NGHIEN ClJfU-TRA0D6l XAC DINH VAN TOC THICH HOP KHI DO HAY DO NHANH TREN MAY DO TOA D O DANG CAU TRUC PGS.TS Thai Thi Thu Hd', ThS Pham Hong Thanh' 'TrUcfng Dai hpe Bdch khoa Tp Ho Chl Minh -TrUcfng Dai hpc Tran Dai Nghia To increase CMMs productivity, higher probing speeds ofCMMs are chosen Performing at higher probing speed results in increasing the dynamic errors and the vibration of CMMs and affects their accuracy For this reason we should specify reasonable CMMs velocity when probing at high speed This article presents the method specifying the reasonable speed of CMMs to eliminate the plastic deformation phenomenon ofworkpiece De tdng ndng sud't cua mdy tga do, gidi phdp dUdc lUa chgn Id d cdc van tdc cao hdn Khi tdng tdc do ddn den sai sd dpng lUc hgc cua mdy cung se tdng theo vd dnh hUdng khdng nhd den dp chinh xdc cua kit qud do, vi vdy hay dd nhanh cdn phdi xdc dinh tdc dp thich hdp Bdi bdo ndy trinh bdy cdeh xdc dinh van tdc hay dd thich hdp dUa tren cd sd hqn chi hien tUdng bien dang deo ciia be mat vat BO TRI VA P H A N T I C H Q U A TRINH DO, DO NHANH De thUe hien qud trinh ta ehon phuong va eham ciia dau vdi b l mat vat the theo phuong thing dUng (phuong song song v6i true Z) vd CO hu6ng tU tren xu6ng dUcfi Khi chpn nhU the, he thong se ciing viing hon, dong th6i ban chl hien tUpng vd biln dang cong cua kim la rat nho nen co t h i bo qua v^V^VV^SSSSSSS Hinh 1: Vi tri cua dau va vat t^i thOi diem X