Field an experiment was carried out in the farms of Agriculture and forestry academy at University in Nineveh. The research was conducted to investigate a practical study for the effect of four forward speeds (1.9, 2.6, 3.8 and 4.7 km/hr.) and three acceleration direction of axes lateral, longitudinal and vertical, and two types machines control (Mower and Rotovators) on the vibrations transferred to the steering wheel horticulture tractor type (Goldoni). The vibration points on the handgrip were calculated and tested. Root mean square acceleration (RMS), given in m/sec 2, was calculated. Results showed increased acceleration vibration of the three directions (longitudinal, lateral and vertical) transferred to the steering wheel tractor by increased forward speed. The Mower score recorded the highest acceleration vibration for the three directions of Rotovators. The levels of vibration emitted from tractor to hand an operator during the experiment was high comparing with standard mechanical vibration. Handgrip vibration intensity in the vertical direction is bigger than the lateral and longitudinal direction. The total vibration evaluating was denoted as the square root mean of the three sum value (lateral, longitudinal and vertical) directions. The paper purpose was measuring and analyzing vibration level transferred to the steering wheel and reduces the machine vibration. This paper is helpful for design in order to increase the develop safety systems in easy and economical way.
Workers often suffer in heavy, especially those who are using. The equipment with the nature of the seismic events of significant health problems was encouraged to study and analyze and measure the vibration of workers in this area, which is one of the most interesting engineering applications. This physical factor that acts on the human body is vibration which transmits the mechanical energy from sources of oscillation [
A field experiment was conducted at experimental field of agriculture and Forestry College at the University of Mosul in the north west of the city of Mosul.
The implementation of the horticulture Goldoni tractor search type is shown in
Used two types control machines (Mower) width work 120 cm and (Rotovators) width work 85 cm as shown in (
Soil type was clay-silt as shown in (
Used vibration meter type (Adash4900-vabrio M) to measure the vibration force
Technical characteristics | |
---|---|
Type | Goldoni 10 s |
Model | Professional two-wheeled tractor 3200 |
Rated power | 6.4 KW/8.5 HP |
Number of cylinders | 1 |
Nominal rate | 3600 rpm |
Cooling | Air |
Gear | 4 normal, 4 low |
Length (front bumper/rear handle bar) | 1795 mm |
Weight with wheels and rotary cultivator | 153 Kg |
Set of wheels 5.00 × 10'' on adjustable disc | Obtainable widths: 533 mm - 553 mm - 621 mm - 661 mm |
Clutch | Dry monodisc, diameter 4.3'' |
Type transmission | Mechanical traction, with endless screw and oil bath gears |
Security | Gears top device on the handlebar grip |
of the three orthogonal directions (longitudinal: Yh), (vertical: Zh) and (lateral: Xh), hand grip shown in (
The device consists of sensor vibration which contains the introduction of the magnet secures the required surface measurement relates to mainstream sensor rattled by wire measurement device that contains the digital display shows the values of the vibration. The vibration was sensitive side and portrait layout according to the system for the hand as shown in the (
The quantity used to describe the magnitude of vibration shall be the frequency weighted acceleration in meters per second squared (m/s2), expressed as a root-mean-square. As, it is important that for additional purposes frequency spectra must be acquire, the frequency weighted acceleration can get using ISO 5008:
Mean characteristics | ||
---|---|---|
Soil | Value | Unit |
Sand | 15.4 | (%) |
Silt | 40.0 | (%) |
Clay | 44.6 | (%) |
Soil bulk density | 1.329 | (Mg/m3) |
Soil moisture content | 13.8 | (%) |
Cone index | 12.45 | (kg/cm2) |
2002 was estimate by analyzing the range of 1/3 of octave using acceleration values:
a h . w = [ ∑ j = 1 n ( w j a w . j ) 2 ] 1 / 2 (1)
where: ɑh.w frequency weighted acceleration in the direction i (i = x, y or z), ɑwj is the acceleration acquired (m/sec2) and Wj is dimensionless weighting factor as given in (
It is also important vibration measure location shall be as close together as possible that significantly affect the measured value.
In consensus with the indicated ISO standards, the three directions of an orthogonal coordinate system, in which the vibration accelerations should be accounted, were as follows: z-axis, x-axis and y-axis.
In accordance with ISO 5349 the assessment of vibration exposure depends on a quantity that combines all three axes. This is weighted acceleration sum or vibration total value it is defined as the root-mean-square of the three constituent values:
a h v = a h w x 2 + a h w y 2 + a h w z 2 (2)
where: ɑhwx; ɑhwy; ɑhwz are frequency weighted acceleration values for the single axes.
The vibration exposure depends on the duration of the exposure and on the magnitude of the vibration total value. Daily exposure duration is the total time for which the hands are exposed to vibrations during the working day. The daily vibration exposure should be expressed in terms of the 8-hour energy-equivalent acceleration or frequency-weighted vibration total value:
A ( 8 ) = a h v T T 0 (3)
where: T is the total daily duration of the exposure (sec), and T0 is the reference duration of 8 h.
When total daily vibration exposure contains many process, with various vibration magnitudes, the daily vibration exposure, A (8 hours) shall be calculates using:
A ( 8 ) = 1 T 0 ∑ i = 1 n a h v i 2 x T i (4)
where ɑhvi is the vibration gross rate for i the process, n is number of single exposures, and Ti is the period of i the process.
The total daily vibration exposure calculated approximately 3.5 (hr.) working day the operator spends, in Mower, and spends approximately 2 (hr.) in Rotovators:
A ( 8 ) F o r . L 1 = 1 28800 ( 12600 × 21.84 2 + 7200 × 20.56 2 ) = 17.73 m / sec 2
A ( 8 ) F o r . L 2 = 1 28800 ( 12600 × 27.84 2 + 7200 × 26.65 2 ) = 22.72 m / sec 2
A ( 8 ) F o r . L 3 = 1 28800 ( 12600 × 33.54 2 + 7200 × 32.15 2 ) = 27.39 m / sec 2
A ( 8 ) F o r . L 4 = 1 28800 ( 12600 × 39.78 2 + 7200 × 38.55 2 ) = 32.61 m / sec 2
Weighted acceleration sum (WAS), forward speed, vibration value for all the direction, for tow machines, and their presentation are shown in
Note from
As indicated in
Type Machine | Mower | |||||
---|---|---|---|---|---|---|
Gear box No. | Accelerate direction | Measuring number | Mean value | |||
1 | 2 | 3 | ||||
L1 | x y z WAS | 10.40 8.50 17.40 | 10.20 8.30 17.50 | 10.00 9.00 17.00 | 10.20 8.60 17.30 21.84 | |
L2 | x y z WAS | 13.40 10.50 21.60 | 13.0 10.80 21.40 | 14.00 10.80 22.70 | 13.47 10.70 21.90 27.84 | |
L3 | x y z WAS | 16.50 12.50 26.00 | 16.90 12.20 26.10 | 17.00 12.20 26.80 | 16.80 12.30 26.30 33.54 | |
L4 | x y z WAS | 19.50 13.50 31.80 | 19.30 13.90 32.00 | 18.80 14.00 32.20 | 19.20 13.80 32.00 |
L1 = 1.9 km/h; L2 = 2.6 km/h; L3 = 3.8 km/h; L4 = 4.7 km/h.
Type machine | Rotovators | |||||
---|---|---|---|---|---|---|
Gear box No. | Accelerate direction | Measuring number | Mean value | |||
1 | 2 | 3 | ||||
L1 | x y z WAS | 9.50 8.00 16.60 | 9.20 8.20 16.30 | 9.50 8.10 16.30 | 9.40 8.10 16.40 20.56 | |
L2 | x y z WAS | 13.00 9.90 21.20 | 12.80 9.60 21.00 | 13.20 9.90 21.10 | 13.00 9.80 21.10 26.65 | |
L3 | x y z WAS | 15.60 11.50 25.50 | 15.90 11.90 25.20 | 16.10 11.70 25.50 | 15.87 11.70 25.40 32.15 | |
L4 | x y z WAS | 18.20 13.20 31.30 | 18.60 13.50 31.00 | 18.40 13.20 31.30 | 18.40 13.30 31.20 38.55 |
L1 = 1.9 km/h; L2 = 2.6 km/h; L3 = 3.8 km/hl; L4 = 4.7 km/h.
be due to the Mower consider equipment to control the Plant Holt through increased dramatic inequalities in the soil, leading to a decline in the front of the tractor speed and increase the effectiveness of the force in the soil vibration attenuation while Rotovators consider equipment to control the Plant Holt on the soil surface without depth in the soil. These results agree with [
Types machines | Forward speeds | Acceleration direction | ||
---|---|---|---|---|
X | Y | Z | ||
Mower | L1 | 10.2 | 8.60 | 17.30 |
L2 | 13.56 | 10.70 | 21.90 | |
L3 | 16.80 | 12.30 | 26.30 | |
L4 | 19.20 | 13.80 | 32.00 | |
Rotovators | L1 | 9.40 | 8.10 | 16.40 |
L2 | 13.00 | 9.80 | 21.10 | |
L3 | 15.90 | 11.70 | 25.40 | |
L4 | 18.40 | 13.30 | 31.20 |
L3, L4) highest recorded total vibration were the results (21.84, 27.89, 33.54, 39.79) Hz respectively, while the interaction between the Rotovators and forward speed (L1, L2, L3, L4) less value recorded total vibration were the results (20.56, 26.65, 32.16, 38.58) Hz respectively. It is clear from this the Mower with the fourth speed record the highest value, while the Rotovators with the first speed record the less value.
As indicated in
・ The velocity of the tractor had the strongest effect on the vibration transmitted from the steering wheel to the hands of the driver from all axis.
・ Hand-arm vibration intensity is greater in the vertical direction than the lateral and longitudinal direction.
・ Like these value acceleration (rms) effects on driver and caused discomfort, will produce finger blanching, tired, and less performance and not completely control operation to the tractor by driver, and also appear the type of machine influence on the vibration.
The authors declare no conflicts of interest regarding the publication of this paper.
Dahham, G.A., Muhamed, S.T. and Saleh, S.M. (2019) Practical Study for the Effect of Speed, Direction of Acceleration and Type of Machine on Vibrations Transferred to the Steering Wheel Horticulture Tractor Type (Goldoni). Engineering, 11, 48-58. https://doi.org/10.4236/eng.2019.111005