Development Of The Tramcar Speed Measuring And Recording System Based On USB

Because of being short of effective intendance, the engine in coal mines often brings security accident due to excessive speed. It's an effective way to solve the problem how to watch tramcar speed under the mine by developing the tramcar-speed-measuring-and-recording system. This system band together tramcar speed measurement, over-speed alarm and the conservation, display and management of record data. Data is transferred depending on Universal Serial Bus equipment. Through the usage of this system, not only chauffeurs' excessive speed can be limited, also management can be made easily.The system is made up of two parts: measuring instrument under the mine and the computer on the ground. Taking the incremental photoelectric encoder as the sensor and based on measuring frequency, the measuring instrument use the singlechip to collect and manage speed impulse signals, and save needed speed and time data into the temporary card. Meanwhile, real-time tramcar speed or system time are displayed on the light-emitting diode. If the tramcar runs over speed, then an alarm is given. The incremental photoelectric encoder is fit for the environment full of powder and dust and strong noise. Also, it can be fixed expediently. It accords with the fact of tramcars' running to use the method of frequency measurement. Just before being off duty, the chauffeur inserts USB instrument into the special interface of measuring instrument, then work data are passed into USB instrument from the temporary card automatically. USB instrument is brought to the ground and inserted into USB interface of the computer while chauffeurs ascend to the ground. The special computer software will show up one shift's speed data in a table, which also has the ability of printing and inquiring. It has high data-transferring speed, the ability of Play and Plug and is convenient. The hardware design (including measuring instrument circuit and the inside and periphery circuit of USB module) and embedded USB host software exploitation are emphasized in this paper.