Actuating forces of frequently operated controls on Indian agricultural tractors

Abstract

India is the world's largest operator and manufacturer of agricultural tractors. The ergonomic concerns and incorporating the physical and strength capabilities of the Indian operators were neglected while designing and developing the tractors in India. As a result, there was a substantial mismatch between the operators' capabilities and the forces required to operate the tractors' controls. Therefore, this study was planned to determine the actuation forces of frequently operated controls on popular Indian tractors. Ten agricultural tractors of different makes and models in the power range of 23 to 50 kW were selected for the study. The Sushma steering torque measurement system, Novatech pedal force loadcell, and Gear effort transducer were used to measure the actuation force of the controls, steering wheel, clutch and brake pedal, and gear shifter lever, respectively. The actuation forces required to operate the clutch pedal on selected tractors ranged from 130 to 250 N, well below the IS 10703 (1992) limit of 350 N. Except for one tractor, the brake pedal actuation forces observed for the selected tractors varied from 390 to 670 N, well below the recommended limit of 600 N given by IS 10703 (1992). In static conditions, most tractors' steering wheel actuation forces ranged from 210 to 340 N, exceeding or approaching the 250 N limit set by AIS-042 (2004). In dynamic conditions, when tractors were operated at 3 km/h, the actuating forces for the selected tractors ranged from 90-220 N and were well within the AIS-042 limit.