Route planning method, route planning device and autonomous mobile device

A route planning device for planning a travel route to be used by an autonomous mobile device, which travels along the travel route, before the autonomous mobile device travels autonomously, the device comprising:

• an environmental map acquisition unit arranged to acquire an environmental map showing an obstacle area in which an obstacle exists;
• a movable area extraction unit arranged to extract a movable area from the environmental map acquired by the environmental map acquisition unit and thinning the extracted movable area;
• a route planning unit arranged to plan a travel route from the thinned movable area extracted by the movable area extraction unit by searching for the shortest route to the destination;
• a linearization unit arranged to linearize the travel route planned by the route planning unit without interfering with the obstacle area;
• and
• a smoothing unit arranged to smooth the travel route linearized by the linearization unit without interfering with the obstacle area;
• wherein
• the smoothing unit extracts a point on the linearized travel route and two points on the linearized travel route sandwiching the point, connects the two points with a straight line, and, when the connected straight line does not interfere with the obstacle area, re-sets the straight line as a travel route which connects the two points;
• and
• the smoothing unit smoothes the travel route when an angle formed by the extracted three points is not greater than a certain value that is set forth according to mobility of the autonomous mobile device.