A method of mapping a physical environment using an occupancy grid containing a set of cells (g ij) associated with respective occupancy probabilities, said method comprising a step of measuring, using at least one distance estimation sensor, a potential position (μ) of an object in the physical environment, wherein the sensor provides, for the measured potential position (μ), a first coordinate (μ r) according to a first dimension and a second coordinate (μ σ) according to a second dimension in a coordinate system of the sensor having at least two dimensions; a step of identifying a segment representing a distribution interval of probable values relating to the measured potential position, which extends according to only one of the two dimensions of the coordinate system of the sensor, said probable values relate to the measured potential position (μ) being associated with probability values given by a probability density function (φ) that can be represented by a curve having an apex which corresponds to the measured potential position (μ), and, the identified segment penetrating a subset of potentially occupied cells (c i) of the occupancy grid, for each potentially occupied cell (c i) of said subset, a step of evaluating a probability of occupancy of said potentially occupied cell (c i) comprising: - a step of determining features of a segment portion (χi) included in said potentially occupied cell (c i), comprising a length of said segment portion; - a step of calculating the probability of occupancy of said potentially occupied cell as a function of the determined segment portion (χ i), and using the probability density function (φ), wherein an approximation of said probability of occupancy is performed by calculating the area of a rectangle, one of the dimensions corresponds to the length of the segment portion included in said potentially occupied cell, and the other dimension is an approximate probability value assigned to said potentially occupied cell. a step of identifying a segment representing a distribution interval of probable values relating to the measured potential position, which extends according to only one of the two dimensions of the coordinate system of the sensor, said probable values relate to the measured potential position (μ) being associated with probability values given by a probability density function (φ) that can be represented by a curve having an apex which corresponds to the measured potential position (μ), and, the identified segment penetrating a subset of potentially occupied cells (c i) of the occupancy grid, for each potentially occupied cell (c i) of said subset, a step of evaluating a probability of occupancy of said potentially occupied cell (c i) comprising: - a step of determining features of a segment portion (χi) included in said potentially occupied cell (c i), comprising a length of said segment portion; - a step of calculating the probability of occupancy of said potentially occupied cell as a function of the determined segment portion (χ i), and using the probability density function (φ), wherein an approximation of said probability of occupancy is performed by calculating the area of a rectangle, one of the dimensions corresponds to the length of the segment portion included in said potentially occupied cell, and the other dimension is an approximate probability value assigned to said potentially occupied cell. - a step of determining features of a segment portion (χi) included in said potentially occupied cell (c i), comprising a length of said segment portion; - a step of calculating the probability of occupancy of said potentially occupied cell as a function of the determined segment portion (χ i), and using the probability density function (φ), wherein an approximation of said probability of occupancy is performed by calculating the area of a rectangle, one of the dimensions corresponds to the length of the segment portion included in said potentially occupied cell, and the other dimension is an approximate probability value assigned to said potentially occupied cell.