초록 ▼

A system for guiding an autonomous or semi-autonomous vehicle through a field of operation having obstacles thereon to be avoided employs a memory for containing data which defines an array of grid cells which correspond to respective subfields in the field of operation of the vehicle. Each grid cel

A system for guiding an autonomous or semi-autonomous vehicle through a field of operation having obstacles thereon to be avoided employs a memory for containing data which defines an array of grid cells which correspond to respective subfields in the field of operation of the vehicle. Each grid cell in the memory contains a value which is indicative of the likelihood, or probability, that an obstacle is present in the respectively associated subfield. The values in the grid cells are incremented individually in response to each scan of the subfields, and precomputation and use of a look-up table avoids complex trigonometric functions. A further array of grid cells is fixed with respect to the vehicle form a conceptual active window which overlies the incremented grid cells. Thus, when the cells in the active window overly grid cell having values which are indicative of the presence of obstacles, the value therein is used as a multiplier of the precomputed vectorial values. The resulting plurality of vectorial values are summed vectorially in one embodiment of the invention to produce a virtual composite repulsive vector which is then summed vectorially with a target-directed vector for producing a resultant vector for guiding the vehicle. In an alternative embodiment, a plurality of vectors surrounding the vehicle are computed, each having a value corresponding to obstacle density. In such an embodiment, target location information is used to select between alternative directions of travel having low associated obstacle densities.

대표청구항 ▼

A method of operating a vehicle to avoid an obstacle in a field of operation, the method comprising the steps of: installing in a first memory first data defining a first array of first grid cells, each for holding data corresponding to a respective value, said first grid cells in said first array c

A method of operating a vehicle to avoid an obstacle in a field of operation, the method comprising the steps of: installing in a first memory first data defining a first array of first grid cells, each for holding data corresponding to a respective value, said first grid cells in said first array corresponding to respective predetermined subfields in the field of operation; scanning one of said subfields in the field of operation for determining the presence of an obstacle therein; incrementing said value in a first grid cell in said first array corresponding to said scanned one of said subfields in response to a signal responsive to said step of scanning indicating a likelihood that an obstacle is present in said scanned one of said subfields; defining a region of operation in the vicinity of the vehicle; and computing a plurality of vectorial values, each vectorial value being responsive to the location of each first grid cell in said first array within said defined region of operation, with respect to the location of the vehicle, and said values in said first grid cells.