with the collaboration of Iranian Society of Mechanical Engineers (ISME)

Document Type : Research Article

Authors

1 Department of Agricultural Machinery and Mechanization Engineering, Faculty of Agricultural Engineering and rural development, Ramin Agriculture and Natural Resources University, Khuzestan, Iran

2 Department of Mechanics of Biosystems Engineering, Faculty of Agricultural Engineering and rural development, Ramin Agriculture and Natural Resources University, Khuzestan, Iran

Abstract

Introduction: Since the application of pneumatic planters for seeds with different physical properties is growing, it is essential to evaluation the performance of these machines to improve the operating parameters under different pressures and forward speeds. To evaluate the performance of precision vacuum seeders numerous procedures of laboratory and field have been developed and their feed mechanism evaluation is of great importance. The use of instrumentation is essential in laboratory procedures. Many systems have been designed, using instrumentation, to be able to monitor seed falling trajectory and as a result, in those systems the precise place of falling seed in the seed bed could be determined. In this study, the uniformity of seed spacing of a seed drill was determined using of high speed camera with a frame rate of 480 frames s-1. So that, the uniformity of planting was statistically significant under the influence of the speed of seed metering rollers (Karayel et al., 2006). Singh et al. (2005) studied the effects of disk rotation speed, vacuum pressure and shape of seed entrance hole on planting spacing uniformity using uniformity indices under laboratory and field conditions. They reported miss index values were reduced as the pressure was increased but they were increased with increasing of the speed. The multiple indices on the other hand were low at higher speed but they were increased as the pressure was increased. Ground speed was affected by changes in engine speed and gear selection, both of which effect on amount of fan rotation speed for different pressures. The aim of this study was to identify and determine the effects of forward speed and optimum vacuum pressure amount of the pneumatic seeder.
Materials and Methods: The pneumatic planter (Unissem) was mounted on a tractor (MF399) and passed over the soil bin. Thus, the acquired data would be more reliable and practical. To do so, the tractor was equipped with electronic devices for online measurement of various parameters, including: the actual forward speed, wheel sleep percent, drawbar pull, motor RPM, and fuel consumption. Wheel drive of the seed metering mechanism was equipped with Rotary Encoder model S48-8-0360ZT (TK1) to determine the seed disk rotation. For more precise vacuum pressure monitoring, a Vacuum Transmitter model BT 10-210 was used to measure relative pressure from 0 mbar to -1000 mbar. Investigation of seed falling trajectories was conducted using the AVI video acquisition system consisted of CCD (charge-coupled device) camera (Fuji F660EXR) capable of capturing images with a constant speed of 320 frames per second and a spatial resolution of 320×240 pixels. All data were transmitted to a data logger and displayed online on the PC's screen.
For optimization of the factors affecting the performance of the pneumatic planter, the experiments were conducted with: two ranges of forward speeds [3 to 4 km h-1, and 6 to 8 km h-1; three levels of vacuum pressure [-2.5kPa, -3.5kPa and -4.5 kPa]; and two types of seed [cucumber and watermelon], keeping a three-factor factorial experimental design. The tests were replicated three times. The uniformity of seed spacing was measured with indicators described by kachman and smith (1995) which are defined as:
I_miss=N_1/N×100 (1)
I_mul=N_2/N×100 (2)
I_qf=100-(I_mul+I_miss) (3)
P=s_d/x_ref (4)
Which for planting distance of 45 cm, N1 is number of spacing > 1.5Xref; N2 is number of spacing ≤ 0.5Xref and N is total number of measured spacings, Sd is standard deviation of the spacing more than half but not more than 1.5 times, the set spacings Xref, Imiss is the miss index, Imul is the multiple index, quality of feed index Iq is the percentage of spacings that are more than half but not more than 1.5 times, the set planting distance and P is error index.
Results and Discussion: According to the studies on both watermelon and cucumber, the ‘quality of feed index’ value in forward speed rang of 6 to 8 km h-1 was less than one in forward speed rang of 3 to 4 km h-1. Also, the ‘error index’ value in forward speed rang 3 to 4 km h-1 was little rather than forward speed rang of 6 to 8 km h-1, but it was desirable.
For watermelon and cucumber seeds, the ‘quality of feed index’ were the maximum with mean of 97% and 87% under vacuum pressures of -2.5 kPa and -4.5 km h-1, respectively and forward speed of 3 to 4 km h-1; so that for cucumber seed in the mention treatment, the ‘miss index’ was lowest with mean of zero.
The ‘multiple index’ was highest with mean of 6% at 3 to 4 km h-1 forward speed and vacuum pressures of -4.5 for watermelon seed. Values of this index at both forward speed and three levels of vacuum pressures, for cucumber seed was more than watermelon seed.
Miss index values were reduced as the pressure was increased but increased with increasing of speed. With lower vacuum pressure and at higher speeds, the metering disc did not get enough time to pick up seeds, resulting the higher miss indices. On the other hand, the multiple indices were low at higher speed but were increased as the pressure was increased (Panning et al. 2000; Zulin et al. 1991).
Conclusions: It was observed that seed spacing uniformity was affected by both speed and pressure but not equally. Extracted regression models showed that the best uniformity of spacing for watermelon seed obtained at the rang of speed of 3 to 4 km/h and pressure of -3.5 kPa with a error in spacing of 7% in laboratory condition. Furthermore, in field condition the best uniformity of the seed space occurred at the pressure of -2.5 kPa and rang of speed of 6 to 8 km/h with a 9% error. Similarly, for cucumber seed results showed that the best uniformity obtained at the rang of speed of 3 to 4 km.h-1 and pressure of -4.5 kPa in laboratory condition, and at the low speed and pressure of -2.5 kPa in the field.

Keywords

1. Afify, M., Z. El-Haddad, G. Hassan, and Y. Shaaban. 2009. Mathematical model for predicting vacuum pressure of onion seeds precision seeder. Journal of Agricultural Engineering 26 (4): 1776-1799.
2. Alchanatis, V., Y. Kashti, and R. Brikman. 2002. A machine vision system for evaluation of planter seed spatial distribution. Agricultural Engineering International: the CIGR Journal of Scientific Research and Development Manuscript IT 4: 1-5.
3. Allan, J., A. J. Campbell, and C. J. Baker. 1989. An X-Ray technique for determining three dimensional seed placement in soil. Transactions of the ASAE 32 (2): 379-384.
4. Bozdogan, A. M. 2008. Seeding uniformity for vacuum precision seeders. Journal of Scientia Agricola 65 (3): 318-322.
5. Bracy, R., R. Parish, and J. Mccoy. 1999. Precision seeder uniformity varies with theoretical spacing. Hort Technology 9 (1): 47-50.
6. Datta, R. K. 1974. Development of some seeders with particular reference to pneumatic seed drills. The Harvester, Indian Institute of Technology, Kharagpur, India 16: 26-29
7. Drake, T. G. 1991. Granular flow: physical experiments and their implications for microstructural theories. Journal of Fluid Mech 225: 121-152.
8. Gil, E., and R. Carnasa. 1996. Working quality of spacing drills, effects of sowing speed and type of seed. In: International conference on agricultural engineering, Madrid, Proceedings Madrid: AGENG 96: 57-58.
9. Guarella, P., A. Pellerano, and S. Pascuzzi. 1996. Experimental and theoretical performance of a vacuum seed nozzle for vegetable seeds. Journal of Agricultural Engineering Research 64 (1): 29-36.
10. Heege, H. 1993. Seeding methods performance for cereals, rape, and beans. American Society of Agricultural and Biological Engineers 36 (3): 653-661.
11. Karayel, D., M. Wiesehoff., A. Ozmerzi, and J. Muller. 2006. Laboratory measurement of seed drill seed spacing and velocity of fall of seeds using high-speed camera system. Computers and Electronics in Agriculture 50: 89-96.
12. Karayel, D., Z. B. Barut, and A. Ozmerzi. 2004. Mathematical modeling of pressure on a precision seeder. Biosystems Engineering Journal 87 (4): 437-444.
13. Karayel. D., and A. Ozmerzi. 2001. Effect of forward speed and seed spacing on seeding uniformity of a precision vacuum metering unit for melon and cucumber seeds. Journal of the Faculty of Agriculture 14 (2): 63-67.
14. Katchman, S., and J. Smith. 1995. Alternative measures of accuracy in plant spacing for planter using single seed metering. Transactions of the American Society of Agricultural and Biological Engineers 38: 379-387.
15. Kazemi, N., M. Almasi, H. Bahrami, M. J. Shaykh Davoodi, and M. Mesgarbashi. 2014. Efficacy analysis of management major factors affecting on overall energy efficiency of tractor implement by real-time performance monitoring. The 8th National Congress on Agriculture Machinery Engineering (Biosystem) and Mechanization, 29-31 January, Mashhad, Iran. (In Farsi).
16. Kocher, M., Y. Lan, C. Chen, and J. A. Smith. 1998. Optoelectronic sensor system for rapid evaluation of planter seed spacing uniformity. Transactions of the American Society of Agricultural and Biological Engineers 41 (1): 237-245.
17. Lan, M. F., Y. Lan, C. Chen, and J. A. Smith. 1999. Opto- Electronic sensor system for laboratory measurement of planter seed spacing with small seeds. Journal of Agricultural Engineering Research 72: 119-127.
18. Panning, J. W., M. F. Kocher, J. A. Smith, and S. D. Kachman. 2000. Laboratory and field testing of seed spacing uniformity for sugar beet planters. Applied Engineering in Agriculture 16 (1): 7-13.
19. Raheman, H., and U. Singh. 2003. A sensor for flow seed metering mechanisms. IE (I) Journal-AG 84: 6-8.
20. Shafii, S., and R. G. Holmes. 1990. Air jet seed metering a theoretical and experimental study. Transactions of the ASAE 33 (5): 1432-1438.
21. Singh, R. C., G. Singh, and D. C. Saraswat. 2005. Optimization of design and operational parameters of a pneumatic seed metering device for planting cottonseeds. Biosystems Engineering 92 (4): 429-438.
22. Zulin Z., S. K. Upadhyay, S. Safii, and R. E. Garret. 1991. A hydro pneumatic seeder for primed seeds. Transactions of the ASAE 34 (1): 21-26.
CAPTCHA Image