Gabriele Bleser, Bertram Taetz and their team outline the activities on mobile and wearable technologies being undertaken by the research group wearHEALTH.
The research group wearHEALTH is an interdisciplinary team of computer scientists, psychologists, cognitive scientists, mathematicians, movement scientists, and control engineers, associated with the Computer Science Department at the Technische Universität Kaiserslautern since 2014 and working on development based on mobile and wearable technologies.
The team is funded over five years by the German Federal Ministry of Education and Research. Together, they pursue the goal of creating reliable health systems based on mobile and wearable technologies.
• To support individuals in establishing, regaining, or maintaining a healthy and active lifestyle
• To support evidence-based medicine
The team follows a user-centred, inter- and transdisciplinary research paradigm. This includes the agile adaptation of short- and medium-term research goals to requirements identified through frequent discussions with potential stakeholders.
The wearHEALTH team designs, develops and evaluates:
• Mobile and wearable technologies to support motion analysis and self-training in the context of musculoskeletal rehabilitation
• Stress and pain management apps to promote a healthy lifestyle and to support multimodal rehabilitation
Along these application scenarios the team addresses the following research lines:
• Self-configuring, ambulatory motion capturing and analysis providing valid, reliable and objective information
• Customisable, motivating user interfaces with immediate and long-term multimodal feedback
In the following, three demonstrators that the team recently presented at MEDICA 2018 are explained.
Mobile motion analysis and feedback to help patients reduce relieving postures when walking
One research focus of the wearHEALTH team is the development and evaluation of models, algorithms and systems for extracting biomechanically and medically relevant kinematic, kinetic, and spatiotemporal movement parameters from body-worn inertial measurement units (IMUs) in real-time. In order to increase the usability and reduce errors, a major goal is the development of a self-configuring system that automatically adjusts itself to the user and his context.
A concrete result of this work on mobile and wearable technologies is a magnetometer-free system for capturing the kinematic and spatiotemporal parameters of the lower body with seven IMUs. This system was already evaluated in studies with young, healthy adults concerning validity, test-retest reliability, and long-term stability during walking and other static and dynamic sport and physiotherapy specific movements. It is currently being evaluated with hip and knee arthroplasty patients.
Since 2017, the wearHEALTH team has built upon this capturing technology and has developed a mobile gait analysis and feedback system to support musculoskeletal rehabilitation. This work is performed in co-operation with the Institute of Biomechanics at the Lindenplatz Rehabilitation Clinic. The system targets people who suffer from arthrosis, for example, and who receive a new hip joint as a result. These have usually developed and internalised a relieving posture over many years. After the operation, the pain is gone, but the posture remains. The ‘normal’ way of walking has to be learned in rehabilitation and beyond.
The gait analysis and feedback system determines the user’s movement pattern to analyse whether there are deviations or individual peculiarities in the gait. The user receives guidance and immediate feedback via sound and vibrations, from which he can become aware of his gait pattern. The long-term goal is to develop a fully wearable technologies system that allows patients to continue training at home even after rehab. But it is not just the patient who receives feedback from these wearable technologies; physiotherapists and physicians can also see the data directly on a screen in the form of an animated 3D bone model and diagrams that make special features in the gait easily visible. This also allows for an objective documentation of therapy progress.
The technology is not only interesting for orthopaedic rehabilitation, as patients after a stroke could also practice with it. In addition, the application is interesting for various types of sports, for example to study or optimise movement sequences.
Gamified stress and pain management apps
A further product of the wearHEALTH team’s research is the mobile application (app) ‘Stress-Mentor’. This supports users in establishing and maintaining health-conscious behaviours and dealing with stress. For this purpose, the app makes use of evidence-based behaviour change techniques, such as self-monitoring through a diary. Each day, the user can record various stress-relevant factors such as sleep, diet, physical activity, emotional state, and perception of daily uplifts and hassles. Using scales, users can quickly assess how stressful their day was or the positive experiences they had. It takes about a minute to record such information. ‘Stress-Mentor’ also supports the learning of stress-coping methods. It offers a series of exercises, which last between five and 45 minutes, and can be individually integrated into daily routine. These exercises include, amongst others, meditation, time management, movement and stretching exercises.
Although there are many effective relaxation methods, most people have little time for them in everyday life. As such, ‘Stress-Mentor’ is designed to playfully increase motivation through ‘gamification’. One such gamification element is a little bird-like mythical creature, the Rhineland-Palatinate Elwetritsch, which the user has to look after by carrying out at least one exercise every day. Up to three exercises a day are possible. The wearHEALTH team also works on the integration of wearable technologies to provide biofeedback for supporting relaxation exercises, such as deep abdominal breathing. User feedback from longitudinal field studies was already included for improving the app. ‘Stress-Mentor’ is planned to be available for free for Android devices by the end of 2019.
Since 2017, ‘Stress-Mentor’, which was developed for the purpose of primary prevention, has been further developed for the accompanying use during rehabilitation for chronic pain patients, in co-operation with the University Hospital Halle (Saale). The resulting app is called ‘Pain-Mentor’. For this, the diary was extended with pain-specific parameters, such as pain intensity, and pain-specific daily tasks were added, such as developing a plan for setbacks or planning social support.
In a recent expert evaluation, health professionals approved the concept and content of ‘Pain-Mentor’, namely a combination of pain and stress management techniques, behaviour change techniques, and gamification. Moreover, the experts consented that the use of gamification in health apps can positively influence patients’ motivation and engagement and, thus, has the potential to promote the learning of pain management techniques and support sustainable behavioural changes.
Control with your feet – a computer game to help prevent thrombosis
Thrombosis is the third most common cardiovascular disease after heart attacks and strokes. The risk group mainly includes elderly people, but also patients who are bedridden due to an illness or have undergone major surgery. In order to prevent thrombosis, targeted movement exercises such as the rocker foot, also known as the muscle vein pump, help. To perform this exercise, first, the feet are stretched far forward and then pulled as far as possible towards the shin. This movement should be repeated with both feet as often and regularly as possible. This exercise, however, is very monotonous and tiring, so patients are usually not very motivated. Studies have shown that about 65% of patients do not do such exercises, or that they do them only partially.
This is where the computer game ‘jumpBALL’ comes in. It was developed by the wearHEALTH team in co-operation with medical doctors from the Westpfalz-Klinikum Kaiserslautern. In the game, a water ball jumps on platforms on which various items such as coins, diamonds, stars or monsters are located. If the ball hits any of the first three items, the player receives bonus points. If the ball lands on a monster, points are deducted.
The particularity about ‘jumpBALL’ is that the player controls the game with the movements of their feet. For capturing these, two IMUs are used. While playing, the user performs the muscle vein pump. In this context, experts speak of ‘exergaming’.
Consisting of two wireless IMUs and a mobile device, ‘jumpBALL’ can be easily used in different contexts (e.g. at home or in a hospital) and postures (e.g. sitting or lying). It supports personalised ranges of motion and is flexible concerning the sensor positioning, i.e. the IMUs can be attached to different parts of the lower or upper extremities to motivate respective bend-stretch-exercises.
In an experimental study with young, healthy adults, ‘jumpBALL’ motivated a higher number of voluntary repetitions and a longer training duration compared to a control version of the app in the form of a pure repetition counter. Moreover, another usability study with healthy older adults attested excellent usability and a high intention to use this technology.
Initially aimed at elderly people or patients for thrombosis prophylaxis, due to its flexible setup and configuration, ‘jumpBALL’ is currently being evaluated in the context of intensive care patients.
With fresh and positive feedback from MEDICA 2018, the leading international trade fair in the medical sector, the wearHEALTH team is currently looking for possibilities and partners to turn their existing research results into actual products in the health market. Moreover, the team is interested in continuative research and development in the following areas:
• Self-configuring, lightweight systems for mobile motion, load and strain analysis in daily life and work environments
• Multimodal guidance and biofeedback mechanisms for effectively supporting motor learning (e.g. gait retraining)
• Exploiting mobile motion analysis for human-robot-collaboration (including active support systems such as exoskeletons)
• Further development and effectiveness evaluation of Pain-Mentor with clinical partners
Scientific references concerning the mentioned research and mobile and development activities can be found at https://agw.cs.uni-kl.de/en/publications/