Study On Dynamics Of Driving Device Of High-speed Tracked Vehicle

In order to hold the dominant position in land warfare, the realization of high-speedmilitary tracked vehicle is one of the measures that we should take. As the improvement ofengine and electric motor performance, more and more countries have been trying toimprove their tracked vehicles’ speed limit and driving performance on off-road. Some oftheir measures such as the application of more powerful engine and the improvement ofdriving unit have been proven to be applicable, and it can truly improve the performance tosome extent. However, the efficiency of a tracked vehicle is still much lower than awheeled vehicle. So, it is of vital significance to improve the mobility by cutting downlosses of driving unit.The theories of relative coordinate system and recursive algorithm have been appliedto analyze the problem of multi-body dynamics in driving unit of high-speed trackedvehicle. Some of the factors including position, speed, acceleration, constrained force,impact force during the motion process have been studied. Then, a lateral dynamic modelhas been put forward under the circumstance of high-speed, large radius steering.Based on the kinematics and dynamics analysis of a high-speed tracked vehicle, tracktension in high-speed condition has been studied. After setting up the dynamic model,driving system model, vehicle controller model, a series of co-simulation are conducted in70km/h,80km/h,90km/h and100km/h. Then, tension in tight selvedge, loose side andground side are extracted from co-simulation results. Furthermore, the degree that each sideof tension is influenced by velocity, traction force and preload is researched. A comparisonis made between high speed condition and low speed condition. In addition, a track tensionimprovement measure has been put forward. It can reduce28kN~36kN in high speedcondition, and its tension optimization efficiency is about10%~16%.Sprocket loss between track link and sprocket, hysteresis loss of rubber bushes, rollingloss between roller and track, impact loss between track and carriers have been studied. Theinfluencing factors of each part of loss have been researched. After co-simulating in certainconditions, proportion of each part of loss and its changing trend in starting stage, lowerspeed stage, high speed stage have been obtained. Lastly, measures to improve theefficiency of driving unit have been put forward. On the one hand, using lighter track canreduce the tension caused by centrifugal force. On the other hand, adding an extra track tension unit can decline the vibration without tension increasing in high speed condition.