LOCALISATION

Localisation of the Robots Environment

Localisation of the Robots Environment

Introduction

To control mobile robots in standalone mode, the main task is the task of determining the current position of the robot [1]. The main sensors in the robots are always odometers - sensors of the wheels.

But not enough to localize the robot's sensor readings of the wheels, due to the fact that the wheels tend to slip when the curvilinear motion [2]. To solve the problem of localization in curved movements use different sensors. The article deals with methods of localization, based on the use of vision systems (STZ).

Those robots developers who use the technical vision for localization, often used different artificial or natural markers (landmarks).

In this paper we show another way, a very simple, which is shown to be more stable because it uses not the individual parts of the image, where we found markers or landmarks, and integrated into the whole image, which guarantees against random errors.

Localisation Technique

Localization - is a universal example of a robotic perception. It is the task of determining where things are.Localization - one of the most common perception of problems in robotics, since knowledge of the whereabouts of the objects and the actor are the foundation of any successful physical interaction. For example, robots are related to the type of manipulators should have information about the location of objects they manipulate. A robot moving in space, to determine where they are to pave the way to the target location.[3]

There are three types of localization tasks with increasing difficulty. If the initial pose of the localized object is known, then the localization is reduced to the problem of tracking the trajectory. Task of tracking the trajectory characterized by a reduced uncertainty. More complicated is the task of global localization, in which the initial location of the object is completely unknown. Problems of global localization converted to trajectory tracking problem as soon as the localization of the object, but in the process of their decision as there are stages when the robot has to consider a wide range of uncertain conditions. Finally, the circumstances can play with the robot and there will be a cruel joke, "the kidnapping" (ie, the sudden disappearance) of the object that he was trying to locate. The problem of localization in such uncertain circumstances, is called the problem of kidnapping. The situation of abduction is often used to verify the reliability of the method of localization in extremely adverse conditions.

For simplicity, assume that the robot moves slowly on the plane and that he was given a precise map of the environment. The pose of the mobile robot is defined by two Cartesian coordinates with the values ??of x and y, and its angular direction with a value of 0, as shown in Figure a). (Note that the corresponding rates are excluded, therefore, this model is more cinematic, and not     dynamic.) If these three values ??will be ordered as a vector, then any particular state is determined by the relation xt = (x t, y t, 0 t) t.

Example of maps of the environment: a simplified kinematic model of mobile robot. The robot is shown as a circle with a ...