A Novel stair-climbing mobile platform and its motion control system

Abstract

Independent life is one of the most significant concerns for a disabled person specially when considering their mobility requirements. Due to the availability of facilities, both indoor and outdoor, wheelchair users face many difficulties when entering a building via staircases. Particularly, in the developing world, the concern about difficulties faced by the disabled and elderly community in accessing buildings is inadequate. As a result, most of the wheelchair users are forced to stay home and it makes their lives dependent. Since many years, scientists and researchers have been working for providing effective solutions for the mobility issues of disabled community. Stair-climbing wheelchair is one of the most powerful and popular solutions which is currently in use for mobility requirements of the disabled community. But most of the existing stair-climbing wheelchair designs have a drawback of the lack of adaptability especially at the top and the bottom of the staircase As a solution, a novel stair-climbing mobile platform with improved stability and safety is presented in this thesis. In this research, the novel mobility platform has been designed referring to the standards of staircases which have been accepted worldwide. Based on those stipulated parameters, the maximum operating angle of this design is selected as forty degrees, which is the highest angle as per the standards. Based on the literature review, track based arrangement is used as the basic mechanism for the mobile platform design because of speed, grip and user comfort. By considering the main problem of the track mechanism, variable configuration of track mechanism is used for the design in order to achieve adaptable arrangement to the staircase. Also detail analysis of design safety based on different postures on staircases are discussed and basic conditions for stair-climbing operation are derived. By considering the prototype construction, a detailed description of development stages of prototype is explained based on practical approaches in order to minimize the defects in the final product. In order to validate the stable and safe operation, simulation and experimental studies have been carried out. According to proposed novel motion plans for stair-climbing operation, the simulation study illustrates that there does not exist any sudden disturbances on the user’s operating path over staircase. By following the same procedure as used in simulation study, experimental studies have been carried out by implementing motion plans for each stage of operation. Based on the results, it confirms that the operating path of the design follows a similar behaviour as discussed in the simulation study. For further justification of the safety of the design, the actual operating path is well observed by using a video tracker software. Based on the actual operating path of the design, it confirms that throughout the staircase, the design maintains a stable operating path without creating any sudden disturbances on the mobile platform. Thus, it confirms that this design can provide a comfortable operation for the user whilst maintaining stable and safe posture throughout the operation.