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A general method for the creation of dilational surfaces
Freek G J Broeren1, Werner W P J van de Sande2, Volkert van der Wijk2
1Department of Precision and Microsystems Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628, CD, Delft, The Netherlands. f.g.j.broeren@tudelft.nl.
We developed a general method for creating dilational structures from any surface. This approach ensures all movements are tangent to the surface, avoiding volume obstruction for versatile shape-changing applications.
Area of Science:
- Mechanical Engineering
- Materials Science
- Geometry
Background:
- Existing dilational structures have limitations in shape adaptability and can obstruct enclosed volumes.
- Current designs are often restricted to specific curvatures and require perpendicular movements.
Purpose of the Study:
- To present a universal method for designing dilational structures applicable to arbitrary surfaces.
- To enable surface dilation with movements exclusively tangent to the surface, preserving enclosed volume.
Main Methods:
- Triangulating arbitrary target surfaces (2-manifolds).
- Replacing triangular faces with pantograph mechanisms using a collision-avoiding tiling algorithm.
- Demonstrating the method with examples of varying complexity and Gaussian curvature.
Main Results:
- A generalizable method for creating dilational structures from any surface was established.
- The method allows for tangent-only surface motion, preventing volume obstruction.
- Theoretical scalability from full expansion to a single point is achieved.
Conclusions:
- The proposed method offers a versatile solution for designing dilational structures for diverse applications.
- This technique overcomes limitations of current designs, enabling efficient and adaptable shape-changing mechanisms.
- The approach is theoretically applicable to any surface, paving the way for novel engineering designs.
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