A primary exploration of assistive devices' design by using QFD-the electric stander for CP children as example

摘要

This study chose the standing designed for the children with cerebral palsy as the target, and invited 21 experts in the field of rehabilitation at Tainan City Assistive Device Resource Center and Chimei Hospital, as well as eight researchers to participate in this research. Data was collected from observation and interviews. Then, the Matrix of House of Quality of QFD was used to analyse, compare, and integrate the demands from medical institutions, rehabilitation centers, production units and users. The design guidelines of the standing frame are as follows: (1) Operability: the related accessories of the standing frame need to be simple and convenient for operation and adjustment with high intuitiveness; (2) Stability: when using the electric pushrod for structural design, attention needs to be paid to the tolerances of the fit between the base size and associated movable parts; (3) Economy: the compatibility of the parts needs to be considered when improving the design to enhance the operability and stability of the standing frame, in order to lower the production cost. Then bring in the industrial design method and coordinate the numerous interacting factors and requirements to develop a standing frame of a brand new concept the rigorous development conditions. The standing frame has the following characteristics: (1) horizontal lifting system: with the electric pushrod equipped with a parallel four-bar linkage and a X-type lifting structure, the standing frame under the horizontal status can be adjusted upwards and downwards by 20 cm to match up with a child patient's figure, enabling a child patient to get on and off the standing frame conveniently and easily, reducing the base packaging material and lowering the transportation cost; (2) modularized frame: with the modularized frame design characteristic of the sharing of more than 80% of the parts, it is scalable from a small size to large sizes according to the increase of a child's height; moreover, three kinds of standing posture positions of "lean back", "stand upright" and "bend over" can be covered with a single frame equipped with different back plates; eventually, a total of five styles of standing frame products can be developed-namely, the "stand upright-lean back" style, "stand upright-bend over" style, large-size, medium-size and small-size, thus able to reduce the number of replacing and purchasing the standing frame and significantly decreasing approximately 70% of the economic burden; (3) electric tilt angle adjustment: with the electric pushrod as the power source of the angle adjustment and equipped with an angle gauge, the standing frame can be adjusted from the upright status of infinite section angle to the horizontal status. Its effort-saving operation is able to reduce the workload of a rehabilitation therapist; and the angle adjustment can enhance the rehabilitation effectiveness with the practical actions. It is expected that the research results may help to build a development model for assistive devices and enhance the R&D standard of standers in Taiwan.