Workbike research
news comment makers operators resources research free ads	Tricycle Wheelchairs for Sri Lanka Through its projects world-wide, Motivation has seen evidence of a growing need for tricycle type wheelchairs in both urban and rural terrains. Our experience in Cambodia and Afghanistan, where we developed a tricycle drive attachment for our three wheeled wheelchairs, has shown that tricycles offer unique advantages with increased load carrying capacity and greater distance travelled for less effort expended. Tricycle wheelchairs, which are three wheeled and propelled by hand using a cycle drive unit connected to the front or to one side wheel, are widely used by the disabled community of Sri Lanka. Many users adapt them to become a mobile place of work and income generation, for example, selling lottery tickets, newspapers or trinkets. Tricycle wheelchairs are the most visible form of mobility for the disabled community of Sri Lanka and are accepted within society. The "Rehab Lanka Tricycle" or "TWSL" designed by Motivation Having decided on the aims and methodology to be used, the basic design was taken and revamped. A new sub-frame system was designed which gave increased strength and durability, yet also added controlled flexion in the frame for smoother riding. Ergonomic factors were used in positioning the seat with relation to the drive unit, the size and shape of the seat and backrest. Following that, adjustable foot plates and seat positions were incorporated into the seat module. The wheel axle and wheel hub were redesigned adding strength, whilst allowing better access to the rear wheels for both use and maintenance. Due to the dehydrating climate in Sri Lanka an easy accessed water bottle carrier was incorporated as part of the frame. The original "under seat box carrier" was retained, but a front wheel load carrier was added, which not only increase load carrying capacity also reinforces and strengthens the front wheel forks. Material and production costs were constantly being evaluated and kept to a minimum without compromising strength or durability. This design was carefully kept simple to produce, using basic materials and tools. Thus allowing easy replication and production by other "small rural" workshops with the minimum of training and tool changes. Flexible, yet strong frame design allows "shock absorption" on rough roads and curbs, etc. Easy access to rear wheels for both , "hand propulsion" and maintenance Standard right hand driving wheel Full 430mm seat depth with adjustable seat positioning and fully adjustable foot plate heights Lift-up armrest for easy access Lockable under seat box carrier and front wheel load carrier Easy access water bottle carrier The "Delft" Tricycle - Modified by Motivation for Sri Lanka This design was taken from a design used in Africa. Modifications needed to be made however, due to materials supply and ergonomic factors. Many materials in the original design are not available at low cost in Sri Lanka, and general physical size of the people of Sri Lanka necessitated the basic modification of the design. However, it is generally easy to build and copy and makes a good comparison for the disabled people of Sri Lanka to make their own choice in which type they want to use. Trials of the designs are carried out by local disabled people, as well as an active western wheelchair user who works as a trainer and out-reach educator. The feedback from these durability and user trials is being used to help assess the designs prior to full production in March 2000. Motivation Phone: +44 1275 46 40 12 Email: motivation@motivation.org.uk www.motivation.org.uk back to the index