So that we can offer what we promise, we test what is possible.
The following results were produced at ETH Zurich.
To prove our developments, we meticulously check our results. The BionicBack was tested by us in the test laboratory at ETH Zurich. Thanks to the measurement technology used, we can reliably prove the relief in a muscle-specific manner. The aim of our investigations is to measure the fatigue and strain in the affected muscles. Our holistic approach is not only aimed at maximizing support, but also focuses on optimally coordinating all factors involved.
The way in which exoskeletons work is focused on influencing biomechanical parameters. These can be measured, for example, using so-called surface electromyography.
In surface electromyography, adhesive electrodes reflect muscle activity in the form of electrical potential. This means that muscle exertion and fatigue parameters can be read out later in the analysis.
To test the BionicBack, each test person was equipped with electrodes on the muscles that are centrally involved in lifting: muscles for extending the spine in the lower back, muscles for stretching the hips in the buttocks and back of the thighs and muscles for stabilizing the trunk in the abdomen were measured.
The benefits of the system can be seen in the comparison of the strain and fatigue parameters: Without support vs. with support from the BionicBack.
#Measuring method sEMG
Study design: Dr. Felix Thomas
In order to optimally represent the application in everyday work, each test subject completed dynamic lifting movements as well as holding tasks in a deep forced posture. Each task was performed with a 20kg test weight to simulate the average target application of manual handling.
The static holding task was also carried out up to the maximum holding time in order to measure the holding power with and without support.
20kg as an everyday test weight
If the weight to be lifted is smaller, the relief values are higher.
To measure the relief provided by the BionicBack, the activity of the muscles that are mainly involved in lifting movements in the body were measured in the laboratory. These are located on the back of the legs, the buttocks, along the spine in the back and on the sides of the stomach. (Hip extensors, back extensors and pelvic stabilizers) By using the BionicBack, it was possible to reduce muscle activity by up to 24% and muscle fatigue by up to 86%.
Static holding task
In the other test run, a static holding task was carried out and muscle activity was also measured. Each subject carried out the task for as long as they could. For comparison, once with and once without BionicBack. Significant muscle relief in the back extensor of up to 24% at times could be measured. Viewed over the entire exercise period, the use of the BionicBack can reduce muscle activity in the back extensor by 6%, in the back of the legs by 13%, in the buttocks by 11% and in the lateral abdominal muscles by 22%. However, it can be observed that the relief is concentrated on different parts of the body at different times of the load. Especially in the last 30s there is an increased relief of the back extensors, up to 24% on average. That means, especially at critical times when the back extensor muscles works at the load limit, the BionicBack takes on more and more of a support task for the wearer.
Dynamic lifting task
In one test run, the muscle activity was measured during lifting movements with a 20 kg weight. The movements were carried out in a standardized way with and without the support of the BionicBack and the results were compared. Averaged over the five test subjects, the result was a relief in the form of lower muscle activity of approx. 9% in the back extensor, 11% in the back of the legs and 36% in the abdominal muscle, while the gluteal muscle was relieved by 4.5%.
Increased holding times thanks to BionicBack
The supportive effect is not only evident in the reduced muscle activity, but above all in the increased holding time. Each subject was able to hold the holding task significantly longer if he used a BionicBack, on average by 55% longer.
Significant reduction in signs of fatigue through BionicBack
Electromyography can measure not only muscle exertion, but also muscle fatigue over time. Put simply, a tired muscle can be controlled neuronally with less high frequency over time - the decline of the signal frequency can be modeled in a (computer) analysis. This analysis shows that all measured muscles show significantly reduced signs of fatigue when they are supported by the BionicBack. With BionicBack, the back extensor tires averaged 86% less, the back of the leg by 50%, the gluteal muscle by 76% and the lateral abdominal muscle by 57%.
Do exoskeletons therefore contribute to occupational safety ?
With the help of these results, our goal - #SupportToWear - can be proven. The results are scientifically valid and allow a good insight into how the BionicBack works.
Much more important, however, is that these results can be achieved without affecting usability. And that, in combination with the small system structure, the low weight and the variable functionality, makes it unbeatable. As current studies confirm, exoskeletons can only work if they are used for a long time without obstructing factors such as large structures or a high system weight.
"That we can provide such tremendous data makes us particularly proud and encourages us in our "just do it"-culture."
CEO & FOUNDER
Current studies make it clear how important a high level of user acceptance really is when using exoskeletons. In one study, the scientists say that prevention is only possible if user acceptance of exoskeletons improves in the future. For subjects with back problems, the restrictions caused by the bulky system were very acceptable, but for subjects without back problems, the benefits could not make up for the limitations. (3)
3 Kozinc, Ziga; Babic`, Jan; Šarabon, Nejc (2020): Comparison of Subjective Responses of Low Back Pain Patients and Asymptomatic Controls to Use of Spinal Exoskeleton during Simple Load Lifting Tasks: A Pilot Study. In: International journal of environmental research and public health 18 (1). DOI: https://doi.org/10.3390/ijerph18010161 .