A microcomputer-based forecasring technique for compensating leadscrew drive kine-matic errors by the DDS(Dynamic Data Systems)approach is proposed in this paper, The kinematic error of a particular leadscrew drive system was described by an ARMA(16，15) model. In order to facilitate on-line compensation, an AR (9) model was fit instead of the ARMA model, Both models revealed the same dominate error components and have similar spectral plots, Experiments were conducted on a Giddings & Lewis Model IOV Numericen. ter. The re-suits show that the cumulative pitch error can be reduced some 80 to 90% through compen-satlon at lower feedrates of the table and about 50% at the higher feedrates using the forecasring technique.

A practical way to achieve machine tool drive system accuraey is througn corn-pensation in the position control loop. various strategies have been deueloped inwhich the compensation data are stored either in a'computer or by aiternattve techniques. The approach described in thispaper demonstrates how the dominant causes of the inaccuracies in machine tool drive systems cart be determlned in a simple and straightforward manner and how the compensation ta can be generated using a microprocessor-based calibration technique. The proposed method was demonstrated On a Giddings & Lewis Mode, 10V Numericenter and consists of three major steps: accura measurement, 21 error-map represen-tation, and3、error-mmap analysis anderror cause diagnosis. Accuracy measurement was accomplished by reading both the resolver counts and the output of a laser interferometer which serifedas a reference (master) scale. The heprocedure is basea on a strategy in which smal, 0.5mm(0.020 in.), highly accurate±2.5 tan (4±0.0001 in.)linear displacements ofthe machine tool table motion are taken as the measurement reference. An ARMA (Autoregressive Moving Average) model of order (16,/5) isthestatistically adequatemode, thatfitthedata of the Pangular displacement of theresolver. TheDynamicDataSystem techniquewasused, this purpose and it can also be used to represent the error-map function. A spectral analysis of the ARMA model revealed the sources of the kinematic errors

Conventional CNC circular interpolation algorithms are based on interpolating the next value according to the present value, regardless of the particular pulse increment method or data sampling method. In this paper, a new theory and algorithm for any space circular interpolation in a CNC system, called three-point recursion interpolation (TPRI) is proposed, which makes a breakthrough from the conventional interpolation algorithms and which is based on a two-step recursion scheme. The proposed algorithm improves not only the interpolation accuracy, but also the interpolation process, which is carried out by the recursion method based on initial values. The interpolation is easily done by the operations of adding and bit shift without multiplication or division. Thus, compared with the existing space circular interpolation methods, by means of the new algorithm, the computing size is remarkably decreased and the calculation speed is increased greatly, SO that the interpolation process may be enhanced strongly. The interpola-tion step is selected according to the tolerance of a segment of a circle. Also, the interpolation stability of this recursion algorithm is proven and the interpolation error and theoretical machining error are estimated in this paper.

本文根据数据拟合曲线的外延特性和勒让德多项式的正交性，提出了离散勒让德多项式序列（Discrete Legendre P0lynomial series，简记为DLPs，以下同）预报控制原理，给出了DLPs的一系列性质和实时在线递推预报算法，其计算量远远小于已有各种方法，解决了预报控制的实时性问题。经实验和生产现场验证，这一预报原理与算法具有很好的控制效果。

介绍了利用国产化设备实现胶鞋大底模具计算机辅助设计/计算机辅助制造一体化技术。采用直线和圆弧作为基本元素进行计算机辅助设计胶鞋模具，几何信息可直按应用来进行数控加工。两级计算机间采用直接通讯而无需纸带，磁带等中介物，这一实用的工业技术，将可解决大部分胶鞋大底模具生产的自动化问题。