Electronic steering of a mobile robot for wall following and obstacle avoidance

Abstract

Abstract Robots, including mobile robots, provide many services in military, industrial and space applications. They shorten time, reduce expenses, and reduce danger to humans in places that may pose a threat to human life. Although the use of mobile robots in civil applications is few, it is in an increasing growth. Such as using it to transport goods in small neighbourhoods or to clean streets. Most of the algorithms in robot navigation are wall or path tracking through conventional sensors directly or through optical or physical sensors. Mobile robots are of different types, and these types depend on the number of wheels and the way they are distributed and directed to add to the robot the number of degrees of freedom. One of the problems facing the mobile robot is the multitasking of self-driving, such as tracking a path and discovering and avoiding an obstacle. Multi-tasking caused confusion for the mobile robot, as its processing of one task in tracking the wall makes it deal with the distance from the wall as a reference point to keep it in the alignment position regardless of the speed of its wheels or the angle of deviation of the wall from it. This process requires the provision of many additional data to enable it to perform the task. This research presents the design and construction of a mobile robot that tracks the wall, analyses the obstacles, and then takes action. The work is to build a mathematical model and calculate the mathematical effects on all the available information from the sensors measuring distance and freedom, speed and real time information. The idea entered on separating the robot programmatically into two parts. The first part is a mobile robot that has electronic guidance based on speed sensors connected to the front wheels, which are included as part of a closed control system to control the speed of the wheels accurately. At the end, this robot can walk straight for a distance that can be determined and implement deviations at a specific angle with the given value, as well as it can walk in the form of a square, triangle, and circular as well as it can walk on an inclined road up or down without decreasing or increasing its speed. This method makes the mobile robot more flexible. As for the second part, it is measuring the angle of deflection of the wall and exploring obstacles by measuring the distances surrounding the robot at an angle of 90 degrees. The deflection angle of the wall is calculated using an algorithm that depends on calculating the distance between two points within the path of the robot. These two points have information about the measured distance between the wall and the robot, the speed of the robot, and time. Through this information, the deflection angle of the wall is calculated relative to the mobile robot. The wheel speed control algorithms and the electronic steering algorithm were implemented on a processor connected to the wheel marketer and considered the first part, then algorithms were implemented to calculate the wall deviation measurement and analyse the obstacles and considered the second part. Information was exchanged between the two processors to carry out all the tasks, as the first processor provides information about the speed of the wheels and time, and through which the second processor can calculate all the distances that it wants to calculate as virtual points. The most important conclusions that emerged through practical experience are the effect of the distribution of sensors on the robot’s structure and the presence of a time difference in the wheels’ transition from one speed to another and even from a static state to a moving state, despite its being proven around the reference point, and this required solving it programmatically in equalizing this timing to ensure that the robot remains in Forward direction when changing its speed. The project has proven high accuracy with high information management.