Stair-climbing wheelchairs for enhanced mobility: A comprehensive review of design concepts, mechanisms, and performance

People with physical disabilities face significant mobility challenges while climbing uneven surfaces and staircases. In such cases, conventional wheelchairs fail to provide reliable, controlled mobility and meet the infrastructural and medical needs for highly developed stairclimbing wheelchairs. In this study, a review is proposed that provides a comprehensive summary of wheelchair types, developments, compares and evaluates existing stair-climbing wheelchair technologies, and highlights major design gaps, performance limitations, and future research directions. The review examines four fundamental categories of existing systems: tracked-based mechanisms, wheel-leg hybrid mechanisms, tri-wheel mechanisms, and automatic stair-climbing systems. These mechanisms are evaluated based on critical performance metrics, including safety and stability, ergonomics, ease of use, energy efficiency, load-carrying capacity, cost, effectiveness, adaptability to variable terrain, stair-climbing mobility performance, and control methodologies ranging from manual to AI-enabled modes. The key findings indicate that although significant advancements in stair-climbing wheelchairs have been made, current systems still face challenges in portability, weight, cost, and comfort, while recent trends highlight the growing adoption of lightweight materials, hybrid locomotion, and AI-based navigation frameworks. The proposed review has identified many research gaps, including insufficient user-centric design, high demand for low-cost, reliable real-world solutions, and the need for standardized safety testing methods for stair-climbing systems. Overall, this review will provide an overview of the different technologies and a comprehensive comparison, highlight the major design trade-offs, and suggest future research directions to advance the design and support designers, rehabilitation engineers, policymakers, and the mobility assistance technology research community in developing user-friendly, comfortable stair-climbing wheelchairs.