Influence of brain activities on exoskeletons
According to a study, the support provided by an exoskeleton can be reduced as soon as certain thought processes occur in the human brain.
According to a study in the scientific journal "Applied Ergonomics", the assistive forces of an exoskeleton can diminish as soon as mental work is performed at the same time. In one experiment, six women and six men were required to lift a medicine ball repeatedly during two 30-minute sessions at Ohio State University. Exoskeletons were worn during one of the sessions, and the apparatus was not used during the other session.
They measured the force applied to the lower back during each session. They then asked the same participants to perform the same task, while the subjects had to perform various arithmetic tasks in their heads, such as randomly subtracting larger numbers.
Thinking processes lead to other muscle formations
In the experiment, the execution of additional mental thought processes led in each case to a reduction of the load in the lower back region. The benefits of the exoskeleton forces when lifting and lowering the ball were virtually non-existent - the participants even had to fight against the movements. Accordingly, the exoskeleton generally attempted to track the participants' movements, but changes in the brain during mental activities affected muscle recruitments. As a result, the force impacts on the lower back became even higher, which can lead to pain.
The study apparently coincides with earlier research results from MIT. During a military training course last year, test subjects were given similar tasks - with and without exoskeletons. Although the results were widely scattered, researcher William Marras of Ohio State University confirmed that the use of exoskeletons is associated with many such compromises: In addition to the placement and selection of specific tasks when using an exoskeleton, it is therefore also important to include the cognitive tasks.
Source: Heise