Experimental comfort assessment of an active exoskeleton interface

Towards Design Guidelines for Physical Interfaces on Industrial Exoskeletons: Overview on Evaluation Metrics

“…Force-Sensing Resistor). However, as found in [4], muscular movements alter the calibrated zero value. Sensors are placed between the skin and the interface itself.…”

“…There is evidence that these devices can lower risk of occupational diseases [1] by physically assisting the worker in different tasks. Exoskeleton mechanical design and actuation were object of technical and technological advancements, however this did not happen for physical interfaces [4]. Evaluation metric are divided into objective and subjective indexes, used to quantify operational capabilities of interfaces.…”

“…In [4] and [5] wearing comfort is assessed through pressure acquisition at the interfaces with the body. To record pressures, in [4], a custom sensing system is used at every attachment point. In [5], an external commercial pressure mat is used.…”

“…In the latter case, devices have to deal with healthy muscles that vary shape and stiffness during movements. In fact [4] shows evidence that pressure exerted on tissues varies with different movements, i.e. the back thigh plate recorded up to 9.5 N single-point pressure during squat and leading leg lunge movements.…”

“…Therefore, a structured set of requirements derived from the indexes that are used to evaluate physical interfaces is desiderable. Indeed technological advancements and research were mainly focused on exoskeleton actuation and mechanical design, with comparatively few advancements in attachments [4]. Having a priority ordered list of requirements based on metrics will help further technical advancements of the interfaces and ultimately promote the adoption of industrial exoskeletons.…”