Some questions relating to the construction of a digital instrument for the complex monitoring of gear wheels and transmissions

Conclusions The method of interpreting the discrete values of the kinematic error here developed has enabled us to realize a digital system based on unified functional elements for measuring and recording the kinematic, local kinematic, and cyclic errors for complete automation of the measuring process.The proposed error-calculation algorithm and accumulated experience in the complex testing of gear wheels and transmission provides genuine prerequisites for the development of improved complex-testing digital instruments based on the block-module principle of construction involving the use of integrated circuits.Translated from Izmeritel'naya Tekhnika, No. 2, pp. 61–63, February, 1976.     

Classification of digital measuring instruments

Summary A classification schematic of digital instruments (Fig. 2) based on the above article includes the classification of digitizers by their method of comparing the unknown and known quantities, by the method used in measuring by their equipment and their output devices, that is, their method of presenting the results.The examination of the design principles of digital instruments only with respect to these classifications shows a considerable variety of measuring methods for which these instruments can be used. It should be noted, however, that the above classification does not include many derived types of digital circuits. However, digital instruments based on intermediate types may be of great importance. Thus, for instance, the simultaneous utilization of digitizers and analogue instruments, which is characteristic for differential methods of measuring the difference between a discrete and an unknown analogue quantity, is employed in a considerable number of instruments [5,7]. In the category of intermediate types of digital instruments should also be included partly automatic instruments which comprise contact and contactless elements, digitizers based on the simultaneous utilization of different methods of comparing the unknown and known quantities, etc.The proposed classification of digital instruments is undoubtedly not the only possible one. However, in our opinion, it covers the basic principles for designing digital instruments and indicates certain possible tendencies in their development.In conclusion the author considers it his duty to express his gratitude to Corresponding Member of the Academy of Sciences, USSR K. B. Karandeev and to Prof. M. I. Levin for their valuable advice, as well as to candidate of technical sciences B. S. Sinitsyn and engineers B. V. Karpyuka and A. N. Kasperovich for the useful observations made by them in discussing the material dealt with in this article.     

Design principles of frequency multipliers for digital frequency-measuring instruments

Conclusions It will be seen from this review of various methods for multiplying frequency that, in addition to the generally known multipliers which use functional conversion of the input signal, there can also be designed multiplying devices, based on level quantization, on shifting of signals with respect to their phase or time, and on balancing.It should be noted that the output signal of the first group of multipliers has the same shape as their output signal. The frequency multiplication process in devices of the second and third groups can be accompanied by a transformation of the signal shape.The application of a given type of multiplier in digital frequency-measuring instruments depends basically on the maximum permissible variation of the transducer's output frequency. Thus, in transducers with a small deviation it is, probably, advisable to use frequency multipliers of the first group. It is obvious that balancing multipliers whose comparison element consists of a reversible counter are predominantly suitable for transducers with a large frequency deviation.The problem of obtaining the required frequency multiplier characteristics, consisting of their speed of operation and precision, requires a detailed investigation.Translated from Izmeritel'naya Tekhnika, No. 1, pp. 52–55, January, 1967.     

Error in balancing digital tracking instruments

Conclusions The balancing error distribution inside the insensitivity range of the null detector of discrete tracking systems is of a nonuniform rectangular-step type, and this must be taken into account in determining the probability characteristics of discrete tracking systems.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 59–61, April, 1971.     

基于特征检测的数字仪表数码快速识别算法

为对数显类仪表的显示数据进行自动识别与监测,提高该类仪表的自动化水平,需要研究仪表数码快速识别算法。该文提出一种基于特征提取的数字仪表数码快速直接识别算法。将图像进行预处理后,对数显屏幕进行定位。通过列切实现单个数码字符切割,对单个数码字符进行七段特征检测和五线相交检测,实现对正体数码和斜体数码的快速直接识别。实验表明,算法基本可以满足各种仪表数码的识别需求,识别速度快、准度高。