Determination of vibration properties of Jatropha curcas for mechanical harvesting operations.

Jatropha curcas has been considered as a potential feedstock for biodiesel production. Today, Jatropha curcas plant has been widely planted for its fruits in order to produce biodiesel. Jatropha curcas is a species of Euphorbiaceae. The plant is a perennial shrub, which can grow approximately five to eight meters in height and it can be grown anywhere and either from seed or cutting. It seems that jatropha has a great potential to replace the fuel derived from petroleum as well as oil palm. Unfortunately, the cost of jatropha production for biodiesel is still high, especially the labor costs for harvesting. Presently, jatropha fruits are mainly harvested by hand. However, this current harvesting method is costly, as the cost of labor constitutes about 80% of the total production costs. The harvesting of the jatropha fruits is a difficult process due to the ripening characteristics of the jatropha fruits. Earlier harvesting machinery has been modified for use in jatropha, but was found unsuitable. This study involves designing and developing a branch shaker harvester. The research project aimed at alleviating problem of high production cost during harvesting by finding the vibration frequency and force needed to dislodge only the ripe jatropha fruits.