Exoskeletons and exosuits have witnessed unprecedented growth in recent years, especially in the medical and industrial sectors. In order to be successfully integrated into the current society, these devices must comply with several commercialization rules and safety standards. Due to their intrinsic coupling with human limbs, one of the main challenges is to test and prove the quality of physical interaction with humans. However, the study of physical human–exoskeleton interactions (pHEI) has been poorly addressed in the literature. Understanding and identifying the technological ways to assess pHEI is necessary for the future acceptance and large-scale use of these devices. The harmonization of these evaluation processes represents a key factor in building a still missing accepted framework to inform human–device contact safety. In this review, we identify, analyze, and discuss the metrics, testing procedures, and measurement devices used to assess pHEI in the last ten years. Furthermore, we discuss the role of pHEI in safety contact evaluation. We found a very heterogeneous panorama in terms of sensors and testing methods, which are still far from considering realistic conditions and use-cases. We identified the main gaps and drawbacks of current approaches, pointing towards a number of promising research directions. This review aspires to help the wearable robotics community find agreements on interaction quality and safety assessment testing procedures.

Effective communication is especially important in the wearable robots (WRs) community since it encloses a great variety of devices with applications in several different fields such as healthcare, medical, industrial and military. In this paper we present a Vocabulary of terms that are relevant for diverse stakeholders in the field of WRs. This Vocabulary has been developed in the context of the European COST action on Wearable Robots for Augmentation, Assistance or Substitution of Human Motor Functions. The aim of this project is to work towards the creation of a common understanding of terms and concepts among fields of expertise involved in this field. The ultimate goal is to develop a shared documentation that could serve as a reference to facilitate the use of accepted definitions in the field. The presented vocabulary was first created by including definitions discussed in different working groups composed of several experts in the field. The resulting document was then validated by presenting the definitions to the WR community through an online survey. The survey underlined the usefulness of such a tool to prevent misunderstanding when using terminology and facilitate the inclusion of terms in the documentation. The results of the survey highlight a strong agreement in terms of acceptance of the vocabulary, its usefulness, and applicability of the proposed definitions as well as an overall appreciation for its purpose and target. This work represents a pilot study providing unique material for the WR community encouraging the use of shared agreed definitions.