2013 年 6 巻 4 号 p. 172-176
An optimal G-shaped load cell was designed for measuring two ranges of loading. This G-shaped load cell had a mechanical point, by which a light or heavy load could be distinguished. In the shape optimization process, displacements at certain points were maximized without violating stress constraints. The coefficients of elliptical curve functions were treated as design variables. The mass of the load cell was reduced by 6.91 %. The slope of the stress response increased about 19.8 % which significantly improved the sensitivity of the load cell. A prototypical load cell was made. The relation between voltage and load was established with loads from 49 to 490 N. The maximum relative errors in light and heavy loadings estimation are 8.0 % and 1.36 %.