Method for localisation and mapping of pedestrians or robots or humans in wheelchairs using wireless access points comprising the following steps: taking received Wireless Signal Strength measurements and/or time delay measurements from one or more wireless access points at regular or irregular time instances by a device carried by the pedestrian or robot - providing odometry measurements, such as human step measurements, human pedestrian dead-reckoning, robot or wheelchair wheel counter measurements, robot motor or wheelchair motor control inputs, from an odometry system to be carried or worn by or attached to the pedestrian, robot or wheelchair, and - providing a particle filter which has a particle population that, for each particle, comprises the pedestrian, robot or wheelchair location history, - wherein at each time-step of the particle filter each particle of the particle filter is weighted and/or propagated according to the odometry measurements and weighted and/or propagated according to the RSS and/or time measurement, and - wherein the location of the pedestrian, robot or wheelchair is extracted from the particle population, characterized in that - the particle population comprises for each particle the location probability distribution of the one or more wireless access points, wherein - at each time-step of the particle filter the location probability distribution of the one or more wireless access points for each particle is updated according to the RSS and/or time measurement and the previous location probability distribution of that particle. taking received Wireless Signal Strength measurements and/or time delay measurements from one or more wireless access points at regular or irregular time instances by a device carried by the pedestrian or robot - providing odometry measurements, such as human step measurements, human pedestrian dead-reckoning, robot or wheelchair wheel counter measurements, robot motor or wheelchair motor control inputs, from an odometry system to be carried or worn by or attached to the pedestrian, robot or wheelchair, and - providing a particle filter which has a particle population that, for each particle, comprises the pedestrian, robot or wheelchair location history, - wherein at each time-step of the particle filter each particle of the particle filter is weighted and/or propagated according to the odometry measurements and weighted and/or propagated according to the RSS and/or time measurement, and - wherein the location of the pedestrian, robot or wheelchair is extracted from the particle population, - the particle population comprises for each particle the location probability distribution of the one or more wireless access points, wherein - at each time-step of the particle filter the location probability distribution of the one or more wireless access points for each particle is updated according to the RSS and/or time measurement and the previous location probability distribution of that particle. - at each time-step of the particle filter the location probability distribution of the one or more wireless access points for each particle is updated according to the RSS and/or time measurement and the previous location probability distribution of that particle.