Design And The Research Of Key Technology For Self-tracing Robot Vehicle

Self-tracing robot vehicle(or Automated Guided Vehicle,AGV for short)is originally appeared in USA,which is mainly used for carrying plant material in manufacturing and assembly process.With the Germany "Industry 4.0" and“Made in China 2025” promoted,machine replace humanis accelerated all around the world.AGV is key devices in manufacturing and logistics industry,which has been widely promoted and applied in many countries.The development of AGV at home and abroad was studied in this paper.The key technology of AGV was analyzedin-depth.The work pattern of auto-delivery was come true which can be called things to human in warehouse delivery for large scale E-commerce or material distribution inproduction line.Theexisting AGV cannot meet the specialrequirement for the diversification ofstructural types and functions.Based on practical situations,the content as follows was studied in this paper for different delivery and functions requirement.Firstly,the mechanical concept of AGV was designed.According to the requirement of general scheme,the body structure,lift structure and driving structure were designed for the AGV.The key mechanical structure of AGV was designed and calculated.The lead screw and gear motor of lift structure were analysed by calculation and checking in detail to insure stationarity of lifting.The driving structure of AGV was designed in detail according the actual working environment.The motion resistance calculation and parameter selection of driving motor were done.The suspension system of driving structure was designed in detail.Secondly,thekinematics modeling of AGV was done.The steering process of AGV was analysed based on characteristic of navigation.The suitabledifferential method was adopted in this paper.The mathematic model of electronic differential was obtained combine with the traveling track of AGV.The traveling track is detected by position sensor and gyroscope in order to improve trajectory accuracy.Thekinematics modeling of AGV was done based on process analysis of magnetic guidance.Thirdly,the control system of AGV was studied in-depth.The control method was analysed combined with conventional PID controlling.The double closed-loop PID was proposed basing on position control and angle control.Different control method was adopted respectively according to the result of position feedback and angle feedback.The recursive PID controller was used in position feedback to reduce computation.And the incremental PID controller was used in angle feedback.Under the precondition ofposition precision guarantee,the pre-controlling of the driving wheels was done based on angle feedback to improve the travelingprecision.And the overshootand settling time were decreased in position controlling as while.Last,the hardware design of control system was done based on the requirement.This section includes the scheme design of control system,selection of control unit,magnetic sensor,gyroscope,obstacle avoidance sensor and interface circuit design.And the wireless communication system was designed as while which include configuration control software,backend server,wireless AP and the interface circuit design of embedded PC.The key mechanical structure of AGV was designed in this paper.The kinematics modeling of AGV was done.The double closed-loop PID was proposed basing on position control and angle control to improve the traveling precision.And the overshoot and settling time were decreased in position controlling as while.The AGV has compact size and high navigation accuracy,which can be used in warehouse and factory logistic.