The Automatic Measurement System For Plumb-line

The cause of the dam failures is mostly because that the design is unscientific or there was deficiency during construction stage or lack of proper management in operation. Once a dam breaks,at best,wasting a lot of resources, at worst, endangering the downstream people’s life and property safety, resulting in the tragedy of the city flooded. These events also remind us of the importance of real-time detection of dam safety.Through real-time monitor,we can detect the potential dangerous in time,and make the remedial measures.If the dam deformation beyond the controllable range, we can also transform early.The automatic measurement system for Plumb-line’s main purpose is to measure the displacement of pendulum, in order to prevent the risk of dam deformation.This system takes a self-made parallel light source as the excitation source, an linear CCD as image sensor,STM32F107as the control core, and a TFT touch LCD screen as human-computer interaction platform. The main working principle is that:The parallel light projet the plumb-line to the CCD.The part of CCD blocked by the plumb-line will form a shadow.CCD convert the image and output the corresponding analog signal.Through collection and calculation, we can find out the exact displacement of dam Plumb-line.System hardware consists of six parts:light source circuit, CCD driver circuit, signal disposal circuit, AD acquisition circuit,LCD display circuit and communication module. Constant-current drives the light source to generate parallel light.Then CCD converted optical signal to analog voltage signal. After a conditioning circuit,the signal will be converted to be the range which can be collected by ADC.Then ADC transfers the data to STM32.Through the data filtering and processing,we can obtain the results. Then STM32can storage, display,or other data manipulation.The system hardware adopts uC/OS-II as operating system and transplant the FAT32file system uC/OS-II assign tasks to these modules.RS485Interface upload data to the dam monitoring room which realised timing automatic monitoring.At the base of system software and hardware,we tested the whole system.The system not only meet functional requirements and technical indicators,but also demonstrate good measurement accuracy and stability.