The Automatic Control System Research And Development Of Falling Object Protective Test-bed Of Earth-machinery

Since Earth-machinery is widely used in a variety of construction occasions, it also appeared various forms of falling objects damage and various overturned accidents. Not only caused personal injury, but also caused huge losses to people's property, therefore top protection devices of Earth-machinery cab are more and more concerned, Test-bed based on testing the falling object protection devices has emerged at home and abroad. This paper aimed at reconstruction project for Falling Object Protective Test-bed of Earth-machinery in our shool, reforming design to its control mode, in order to achieve accurate automatic control for drop hammer up and down in the process of test-bed detection.Aimed at this Test-bed in our school, currently its work efficiency of manual control mode,accuracy for drop hammer up and down and safety performance do not really meet the test requirements,But also seriously fall behind the pace of development of the present mechanical testing technology and automatic control technology. Through vector control methods are used in Test-bed drop hammer elevator mechanism, establishing a simulation model based on Vector control mathematical model in Matlab 6.5,and analysising the simulation results.According to its performance of speed regulation, efficiency and energy consumption etc, determining that vector control algorithm can completely satisfy the requirements for Test-bed drop hammer lifting mechanism frequency conversion speed regulation and also can meet the precise requirements of height and location for drop hammer.This article takes computer as the control center,according to the text of the vector variable speed system design and the moving machinery FOPS test bed automation system's overall design, Using of modular programming process, the use of automatic control system as a whole prepared VB language software. The computer and the frequency changer carry on the communication using the serial port, the photoelectricity encoder may transform highly as the system feedback equipment the electric motor rotational speed and the drop hammer the corresponding pulse signal,the PCI-8333 data acquisition card gathering photoelectricity encoder pulse signal, however evacuation to computer. After carried on by the computer, the data passing through the dynamic link storehouse control algorithm operation, connects the R485/R232 transformation connection through the computer and the frequency changer,will operate after the numerical control quantity to deliver to the frequency changer, will control the frequency changer the movement frequency,thus will realize to the electric motor frequency conversion velocity modulation. This implementation of the automatic control of the tester requests in our school,completing the objectives for the reconstruction of.