Kinematic Modeling and Planning of Powered Modular Vehicle Groups

Powered platform vehicles and powered modular vehicle groups are fundamental tools to transport huge-size heavy-duty parts and equipments.A large number of wheels are connected to the steering wheel digitally and actuated independently so that reasonable kinematic modeling and planning of the wheels are essential to make operation of the vehicles effective.According to practical engineering requirements and real-time computation need,two types of advancing patterns are proposed including typical pattern and general pattern.In typical pattern,some fixed point is turned around by powered vehicle and the method of trapezoidal steering analysis is applied to build the wheel angle trigonometric model and the minimum turning radius is found.In general mode,the vehicle goes along a curved path decomposed into segments corresponding to typical patterns.When several platform vehicles are combined into a modular vehicle group digitally,modular idea is introduced that the path of the modular vehicle group is transferred to be paths of platform vehicles firstly by transformation from global coordinate of vehicle group to local ones of platform vehicles and then the wheel angles of each platform vehicle are solved by local computer independently.The presented method is illustrated by case studies.