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Aiming at the problems of low efficiency of the traditional method for detecting smooth plug gauges and poor repeat accuracy of measurement parameters, a measuring system for the diameter of a smooth plug gauge based on machine vision technology is designed. This system drives the work-piece to move by two-dimensional work platform and collects image data through CCD, and the diameter parameters of the smooth plug gauge are obtained by processing the image which uses the threshold neighborhood location and segmentation method. In this paper, the mechanical structure and control structure of the measuring system are designed, the measurement principle and calibration method are explained, the relationship between the diaphragm and the threshold value under a fixed light intensity, and the relationship between the light intensity and the threshold value under a fixed diaphragm are studied. Finally, experiments have verified that the measuring system can complete the measurement efficiently, automatically, and with high precision within 20 s, and the repeatability of the measurement does not exceed 1 μm.

In the process of screw thread manufacturing, the cooling liquid or lubricating oil will adhere to the screw thread surface, which affects the vision measurement results of the screw thread parameters. To simulate the adhesion behavior of oil on the thread surface during the actual measurement, four different attachment states were set in this experiment. An image measuring instrument was used to collect the screw thread images of different adhesion states. Then, the distribution of the oil film on the screw thread surface was analyzed with computer image processing. The visual inspection method was used to obtain the relative influence rate of the oil adhesion on the measurement result of the screw thread parameters. Finally, an experiment-based pitch diameter compensation method was proposed, and the compensation effect of this method was verified with the test method. Experiments showed that the effect of oil adhesion on the measurement results of the diameter parameters is greater than 7 µm, and the effect on the measurement result of the thread angle is greater than 0.1°. The compensation experiment showed that the compensation efficiency was above 70% for the pitch diameter.

Tremor is a rhythmic, involuntary oscillatory movement that severely affects some aspects of a patient's daily life. The use of wearable tremor-suppressing orthoses has become an effective, noninvasive treatment method for controlling tremors. This article summarizes recent developments in upper limb tremor suppression orthoses, aiming to provide a foundation for future research. By analyzing the working mechanisms, degrees-of-freedom (DOFs), weight, and tremor suppression effectiveness of various types of orthoses, the following conclusions are drawn: We found that differences in the working mechanism and the number of suppression directions are related to the weight of the device; weight, in turn, is a major factor affecting the comfort of the orthoses; and the combination of the number and weight of the damping direction affects the effect of the damping equipment. Balancing these three factors should be a key focus of future research. Moreover, researchers are placing greater emphasis on the comfort of the wearer during the development of these orthoses.