Long range measurements using a contactless low cost optical sensor

Length measurement is very common in many industrial applications and there is a number of instrumentation involved, mainly dependent on the range and accuracy requirements. In this work, a contactless optical measurement unit is developed. It is based on a mouse sensor and an external laser source. The system is calibrated using an optical board and an electronic distance measuring system. Accuracy and precision of the system is evaluated using the reference data from a total station. Values of 1 mm and 0.3 mm are respectively obtained. Length range during the experiment is 8.5 m. The data of the optical measurement unit are compared with those obtained from a commonly used wheel encoder. Results from the optical sensor of the mouse improve the encoder data.