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- | ====== Three Flexure Cross Hinge ====== | ||
- | |||
- | A three flexure cross-hinge is an elastic joint which has a single rotational degree of freedom and consists of three seperate leafsprings. | ||
- | ---- | ||
- | ==== Description ==== | ||
- | |||
- | This example shows a static simulation of a three flexure cross hinge rotating from -30 degrees (initial rotation of -30 degrees) to +30 degrees rotation | ||
- | |||
- | Rotational motion is pre-described by adding three stacked hinge elements with orthogonal rotation axes (equivalent to a spherical joint) and pre-describing rotational motion around the z-axis (rotation in the degree of freedom of the flexure joint) with the '' | ||
- | < | ||
- | HINGE 17 12 36 1 0 0 | ||
- | HINGE 18 36 37 0 1 0 | ||
- | HINGE 19 37 38 0 0 1 | ||
- | FIX 38 | ||
- | RLSE 17 1 | ||
- | RLSE 18 1 | ||
- | INPUTE 19 1 | ||
- | </ | ||
- | The deformation of the pre-described hinge-element is specified in the second part of the dat-file which is positioned between the '' | ||
- | < | ||
- | end | ||
- | halt | ||
- | .... | ||
- | INPUTE 19 1 -0.523599 | ||
- | DELINPE 19 1 1.047198 | ||
- | ITERSTEP 25 50 0.0000005 1 3 50 | ||
- | .... | ||
- | end | ||
- | end | ||
- | </ | ||
- | In this part, the '' | ||
- | < | ||
- | ITERSTEP 25 50 0.0000005 1 3 50 | ||
- | </ | ||
- | Furthermore, | ||
- | < | ||
- | XM 11 1.000000 | ||
- | XM 12 0.001000 0.000000 0.000000 0.001000 0.000000 0.001000 | ||
- | </ | ||
- | |||
- | ==== Visualization of stress levels ==== | ||
- | {{ :stress.gif |}} | ||
- | |||
- | |||
- | ==== Vibration modes ==== | ||
- | First parasitic vibration mode (translational mode) at 44 Hz: | ||
- | {{ : | ||
- | Second parasitic vibration mode (translational mode) at 45 Hz: | ||
- | {{ : | ||
- | Thirth parasitic vibration mode (torsional mode) at 53Hz: | ||
- | {{ : | ||
- | Fourth parasitic vibration mode (out-of-plane bending mode)at 57Hz: | ||
- | {{ : | ||
- | Fifth parasitic vibration mode at (torsional mode) 90Hz: | ||
- | {{ : | ||
- | Sixth parasitic vibration mode at (internal mode at which the end-effector barely moves) 243Hz: | ||
- | {{ : | ||
- | |||
- | |||
- | |||
- | |||
- | ==== Dat-file ==== | ||
- | Note: this dat-file is created with a custom matlab script and releases in the beam-elements are programmatically choosen. Therefore, the selected released deformation modes in the leaf-springs migth be non-trival. | ||
- | < | ||
- | % INNER LEAFSPRING | ||
- | X 1 -0.078218 0.063089 0.000000 | ||
- | X 3 -0.039109 0.031545 0.000000 | ||
- | X 5 0.000000 0.000000 0.000000 | ||
- | X 7 0.039109 -0.031545 0.000000 | ||
- | X 9 0.078218 -0.063089 0.000000 | ||
- | BEAM 1 1 2 3 4 | ||
- | RLSE 1 3 5 | ||
- | DYNE 1 1 2 4 6 | ||
- | BEAM 2 3 4 5 6 | ||
- | DYNE 2 | ||
- | BEAM 3 5 6 7 8 | ||
- | RLSE 3 1 | ||
- | DYNE 3 2 3 4 5 6 | ||
- | BEAM 4 7 8 9 10 | ||
- | RLSE 4 4 6 | ||
- | DYNE 4 1 2 3 5 | ||
- | FIX 1 | ||
- | FIX 2 | ||
- | |||
- | % rigid body to connect leafsprings | ||
- | X 11 0.000000 0.000001 0.000000 | ||
- | BEAM 5 9 10 11 12 | ||
- | X 13 0.008331 -0.100144 0.000000 | ||
- | BEAM 6 13 14 11 12 | ||
- | |||
- | |||
- | % OUTER LEAFSPRING | ||
- | X 15 0.066718 0.075146 -0.023546 | ||
- | X 17 0.033359 0.037573 -0.023546 | ||
- | X 19 0.000000 0.000000 -0.023546 | ||
- | X 21 -0.033359 -0.037573 -0.023546 | ||
- | X 23 -0.066718 -0.075146 -0.023546 | ||
- | BEAM 7 15 16 17 18 | ||
- | RLSE 7 3 5 | ||
- | DYNE 7 1 2 4 6 | ||
- | BEAM 8 17 18 19 20 | ||
- | RLSE 8 2 | ||
- | DYNE 8 1 3 4 5 6 | ||
- | BEAM 9 19 20 21 22 | ||
- | DYNE 9 | ||
- | BEAM 10 21 22 23 24 | ||
- | RLSE 10 4 6 | ||
- | DYNE 10 1 2 3 5 | ||
- | FIX 15 | ||
- | FIX 16 | ||
- | |||
- | |||
- | % rigid body to connect leafsprings | ||
- | BEAM 11 23 24 11 12 | ||
- | |||
- | |||
- | % OUTER LEAFSPRING | ||
- | X 25 0.066718 0.075146 0.023546 | ||
- | X 27 0.033359 0.037573 0.023546 | ||
- | X 29 0.000000 0.000000 0.023546 | ||
- | X 31 -0.033359 -0.037573 0.023546 | ||
- | X 33 -0.066718 -0.075146 0.023546 | ||
- | BEAM 12 25 26 27 28 | ||
- | RLSE 12 2 5 | ||
- | DYNE 12 1 3 4 6 | ||
- | BEAM 13 27 28 29 30 | ||
- | DYNE 13 | ||
- | BEAM 14 29 30 31 32 | ||
- | DYNE 14 | ||
- | BEAM 15 31 32 33 34 | ||
- | RLSE 15 4 | ||
- | DYNE 15 1 2 3 5 6 | ||
- | FIX 25 | ||
- | FIX 26 | ||
- | |||
- | |||
- | % rigid body to connect leafsprings | ||
- | BEAM 16 33 34 11 12 | ||
- | |||
- | % Hinges to actuate joint | ||
- | HINGE 17 12 36 1 0 0 | ||
- | HINGE 18 36 37 0 1 0 | ||
- | HINGE 19 37 38 0 0 1 | ||
- | FIX 38 | ||
- | RLSE 17 1 | ||
- | RLSE 18 1 | ||
- | INPUTE 19 1 | ||
- | |||
- | % END-effector visualization | ||
- | X 39 -0.066718000000000 -0.075146000000000 0 | ||
- | RBEAM 20 9 10 39 | ||
- | |||
- | end | ||
- | halt | ||
- | |||
- | ESTIFF 1 6210306.302256 0.667169 0.410972 569.952912 0.000283 0.000283 | ||
- | EM 1 0.2321471642 0.0000213207 0.0000000154 0.0000213054 0 | ||
- | ESTIFF 2 6210306.302256 0.667169 0.410972 569.952912 0.000283 0.000283 | ||
- | EM 2 0.2321471642 0.0000213207 0.0000000154 0.0000213054 0 | ||
- | ESTIFF 3 6210306.302256 0.667169 0.410972 569.952912 0.000283 0.000283 | ||
- | EM 3 0.2321471642 0.0000213207 0.0000000154 0.0000213054 0 | ||
- | ESTIFF 4 6210306.302256 0.667169 0.410972 569.952912 0.000283 0.000283 | ||
- | EM 4 0.2321471642 0.0000213207 0.0000000154 0.0000213054 0 | ||
- | ESTIFF 7 2415385.254432 0.240182 0.159840 33.531976 0.000043 0.000043 | ||
- | EM 7 0.0902894012 0.0000012594 0.0000000060 0.0000012535 0 | ||
- | ESTIFF 8 2415385.254432 0.240182 0.159840 33.531976 0.000043 0.000043 | ||
- | EM 8 0.0902894012 0.0000012594 0.0000000060 0.0000012535 0 | ||
- | ESTIFF 9 2415385.254432 0.240182 0.159840 33.531976 0.000043 0.000043 | ||
- | EM 9 0.0902894012 0.0000012594 0.0000000060 0.0000012535 0 | ||
- | ESTIFF 10 2415385.254432 0.240182 0.159840 33.531976 0.000043 0.000043 | ||
- | EM 10 0.0902894012 0.0000012594 0.0000000060 0.0000012535 0 | ||
- | ESTIFF 12 2415385.254432 0.240182 0.159840 33.531976 0.000043 0.000043 | ||
- | EM 12 0.0902894012 0.0000012594 0.0000000060 0.0000012535 0 | ||
- | ESTIFF 13 2415385.254432 0.240182 0.159840 33.531976 0.000043 0.000043 | ||
- | EM 13 0.0902894012 0.0000012594 0.0000000060 0.0000012535 0 | ||
- | ESTIFF 14 2415385.254432 0.240182 0.159840 33.531976 0.000043 0.000043 | ||
- | EM 14 0.0902894012 0.0000012594 0.0000000060 0.0000012535 0 | ||
- | ESTIFF 15 2415385.254432 0.240182 0.159840 33.531976 0.000043 0.000043 | ||
- | EM 15 0.0902894012 0.0000012594 0.0000000060 0.0000012535 0 | ||
- | |||
- | |||
- | XM 11 1.000000 | ||
- | XM 12 0.001000 0.000000 0.000000 0.001000 0.000000 0.001000 | ||
- | INPUTE 19 1 -0.523599 | ||
- | DELINPE 19 1 1.047198 | ||
- | ITERSTEP 25 50 0.0000005 1 3 50 | ||
- | |||
- | end | ||
- | end | ||
- | |||
- | |||
- | |||
- | VISUALIZATION | ||
- | |||
- | BEAMPROPS 1 2 3 4 | ||
- | CROSSDIM 0.033186 0.000891 | ||
- | DONOTDRAW 5 | ||
- | DONOTDRAW 6 | ||
- | BEAMPROPS 7 8 9 10 | ||
- | CROSSDIM 0.012907 0.000891 | ||
- | DONOTDRAW 11 | ||
- | BEAMPROPS 12 13 14 15 | ||
- | CROSSDIM 0.012907 0.000891 | ||
- | DONOTDRAW 16 | ||
- | BEAMPROPS 20 | ||
- | CROSSDIM 0.01 0.06 | ||
- | </ | ||
- | |||
- | |||