Timeline for Untangling entwined rigid chains in 3-space
Current License: CC BY-SA 3.0
8 events
| when toggle format | what | by | license | comment | |
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| Aug 25, 2017 at 11:38 | history | edited | Joseph O'Rourke | CC BY-SA 3.0 |
Image links broken; now fixed.
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| Feb 24, 2013 at 21:52 | answer | added | Michael Biro | timeline score: 2 | |
| Feb 24, 2013 at 21:05 | comment | added | Joseph O'Rourke | @Günter: I corrected to rotation about an axis---Thanks! Yes, originally I started to think about mixing translation & rotation. That is more natural, but I tried to simplify. Excellent point about motions in a strip. Thanks for these insights! | |
| Feb 24, 2013 at 21:02 | history | edited | Joseph O'Rourke | CC BY-SA 3.0 |
Correction by Guenter.
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| Feb 24, 2013 at 19:51 | comment | added | Günter Rote | Anyway, When you specify the steps in this form, another important 3-dimensional class of motions is excluded: screw motions (rotation around an axis with simultaneous translation along that axis). Of course such a motion can be approximated by a sequence of translations and rotations, but the number of steps might be large (not bounded in $n$). I imagine two chains that require a screw motion at one point. It would be analogous to allowing a point in the plane to move only vertically or horizontally. The necessary number of such steps inside a slanted strip can be as large as we like. | |
| Feb 24, 2013 at 19:48 | comment | added | Günter Rote | "rotation about a fixed point" is maybe inappropriate if 3d. It might be rotation about a fixed axis. | |
| Feb 24, 2013 at 15:46 | answer | added | Rodrigo A. Pérez | timeline score: 1 | |
| Feb 24, 2013 at 15:09 | history | asked | Joseph O'Rourke | CC BY-SA 3.0 |