依据模拟驾驶区段的工务数据,在模拟驾驶过程中实时地生成三维视景.根据平面几何和立体几何的基础知识,设计三维空间直线和圆曲线对象的空间走向求解公式,以及以线路中心线为基准的纵断面顶点坐标求解公式.在将坡道、曲线重新组合的基础上,以线段为单位,计算轨道线路中心线的空间走向,根据线路、设备(设施)的纵断面结构,依据线路中心线的空间走向,求解纵断面的顶点坐标,构造三维视景所需要的三维平面要素.同时结合列车的运行状态,确定列车的空间方向,将线路的三维视景经三维平移、旋转得到驾驶场景.使用结果表明,三维虚拟场景能够还原真实场景,帧频率可达25fps,满足真实和实时的要求.
Based on the data of driving simulation section in railway system, three-dimensional (3D) scene is generated in real time during the process of railway simulation. According to the basic knowledge of plane geometry, solid geometry, and the formula of plane geometry, a calculation formula is proposed to solve the spatial location of line and circular curve in 3D space. Another formula is also proposed to calculate the vertex coordinate of vertical section using railway track' s centre line as a benchmark. The ramp and curve are recombined and the spatial location of railway track' s centre line is then calculated based on the line unit. In view of the vertical section of railway line and facility, the vertex coordinate of vertical section and the required elements of 3D space can be obtained on the basis of spatial location of railway track' s centre line. The spatial location of the train is determined considering train running status. Driving scene is obtained after 3D translational motion and rotary motion to railway line. The applications show that 3D virtual display can restore the real scene and the frame frequency is 25 fps, which meets the requirements of the true and real time.