Mosambi
3.9 AGRICULTURAL ENGINEERING
3.9.1 Modified Vegetable Seed Extractor
The modified vegetable seed extractor was evaluated for extraction of bottle gourd and brinjal (round) seeds.
Bottle gourd fruit was chopped into 5-7.5 cm long pieces
and fed to machine. With the introduction of blades onto the cylinder of the modified extractor, a substantial improvement in throughput capacity was observed. A throughput capacity of 120 kg/h was achieved as against 30-40 kg/h in the earlier model. The recovery of seed was 4.37% and germination of these seeds was 82%. In the case of brinjal, when fed as whole fruit in batches of 5 kg, the throughput capacity was observed to be around 100 kg/h and seed extraction about 3%. It was observed that there is a need to modify the feeding hopper to achieve higher feeding rate. A motorized operation is necessary for continuous operation, and to achieve 100-120 rpm of cylinder, a gear box needs to be incorporated.
3.9.2 Ergonomic Evaluation of Manual Rotary Power Generation
Manual energy is extensively used to operate various hand tools and devices in agricultural production system. The human energy can be converted into rotational power through simple mechanical devices. The conversion efficiency and power output in these modes vary significantly with respect to duration, load and group of muscles involved. To find out the best possible human posture to facilitate optimum combination of muscles to generate rotational power, an experimental device, Postural Dynamometer, was developed and modified with loading facilities.
3.9.2.1 Objective and subjective evaluation of manual rotary power generation
Experiments were conducted on three modes, viz., handle, pedal and rocking at mechanical power output of no external load, 0.05 HP and 0.1 HP. The objective evaluation in terms of heart rate and oxygen consumption was done.
The mean heart rate values varied from 105 to 160 beats min-1 in different modes. Similarly, oxygen consumption values varied from 0.6 to 1.5 lit/min. Oxygen consumption is one objective indicator of human effort. In all the three modes of rotary power generation, the pedal mode of operation had lower values of energy expenditure as compared to the rest of the two. Subjective evaluation in terms of Body Part Discomfort Score (BDPS) and Overall Discomfort Score (ODS) were the lowest in pedal operation mode at all the power outputs. The human efficiency, ratio of mechanical output to human efforts ranged from 10 to 18%. The human efficiency was also the highest in pedal Two modified methods were developed to enhance the
manual output.
Based on the results and ergonomic considerations, a sowing table with seeding tray (T2) for manual operation was developed and tested. It was found that by simple improvisations, output capacity of one person could be increased by more than 25% as compared to the traditional method of tray sowing.
Observations in different unit operations of plug tray seeding
Item Average time required (min)
T0 T1 T2
Making indents in tray cells 1.05 0.24 0.24 Placing seeds in tray cells 7.78 6.94 6.16
Unproductive time 1.93 1.5 1.6
Total time 10.76 8.68 8.0
Saving in time 2.08 2.76
Increase in output (%) 19.3 25.6
Vegetable seed extractor
operation, which was in the vicinity of 15 to 18%, as an outcome of postural comfort as compared to other modes and low oxygen consumption.
3.9.3 Design and Development of Aqua-ferti-seed drill with Constant Head Gravity Feed Metering of Aqueous Fertilizer
A tractor-drawn aqua-ferti-seed drill with constant head gravity feed metering of aqueous fertilizer using rotary gear pump was developed. This is an improvement over the tractor-drawn aqua-ferti-seed drill based on peristaltic pumping system developed earlier. The heart of the machine is an aqueous fertilizer metering system using constant head gravity feed mechanism with variable nozzle sizes. The design of the machine consists of a main frame,
a metering system for both seed and aqueous fertilizer, furrow openers, ground wheels and a power transmission system. The aqueous fertilizer metering was attained by designing a suitable pumping system to deliver a measured quantity of aqueous fertilizer. The constant head in the gravity feed tank at different combinations of head and nozzle opening was maintained by varying the speed of rotary pump suitably.
Keeping in view the viscous and corrosive nature of the aqueous fertilizer, a rotary gear pump with a discharge rate of 60 l/min and an rpm range of 1450 was found suitable for pumping aqueous fertilizer to the central tank for maintaining the desired constant head. A fluted roller type seed metering mechanism having flute of proper size and shape was considered for metering of wheat seed. The range
of seed rate with the system was between 80 kg/ha and 125 kg/ha, which met the requirement of dryland areas. A furrow opener of size 438x40x6 mm was designed. Two mild steel tubes were welded to facilitate the application of seed and aqueous fertilizer separately at a distance of 5 cm to avoid direct fall of aqueous fertilizer over the seed. The ground wheel was designed as per RNAM test code, i.e., 360 mm diameter which lies in the specified range of 350-450 mm.
Based on functional test evaluation, the actual field capacity and field efficiency of the machine were 0.36 ha/h and 67%, respectively. The machine gave uniform discharge from its different nozzles. The percentage increase in soil moisture due to aqueous fertilizer application at the rate of 8000 l, 6700 l and 6000 l/ha were 241%, 196% and 117%, respectively, as against 8% loss in the case of control plot just after sowing. For 8000 l/ha aqueous fertilizer rate, the increase in germination, number of shoot per plant, number of ear head, plant height, grain yield and straw yield were 51%, 48%, 38%, 11%, 38%, and 60%, respectively, in comparison to those for no aqueous fertilizer. The cost of the machine is estimated at Rs. 27,000 with break even point (BEP) 49% of annual utility of 200 hours and pay back period of 3 years. It could make possible the sowing of wheat in dryland areas where seeding is not possible in many instances.
3.9.4 Agricultural Mechanization –A Major Drift through Custom Hiring
A survey in Haryana and western U.P. revealed that custom hiring is picking up not only in combine harvesting but in tillage and sowing/planting operations also. A major drift from linearity in mechanization has been observed in crop harvesting operation through introduction of combine harvesters on custom hiring. The combine owners of this area send a team of four persons - foreman, driver and two helpers to adjoining states including Gujarat, Maharashtra, Madhya Pradesh, Uttar Pradesh (Agra region). The time and space of journey is arranged keeping the crop maturity in mind. A business of Rs. 3 lakh per visit was reported by the combine owners.
Custom hiring in tillage has brought change in western U.P. and machine ownership pattern has shifted from cultivator and harrow to rotavator. The reason behind this shift is time saving due to higher field capacity and better
Field evaluation of gravity feed aqua-ferti-seed drill
performance of rotavator. This is advantageous to both customer and service supplier. Similarly, in sowing operation also, custom hiring is catching on. Farmers from western U.P.
with tractor and potato planter system have gone up to Agra for performing custom-services. The average annual use of tractors was for 990 hours; of which 86% use was for custom hiring. The share of custom hiring use in agricultural operations was 73% of the total annual use. It was mainly in land preparation and wheat threshing (34% and 14%), and 2 to 6% in other farm operations as sowing, interculture, transport of inputs and produce.
3.9.5 Okra Planter Seed Box Hopper Bending Fixture
A fixture has been developed for bending the seed box hopper of okra planter. It consists of a base frame, a vertical frame, a pressing unit and a lead screw with guides. Base frame of the fixture has been fabricated by welding of two 400 mm lengths of m.s. channel of section of 80x35x35x5 mm and two 300 mm lengths of m.s. angle of size 40x40x5 mm. Vertical frame is welded on the base frame. It consists of two pillars of height of 415 mm each made from m.s.
channel section of 80x35x5 mm. Horizontal distance between these pillars is 380 mm and the top portions of these are joined by welding another m.s. channel section, and lower portions of these pillars are welded to the base frame in the centre.
Pressing units has been fabricated in two parts, i.e., convex half and concave half. Convex half is closed one whereas concave half is hollow. Height and width of convex half is 140 mm and 80 mm with a radius of 125 mm. Top of convex half is made from 12 mm thick m.s. plate, and its length and breadth is 225 mm and 175 mm, respectively.
Lower half of the pressing unit is hollow concave and is made from 3 mm thick m.s. sheet having 128 mm radius.
Concave is welded to the base frame in the centre and is supported by two side plates and these are welded to vertical frame. Templates have been made for seed box hopper and its top. Mild sheet of 3 mm thickness is cut manually according to template and is placed at top of concave half of pressing unit. The lead screw moves the convex half of the pressing unit. It presses the m.s. sheet placed in between the convex and concave half till the sheet takes the shape of hopper. Afterward convex half is moved upward with the help of lead screw and handle. Top of hopper and the flap are then welded. The average time taken for cutting, bending
and welding is 8 minutes as compared to 18 minutes of normal method, i.e., giving shape by hammer over anvil and channel, and thus there is a net saving of 55% time in fabrication. Beside this, it gives more uniform hopper as compared to normal fabrication method, and the flow of seed in hopper is uniform.
3.9.6 Drying Studies in Solar Cabinet Dryer and Open Sun
An experiment on drying studies on onion was conducted in solar cabinet dryer. Open sun drying was also done to compare the effect of solar cabinet dryer. One kg sample of onion and cabbage was used for drying in the cabinet dryer and open sun drying. The samples were blanched with 10%
sodium meta-bisulphate (KMS) and heated for 10 minutes. The measurement of temperature of the dryer chamber was done with the help of a portable temperature indicator (least count 0.10C) at three central locations in the chamber. The moisture content of onion in solar cabinet dryer (SCD) was reduced from 87.69% to 5.38% in 8 h, while in open sun drying (OSD) it took double the time (16 h) to reduce to 5.38%. The moisture content of cabbage in SCD was reduced from 84.34% to 6.23%
in 10 h while in OSD it took 16 h to reduce to 6.23%. The drying rate was higher at different moisture content in SCD than in OSD. The drying rate was faster at different time in the case of SCD than that of OSD in both the vegetables. The quality of produce dried in solar cabinet dryer was better than that dried in open sun. The average temperature increase of about 140C was achieved in solar cabinet dryer compared to that in the ambient temperature.
3.9.7 Mathematical Model of Green House
A mathematical model of a greenhouse to predict the performance of a particular greenhouse in terms of various design and climatic parameters was used to predict greenhouse air temperature at different times of the day in summer and winter. The inputs for the program are climatic parameters, such as ambient temperature, solar intensity (both averaged over one hour period), and design parameters of greenhouse design, viz., area of greenhouse, volume of greenhouse, transmissivity, etc. The output of the program provides hourly average temperature of the greenhouse enclosure. The greenhouse air temperatures have been predicted on an hourly basis for different seasons. As evident from the following graph, there is a fair agreement between the experimental and predicted values of the greenhouse air temperature. In order to design a greenhouse suitable for different climatic regions, data were
collected for maximum and minimum temperatures for different places in different regions for different months. The variation in yearly maximum and minimum temperatures for different regions was found between 250C and 400C, and 170C and 320C, respectively. In winter, the variation in maximum temperature and minimum temperature was found between 70C and 320C, and -30C and 50C, respectively. During summer, the variation in maximum temperature and minimum temperature was found between 270C and 420C, and 120C and 280C, respectively.
3.9.8 Compaction Characteristics of Barley Straws
Compaction characteristics of barley straw were evaluated. The blocks were tested to evaluate their bulk density, resiliency and compression ratio. Bulk density and compression ratio of the blocks decreased with the increase in moisture
content but increased with the increase in compression pressure, whereas resiliency increased with the increase in moisture content but decreased with the increase in compression pressure.Compression pressure of 3000 PSI was found to be appropriate for making blocks. The molass content of 6-8%
was found suitable for block formation as higher molass content resulted in oozing of molass through air holes in compression chamber and subsequently choking of air holes.
3.9.9 Development of Whole Pulse Grain Polisher
Appearance of whole grains is an important parameter in reference to their commercial value in the market. With this view, a polisher consisting of rubber roller, concave, feed hopper and frame was developed for polishing whole pulse grains. The roller is made of MS pipe coated with rubber.
The machine can be used for improving the appearance and physical quality of whole pulse grains, which would fetch better market price. This also enhances the storage life of the grain. The machine is run by an 2 HP electric motor.
3.9.10 Development of Grain Flaking Machine
Flaking is an important unit operation in food processing.
Therefore, a grain flaking machine was developed to prepare flaked products from maize and jowar. The machine consists of a frame, a hopper, double stainless steel a rollers, a roller gap adjusting mechanism, a roller-rotating mechanism, scrapers and a slanted product collection passage. The machine can be operated both manually and using an electric motor.
3.9.11 Evaluation of Grain Flaking Machine
Flaked grains are widely used as food products. With this in view, a grain flaking machine was developed and evaluated. The capacity of the machine varied from 15 to 30 kg per hour on manual operation. The machine was tested on greengram, wheat, maize and sorghum.
3.9.12 Development of Orange Grader
An orange grading machine, which grades fruits on weight basis, is under development. The grading machine consists of a main frame, a chain conveyor, fruit carrier cups, electronic weighing assembly, LDR laser beam pointer, fruit dropping and collecting mechanism, power transmission system and PCB with ICs. The plastic cups fitted on the chain and containing the orange fruits pass on to the dynamic load
Effect of compression pressure and molass content on bulk density of barley straws
Grain flaking machine
Orange grader under fabrication in the workshop
cell assembly, which would weigh the fruits. The load cell output in the form of varying voltage with respect to time is provided to the IC AD 7730, which converts this into digital form. This digital voltage output for the single fruit is sampled into 10 equal samples and average voltage output is determined, which is proportional to the fruit weight. Once the fruit weight is determined, it is used by a microprocessor to decide which stepper motor is to be operated so that fruit will drop according to the predetermined 4 grades (100-150 g, 150-200 g, 200-250 g, <50 and >250 g). A light dependent resistor and a laser beam pointer have been used to determine the exact location of the fruit carrier cup so that stepper motor will be operated at the exact point of grading.
3.9.13 Farm Operation Services
3.9.13.1 Field operationsThe Farm Operation Service Unit is catering to the needs of the divisions/project directorates/establishments, for conducting field experiments. The Unit has a large area under its control. In order to get uniform germination and stand of crops, the Unit has deployed laser leveler in areas of about 50 acres.
In order to break the hard pan of the soil due to continuous shallow cultivation, summer ploughing was done which improved the soil aeration, and killed some of the insect- pests and weed seeds. Because of summer ploughing, the beneficial microbial activity and fertility of the soil improved.
A massive programme of green manuring was undertaken during kharif to enrich the soil fertility of the Institute farm. During the year, a massive programme of cleanliness was also undertaken, and 80% roads and nalas were cleaned by using manual, chemical and power sources.
Very old imported machines, namely, Norvegion plot seed drill, space planter and Escort combine harvester, and plot thresher were repaired and put to use.
In recent years, a number of micro-experiments were being undertaken by the Institute. The needs of each experiment were unique and the Unit made efforts to satisfy the needs of each experiment.
One of the most important and critical operations is the harvesting of rabi crops. With the help of three very old plot combines, large areas (about 100 acres) under field experiments were harvested. The rest of the crops were harvested with the help of a class combine. The entire harvesting was completed before the onset of monsoon.
3.9.13.2 Irrigation distribution management
The Institute has a very efficient and effective underground irrigation system. The pipelines are 3 feet below the ground and have 105 outlets to irrigate different field plots.
Against specific requisition, a particular outlet is opened to allow water flow and irrigate a specific field plot. Two reservoirs collect water from 18 tubewells during the night and supply it during the day through underground pipelines. During the process of pumping water, sands are pumped and get settled in the reservoir, which reduce the capacity of the reservoirs.
Therefore, the cleaning of reservoir was done on top priority.
In order to supplement tubewell irrigation, canal irrigation water was drawn from Jamuna river and provided to paddy, orchard and agronomy fields.