Development of 3-Dimensional Scanning Probe Data Acquisition System Based on DSP
|School||Harbin Institute of Technology|
|Course||Instrument Science and Technology|
|Keywords||3-dimensional scanning probe data acquisition DSP USB|
The CNC gear measuring center with a wide measurement range, high resolution, and great efficiency is used widely in the field of gear measurement these years. The former data acquisition system which is slow and based on the ISA bus can not meets the need of the morden industry. So it is necessary to develop a high speed data acquisition system based on a more advanced interface technology.This paper gives an introduction to the work theory of the 3-d scanning probe. Then, the state of research and development of the probe is analyzed. The design and manufacture of the hardware and software in the data acquisition system are emphatically introduced. The following work has been done:(1)According to the characteristic of the output signal of the 3-d scanning probe, the hardware circuit of the system is designed and manufactured, including the signal-processing circuit based on the 3-d probe, the circuits of data acquisition and USB interface circuit. The isolation and filtration of the analog signal is completed in the signal-processing circuit; the data acquisition module, which is manipulated by the DSP, includes some functional circuits such as Analog-to-Digital converter ,the memory expansion ,electrify bootstrap and the reset circuit of DSP; the digital signal is transmitted through the USB interface.(2)Three sections of DSP program, USB device drive program and application program are included in software design of the data acquisition system. Firmware controls USB communication and data acquisition, USB device driver provides assurance for the communication between the system and PC, the application program is the interactive interface for users and the system.(3)The system’s stability and linearity experiments are carried out at the end. The results show that the system can transfer correctly, and is of high stability and reliability. The precision of system, which is within 1μm, meets the design requirement. The system has been used in the CNC gear measuring center.