Shahrood University of Technology Journal of Solid and Fluid Mechanics 2251-9475 10 1 2020 03 20 Analytical and numerical investigation of reaction forces in fixturing of the rigid workpiece with polyhedral geometry Analytical and numerical investigation of reaction forces in fixturing of the rigid workpiece with polyhedral geometry 17 29 1799 10.22044/jsfm.2020.8494.2925 FA H. Parvaz Faculty of Mechanical and Mechatronics Engineering, Shahrood University of Technology, Shahrood, Iran Journal Article 2019 05 25 Reaction forces are generated at the locating points of the machining fixture by application of the external forces. They are considered as one of the important input parameters in different stages of fixture design procedure; including fixture planning, unit design, and verification. In the present study, an agile tool is proposed for calculation of the reaction forces based on the minimum norm principle. For validation of the results, finite element analysis is performed in Abaqus® software on a rigid workpiece with polyhedral geometry. Reaction forces are calculated from the numerical analysis and compared to the theoretical predictions. The worst-case error value equal to 3.9% is obtained for the theoretical predictions of the normal-to-surface components of reaction forces in comparison to the numerical results. Theoretical predictions of the tangential components of reaction forces are not accurate which seems to be a shortcoming for the model; however, their effects are negligible by considering that the intensity of these forces are low in comparison to the normal components. Effects of the influence parameters including the coefficient of friction and intensity of the clamping forces are also investigated on the results. It was concluded that the theoretical predictions of the normal components of reaction forces agreed well to the numerical data and results that were published at the previous studies. Agreement between the theoretical predictions, results of the previous studies and the finite element results confirmed the accuracy of the suggested model in calculation of the reaction forces in fixturing of the polyhedral workpieces. Reaction forces are generated at the locating points of the machining fixture by application of the external forces. They are considered as one of the important input parameters in different stages of fixture design procedure; including fixture planning, unit design, and verification. In the present study, an agile tool is proposed for calculation of the reaction forces based on the minimum norm principle. For validation of the results, finite element analysis is performed in Abaqus® software on a rigid workpiece with polyhedral geometry. Reaction forces are calculated from the numerical analysis and compared to the theoretical predictions. The worst-case error value equal to 3.9% is obtained for the theoretical predictions of the normal-to-surface components of reaction forces in comparison to the numerical results. Theoretical predictions of the tangential components of reaction forces are not accurate which seems to be a shortcoming for the model; however, their effects are negligible by considering that the intensity of these forces are low in comparison to the normal components. Effects of the influence parameters including the coefficient of friction and intensity of the clamping forces are also investigated on the results. It was concluded that the theoretical predictions of the normal components of reaction forces agreed well to the numerical data and results that were published at the previous studies. Agreement between the theoretical predictions, results of the previous studies and the finite element results confirmed the accuracy of the suggested model in calculation of the reaction forces in fixturing of the polyhedral workpieces. https://jsfm.shahroodut.ac.ir/article_1799_809a901ad4d5b3e91800f68e2850fe97.pdf