A precision stopping measurement device for data acquisition of urban trains

Precision stopping of an urban train at a station is prerequisite before starting revenue service due to screen doors. Regulation for precision stopping of the urban train requires ±30 cm in general in Korea. Since there is no device to detect stopping error automatically, it takes long time to gather stopping error data at each station due to manual measurement using a ruler. In this paper, we present a principle and design of a precision stopping measurement device (PSMD) which can be easily used for error detection of precision stopping of urban trains. The PSMD developed in our laboratory uses a non-contact optical laser sensor installed at the platform to generate pulse signals from vertical black and white patterns attached on a train side. The number of the generated pulses is counted using a microcontroller, and then is sent to a notebook computer on the train via wireless RF communication. The performance of the PSMD is tested at the lab experimentally under indoor and outdoor environments.