Design for manufacture and assembly of an automated wood cutter: Case for developing country

Wood is a renewable source of energy that is used by everyone and cutting wood is a vast problem in developing countries such as Zimbabwe where manual methods are still been mostly used. Zimbabwe has been facing electricity shortages to the extent of importing 1200 megawatts of electricity from Zambia which is almost half of its peak demand. The aim of the paper is to design an automated wood cutter for cutting wood for domestic use. The objectives were to design a wood cutter which can cut wood of diameter 100mm, to design a wood cutter with an output capacity of (850-1000) kg per hour and to come up with a 3D prototype of the wood cutter. This machine will cut wood with minimum human influence. The objectives were achieved by performing an experiment to come up with the force required to cut the 100mm diameter round-wood and the torque generated was used to design and size the components of the machine. SolidWorks 2016 was used to calculate and estimate the bearing type and life, do the deflections and stress analysis to determine the weakest point on the machine. Automation was done using the SMT Version 3.3 PLC in connection with a shoe brake to protect the machine operator making the machine safer and user friendly. The fuzzy logic controller was used to monitor moisture content of inserted wood to prevent jamming of the machine. DFMA principle was also used to optimize the machine cost without reducing the product quality.