Research And Implementation Of Automated Guided Vehicle(AGV) Vehicle-Mounted System Based On Landmarks

With the increase of manpower cost and the continuous improvement of the automation level,the Automated Guided Vehicle(AGV)has been widely used in automated logistics system.An integrated AGV warehousing logistics system consists of several parts: dispatching system,AGV control system and communication system.AGV as the system's actuator,reaches the appropriate location to complete the corresponding operation according to the task.In this paper,forklift AGV as the research object,which involves the positioning,path tracking of the problem,designed and implemented the corresponding vehicle system control program.First of all,this paper summarizes the common positioning and navigation methods in AGV,and introduces the AGV platform and vehiclemounted system used in this subject.The vehicle-mounted system is divided into several sub-modules,including the main control module,motion control module,landmark positioning module,and so on.And the corresponding software is developed based on the vehicle-mounted system hardware.Then,the positioning method based on the StarGazer infrared camera sensor and the artificial landmark,which is used in the path positioning module,is proposed to solve the positioning coordinates by processing the infrared image reflected by the passive artificial landmark.There are many types of deviations based on this method,and the corresponding error model and working model are established in this paper.According to the above model,an improved method of incremental landmark location is proposed.First of all,we arrange the least artificial landmarks under the corresponding error range.Then,an algorithm of incremental construction of landmark maps is proposed to replace the algorithm of the sensor itself to reduce the error of constructing the map.Finally,when artificial landmarks are located at the edge of the sensor,errors are reduced by fusing the artificial landmarks the sensor detects.By the method described above,the repeat positioning accuracy and the reliability of the positioning system are finally improved without the addition of an additional sensor.After obtaining the more accurate positioning data,AGV is to follow the corresponding path to reach the target location to complete the corresponding operation.In warehousing systems,We can use the ideal straight line or arc to represent the fixed path of AGV operation.In this paper,a kinematic model of AGV is established.A path tracking algorithm based on the reference corner is designed.It can track the desired straight line and circular path more accurately and reach the target point to achieve the required navigation accuracy.Finally,a series of experiments were carried out using the experimental platform,including the experiment of localization and the experiment of path tracking.The experimental results show that the improved positioning system based on StarGazer sensor and artificial landmarks is effective and improves the positioning accuracy and reliability.In this paper,the path tracking algorithm based on the reference corner can follow the desired path more accurately under the above-mentioned positioning system.At the same time,the algorithm is applied to other positioning systems,and the related experiments are also carried out and good tracking effects are achieved.