Development of a MBD simulation model for axle torque prediction of an electric agricultural vehicle

The purpose of this study is to develop an electric all-wheel-drive vehicle simulation model for axle torque prediction. Simulation model was developed using RecurDyn, a multibody dynamics software, and tire-soil interaction parameters were inputted to reflect soil conditions. Driving simulation was performed at a speed of 7.5 km/h, which is the rated speed of driving motor. Traction was inputted between the soil and simulation model, and traction forces were considered as 25, 50, 75, and 100 N. Simulation was conducted for 20 seconds, and for the first 10 seconds, the simulation model was stabilized. As a result of simulation, maximum and average torque was analyzed. On 25 N traction condition, maximum torques of the front left, front right, rear left, and rear right wheels were 19.07, 19.14, 24.37, and 24.37 Nm, respectively. Under 50 N traction conditions, the maximum torques for the front left, front right, rear left, and rear right wheels were 19.49, 19.56, 25.95, and 25.95 Nm, respectively. In the case of 75 N traction, maximum torques were 19.93, 20.00, 27.62, and 27.62 Nm for the front left, front right, rear left, and rear right wheels, respectively. The maximum torques were 20.33, 20.40, 29.25, and 29.25 Nm for the front left, front right, rear left, and rear right wheels, respectively on 100 N traction condition. The average axle torques for the front left, front right, rear left, and rear right wheels were approximately 8.96, 8.95, 6.86, and 6.85 Nm on every traction condition, respectively. It was shown that the axle torque was directly proportional to the applied traction forces. It was noticed that for the initial period, torque on the rear axle was higher than the front axle due to the box located on the rear side of simulation model, and torque on the front axle was higher than rear axle after the initial period because the front axle overcomes the rolling resistance. In this study, the axle torques were analyzed based on various traction forces. However, various conditions like weight and tire parameters would be reflected in the future study.