Research On Application Of Direct Drive Technology For Gear Measuring Center

Gear Measuring Center is a kind of numerical control instrument which is used for measuring all the parameters of gear. Harbin Jingda Measuring Instruments Company presents the most advanced technology of this area in China. To improve the performance, develop new style instrument and follow foreign advanced technology, direct drive technology must be used to the servo system of Gear Measuring Center. Direct drive technology brings servo system zero maintenance, clean mechanical assembly, improved accuracy, higher throughput, better reliability, and smooth, quiet operation.Tsinghua University and Harbin Jingda Measuring Instruments Company cooperate on the project which comes from Innovation Fund for Small Technology-based Firms. The dissertation designed direct drive servo system for Gear Measuring Center, improved the performance of the numerical control system, made foundation for developing new style instruments which can measure much larger gears and achieve higher precision.First, the dissertation analyzed the construction and control performance of existing instrument, presented the general planning based on direct drive technology, used DDL motor on the linear axis to erase the error of transmission chain and increase measuring precision, used DDR motor on the rotary axis to increase the feasible system load and improve the low-speed performance. Second, the dissertation made some research on the principle and application of servo controller, programmed programs running on the controller and a function library for accessing the controller, presented a method for accessing PCI device in DOS system. Third, the dissertation designed and developed the direct drive servo system, analyzed the control algorithm in servo driver, identified the system parameters, established the mathematical model of DDL and DDR servo system and made system simulation. At last, the dissertation did experiment to get the actual control performance such as control precision and following error, analyzed the influence of every parameter tothe control system, stated the final control performance, and presented two methods that keep system stability on the long-range variation of the system load.Direct drive technology has been successfully used on JD45 Gear Measuring Center. It increased the measuring precision, reduced the distance to foreign similar products.