle joint.
Bernhard Kleinert from the Biomechanical Systems Department at Fraunhofer IPA: »The research aimed to turn wheelchairs and prostheses into intelligent systems.« He and his team developed a sensor system that helps to recognize obstacles in good time and overcome them.
Small, light, energy-efficient: radar-on-chip
The central element of this new technology consists in using radar-on-chip sensors to scan the environment. Radar chips have several advantages over ultrasonic or laser sensors (which are traditionally used to control robots): They are significantly lighter and smaller, so they are particularly well suited to applications centered on mobility, and they also function outside of closed spaces. This is a huge advantage for use in orthopedic technology, since patients should be able to use the new features in as many scenarios as possible.
However, these inexpensive radar chips do have a disadvantage: They only have one antenna, which both sends out signals and receives the reflected radar signals. With this configuration, only objects that are directly hit by the radar beam are visible. This means that the reading is only one‑dimensional, which is not enough to locate obstacles.
Signal processing opens up new dimensions
Bernhard’s team used a trick to create a two-dimensional image from the one-dimensional readings. The project leader explains: »Similar to a laser scanner, which scans different points on a surface, we combine several reflections from different perspectives.«
The different perspectives occur almost spontaneously when the radar sensor is moved, for instance when someone wearing a prosthetic limb equipped with a sensor moves. Generating different perspectives is much more complicated when it comes to the sensor integrated into a wheelchair. Here, a mirror helps to direct the radar beam this way and that. With the different readings generated, an algorithm developed by Fraunhofer IPA creates a 2D image of the surrounding, which can be used to precisely locate the obstacle down to a few centimeters.
The experts at Fraunhofer IPA have already patented the procedure. Together with Icelandic company Össur, a leading prosthesis manufacturer, they are now exploring how electronic control of leg prostheses can be improved using the radar images.
In a research project with the Human Engineering Research Laboratories HERL of the University of Pittsburgh in America, Fraunhofer engineers are developing an intelligent wheelchair with movable wheel joints that can even overcome stairs.
Jörg-Dieter Walz | Telephone +49 711 970-1667 | firstname.lastname@example.org
Bernhard Kleiner | Telephone +49 711 970-3718 | email@example.com
Jörg Walz | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA
Jelly with memory – predicting the leveling of com-mercial paints
15.12.2017 | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA
Fraunhofer researchers develop measuring system for ZF factory in Saarbrücken
21.11.2017 | Fraunhofer-Institut für Zerstörungsfreie Prüfverfahren IZFP
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
17.01.2018 | Ecology, The Environment and Conservation
17.01.2018 | Physics and Astronomy
17.01.2018 | Awards Funding