AfriCart – a handcart for Africa

ED302 – design & technology

09.0 Testing & Evaluation

Testing

outer_push_africart

A. Child pushing the cart

This is a good position for pushing the cart on level ground or downhill. Jasmine, (1.58m), tried the AfriCart out on the University Rugby field – as you can see the adult setting means the load bed rides at quite an angle which could be good on rough ground, however I feel that there would be to much strength required from a child/small woman to keep the handle “down” and therefore to control the cart comfortably. Therefore the child setting should be used.

Inner_push_africart

B. Child pulling the cart

This is a good position for level ground and for going uphill. Jasmine could lean her weight into the handle and she was therefore able to push the cart uphill easier and in a more controlled way than A. By putting the rear legs up she could also use them to help the load from moving backwards.

Final_africart_fatboy

C. Adult pushing

As you can see the child setting is too low for a tall adult – the load would keep shifting forward and the cart’s front would keep digging in.

Evaluation

The design brief & specification for this project were the direct products of targeted research and development, and so I felt that I genuinely understood the need for my product and that I addressed the gaps in my knowledge logically and fruitfully. The research, and interviews, that I undertook really helped me define and refine both the problem and the solution and by pursuing a mainly lateral line of research I built a cumulative body of knowledge that enhanced my subject knowledge of both carpentry, sustainability and gender issues in SSA.

The nature of the materials used, bicycle wheels, partly defined the nature of the solution. Each wheel had a short axle that necessitated being supported on both sides. Duplicate this on both sides of the cart – add a few cross members and you have the basis of a design, form following function. Because my target users were children and women (who tend to be smaller than their European counterparts) then the size of the cart needed to be smaller than their male counterparts.

The average load bed with of a Pioneers’ hand cart was 48″ and so I decided that the width of my AfriCart should be half that: 24″. Although the AfriCart cannot be tested in situ (sub-Saharan Africa) I have been testing it in the university environment: up and down steps; grassed slopes and on the level with both adults and children.

To see how it compares to the original specification:

  • Light – Made from the lightest possible materials I feel I have achieved the best combination of weight and strength.
  • Strong – Ditto.
  • Max. load capacity: approx. 100-150kg (5-7 x normal carrying capacity) – Tested with a load of 80kgs, however not tested with this load on rough ground
  • Mobile – Although difficult the to navigate through narrow alleys it performs well in the open spaces it was designed for.
  • Relatively cheap to produce – In the UK it can be produced for under 15 USD, however, even though the wheels may have to be bought I stillfeel it could be produced cheaply in Sub-Saharan Africa.
  • Easy to construct – With basic tools and skills a rural carpenter should have no problem constructing this cart.
  • Easy to repair – Ditto.
  • Made using natural and recycled materials – This condition can be satisfied in SSA.
  • Utilising 26 – 29” bicycle wheels (front & rear) – Currently using 26″ wheels, only the position of the dowels may need to be altered to accomodate 29″ wheels.
  • Made and repaired using basic hand tools –This condition can be satisfied in SSA.
  • No metal fastenings other than the bicycle spindle retaining nuts – Completely satisfied.

In summary I feel I have built a good practical solution to the problem I was presented with and I genuinely now feel confident in handling all types of wood and wood working tools including the industrial fixed tools in the workshop such as the planer/thicknesser and the circular saw.

If this was a real world product, once complete and handed over to the end user, I would expect them to chemically treat the wood with creosote or paint & decorate it as shown in 10.0 Further Development – Product enhancement.

Achievements

I am actually quite proud of my design and especially the research that led me to it. I feel that after a few hiccups in the initial design process that I quickly and logically built the cart. There were a few design problems that had to be addressed near completion however, due to the complete knock-down design, these were swiftly and painlessly implimented (Eg: rear legs).

I realise that my mortice and tenon joints do leave alot to be desired however I am very proud of the fact the the complete cart can be built without the use of a single nail. I thought the use of wooden pins was great as it allowed me to assemble and dis-assemble the complete cart quickly and easily numerous times – this will be especially helpfull to allow for bush repairs and modifications.

I also feel that I have learned a great deal about the teaching of D&T and have therefore made a conscious decision to concentrate alot more on the process rather than just on the end product. I have also learned more about the imporatnce of research and how, just one short conversation with an expert, can set you on the correct path.

Written by Mr. Elphick

February 16, 2009 at 12:58 pm

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