Testing of a soft exoskeleton during locomotion tasks related to daily-life; XoSoft Gamma-prototype testing

Various types of exoskeletons were developed in the last decade to assist
people with mobility impairments. Most of the existing exoskeletons have a
rigid structure, heavy weight and a bulky design, which limits the use during
activities of daily living and in the home environment. Therefore, a new
project called XoSoft was conducted, to develop a soft lower-limb exoskeleton
to assist people with mobility problems. XoSoft aims for a flexible and
lightweight structure requiring low power consumption

The primary objective of this proof of concept study is to test the feasibility
of using the gamma-prototype of the lower limb exoskeleton XoSoft during
locomotion-tasks related to daily life in stroke and iSCI patients in a
controlled environment.

The feasibility will be studied by objective evaluation with focus on the
quality of the data and the stability of the XoSoft system.

The secondary objective of this proof of concept study is to test the usability
of the gamma-prototype of the lower limb exoskeleton XoSoft during
locomotion-tasks related to daily life in stroke and iSCI patients in a
controlled environment.

The usability will be studied by subjective evaluation with focus on the
user-opinion.

The feasibility and usability are evaluated by comparing results of the system
in Active (wearing the prototype while the system is activated) and InActive
(wearing the prototype while the system is inactive) state with the locomotion
pattern of the subject without wearing the XoSoft-system

The pilot study is planned as an open, randomized proof of concept study.

Locomotion tasks related to daily life and questionnaires related to wearing
the device will be performed in a controlled environment in two conditions:
1. While wearing the prototype and the system is activated (Active prototype)
2. While wearing the prototype and the system is in inactive state (InActive
prototype)

The order in which both conditions will tested will be randomized.

In a previous visit the locomotion pattern without wearing the system will be
measured

Subjects will be measured while wearing the prototype and the system is
activated (Active prototype) and while wearing the prototype and the system is
in inactive state (InActive prototype). The order will be randomized. In the
Active status the Gamma-prototype can provide support to the lower limb(s). The
system can support a total of three joints (hip, knee and ankle) per side in
both directions (flexion/extension), in any combination.

Subjects will perform locomotion-tasks related to daily life. This includes
sit-to-stand/stand-to-sit, walking in straight line, turning and walking
curves, tested using the 10m walking test, L-test and 8-figure walk test.
Furthermore, a daily-life task in a living-room like environment will be
performed.

In a previous visit the 10m walking test, L-test and 8-figure walk test will be
performed without wearing the system. Wearable sensors will be used to measure
the locomotion pattern without wearing the device.

Three visits are planned; 1 to fit and adapt the textile garment, 1 to attach
all the hardware modules to the garment and 1 to perform the measurements with
the Active and InActive prototype.

There is a risk of losing balance or falling, and subjects might get tired
during the measurements. Furthermore, skin irritations or pressure points may
appear because of direct skin contact with the system

All movements conducted during the study also occur in normal daily life
(standing, sitting, walking, turning). An experienced researcher will accompany
the subject within hand-reach during all tasks and safety grips are integrated
in the system to allow the researcher to respond quickly.

Moments to rest will be included in between the measurements and the subject
can always rest anytime he/she wants.

Potential discomfort with respect to skin irritations or pressure points due to
wearing the system are minimized by tailoring the system to the individual
participant during the first two visits.

The participants of this study will not have a direct benefit. However, with
their participation they support the development of a lower limb exoskeleton
that a substantial number of adults with moderate gait impairments might
benefit from in the near future.