Citation
Abdulkadir, Tukur Daiyabu
(2019)
Design and development of a seeding machine for system of rice intensification seedling tray.
Doctoral thesis, Universiti Putra Malaysia.
Abstract
The manual seeding of the system of rice intensification (SRI) seedling tray is labor
and time intensive, therefore, there is need to have a machine for the seeding process. In this
study a seeding machine for SRI seedling tray was designed, developed and evaluated. The use of
vacuum suction as a tool for single seeding of paddy seed to SRI seedling tray was conceived.
The amount of vacuum pressure required for single seeding of MR219 paddy seed was determined
using existing models and evaluated experimentally. Cone angle and seed-hole diameter as important
nozzle parameters were determined and evaluated experimentally. A vacuum seeding manifold with 924
seeding nozzles was proposed for the SRI seedling tray seeding process.
Computational fluid dynamic (CFD) software was used to optimize the manifold design,
where the effect of number of suction outlets on vacuum pressure uniformity was investigated. The
effect of vacuum chamber type on vacuum pressure distribution uniformity was also investigated,
where two manifold types with cylindrical and rectangular vacuum chambers were compared using
CFD. Two types of pick and place mechanisms, which are screw mechanism and crank rocker
mechanism, were proposed and compared analytically for best performance in terms of
operational speed. The strength of the links of the crank-rocker pick and place mechanism was
simulated using finite element analysis (FEA). The flow property of seedling growing media in
relation to hopper material surface was studied using Jenike’s procedure, where the optimum
hopper angle was determined for development of seedling media hopper. A seeding machine was
developed for SRI seedling tray. The machine consists of three basic sub systems synchronized to
work as a single unit, these are: media placement system that place planting media to the
seedling cavities before and after seed placement; seed placement system that place single seed per
seedling cavity; and tray conveying systems that transport the seedling tray from beginning to the
end of the seeding process. In operation, one operator places a seedling tray on the conveyor at
one end of the seeding machine. The conveyor transports it to pass below a media hopper. A first
layer of media is sprayed on the tray. When the tray reaches seed placement section, an
object detection sensor detects its presence and stops the conveyor. The seed placement mechanism picks the seeds from a seed tray and places
them into the seedling cavities with the aid of vacuum suction and solenoid valve. The tray is then
transported to pass below a second media hopper where the seeds are covered. A third
operator removes the seeded tray from the conveyor. The machine performance was evaluated based on
media placement and single seeding capability. The amount of vacuum for single seeding of MR219
seeds was found to be between
18.3 and 29.15 mbar. Experimental evaluation of this vacuum pressure has shown that the optimum
vacuum pressure for single seeding of paddy seed is 30 mbar. The optimum seed-hole
diameter was found to be 1 mm and was adopted for the seeding manifold development. The effect of
number of suction outlets on vacuum pressure distribution uniformity was not significant. For
seeding manifold with 924 seeding nozzles, manifold with rectangular vacuum chamber type was found
to have a better pressure distribution uniformity than manifold with cylindrical vacuum chamber
type. Crank-rocker mechanism with a theoretical operational period of 1 second per pick and place
circle was found to have a better performance than the screw mechanism with 78.8 second per pick
and place circle. A safety of factor of 4.64 ul was obtained from the FEA analysis for
mechanism links. The hopper angle for mass flow of planting media was found to be 22ᵒ.
The evaluation results of the seed placement mechanism have shown that seeding without seed
tray vibration has a better performance, where the best performance of 75% single seeding, 0%
multiple seeding and 25% miss seeding was achieved. The results of evaluation with vibrating seed
tray have shown a top performance of 46% single seeding, 0% multiple seeding and 54% missed
seeding. A mean media depth of 18.32 mm was achieved. The field capacity and efficiency
of the machine were found to be 1 tray/14 s (1 ha/ 0.67 hour)
and 61.43% respectively.
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Additional Metadata
Item Type: |
Thesis
(Doctoral)
|
Subject: |
Agricultural engineering |
Subject: |
Agricultural machinery |
Subject: |
Rice - Equipment and supplies |
Call Number: |
FK 2019 130 |
Chairman Supervisor: |
Muhammad Razif Mahadi, PhD |
Divisions: |
Faculty of Engineering |
Depositing User: |
Ms. Nur Faseha Mohd Kadim
|
Date Deposited: |
16 Nov 2020 05:41 |
Last Modified: |
04 Jan 2022 03:30 |
URI: |
http://psasir.upm.edu.my/id/eprint/84174 |
Statistic Details: |
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