A tangible user interface-based application utilizing 3D-printed manipulatives for teaching tactual shape perception and spatial awareness sub-concepts to visually impaired children

A novel tangible user interface (TUI) based solution for teaching and reinforcing tactual shape perception and spatial awareness sub-concepts in small-scale space to visually impaired (VI) children is presented. The solution utilizes a computer vision-based system to track tagged 3D printed geometric shapes which can be manipulated by the child and provides feedback via an audio interface. The aim is to create an engaging, accessible system which mitigates the demands on the time, efforts and financial resources of the teacher/caregiver and allows a child to learn and review these concepts autonomously at his/her own pace. 3D printing has been utilized for generating the tangible tokens and off-the-shelf components have been used for setting up the TUI in order to make the system low-cost, customizable, easily reproducible and do-it-yourself. The evaluation of the system with teachers of VI children has not only validated its potential and affirmed the need for and the willingness of the teachers to adopt such assistive solutions but has also provided some invaluable insights which would be a useful resource for other researchers interested in building similar applications. The system would be extended in the future to allow teachers/caregivers to create custom shapes and to teach other essential concepts such as object sequencing and texture recognition.