Design of a multipurpose agricultural vehicle and attachments for developing countries
Abstract
Many places in the developing world, particularly in Sub-Saharan Africa (SSA), lack affordable Intermediate Means of Transport (IMTs) and agricultural machinery. Cameroon, located in Central Africa, has only 19 motor vehicles per 1000 people. Available transportation options are often unreliable, have a small load capacity, or are expensive to purchase and maintain. SSA lags behind other developing regions in the use of tractors, a representative indicator of agricultural mechanization. The absence of appropriate agricultural mechanization limits productivity, the income of individual farmers, and economic growth.
A Practical Utility Platform (PUP) was developed by Purdue University in partnership with the African Centre for Renewable Energy and Sustainable Technology (ACREST), a local Non-Governmental Organization (NGO) in Bangang, Cameroon. The practical and simple vehicle is designed to haul 900 kg loads, be a platform to power auxiliary equipment, and pull ground engaging implements. After several design iterations, a vehicle design was developed that is functional, affordable, easy to manufacture, and adaptable for use in a variety of applications. In addition to the vehicle, a simple maize grinder, two-row planter, 3-point hitch caddy, and water pump were designed and tested with the PUP.
The PUP is constructed using locally available parts and materials and can be manufactured on site, lowering the costs, improving sustainability, and increasing local employment. The frame is made entirely of commonly available angle iron. The drive line uses a recycled transmission, drive shaft, and rear axle from RWD vehicles, which are plentiful in Cameroon. A simple belt and pulley reduction and clutch combination connects a 5-9 kW engine to the transmission. The single front wheel uses a front strut from a car while the rear suspension is comprised of coil springs and shocks. The implements and attachments use only basic parts and materials that can be obtained in Cameroon, like angle iron, sheet metal, and wood.
As a vehicle for transportation, the PUP has successfully completed testing both in the U.S. and Cameroon. One prototype was driven over 100 km through mud trails while carrying a 400 kg load and two people. Another diesel power PUP prototype was driven a total distance of 100 km during endurance and fuel mileage testing with loads of 70 kg, 500 kg, and 900 kg. The respective fuel economies at these loads were 26, 23, and 18 km/l (62, 53, and 41 miles/gal). Ground engagement capabilities were tested with a 3-point hitch caddy and standard cultivator, a disc plow, and a two-row planter. Several power-take-off (PTO) attachments were also tested, including a water pump and a maize grinder. Fabricating and testing multiple PUP prototypes and implements have demonstrated the resilience of this locally sustainable vehicle and platform.
