Design for Multi-lifecycle: A sustainable design concept applied to an agroindustrial development project

Sustainability of technologies has been the central focus of many international debates, seminars and forums. The need for sustainable technologies in the developing countries is particularly critical in view of their limited financial and techno-capability. Designing for sustainability requires the consideration of a number of factors such as how to minimize total lifecycle cost, techno-capability of the local technicians in maintaining and improving the technology, minimizing environmental cost of using the technology, end-of-life management of the technology and several other factors that are relevant to the location where the technology will be deployed. In this design and development project, a shelling machine was designed for multi-lifecycle. The essence of this design paradigm was to facilitate unlimited use and reuse of this technology. The design concept is based on an integrated concept of design for modularity, disassembly, maintainability and remanufacturing. The machine can be used to shell/thresh various types of farm produce such as rice, sorghum, cowpea and rye by changing the concave and the cylinder. The configuration of the machine enables access to most of the component parts without changing the tools needed for disassembly because the same type of fasteners was used. Furthermore, the functional units (the shelling unit, the separation unit and the grading unit) were assembled into modules such that only the faulty part needs to be replaced when necessary. The design is so simplified that the operator can make the changes for different uses without any difficulty. The machine has been successfully tested on corn, peanuts and other agricultural produce. The modularity of the functional unit facilitates the multi-lifecycle use of machine and/or its component parts. The uniformity of the liaisons and simplification of the configuration will reduce both the disassembly times and maintenance cost. By this unlimited usability/reusability of the machine, the material requirements for producing brand new machines are conserved, environmental emissions that would be associated with the manufacture; transportation and disposal of the machines are eliminated while the capital requirements by farmers for machinery replacement are minimized. Consequently, the total lifecycle cost is minimized while the eco-efficiency is maximized.