Motorised wheelbarrow

On Cameroon's building sites and farms, a manual wheelbarrow demands heavy, sustained effort — it tires workers fast and excludes anyone with less upper-body strength. The brief: a motorised wheelbarrow that's easy and comfortable to use across heights from 1.5 m to 1.9 m, on a tight budget, and with no 3D modelling or simulation tools available.

Purely hands-on engineering — welding, cutting and assembling the frame from measurement and iteration, with no CAD or FEA to fall back on; every decision made physically and corrected in the workshop. A three-week sourcing hunt landed a reconditioned e-scooter motor with a pre-mounted 35–40 cm wheel, ideal for the height range. When a collaborator, Badou, flagged that shorter users were poorly served and an adjustable mechanism blew the budget, the fix was to enlarge the wheel diameter — raising the whole frame just enough. A constraint became a design principle.

Completed in three weeks and validated as comfortable for men from 1.75–1.90 m and women from 1.50–1.90 m, the motor cutting operator effort and extending working time well beyond a manual barrow. The real lesson was about tool scope: a CAD-and-simulation route would have added four to six weeks here for no proportional gain. The right tool is the one the job actually needs.