Research On Multi-DOF Coordination Control Of Automatic Loading Machine

As a basic raw material product,cement is widely used in large-scale infrastructure construction,farmland irrigation,energy transportation and real estate development projects.At present,most cement manufacturers have automated the bagging process of cement in the process of mass production of cement.However,in the process of bagged cement loading,most domestic cement companies adopt manual operation,which has a harsh working environment,high labor intensity and serious dust.In addition,the manual loading method also greatly affects the efficiency of cement production.In short,cement companies eagerly hope that the cement production bagging and loading can be carried out at the same time,and the technology upgrade is urgently needed.The thesis originated from the school-enterprise cooperation project,and researched on the control method of self-developed bagged cement automatic loader,aiming to solve the problem of high-precision and high-stability motion control of the automatic loader under high-speed and heavy-load conditions.The thesis mainly completed the following research work.Firstly,based on the overall design requirements of the automatic loader,the overall design of the control system was completed.According to the diversified status of domestic vehicle models and the specifications of bagged cement bags,a palletizing control plan for multiple placements and precise splicing along the width of the vehicle was proposed.The three-level control strategy of organization level,coordination level and execution level was adopted to achieve high adaptability and intelligent requirements for automatic loading.According to the requirements of the overall design indicators of the loading machine,through careful analysis and planning of the loading sequence,the optimized operating parameters of each motion mechanism were determined and a multi-agency coordination control mechanism was established.Due to the many operating mechanisms of the automatic loading machine,heavy load,high speed,high safety requirements,multiple control and detection nodes,high real-time information transmission and exchange,etc.,a dual MPU hardware system composed of high-end DSP and peripheral motion unit control and detection circuit were designed.Secondly,according to the established multiple placement and precise splicing control scheme,the research focused on the placement and splicing positioning control strategy composed of lateral moving mechanism and left and right moving mechanisms.The maximum running time allocated by the loading time sequence,for different working conditions,automatically establishes a real-time,dynamic speed trajectory control model,and cooperates with a precision displacement detection system to achieve dropping positioning control accuracy with an error of no more than±5mm.Finally,for the high-speed and heavy-load dropping movement mechanism and forward and backward movement mechanism,on the premise of meeting the maximum operating time assigned by the loading sequence,for different operating conditions,an asymmetric trapezoidal velocity control model was established in real time and automatically.Taking the smooth transition of running speed as the control target,an S-shaped speed control trajectory model was established in real time and automatically.Combined with the peripheral precision detection system and PID control model,the stability control of the heavy-load and high-speed motion mechanisms were realized.All the control schemes in the paper have undergone a lot of on-site debugging and experimental verification,and have achieved the expected design goals.At the same time,all the hardware and software design and debugging of the dual DSP control system have been completed.The automatic loading machine has initially reached the requirements for automatic loading.