We Claim:
1. A method of preparing a navigation autonomy map for a
vehicle covering a zone including path segments, the
method being characterized in that it comprises the
5 following steps: identifying (1) the path segments for which the map needs to be prepared; for each path segment, calculating (3) primary autonomy reliability indices in accordance with at least two distinct autonomy functions; and calculating (4) for each path segment a
10 final autonomy reliability index on the basis of the primary autonomy reliability indices.
2. A method according to claim 1, wherein the final
autonomy reliability index is calculated by taking a
15 weighted average of the primary autonomy reliability indices.
3. A method according to claim 2, including the following
steps: performing a plurality of calculations (4) for
20 each final index with distinct weighting coefficients; comparing (5) the resulting final indices; and preparing (6) the navigation autonomy map by retaining the weighting for which the lowest final index is the highest of the lowest final indices of the various weightings.
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4. A method according to claim 2, including the following
steps: performing a plurality of calculations (4) for
each final index with distinct weighting coefficients;
comparing (5) the resulting final indices; and preparing
30 the navigation autonomy map by retaining the highest final index for each path segment.
5. A method according to claim 1, characterized in that
it includes the steps of identifying path segments for
35 which the final autonomy reliability indices are less than a predetermined threshold, and of performing a
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smoothing operation (7) applied to the immediately adjacent path segments.
6. A method according to claim 1, characterized in that 5 it includes a prior step of analyzing (1) the configuration of the path segments and of installing equipment adapted to improve the primary autonomy reliability indices.
10 7. A navigation autonomy map for a vehicle covering a zone comprising path segments, the map being characterized in that for each path segment it includes a final autonomy reliability index obtained by taking a weighted mean of primary autonomy reliability indices in
15 accordance with at least two distinct autonomy functions.
8. The application of an autonomy map according to claim
7 for determining a path, characterized in that autonomy
parameters are added to geographical parameters for
20 determining the path.
9. An autonomous vehicle including an automatic driver
unit and a navigation unit; the automatic driver unit
being connected to vehicle control members and to sensors
25 for detecting the behavior of the vehicle and the surroundings of the vehicle, and incorporating calculation means enabling the control members to be driven on the information supplied by the sensors so that the vehicle remains on a determined path in compliance
30 with traffic regulations; the navigation unit comprising a module for planning itineraries on the basis of map data comprising an autonomy map according to claim 7, the autonomy map being used both by the navigation unit to determine an itinerary as a function of the final indices
35 of the segments traveled, and also by the driver unit to determine which sensors should be given precedence on the basis of the segment traveled.
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