Long Term Monitoring of Bridges Using a Robotic Tacheometry System

Field-testing is an important topic in the validation of new infrastructure as well as in the assessment of obsolete and defi cient infrastructure. There is a need for accurate and inexpensive diagnostics methods that enable the prediction of the actual load carrying capacity of bridges through load testing. A major diffi culty in testing bridges is the measurement of vertical defl ections. The use of instruments such as mechanical dial gauges, linear potentiometers, and linear variable differential transducers (LVDTs) is usually not feasible. Access under a bridge structure is usually limited, which requires erecting temporary supports to mount the measurement instruments to the ground. These diffi culties can be eliminated by using a Robotic Tacheometry System (RTS) (Total Station), which offers the capability to measure the spatial coordinates of discrete points on a bridge without having to touch the structure.