The Automatic Track Dolly Surveying The Distortion Of Guide Rail

The Guide Rail will gradually deform in axial and radial direction because of some factors such as constant heavy pressure, and ground subsidence. It will be troublesome or even dangerous if the deformation was out of some range. So it is necessary to check up the deformation timely. And it is recommended to give some maintenance if necessary. But we know that the rail guide is on the top of the workshop, it's not convenient to do the checkup by manpower. So we design the system to complete the work instead of people.The system mainly aims to survey distortion degree of guide rail. It can complete two degree freedom spin of the prism with high accuracy along with the transposition of the track dolly which moves on the guide rail. The prism serve as light reflection installment .In order to survey the distortion degree of the guide rail , the Electronic Total Station sends out the light beam to the prism then it will receive the same light beam which is reflected by prism , by the time difference it can determine the dolly position in the three dimensional coordinates. The track dolly is driven by DC motor. We can control the spin speed of dc motor by change the voltage on the motor armature, therefore the dolly can transfer its position along the checked track by various speed. For the precise spin angle ,we must know the realtime position of dolly, so the spin decode sensor is installed on the spin wheel, it is 500 pulse signal each revolution of the wheel, but the pulse signal frequency is double by 4 when it is passed to LF2407 DSP. As a result the DSP can require the dolly position information with error less than 1 mm. Prism is driven by stepping motor. In this system I apply Micro-stepping Driver for Stepping Motor to modulate the spin speed of the prism. This technique can greatly improve loading capacity, and increase the system stability .So as to transmit instruction to track dolly which is on the guide rail, I design the wireless transmission module. It is composed of nrf401 which is a true single chip UHF transceiver designed to operate in the 433MHz ISM frequency band. It features Frequency Shift modulation and demodulation capability.The completion of the system greatly increase the accurateness and safety of the check work that is done by manpower in the former time.