摘要 |
<p>A self-propelled vehicle first goes down a selected path with the help of a person's guidance from a starting place to a target point. It receives positioning signals from a positioning system and stores them in a data memory. If the vehicle later follows this selected path automatically, it receives from the positioning system at a starting-point a current position signal that is compared with the position of the starting place. If these positions do not agree, an evaluating device calculates direction and distance to the starting place. By using current positioning data received in sequence, each direction and distance is calculated to the next stored position and the appropriate path is followed.</p> |