STUDY OF TRACTOR VIBRATION AND ERGONOMIC DESIGN OF TRACTOR SEAT FOR OPERATORS COMFORT
|Sr. No. |Content |Page No. | |1 |Objectives |1 | |2 |Introduction |2-4 | |3 |Reviews |5-10 | |4 |Vibration Studies |11-29 | |5 |Ergonomic Design of seat |30-51 | |6 |Summary |52 |
1. To study the tractor vibration in context of discomfort to the operator
2. Ergonomic design of the tractor seat for operators comfort.
In the past, human and animals were the only power sources available for almost all the agricultural works. In the modern age of agriculture, human and animal powers are replaced by mechanical power. Tractors, power tillers, and irrigation pumps are leading machineries for agricultural mechanization in the world as well as in the South East Asian region. Agricultural mechanization has changed the characteristics of labor in agriculture, has also influenced the workload. With the timeliness of operation and increased capacity has resulted the need for higher speeds, bigger and heavier machines. During the operation of these machines by human beings, the load on the operator as well as occupational hazards and diseases are found to be increased, which lead to impair the performance of the operator. In farm works, the fatigue and discomfort to which human beings are subjected is due not only to physical labor, but to vibration and noise as well
The problem of the vibration transmitted through the seat of agricultural tractors to the driver has been widely discussed over the last 40 years (Matthews, 1964a and 1964b). The tractor operator usually is exposed to a comprehensive magnitude of noise and vibration levels. With the constant need to improve the operator comfort and safety, a progress has been made in subsiding noise and the emphasis is being diverted to reduce the ride vibration levels. A large number of options may be considered to improve the ride of an agricultural tractor viz., suitable tyres, primary suspension at front and rear axles, cab suspension, and seat suspension. Large diameter and soft tyres reduce the forces transmitted in the bounce and pitch modes. This option is infeasible due to size limitation on the tyres
The nature of tasks on a tractor necessitates a number of actions to be performed by the operator, which puts varying physiological demands on the body. Examples of these tasks are steering of tractor, looking backward to observe and control the machine/implement, and force required to operate clutch, brake, and hydraulic control lever. The task and workplace determine the postures and create a pattern of loading on the structures of the body of the individual. The seat is one component affecting these loads. Tractor seat design can be used as a means to modify loads on the body structures to reduce operator’s discomfort. The tractor seat system must withstand the rigorous forces during different field operations and still maintain their dimensional stability, firmness and essential characteristic that enable the seat to retain its contoured shape
Vibrations experienced by the driver at the tractor seat lie especially in this vulnerable...