Cross-domain safety standards for semi-autonomous powered wheelchairs: a comparative analysis and harmonisation framework

PURPOSE: Semi-autonomous powered wheelchairs combine user control with autonomous navigation and offer substantial benefits for users with vision impairments and older adults, but their safe deployment is hindered by fragmented safety standards spanning the medical device, automotive and robotics domains. No unified framework addresses their requirements. This paper determines which safety requirements for this device class are satisfied by existing standards, which are satisfied only partially, and which are absent altogether. MATERIALS AND METHODS: Twelve international standards and frameworks relevant to semi-autonomous wheelchair safety were identified through systematic domain mapping across four sectors. Seven were subjected to full comparative scoring against a 36-dimension requirement framework adapted from UNECE NATM/FRAV automated-driving requirements, using a four-level coverage scale applied independently by four raters and reconciled to consensus. RESULTS: Seven significant gaps in current standards coverage, including the absence of requirements for autonomous navigation in assistive contexts, inappropriate controllability assumptions for users with impairments, undefined shared control safety requirements, and inadequate provisions for vulnerable user populations. Four gaps are classified as critical priority and three as high priority. Root causes are identified for each gap, and bridging potential is assessed from existing standards. CONCLUSIONS: This work provides the first cross-domain gap analysis for semi-autonomous assistive mobility and establishes a foundation for the development of harmonised safety standards. The findings have immediate implications for standards bodies, manufacturers and regulators seeking to enable safe market access for this beneficial technology.