Apparatus for obstacle mapping in a vehicle, the apparatus comprising: a memory configured to store a location matrix and an obstacle matrix, each representative of an area around the vehicle; and a logical module configured to: receive a plurality of sensor signal datasets from a plurality of respective ultrasound sensors, each sensor signal dataset comprising at least one amplitude value having a respective at least one associated distance value; modify the location matrix by superposing each amplitude value of each sensor signal dataset on the location matrix at all locations representative of a possible obstacle location based on the associated respective distance value and a location of the respective ultrasound sensor; determine an initial shaped obstacle as a peak location corresponding to a maximum value in the location matrix; characterised in that the logical module is further configured to: determine a final shaped obstacle based on recursively determining locations in the location matrix around the initial shaped obstacle having a value within a predetermined threshold of the maximum value and expanding the initial shaped obstacle to include the determined locations; populate the obstacle matrix based on the final shaped obstacle; and after the final shaped obstacle has been determined, calculate a further location matrix not including at least some of the amplitude values in the sensor signal datasets which represented a possible obstacle location at the peak location, whereby to identify any remaining peaks in the further location matrix indicative of a further obstacle. a memory configured to store a location matrix and an obstacle matrix, each representative of an area around the vehicle; and a logical module configured to: receive a plurality of sensor signal datasets from a plurality of respective ultrasound sensors, each sensor signal dataset comprising at least one amplitude value having a respective at least one associated distance value; modify the location matrix by superposing each amplitude value of each sensor signal dataset on the location matrix at all locations representative of a possible obstacle location based on the associated respective distance value and a location of the respective ultrasound sensor; determine an initial shaped obstacle as a peak location corresponding to a maximum value in the location matrix; characterised in that the logical module is further configured to: determine a final shaped obstacle based on recursively determining locations in the location matrix around the initial shaped obstacle having a value within a predetermined threshold of the maximum value and expanding the initial shaped obstacle to include the determined locations; populate the obstacle matrix based on the final shaped obstacle; and after the final shaped obstacle has been determined, calculate a further location matrix not including at least some of the amplitude values in the sensor signal datasets which represented a possible obstacle location at the peak location, whereby to identify any remaining peaks in the further location matrix indicative of a further obstacle. receive a plurality of sensor signal datasets from a plurality of respective ultrasound sensors, each sensor signal dataset comprising at least one amplitude value having a respective at least one associated distance value; modify the location matrix by superposing each amplitude value of each sensor signal dataset on the location matrix at all locations representative of a possible obstacle location based on the associated respective distance value and a location of the respective ultrasound sensor; determine an initial shaped obstacle as a peak location corresponding to a maximum value in the location matrix; characterised in that the logical module is further configured to: determine a final shaped obstacle based on recursively determining locations in the location matrix around the initial shaped obstacle having a value within a predetermined threshold of the maximum value and expanding the initial shaped obstacle to include the determined locations; populate the obstacle matrix based on the final shaped obstacle; and after the final shaped obstacle has been determined, calculate a further location matrix not including at least some of the amplitude values in the sensor signal datasets which represented a possible obstacle location at the peak location, whereby to identify any remaining peaks in the further location matrix indicative of a further obstacle. determine a final shaped obstacle based on recursively determining locations in the location matrix around the initial shaped obstacle having a value within a predetermined threshold of the maximum value and expanding the initial shaped obstacle to include the determined locations; populate the obstacle matrix based on the final shaped obstacle; and after the final shaped obstacle has been determined, calculate a further location matrix not including at least some of the amplitude values in the sensor signal datasets which represented a possible obstacle location at the peak location, whereby to identify any remaining peaks in the further location matrix indicative of a further obstacle.