The effects of internal and external heat generation on machine tools cause thermal deformation to lead to the reduction of machining accuracy. The internal heat generation on spindle, ball screws or motors has been studied and proposed the countermeasures in many reports. However, the heat generation by guiding is not studied enough so far. The demand for machining accuracy in machine tools are still getting higher, then we need to consider the effects of heat generation by guiding. In this study, using the 3-axis vertical type machining center that has the hybrid guiding system (with sliding and rolling elements), the temperature changes and the relative displacement between the spindle and the table are measured. By FEM based on the temperature change data, the thermal deformation is estimated. Then, the effects of heat generation by guiding are investigated and suggested the countermeasures on FEM. The results obtained in the study are as follows, (1) The simulation results based on the experimental data give close agreement with the experimental results. (2) Even if the heat generation of driving system can be suppressed, a certain level of relative displacement might be remained. In some cases, the relative displacement without the heat generation of the driving system is even greater than or equal to that with the heat generation. (3) The countermeasure that the effect of cooling of the guide rail or its circumference on the thermal deformations is simulated and the possibility that can decrease the thermal displacement is suggested.

The Swiss-type automatic lathe is designed to produce small-diameter and long rods with high accuracy and efficiency. However, its unique mechanism causes the disadvantage of a large amount of waste material. This disadvantage can be solved by the use of the friction welding method. Friction welding uses frictional heat generated by mechanical rotational energy and applies to automatic lathes with two opposing spindles and high-precision positioning functions. Friction welding is performed with a friction welding machine. This machine has a rigid mechanism for hydraulic pressure and pressure control. Therefore, there are some differences between friction welding machines and lathe configurations. In the research, the authors optimized the welding conditions on a Swiss-type lathe using tensile strength evaluation of joined workpieces as an index.

It is important to accurately inspect road pavement conditions for maintaining the safety and comfort of drivers. In recent years, Mobile Mapping System (MMS) mounted with a laser scanner has been widely used and pavement defect extraction using MMS point clouds is expected. This paper presents an extraction method of region-type defects such as rutting and potholes and line-type defects such as cracks of pavement surfaces using point clouds acquired by a Mobile Mapping System. The features of the proposed method compared with related works are the ability to extract displacements of the region and line-type defects using a single framework and the ability to extract defects with different scales and complex geometries. The proposed method first estimates an ideal pavement surface based on smooth curve fitting to scanlines using an index that represents the impact level of defects at each point. Then, vector data of region and line-type defects are extracted using displacements from the ideal pavement surface at each point. In the experiments, the proposed method achieved an IoU (Intersection over Union) of 80.2% for extracted regions and ground truth of region-type defects, and a recall of 90.7%, a precision of 97.0%, and an RMS of 10.0mm by Heipke's proposed method in the extraction of line-type defects.

Eyelid pressure distribution is visualized as a 2D chart of abrasive mark using a sucrose film coated contact lens and an image analysis system. The lens was attached in a rabbit eye for a short time from 1 to 2 min, and the abrasive mark can be observed by comparing two images taken before and after the experiment. The lens was fabricated by a lamination of a mold casted sucrose and a spin-coated PDMS lens. In order to minimize rabbit's stress caused by wearing the lens, as well as a shorter measurement time, experimental conditions are explored on tear volume for lens lubrication, waiting time before blink, number of blink and blink period. Finally, abrasive charts were obtained by manually assisted eye blink, and they are interpreted as a 2D eyelid pressure distribution chart. A maximum thickness decrease of 0.5mm has been obtained for a blink number of 20 and a blink period of 3s. Biocompatibility and health disorders due to the sucrose lens were also evaluated for 7 month, resulting in no health damages.