Development of a high clearance android-controlled inter-row weeder for rice intensification system

• Main Author: Suleiman, Samaila
• Format: Thesis
• Language: English
• Published: 2017
• Online Access: http://psasir.upm.edu.my/id/eprint/70192/1/FK%202017%20112%20-%20IR.pdf; http://psasir.upm.edu.my/id/eprint/70192/

Research was carried out to develop a high clearance inter-row weeder machine with Android control system, to address the challenge of high crop damage associated existing inter-row weeding machines due to low ground clearance under the system of rice intensification. This research was carried out in three main stages namely: Preliminary studies to evaluation of some existing inter-row weeders, Development of a prototype high clearance Android controlled weeding machine and Evaluation of the prototype machine. Four existing mechanical inter-row weeding machines with different design configurations used by farmers in Tanjung Karang Malaysia under system of rice intensification were selected and evaluated in terms of crop damage factor at forty days after transplanting. The result revealed that none of the four existing machines could weed up to forty days after transplanting (40DAT) due high crop damage as a result of inadequate machine ground clearance. The frequency of weeding cycles was found to increase rice yield, with 13.1tons/ha for the three cycle weeded plots, whereas a maximum of only 9 tons/ha was recorded with two cycle weeded plots. A prototype hydraulic powered inter-row weeder having 60cm ground with Android control was developed to weed in paddy field at different stages of paddy heights under the system of rice intensification. The machine was built on Kubota S125 engine as its prime mover. A 120cm diameter cage wheel designed with lugs to aid traction, adequate adjustable track width of 25cm to 30cm to accommodate variation in inter-row distance to reduce crop damage. Other components of the machine are the main frame attached to the prime mover; five row rotary weeding assembly units with hydraulic depth control attached to the main frame. A 12V 3-2 way solenoid directional control valves mounted on MMC-01-4 Manifold block regulate flow to and out of actuators. An android application was developed to automate the prototype machine via Android phone Bluetooth within 100m operating radius. A 2.4G wireless video module on the machines as the mobile node transmits real time video signal, thus enabling tele-operation of the machine via android phone. The prototype machine was evaluated to establish its performance parameters at block D, Sawah Sempandan, Tanjung Karang, Selangor Malaysia. The experiment was a Split Plot Design experiment with five (5) main and sub-plots were studied. The plot size of 2.3m x 16.5m (37.95m2) each was used for the evaluation. The main plots are two levels of plant spacing of 30cm x 21cm and 30cm x 18cm, Number of weeding cycles (5 levels), two level of rotor 500 RPM & 600 RPM, Seed rate (two levels). Mechanical weeding was carried out using the high clearance inter-row weeder at 10 days interval as recommended by the system of rice intensification (SRI). Data collected on machine weeding performance were subjected to ANOVA and DUNCAN test analysis using the SAS (version 9.3) statistical software. Result showed that the prototype machine was able to weed up to fifty days after transplanting with low percentage of crop damage of 2.54%. The mean comparison of rice vegetative height were 61.90cm and 62.18cm while yield were 7.09tons/ha and 7.01tons/ha respectively for the fourth and fifth weeding cycles. These results suggest no significant difference between the fourth and fifth weeding cycles, thus implying weeding can be stopped at the fourth cycle without significant loss in yield. The seed rate and hill spacing were also observed to significantly influence the yield positively. The single seedling plots yielded an average of 9tons/ha both for four and five weeding cycles, while the 2-3 seedling per hill plots yielded an average 5.5 tons/ha to 6 tons/ha for same level of weeding. The analysis of machine rotor rpm was shown to be significant on weeding efficiency and fuel consumption at P ≤ 0.05 level, having 92.93% and 1.29 lit/hr respectively at 600 rpm. However, a similar trend was observed in the percentage of crop damage with increase in rotor speed. The android control user interface design implementation among three groups of planters (A) 18-25 years, (B) 26-32 years and (C) above 32 years, revealed no significant different in the scores of the three age groups that participated in the evaluation. This suggests the ability of all age groups to satisfactorily operate the machine via the android control.