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Final Report Summary - WANDER (Wander)


Falling is the leading cause of accident-related injury among all age groups, but is particularly threatening among sufferers of conditions that affect motor control or result in sensory or cognitive impairment. Adults over the age of 65 are at great risk of serious injury during falling, and, in the event that the hip is fractured, have a 25% chance of dying from their injuries within 6-12 months of the event.
Falling can also have a profound psychological impact. Even if physical injury has not occurred, loss of confidence can reduce mobility and, as a result, lead to decreased independence in performing normal daily functions and a subsequent withdrawal from social and physical activities.
Conventional means of assisting balance, such as walkers and canes, have the shortcomings that (1) their effectiveness is dependent on the ability of the user to detect when a loss of balance has occurred, which is difficult for people with sensory impairment, and (2) these objects must be held when in use, which means that they prevent the hands from performing other tasks and that constant use may result in developing excessive reliance or maladaptation.
To develop a hands-free balance-assisting device capable of automatic detection and correction of instability, the field of wearable robotics offers potential. Robotic exoskeletons for the legs have also been suggested to support walking. However, exoskeletons are usually not targeted at balance assistance, they are noticeable as aids due to their often bulky structure, and they require attachment and alignment, which are difficult and cumbersome tasks for elderly users.

Main Project Objective

In WaNDER, researchers aim to develop novel robotic interventions that influence human walking and balance at the upper body during overground gait, instead of on the legs. In contrast to existing solutions that enclose subjects’ legs, interacting with the upper body leaves users more freedom to move, and it makes attachment simpler. To control such devices, researchers investigate cooperative mechanisms that learn and adapt to a human user, as well as sensor concepts that enable detecting falls before an impact has occurred.
A main objective of the project is a wearable solution to stabilize human bipedal gait. The idea is to provide patients with a device worn on the upper body (a backpack) that does not interfere with their gait, unless when necessary to prevent a fall. The fellow’s group has developed a balance-assisting backpack-like corset that can be quickly and easily mounted/dismounted and leaves the limbs free and uninhibited to allow comfortable movement. The key principle is to use fast-spinning wheels, so-called control moment gyroscopes (CMGs), which are also used to control attitude of space vehicles.

Work performed

Using overhead support systems, the group has conducted experiments on how assistive forces on the upper body influence gait [Awai2017], and in particular how human balance can be influenced by robotic interventions on the upper body [Fritschi2014]. The group has also used other robotic platforms to investigate learning paradigms to assist walking [Pagel2016, Koryakovskiy2017] and other rhythmic tasks [Marchal2015]. A major outcome were model-based algorithm that enable real-time and precise observation of balance with only sensors on the upper body [Paiman2016]. Such algorithms enable detection of a fall before it has occurred, such that intervention is still possible.
Simultaneously, the fellow’s research group has constructed a first prototype of a wearable backpack with gyroscopic balance assistance, and quantified its torque-generation capabilities [Lemus2017]. Within the project, also an ergonomic interface for the backpack has been designed, such that it fits a wide range of possible users.
Clinical evaluation of the wearable backpack is currently being performed in cooperation with the Rehabilitation Institute of Chicago (RIC), within the MARS3 rehabilitation engineering research center.

Expected wider impact:

WANDER directly addresses the main risk factor of falls, which is impaired balance. Many elderly citizens could benefit from easy-to-wear balance support, preventing the often devastating consequences of a fall. Based on the outcomes of this project, users will eventually receive unobtrusive devices they can wear in daily life. It will not require them to attach and align a structure on the legs like in exoskeletons, so that it can also be used by subjects with limited mobility.
Selected scientific publications

[Lemus2017] Lemus, D.; van Frankenhuyzen, J. & Vallery, H. Design and Evaluation of a Balance Assistance Control Moment Gyroscope. ASME Journal of Mechanisms and Robotics, 2017
[Berry2016] Berry, A.; Lemus, D.; Babuška, R. & Vallery, H. Directional Singularity-Robust Torque Control for Gyroscopic Actuators. IEEE/ASME Transactions on Mechatronics, IEEE, 2016, 21, 2755-2763
[Fritschi2014] Fritschi, M.; Jelinek, H.; McGloughlin, T.; Khalaf, K.; Khandoker, A. & Vallery, H. Human balance responses to perturbations in the horizontal plane Engineering in Medicine and Biology Society (EMBC), 2014 36th Annual International Conference of the IEEE, 2014, 4058-4061
[Paiman2016] Paiman, C.; Lemus, D.; Short, D. & Vallery, H. Observing the state of balance with a single upper-body sensor. Frontiers in Robotics and AI, 2016, 3
[Awai2017] Awai, L.; Franz, M.; Easthope, C. S.; Vallery, H.; Curt, A. & Bolliger, M. Preserved gait kinematics during controlled body unloading. Journal of neuroengineering and rehabilitation, 2017, 14, 25
[Shirota2017] Shirota, C.; van Asseldonk, E.; Matjačić, Z.; Vallery, H.; Barralon, P.; Maggioni, S.; Buurke, J. H. & Veneman, J. F. Robot-supported assessment of balance in standing and walking. Journal of neuroengineering and rehabilitation, 2017, 14, 80
[Marchal2015] L. Marchal-Crespo, M. Bannwart, R. Riener, and H. Vallery, “The effect of haptic guidance on learning a hybrid rhythmic-discrete motor task”, IEEE Trans Haptics, vol. 8, no. 2, pp. 222-234, 2015.
[Pagel2016] Pagel, A.; Ranzani, R.; Riener, R. & Vallery, H. Bio-Inspired Adaptive Control for Active Knee Exoprosthetics. IEEE transactions on neural systems and rehabilitation engineering, 2017
[Koryakovskiy2017] Koryakovskiy, I.; Kudruss, M.; Babuska, R.; Caarls, W.; Kirches, C.; Mombaur, K.; P.Schlöder, J. & Vallery, H.. Benchmarking model-free and model-based optimal control. Journal of Robotics and Autonomous Systems, 2017

Further information, animations, and videos on the working principle of the gyroscopic backpack are available on the website:

Contact details: Heike Vallery, 3ME, TU Delft,