Vibration Control Project_Manjunaaath.pptx

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1. TRACTOR RIDE VIBRATION CONTROL BY MANJUNATHA A V Roll No: 2302103044 MTech-Mechanical System Design

2. Content Introduction Types of Tractor Vibration Effect of Vibration Subject Response to WB Vibration Vibration Evaluation Prediction of Tractor Ride Vibration Improving Operator Comfort References

3. Introduction Vibration occurs in all moving bodies and tractors are no exception The frequency range of 2-6 Hz has been observed to be the most harmful for the human operator Suspended seats fitted to most Tractors reduce the vertical component of vibration, but the levels are still undesirably high Introducing wheel suspension makes the system complicated and costly Cab suspension is another method of reducing ride vibration which is almost as expensive as wheel suspension The objective of this review is to collect information regarding tractor vibration and research work done to date to reduce it at the operator's level

4. Types of Tractor Vibration Vibrations primarily are of two types: sinusoidal and random Sinusoidal vibration is regular in nature and predictable Random vibration is irregular and unpredictable. The mechanical vibrations that affect the human body can be grouped into two directional vibrations, i.e. rectilinear and rotational The rotational mode of vibration does not usually cause much discomfort but over rough terrain region more disturbing than rectilinear vibrations. Directions of basicentric coordinate system for mechanical vibrations influencing the human body

5. Effect of Vibration Physiological effect The transmission of excessively large forces to the body. Pressure exerted over a long period of time can cut off blood supply to the tissue and cause mechanical damage Buttock problem while sitting for extended time periods Health effect of whole body vibrations Performance effects of vibration

6. Subject Response to WB Vibration Equal sensation contours produced in the laboratory by different investigators.

7. Vibration Evaluation Four physical factors of primary importance in determining the human response to vibration - namely intensity, frequency, direction and the duration of the vibration In the practical evaluation of any vibration, physical description can be given in terms of above 4 factors Fatigue-decreased proficiency Exposure limit Reduced comfort boundary Vertical (az) acceleration limits as a function of frequency and exposure time: fatigue-decreased proficiency boundary

8. Prediction of Tractor Ride Vibration Transverse (ax, ay) acceleration limits as a function of frequency and exposure time: fatigue decreased proficiency boundary Several studies have simulated the ride vibration characteristics of unsuspended tractors. very few cases simulations have been tested against measured results Dale  has described a linear frequency domain simulation based on a rigid body tractor with a pivoted front axle and linear tyre characteristics Crolla etal . showed that root mean square (rms) accelerations in excess of 40% are not unusual, and that, for some tractors

9. Improving Operator Comfort Suspended seat with Fixed OOS Suspended Seat with Suspended OOS Suspended Seat with Fixed Cab Suspended Seat with Suspended Cab Mechanical model of seat with the operator as a single degree damped spring mass system Two degrees of freedom model of a suspension seat + Cab

10. References https://www.researchgate.net/publication/222329289_Tractor_ride_vibration-A_review by NIRANJAN PRASAD*, V. K. TEWARI* and RAJVIR YADAV* https://png.toolxox.com/kidp?p=iwRxhh_old-tractor-clipart-antique-tractor-clipart-black-and/ - Page 1 https://www.researchgate.net/figure/Resonance-frequencies-of-human-body-organs_tbl1_274471590 - Page 6 https://www.deere.com/en/tractors/utility-tractors/5-family-utility-tractors/ - Page 9