Engineers building an all-road wheelchair made from carbon fibre have given themselves a mountain to climb in the form of Mount Kilimanjaro. Five Airbus engineers, who are members of the Spanish Group of the Institution of Mechanical Engineers (IMechE), will accompany a Paralympic athlete using the wheelchair on a journey to the Tanzanian mountain in September.
Airbus head of supply chain quality procurement Manuel Santaolalla told The Engineer that using carbon fibre will make the design as light as possible but still capable of handling the rugged terrain. At just 15kg, it will be 50% lighter than all-road wheelchairs on the market.
The team has finished a prototype, which will be tested on mountains outside Madrid.
“From a design point of view it is accurate, but from a manufacturing point of view it will bear no resemblance to the one that will go up, because basically we have riveted most of the components rather than manufacturing in one shot in composites,” Santaolalla said.
“We need to be able to move the seat, the chest plate and the leg supports, as well as other areas, so that we can implement modifications on the final design, which will be a one shot that will eliminate a lot of the weight.”
The wheelchair has two wheels at the front and one at the back to provide stability, while hand levers provide power.
“We use a similar mechanism to what we use on a normal bicycle, except that they are shaped for the hands and they have a pinion and a chain that go to the back wheel,” Santaolalla said.
The steering mechanism has been designed to lock in place so that the athlete can then use the hand levers.
“The difficulty with these is you cannot pedal at the same time as you steer, as with a normal bicycle,” Santaolalla added.
The chest plate allows the user to lean forward to hold the hand pedals.
It incorporates foam for comfort and a liquid gel that also provides heat, as cold is an issue on Kilimanjaro, which is almost 6,000m above sea level.
Excluding the standard-type wheels, the wheelchair will consist of 80–90 per cent carbon fibre, Santaolalla said.
The Airbus plant at Illescas in Spain, which manufactures carbon fibre aeronautical components, has contributed materials and engineering knowhow to the project.
Engineering company Altran is also supporting the expedition and helped develop the wheelchair.
“They have a background in automotive and gearboxes and drive mechanisms, so I felt that would be perfect,” Santaolalla said.
The expedition, which will follow the Marangu route to Kilimanjaro, will take place from 3–15 September.
It will consist of the athlete, who has not yet been chosen, along with three doctors from the Hospital Clínico San Carlos in Madrid, five Airbus engineers, a member of Altran and two guides.
Free-to-use designs and instructions on how to build the wheelchair will be put on the Airbus and IMechE websites.
“Groundbreaking technology has come together with humanitarian work for this challenge and illustrates the Institution’s commitment to improving the world through engineering,” Santaolalla said
Glynn Garlick|the engineer