公开(公告)号：US06317683B1

公开(公告)日：2001-11-13

申请号：US09680162

申请日：2000-10-05

申请人： Joseph Ciprian ,  Bishnu P. Phuyal ,  Robert Fernekes ,  David S. Lampert

发明人： Joseph Ciprian ,  Bishnu P. Phuyal ,  Robert Fernekes ,  David S. Lampert

IPC分类号： G06F16500

CPC分类号： G01C21/30

摘要： A program and method are disclosed that provide for determining a position of a vehicle relative to a road network represented by a geographic database. An intermediate position density is determined along a plurality of road segments in the road network by shifting a prior position density which had been determined along the plurality of road segments by a distance traveled by the vehicle since the prior position density had been determined. Then, the intermediate position density is modified to take into account sensor-derived data received since the prior position density had been determined to form a new position density. The sensor-derived data include data indicating three metrics, namely (1) a position of the vehicle, (2) a heading of the vehicle, and (3) a curvature history. The curvature history represents a change of heading of the vehicle as a function of distance. Then, the position of the vehicle is determined to be that location along the plurality of road segments at which the new position density is greatest. Also disclosed is a program and method that operate when it has been determined that the vehicle has just completed a turn. According to this program and method, processed data values from the sensors that indicate the vehicle position are adjusted to correspond to a position along the road network as represented by the geographic database. Further, if it has been determined that the vehicle is located on a straight road segment after having completed a turn, processed data values of the sensors that indicate a vehicle heading are adjusted to correspond to the heading of the straight road segment upon which the vehicle has been determined to be located.

摘要翻译： 公开了一种程序和方法，其提供用于确定车辆相对于由地理数据库表示的道路网络的位置。 由于已经确定了先前的位置密度，所以沿道路网络中的多个道路段确定中间位置密度，该位置密度是沿着多个道路段确定的先前位置密度移动车辆行进的距离。 然后，修改中间位置密度以考虑从先前位置密度确定以形成新的位置密度而接收到的传感器衍生数据。 传感器得出的数据包括指示三个度量的数据，即（1）车辆的位置，（2）车辆的航向，以及（3）曲率历史。 曲率历史表示作为距离的函数的车辆的航向的改变。 然后，车辆的位置被确定为沿着新位置密度最大的多个路段的位置。 还公开了当确定车辆刚刚完成转弯时操作的程序和方法。 根据该程序和方法，调整来自表示车辆位置的传感器的处理数据值，以对应于由地理数据库表示的沿道路网络的位置。 此外，如果已经确定车辆在完成转弯之后位于直线路段上，则指示车辆行驶的传感器的处理数据值被调整为对应于车辆的直线路段的航向 已经确定要找到。

公开(公告)号：US06502033B1

公开(公告)日：2002-12-31

申请号：US09680161

申请日：2000-10-05

申请人： Bishnu P. Phuyal

发明人： Bishnu P. Phuyal

IPC分类号： G01S502

CPC分类号： G01C21/30

摘要： A turn detection algorithm is used by a navigation system for determining position and heading of a vehicle relative to a road network represented by a geographic database used by the navigation system. A dead-reckoned position and heading are determined along a plurality of road segments in the road network using sensor measurements of a distance traveled by the vehicle and a change in heading of the vehicle. A vehicle trajectory history is formed and then continuously updated. The vehicle trajectory history includes sensor-derived data representing the vehicle trajectory over a relatively small, chosen distance. The sensor-derived data in the vehicle trajectory history include total turn (i.e., heading change of the vehicle), vehicle state (e.g., travelling straight, turning or reversing in turn direction within a specified small distance) and type of vehicle maneuver. These data represent the trajectory of the vehicle for that distance and are kept in a memory. Corresponding data for the same distance interval are also obtained from GPS measurements and the geographic database. Using the data in the vehicle trajectory history and the corresponding data from the GPS and geographic database, a corrected dead-reckoned position and heading are determined. In addition, using the data in the vehicle trajectory history and the corresponding data from the GPS and geographic database, bias and scale factor correction parameters for the sensors are also obtained.

摘要翻译： 导航系统使用转弯检测算法来确定车辆相对于由导航系统使用的地理数据库表示的道路网络的位置和方位。 使用传感器测量车辆行驶的距离和车辆行驶方向的变化，沿道路网络中的多个路段确定死位位置和航向。 形成车辆轨迹历史，然后不断更新。 车辆轨迹历史包括表示在相对较小的选择距离上的车辆轨迹的传感器导出的数据。 车辆轨迹历史中的传感器导出的数据包括总转弯（即，车辆的行驶变化），车辆状态（例如，行进直线，在特定的小距离内的转向或反向）和车辆操纵的类型。 这些数据表示车辆对该距离的轨迹并保存在存储器中。 也可以从GPS测量和地理数据库获得相同距离间隔的相应数据。 使用车辆轨迹历史中的数据和来自GPS和地理数据库的相应数据，确定校正的死位位置和航向。 另外，使用车辆轨迹历史中的数据和来自GPS和地理数据库的相应数据，也可以获得传感器的偏差和比例因子校正参数。

公开(公告)号：US06571195B2

公开(公告)日：2003-05-27

申请号：US09911890

申请日：2001-07-24

申请人： Bishnu P. Phuyal ,  Nicholas E. Smith

发明人： Bishnu P. Phuyal ,  Nicholas E. Smith

IPC分类号： G06F1500

CPC分类号： G01C21/20

摘要： A method for calculating a distance between a first point and a second point using linear interpolation is provided. The first point and the second point are located between a first latitude and a second latitude. An interpolated prime vertical radius of curvature value for a point between the first point and the second point is calculated based on a first prime vertical radius of curvature value for the first latitude and a second prime vertical radius of curvature value for the second latitude. An interpolated meridian radius of curvature value for the point between the first point and the second point is calculated based on a first meridian radius of curvature value for the first latitude and a second meridian radius of curvature value for the second latitude. An interpolated cosine value for the point between the first point and the second point is calculated based on a value representing a cosine of the first latitude and a value representing a cosine of the second latitude. The distance between the first point and the second point is then calculated based on the interpolated prime vertical radius of curvature value, the interpolated meridian radius of curvature value, and the interpolated cosine value. The use of interpolated prime vertical radius of curvature, meridian radius of curvature, and cosine avoids use of non-linear function evaluation. As a result, the process is efficient and the calculated distances are sufficiently accurate.

摘要翻译： 提供了使用线性内插来计算第一点和第二点之间的距离的方法。 第一点和第二点位于第一纬度和第二纬度之间。 基于用于第二纬度的第一纬度和第二主垂直曲率半径值的第一主垂直曲率半径值来计算第一点和第二点之间的点的内插主垂直曲率半径值。 基于用于第二纬度的第一纬度和第二子午线曲率半径的第一子午曲率半径值来计算针对第一点和第二点之间的点的内插子午线曲率半径值。 基于表示第一纬度的余弦的值和表示第二纬度的余弦的值来计算第一点和第二点之间的点的内插余弦值。 然后基于内插的主垂直曲率半径值，内插子午线曲率半径值和内插余弦值来计算第一点和第二点之间的距离。 使用内插的垂直曲率半径，子午曲率半径和余弦避免使用非线性函数评估。 因此，该过程是有效的并且计算出的距离是足够准确的。