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Hi All, Trying to work out a universal way of getting the length of intersecting lines, easy when lines are level, but not so (for me) others. The image below shows a lifting lug, the angle of action can be 0 deg to 150 deg for example. I need to know the length of the lines from the red circle to the outline, individually, then I can see the shortest length, this must be for all angles, effectively tracing the intersection point through the angles. I know I can use Pythagoras, but was hoping to use something like GPC, but this works only for polygons? Lug Horizontal.sm (27kb) downloaded 12 time(s).
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Try a short circle code.
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Hi Jean,
I will have a look, I'm sure I can use something. Thanks
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ianlh, in your example it’s convenient to use the rotation matrix Lug Horizontal1.sm (19kb) downloaded 19 time(s).
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Whereas the system is built scalar wrt θ make it more convenient local at graph display. Lug Horizontal_2.sm (23kb) downloaded 13 time(s).
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This provides the shortest distance from the segments of the polygon to the circle. However, the distance isn't really to the segment but to a line through the endpoints of the segment. There is no test if the normal to the line through c is between the vertices of the segment. For the given geometry this works. For proof of strength this is only useful if a given force may act under any angle but the force doesn't depend on that angle. Lug Horizontal_Kr.sm (32kb) downloaded 12 time(s). |
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on 20/07/2020(UTC), on 21/07/2020(UTC)
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Hi. This is what's actually do the Ber'f function: But notice that for use matrix multiplication for translations you must to use homogeneous coords ( http://elopez.fime.uanl.mx/@materias/732/@Tema%203%20-%20Transformaciones%202D.pdf page 15) Best regards. Alvaro.
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2 users thanked Razonar for this useful post.
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on 21/07/2020(UTC), on 21/07/2020(UTC)
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Thank you, Razonar.Aapplying homogeneous coordinates helps automate the process. Variant with homogeneous coordinates Lug Horizontal3.sm (18kb) downloaded 12 time(s).Edited by user 21 July 2020 14:37:24(UTC)
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2 users thanked Ber7 for this useful post.
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on 21/07/2020(UTC), on 21/07/2020(UTC)
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2 users thanked Razonar for this useful post.
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on 21/07/2020(UTC), on 22/07/2020(UTC)
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2 users thanked Ber7 for this useful post.
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on 24/07/2020(UTC), on 25/07/2020(UTC)
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Hi Ber. That's not science, that's art. Maybe you can find this book interesting: Modern Robotics. At page 608 in the pdf, for example: The notation isn't the best, but it can be converted to a general Rotations and translations for the forward kinematics of a robot. Best regards. Alvaro.
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2 users thanked Razonar for this useful post.
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on 27/07/2020(UTC), on 27/07/2020(UTC)
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Hello Razonar. "Modern Robotics" book sparked my big interest. Thank you for the link.
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