Journal of the Japan Society for Precision Engineering
Online ISSN : 1882-675X
Print ISSN : 0912-0289
ISSN-L : 0912-0289
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Displaying 1-20 of 20 articles from this issue
Special Issue : The Forefront of Friction Joining Technology
Review
Lecture
My Experience in Precision Engineering
Gravure & Interview
Introduction to Precision Engineering
Introduction of Laboratories
 
Paper
  • Shota MATSUI, Jun MATSUNOSHITA, Nobutoshi OZAKI, Toshiki HIROGAKI, Eii ...
    2024 Volume 90 Issue 7 Pages 579-586
    Published: July 05, 2024
    Released on J-STAGE: July 05, 2024
    JOURNAL FREE ACCESS

    In this study, we focused on screw cutting with a thread mill tool based on helical interpolation motion and proposed a novel monitoring method to achieve a high accuracy of screw cutting with a wireless holder system. In this paper, the machining of screws with the same pitch and different nominal diameters using the same tool was investigated. In addition, the method of drilling a pre-hole and then thread cutting, and the method of drilling a pre-hole and then thread cutting at the same time were studied. As a result, it was found that when machining threads with the same pitch and different nominal diameters using the same thread mill, the cutting force during machining is almost the same by considering the feed rate of the table to be constant at the cutting point. In addition, it was found that the radius compensation was likely to be the same if the feed rate was kept constant at the cutting point during threading after pre-drilling. On the other hand, it is necessary to consider the amount of radius compensation for each nominal diameter when both pre-drilling and threading are performed at the same time.

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  • —Experimental Analysis of Causes of Nickel Adhesion on Rock Surface by Friction Tests—
    Katsushi FURUTANI, Ryota INUKAI, Tatsuaki OKADA, Kazuto SAIKI, Hiroyuk ...
    2024 Volume 90 Issue 7 Pages 587-593
    Published: July 05, 2024
    Released on J-STAGE: July 05, 2024
    JOURNAL FREE ACCESS

    This paper investigates causes of the nickel adhesion during wire-sawing of rock by friction tests. In future planetary or asteroid explorations, wire-sawing is a solution for machining method for in-situ inspection. The authors have developed a compact wire-sawing machine which can be installed in a vacuum chamber. Electroplated nickel fixing diamond grits on a core wire adhered on the bottom of machined groove on a rock during wire-sawing in vacuum with the wire-sawing machine. In the experiments, specimens were rubbed with a probe in air, vacuum or argon atmosphere. A nickel sphere and diamond tip were used for the probes. Basalt and nickel plates were used for the specimens. In the friction tests of basalt with the nickel sphere, the average friction coefficients in air was larger than that in vacuum. By the component analysis by EDX (energy dispersive X-ray spectrometry), oxygen was detected on the surface of the nickel sphere tested in air. The friction tests of nickel plate with the diamond tip were also carried out. Nickel debris with oxidation was observed on the whole track after the friction test in air. In particular, flakes of several tens of micrometers were observed on the boundaries of the track. It was suggested that nickel became brittle by the oxidation so that it was removed with the diamond grits due to fracture. Plastic flow of nickel and less oxygen was seldom observed on the surface tested in vacuum and in argon atmosphere. Since the basalt is harder than nickel, the nickel was scraped off by the friction and became debris at pores on the basalt. In vacuum, the debris adhered and accumulated on the basalt surface without oxidation. Then, the nickel layer formed. Low oxygen concentration in atmosphere greatly caused the decrease of the removal amount.

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  • Hironori MURAKAMI, Michio UNEDA, Ken-ichi ISHIKAWA
    2024 Volume 90 Issue 7 Pages 594-599
    Published: July 05, 2024
    Released on J-STAGE: July 05, 2024
    JOURNAL FREE ACCESS

    The evaluation of the beauty of Japanese swords relies upon the subjective sensibilities of experts; that is, this evaluation differs depending on the importance an expert places on the components of beauty. This study examined the Kansei evaluation of Japanese swords from the perspectives of both experts and novices. A virtual reality (VR) appreciation system was constructed to view Japanese swords housed in a museum and simulate holding them using a VR headset. After this viewing experience, a questionnaire was administered to novices and experts to compare their Kansei evaluation of Japanese swords. Multiple regression analysis and text mining were conducted to identify the components that influence this evaluation. This study determined that the Kansei evaluation of Japanese swords was influenced by the component of beauty, and the evaluation differed based on evaluators' experiential knowledge of Japanese swords. The experts in this study presented more negative opinions about VR systems compared with the novices, suggesting that skilled craftsmanship is not easily represented via VR.

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  • Takahiro SUZUKI, Manabu HASHIMOTO
    2024 Volume 90 Issue 7 Pages 600-606
    Published: July 05, 2024
    Released on J-STAGE: July 05, 2024
    JOURNAL FREE ACCESS

    Aiming to simplify assigning work of motion by humans to robots, we propose a method to determine robot assembly motion parameters of robot. They are determined using the optimal assembly motion parameters for a human as cues. However, there are physicality gaps between robots and humans. For example, in hand shape, a robot has two fingers, but a human has five fingers. Due to this gap, the optimal parameters differ between robots and humans. In this study, we define the difference in hand geometry between robots and humans as the physicality gap. Considering this physicality gap, the assembly motion parameters of robot are determined. The proposed method defines multiple features that take into account differences in hand geometry, and extracts these features from optimal assembly motion parameters for a human. Robot motion parameters with features similar to those features are determined. Experimental results using connecting rod showed that the success rate of the motion was 83.0%.

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