No. 7 Modular Machine Tool & Automatic Manufacturing Technique. Jul TH166 TG659 A

Transcript

1 No. 7 Modular Machine Tool & Automatic Manufacturing Technique Jul DOI /j. cnki. mmtamt * TH166 TG659 A Precision Modeling and Analysis of Fixture System of Tenon Machining enter Based on Theory of Multi-body System LIU Zhi-feng ZHAO Lin-zhong LI Ying SUN Guang-hui MA Lei ollege of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology Beijing hina Abstract According to the appearance that the machining error of tenon machining center which is produced during working process the main error source of the analysis is the fixture system. The fixture system of tenon machining center uses the bolt positioning which affects the assembly accuracy of the whole fixture system and results in a large machining error. In order to derive the error formula of the assembly model and establish the error model of the fixture systemaccording to the mechanical structure and the connection mode proposing the method w hich is based on multi-body system kinematics theory and homogeneous translation. According to the use of bolt positioning w hich causes fault during w orking process and considering the particularity of the fixture system proposing a method that improves scheme of the fixture system for improving the machining accuracy of tenon machining center and establishes error model w hich is used multi-body system kinematics theory. Key words fixture system assembly accuracy multi-body system homogeneous translation error model * 863 SS2012AA AE E - mail lzf@ bjut. edu. cn

2 L 0 j L 1 j L 2 j L 3 j 2 3 L 4 j L 5 j 0 0 L 6 j S V 10 cosβ 0 sinβ cosα - sinα 0 T p 2 0 sinα cosα 0 - sinβ 0 cosβ cosγ - sinγ 0 a sinγ cosγ b X Y Z c 1 - ε z ε y δ x ε z 1 - ε x δ y T pe 6 - ε y ε x 1 δ z cosθ y 0 sinθ y 0 0 cosθ x T s - sinθ z 0 0 sinθ x cosθ x 0 - sinθ y 0 cosθ y 0 cosθ z - sinθ z 0 x sinθ z cosθ z y z 1 - ε zi ε yi δ xi V ε zi 1 - ε xi δ T se yi i x y z θ L n V S 1 i ε yi ε xi 1 δ zi x θ y θ z 8 L n V LL n-1 v 2 L o V V 3 5 ~ 8a b c V S L o α β γ V S L n V S S v V x y z V S s θ x θ y θ z V 2 S X Y Z 1 2 3

3 x Δβ Δx Δα Δy 1 Δz T 01p z ] 1 - Δβ Δx ΔT 01s 1 - Δα Δy - Δβ Δα 1 Δz ] T 01s I 4 4 ΔT 01s I T 12p z ] Δβ Δx ΔT 12p 1 - Δα Δy 1 Δz T 12s I 4 4 ΔT 12s I 4 4 ] T 23p I 4 4 ΔT 23p I 4 4 cos - sin sin cos 0 0 T 23s ] Δβ Δx ΔT 23s 1 - Δα Δy - Δβ Δα 1 Δz T 34p ΔT z] 23p ] 1 - Δβ Δx 1 - Δα Δy 1 Δz ] T 34s I 4 4 ΔT 23s I T 45p z] Δβ Δx ΔT 45p 1 - Δα Δy 1 Δz u Δα Δy 1 - Δβ Δx 1 - Δα Δy 1 Δz - Δβ Δα 1 Δz 1 - Δβ Δx x Π T Lu w Lu-1 w p T ] Lu w Lu-1 w s X Δx u n Ln w o Y Δy Z Δy P t j Π T L j t L j-1 t pt L j ] -1 X Δα t L j-1 t s j n Ln t o Y Δβ u 1 Π T Lu w Lu-1 w p T Lu w Lu-1 w s P Z w u n Ln w o X Δx Y Δy Z Δz E u Π T ] Lu 6 Lu-1 6 w - j Π T ] X Δα Lj 0 Lj-1 0 t u n Ln 6 0 j n Ln 0 o Y Δβ T 01P ΔT 01P T 12P ΔT 12P T 23S ΔT 23S T 34P ΔT 34P T 45P ΔT 45P T 56P ΔT 56P Z x cos - sin 0 0 sin cos Δβ Δx x 1 - Δα Δy 1 Δz 1 - Δβ Δx 1 - Δα Δy 1 Δz 1 - Δβ Δx 1 - Δα Δy 1 Δz x 4 M ] T 45s I 4 4 ΔT 45s I 4 4 GB T 56p ΔT z ] Δβ Δx H12 56p 1 - Δα Δy 1 Δz ] H13 H14 H12 T 56s I 4 4 ΔT 56s I d d h M M P t ( p tx p ty p tz 1 ) T 9 M ( p wx p wy p wz 1 ) T j 1 Π T L j t L j-1 t p T L j ] t L j-1 t s P t j n Ln t o 11 13

4 X Δx Y Δy Δz X Δα Y Δβ Z X Δx Y Δy Z Δz X Δα Y Δβ Z X Δx Y Δy Z Δz X Δα Y Δβ Z X Δx Y Δy Z Δz X Δα Y Δβ Z E cos sin - sin cos cos + sin cos - sin cos + sin cos sin sin - cos cos + sin ] mm 0 90 X Δx Y Δy Z Δz X Δα Δx Δy Δz X Y 0. 5mm u Π 1 u n L n 5 0T L u 5 L u j Π 1 j n L n 0 ot L j 0 L j E ] - ] P t T 01P ΔT 01P T 12P ΔT 12P T 23S ΔT 23S T 34P ΔT 34P T 45P ΔT 45P x X Δβ Δx 1 - Δα Δy 1 Δz x 1 - Δβ Δx cos - sin Δα Δy sin cos Δz ] 1 - Δβ Δx 1 - Δα Δy - Δβ Δα 1 Δz x x 1 - Δβ Δx 1 - Δα Δy 1 Δz 1 - Δβ Δx 1 - Δα Δy 1 Δz Y Δβ Z Δx Δy Z Δz X Δα Y Δβ Z Δx Y Δy Δz X Δα Y Δβ Z

5 126 7 X Δx Y Δy Z Δz X Δα Y Δβ Z X Δx Y Δy Z Δz J X Δα Y Δβ J. Z J cos - sin cos - sin sin cos cos + sin E J J J J Δx Δy Δz J mm 9. J Su ShipingLi Shengyi. A study on Prediction Modeling of Machining Accuracy for N Machine ToolsJ. IPN' He X Yung N H. orner detector based on global an-d local curvature properties J. Optical Engineering Moravec Harris J Zhang X H Lei M Yang D et al. Multi-scale curvature scale 2Harris Stephens M. A combined corner and edge detect-or spacej. Pattern Recognition Letters In Alvey Vision onferencemanchesteruk Smith S Brady M. SUSAN-A new approach to low-level image processing J. International Journal of omputer Vision 9Sheu H T Hu W. Multiprimitive segmentation of plan-ar D curves-a two-level breakpoint classification and tuning a- 4. pproach J. IEEE Transactions on Pattern Analysis and J Machine Intelligence Mokhtarion F Suomela R J. Robust image corner detection t- 10. hrough curvature scale space J. IEEE. Transactions on Pattern Analysis and Machine Intelligence J