Adaptation of Malaysian palm fruit bunch harvester to Nigerian palms
In this study, a motorized oil palm fruit bunch harvester (MT) was first tested on some plantations. The palm trees and climbers on some of the plantations were characterized. A support mechanism for the harvester was designed, fabricated and tested on a plantation. This was with a view to assessing the suitability of the harvester for harvesting the average Nigerian palms. The MT was tested on Nigerian plantations for the palm trees it could reach, the average time taken to harvest a bunch and the time taken per hectare of plantation were determined. The best orientation and the cutting angle for the harvester were also determined. The exact height which the harvester could reach was also determined on each of the plantations. The harvester was later used in comparison with bamboo pole and knife (BK) method on palms of moderate height. Time study (TS) of the two methods was also carried out. The height of some randomly selected palm trees were measured and recorded. Also the weights of some climbers on the plantations were determined. The data on the characteristic features of palm trees and climbers were used to design the components of a support mechanism. The support mechanism (SP) was designed to make the harvester suitable for the taller trees. The design concept for the support mechanism is a pyramid structure. It comprises of three different segments namely: the wheels which facilitate easy movement within the plantation; the lower segment which comprises the stands and the platform upon which the operator (climber) stands; and the upper segment which comprises the chamber in which the operator stands. The support mechanism was fabricated and tested with the harvester on some plantations in comparison with existing method, namely the rope-and-knife (RK) method. The study determined the effect of some harvesting parameters on the harvesting methods. The harvesting parameters used are time to climb up the palm (TU); time to cut (TC); time to come down from the palm (TD); number of bunches harvested (NB) and total time of harvest (T). The data collected were analyzed using Statistical Analysis Software (SAS) package. The result showed that MT could harvest between the height of 2.5 m and 4.5 m of palm conveniently. The average time of harvest per tree and speed of harvest for MT and BK were 98.86 sec. and 66 bunches/h; and 166.93 sec. and 40 bunches/h, respectively. This shows that time of harvest for motorized harvester is over 60% lower, and the speed of harvest is over 50% higher than bamboo pole and knife. The time of harvest per hectare for both MT and BK are approximately 4 h/ha and 7h/ha, respectively. Statistical analysis of the effect of time of harvest on methods indicated that the effect was significant (p < 0.05). Using the support mechanism for the MT it was much easier than rope and knife. The average time of harvest, TU, TD, and TC per tree, for both SP and RK are 189.64 and 391.20; 21.28 and 151.82; 21.08 and 103.42; and 147.28 and 134, respectively. The total time of harvest for RK is over 100% more than the time of harvest for SP. The time of harvest per hectare for both SP and RK are approximately 9 h/ha and 20 h/ha, respectively. The comparison of SP and RK shows that there is a significant difference in TU, TD, NB, T, but there was no difference in TC, (p < 0.05). The study concluded that the support mechanism shows promise in enhancing the use of the motorized harvester for tall palms and hence should be adopted.