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In this study, an existing superfinishing method used for polishing glass surfaces was refined using a five-joint closed-link compact robot with fixed abrasive grains. In previous studies, a voice coil motor was used to control the constant-pressure pressing force while maintaining the polishing force for a relatively short period. However, maintaining the polishing force for long periods is imperative for achieving a high-quality polished surface. Thus, in this study, a strain gauge load cell was adopted in addition to a conventional piezoelectric force sensor to maintain the polishing force for a long period. First, the amounts of DC drift of the piezoelectric force sensor and strain gauge type load cell were compared to confirm the necessity of signal processing as well as the compatibility of long-term force measurement and high-frequency vibration measurement by application. Further, a method was proposed in which the change in the pressing force was recorded from the connected sensor; when the pressing force fluctuated, chatter vibrations were determined to occur, and the pressing force was temporarily set to 0 N. This method could obtain a better polished surface than the proportional-integral-differential (PID) control, which simply controls the pressing force at a constant value. Finally, chatter vibrations could be determined by detecting high-frequency sounds using a sound level meter. Notably, a finely polished surface could be obtained. [ABSTRACT FROM AUTHOR]

This study aimed to establish an exposure method that can induce homogeneous lesions with minimal inter-individual variability. The distribution of lesions induced by bleomycin (BLM) administration was also analyzed. C57BL mice were intrabronchially administered 20 µL of BLM (3 mg/mL) using a bronchoscope in the left or right bronchus. The mice were sacrificed 14 days after administration, and their lungs were evaluated histopathologically. BLM-induced inflammatory lesions were widely observed in the lungs. In the left bronchus-treated group, lesions were uniformly observed throughout the lobe, and no individual differences were noted. Meanwhile, in the right bronchus-treated group, individual differences in the distribution of the pulmonary lesions were observed. The distribution of lesions differed among the four lobes of the right lung owing to their anatomical features. Administration into the left bronchus is recommended for highly homogeneous lung exposure and for establishing models that contribute to highly accurate toxicity and efficacy evaluations., Competing Interests: The authors have no competing interests to declare., (©2024 The Japanese Society of Toxicologic Pathology.)