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DEVELOPMENT OF A COMMON LANGUAGE TO DESIGN A TRICYCLE FOR PHYSICALLY IMPAIRED PERSONS IN DEVELOPING COUNTRIES

I. Oldenkamp Faculty of Industrial Design Engineering Technical University Delft, The Netherlands

ABSTRACT

The project Development of Tricycle Production (DTP) in developing countries was aimed at the design of tricycles that could be produced, maintained and used locally. This would contribute to the participation of disabled people in developing countries in their social and economic life. The Delft University of Technology carried out this project in close cooperation with four Asian organizations, the counterparts which already produce mobility aids. Early in the project it was understood that establishing a common design language would be vital for communication. This paper describes how this common language was established by conducting a design exercise during which a tricycle for children was made.

BACKGROUND

Of over 500 million more or less physically impaired persons today; 80% are living in developing countries. As a consequence of disease, accident or war many of these, mostly poor, people have partly or completely lost their freedom of movement, which seriously hampers their opportunities in education, (finding) work and participation in social life Many of them would be helped with appropriate means of transport, e.g. a wheelchair or a tricycle. Although many developing countries do have facilities to produce these mobility aids, the demand by far exceeds supply. Imports from abroad could contribute partly in this supply. However the problem with these imported products is that they are often too expensive and not suitable for use under the average (much worse) conditions in these countries (e.g. bad roads, dust etc.) and that there will be the problem of spare parts. It is generally recognized that continuous provision of mobility aids can, on the long term, only be guaranteed when based upon local production. A lot of work has been done already to stimulate and support local production by Ralf Hotchkiss of ATI in the USA in co-operation with several small workshops in Latin America. They designed a wheelchair, that can be produced with fairly simple tools and local materials in most developing countries. With it they published a production manual. With regard to tricycles a similar development focussed on developing countries has not yet taken place. In developing countries wheelchairs and tricycles are being produced at different scales, although small-scale production seems to be the dominant mode. CICAT (Centre of International Co-operation an Appropriate Technology acquired a grant from SHIA (Swedish Organization of Handicapped International Aids Foundation) to design a tricycle that can be produced and maintained in developing countries in co-operation with local workshops which are active in the production of mobility aids [1, 2]. This project was conducted together with FIDE (Faculty of Industrial Design Engineering) of the Technical University of Delft (The Netherlands).

OBJECTIVE

In general, when designing any product, the designer should know the user and the circumstances the product is used. This also applies to a tricycle and its production manual. In order to be able to communicate local producers of wheelchairs a first objective was to establish a common language.

APPROACH

In many developing countries local organizations are involved in the production of tricycles, wheelchairs and other equipment for the handicapped. Several of these organizations have made it clear that they are looking for technical support in the field of improvement and production of these transport means. Up to now most of CICAT's (project) activities in the field of wheelchair and tricycle production have taken place in direct contact with organizations in South and South-East Asia For practical reasons the project was focussed on cooperation with three Asian organizations described below. The choice for this being that these organizations are already producing tricycles and/or wheelchairs or other mobility equipment for the `handicapped; they are all situated in the same region and finally they are familiar with CICAT. Next to this CICAT-Transport had also informal contacts with and/or information on various other organizations (in Asia, Africa and Latin America) which might be willing and suitable to act as a counterpart at a later stage. It was decided to co-operate with: (1) Workshop for Rehabilitation and Training of the Handicapped (WORTH), Katpadi, Tamil Nadu in India (2) Sarvodaya Economic Enterprises Development services (SEEDS), Ambalangoda in Sri Lanka and (3) McKean Rehabilitation Centre (MRC), Chiang Mai in Tailand. Apart from the fact that they are located some thousands of kilometers apart in different countries, with different languages and cultures. Also working conditions and technical knowledge differed widely. As these particulars were foreseen in the planning of the DTP project, seminars were included. The objectives were threefold: 1 understand in the capabilities of the counterparts; 2 develop a common language with respect to design and to the design of aids to physically impaired people and 3 to design, together with the counterpart a tricycle that could be produced in developing countries. In all three seminars were planned: 1.Develop a common language and give insight in the design process; start of the development of a tricycle for physically impaired people. This two week seminar was held together with the department of Mechanical Engineer of the Chiang Mai University in Thailand 2. Further jointly development of design work done by the counterparts and to discuss the results of the work at the FIDE (The Netherlands) and to visit small companies which produce mobility aids. This seminar took two weeks. 3. A  three week workshop during which two distinct prototypes of a tricycle were made and tested. This workshop took place in India at WORTH.

RESULTS

The first seminar was centred around a design exercise during which a children's tricycle had to be designed. During this exercise also (morning) lectures were given by lecturers from both the Chiang Mai University and FIDE on theoretical subjects related to the construction of wheelchairs. In all six members of the counter parts participated in this seminar. The morning lectures were centered around components and related subjects, like:

frame statics- types of loads, stress and strain, strength of materials, forming and joining of steel tube and sheet metal;

steering/braking - vehicle mechanics, steering geometry, principles and construction of brakes; propulsion

principles of motion - work and energy, principles and construction of transmission, mechanisms;

user interface - ergonomics, paraplegic, polio and amputee patients, symptoms, specific problems, therapies, prevention of problems, adjustments and supports.

Design Exercise

It may sound strange to use a children's tricycle as design subject as such product is so much different from a wheelchair. The reason for not taking a tricycle for handicapped persons as the subject of study was threefold: as all participants work already in the production of tricycles, it was feared that discussions would too easily be centred around particular designs of the participants and thus hindering an open mind to the underlying principles when designing a tricycle for handicapped people. Also it would be very tempting for the participants to jump to conclusions that merely would be a choice for existing solutions decided upon in the past. (This is not to say that these solutions are without value, only that their merits should again be weighed against other solutions). The participants had to do some home work: take measures of their own child (or any other child they knew between 5-8 years of age), as it was the intention to design the tricycle for that child. The measures are indicated below:

Dimensions of children's tricycles are distinct from tricycles for (handicapped) grown-ups. Apart from the overall size, also relative dimensions are different so there is no opportunity to fall back on rules of thump. On the other hand: properties of such a children's toy resemble a tricycle for handicapped persons in that there is a seat, footrests and a handlebars, of which the relative positions have to positions are dictated by body dimensions. At first ideas had to be generated. It was demonstrated here, in the form of rough sketches, that many different sorts of tricycles are possible. After applying an evaluation with help of a first issue of a List of Requirements LoR), the best ideas were selected. These ideas were further elaborated to technical sketches with actual dimensions. Here the scale models that the counterparts had made of their child were used to position seat, pedals and handlebars correctly. (It was pointed out that children grow, so that the tricycle had to be adjustable). Calculations proved to be difficult, however with help of the staff, solutions were found to establish the dimensions of the main parts. It was demonstrated clearly that through calculation light and strong enough constructions can be made. Also during this stage constructions were optimized by comparing different solutions for various details. No time was left to build the tricycles, but the counterpart left the seminar with a complete set of technical drawings, so they could build the tricycle later. They actually did that. The conclusion is that transfer of training applied to the following aspects: Design process: identical. Techniques used for generation of ideas; discrimination of quality of solutions: identical. Information gathering and analysis: with respect to the specific body dimensions identical, however different in terms of use and production.

DISCUSSION

During the six afternoons and two days, the designs of the children's tricycle were completed. The morning lectures proved helpful in understanding the construction of tricycles, but the application of theory to actual constructions appeared to be very difficult. The design process, together with the applied techniques, was found to be a helpful tool. It was agreed to use it during further execution of this project. It was concluded that:

A new way of working was introduced to the counterparts. Their usual way of working is building a prototype directly in hardware and modify it until the result is satisfactorily. It was clearly demonstrated that by using a step by step approachstarting with sketches on paper with subsequent evaluations is a very efficient.

Using data from simple ergonomic measurements is an effective way to determine the dimensions of a tricycle.

Technological knowledge in local workshops is strong in producing complicated constructions with modest equipment. Theoretical knowledge is limited, resulting in poorly performing designs.

Lots of knowledge is present locally in universities. This knowledge is difficult to come by for the counterparts as there is no tradition to exchange information.

Ergonomic data is not readily available in workshops. It was taught that with relatively simple rules and measurements main dimensions of a tricycle can be obtained .

A manual should appeal to the technical knowledge present and give information in a pictural way rather then text and formulae.

The design process presented during this seminar was found to be a good tool for both designing and communicating.

References:

1. Development of Tricycle Production in Developing Countries, 1991, Centre for International Co-operation and Appropriate Technology

2. Boeijen, A.G.C. van Development of Tricycle Production in Developing Countries, RESNA '96

I. Oldenkamp Faculty of Industrial Design Engineering Delft University of Technology Jaffalaan 9, 2628 BX Delft, The Netherlands Phone : +31 15 278 3088 Fax : +31 15 278 7179 Email: I.Oldenkamp@io.tudelft.nl