Effect of Hitch Height on Wheel Slip and Stability of 2WD Tractor

A S-type load cell was installed below the front axle of a 2WD tractor to record the dynamic load of the front axle. The load was recorded with the help of a data logger (DT800). Theoretical and actual speeds of the tractor were measured with proximity sensor and non-contact type radar sensor, respectively to calculate the wheel slip. The test was conducted on two types of road surfaces namely tarmacadam surface with slopes of 0°, 3.4° & 4.8° and unpaved surfaces with slopes of 0°, 2.86° and 5.61° with payload of 2, 2.5 and 3 tons on trailer at hitch heights of 45, 55 and 60 cm above the ground. It was observed that dynamic load on the front axle and slip decreases from 603 kg to 438 kg and 8.65 to 5.49 %, respectively on raising the hitch height from 45 cm to 60 cm above the ground at a payload of 2 tons on the trailer. Similar results were obtained on all payloads at different slopes and road surfaces. Lowering the hitch height resulted in the reduction of weight transfer from the front to the rear axle from 32 to 7 % of the static weight of the front axle thereby improving the stability of the tractor.