Research And System Implementation On Surround Control Of Wheeled Mobile Robot

In recent years,with the development of control science and technology and related theories,the degree of intelligence of mobile robots has become higher and higher.Correspondingly,people's requirements for mobile robots to complete their tasks have also been improved.In addition to the hope that they can achieve basic assembly and finishing work,but also require that they can independently complete some of the more complex tasks,such as circumnavigation and surveillance,and so on.Therefore,the problem of encircling the targets has gradually attracted widespread attention from scholars at home and abroad.In order to study this problem,this paper based on the common smart car model,combined with the visual detection module,built a wheeled robotic encircling control system,which not only realizes the encirclement of stationary and slow moving targets,but also can be used as an intelligent platform for algorithm verification.This paper first briefly compares the different wheeled robots in life,determines the type of wheeled robot in this paper,that is,a four-wheeled robot.And then analyzing its kinematics model and analyzing the conditions required to drive the four wheeled robot to encircle the targets based on its kinematic model.At the same time,the implementation of the wheeled robot enveloping control system is determined from the overall perspective.In order to realize the encircling control of the target,we first need to perceive the information of the target.Taking into account the practicality and extensibility,this paper uses color-based visual detection technology to realize the real-time detection of the target,using the camera to capture the target's running status in real time.Then,according to the color information on the target,the pixel coordinates are obtained by selecting an appropriate threshold value,and then converted to the world coordinates by the affine transformation between the coordinate systems.At the same time,taking into account the recognition of the color characteristics is greatly influenced by the light intensity,a double-threshold detection method is used to improve the positioning accuracy.Then,according to the target and mission requirements of the wheeled robot enveloping control system,the hardware platform of the wheeled robot is built,and the corresponding hardware circuit and driver program are designed.And the constant speed operation of the wheeled robot is realized by the incremental PID control algorithm to ensure the stability and efficiency of the hardware platform.At the same time,the upper computer software control program has completed functions such as target recognition and positioning,control algorithm operation,stable communication between host computer and hardware platform,and so on.Finally,in order to verify the actual effect of the platform,two kinds of algorithms are used to achieve the encirclement of the stationary and slowly moving targets respectively based on the distance;At the same time,when the distance information is unavailable,the angle estimation algorithm is used to realize the encirclement of the target only by using the angle information.And then,in order to handle the surrounding control problem in complex environments,a self-guided wheeled robot navigation system based on visual SLAM is designed to realize the autonomous operation of the wheeled robot.Through this system,the wheeled robot can autonomously run in the vicinity of the target in a complex environment and then use the distance or angle bracketing control algorithm mentioned above to complete the encircling control mission.