Dome Hub Spoke Retention for Tool-Free Strut Assembly
Solution Overview
Problem
Geodesic dome structures using struts with flattened ends lack sufficient support, require cumbersome and time-consuming assembly processes, and necessitate multiple builders and tools, leading to increased costs and inferior structural characteristics.
Innovation Solution
A dome hub system that connects struts without supplemental hardware, featuring a spoke with an engagement slot and strut band that receives and retains the strut end without flattening, allowing for assembly by a single person using a hub with radially extending spokes and a disk that attaches releasably.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If struts with flattened ends are used to join dome components, then assembly can be achieved with simple components, but structural strength is greatly diminished
Solution Approach 1:
The hub is segmented into multiple spokes that radiate from a central body, with each spoke independently receiving and retaining a strut. This segmentation allows each spoke to be optimized for strut retention while the central body provides overall structural integration, resolving the contradiction between simple assembly and structural strength.
Solution Approach 2:
The strut is received within the spoke structure, with the spoke acting as a housing or container for the strut end. This nesting arrangement allows the strut to be securely retained within the hub without requiring external fasteners, maintaining both assembly simplicity and structural integrity.
2Strength
If traditional fastening methods with bolts and nuts are used, then structural strength is maintained, but assembly becomes cumbersome and time-consuming
Solution Approach 1:
Traditional fastening components (bolts, nuts, washers) are completely extracted from the system. Instead, the spoke structure itself is designed to directly retain the strut through its geometric configuration and flexible edges, eliminating the time-consuming fastening process while maintaining structural strength through the integrated spoke-strut connection.
Solution Approach 2:
The spoke structure is designed to be self-retaining, where the flexible edges automatically grip the strut when inserted. The spoke's geometry and material properties enable it to self-adjust and secure the strut without external intervention or additional fastening components, dramatically reducing assembly time while maintaining connection strength.
3Manufacturing precision
If multiple builders and tools are required for assembly, then proper alignment and structural integrity can be achieved, but costs and complexity increase
Solution Approach 1:
The spoke edges are designed to be flexible rather than rigid, allowing them to dynamically adjust during assembly. This flexibility enables the spoke to accommodate slight misalignments and automatically conform to the strut's position, achieving proper alignment without requiring multiple builders or specialized alignment tools, thus reducing assembly complexity while maintaining precision.
Solution Approach 2:
The material properties of the spoke are selected to provide optimal flexibility and elasticity. By changing the physical parameters of the spoke material and geometry, the system achieves self-aligning capabilities during assembly, allowing single-person assembly while maintaining precise strut alignment and structural integrity.
4Shape
If struts are bent to form correct angles, then proper dome geometry is achieved, but structural strength is diminished and assembly becomes more difficult
Solution Approach 1:
Instead of bending the rigid strut to achieve the correct angle, the approach is inverted: the hub spoke is designed with the correct angle built-in, and the flexible spoke edge is used to conform to and retain the straight strut. This inversion preserves the full structural strength of the unbent strut while achieving the required dome geometry through the angled spoke configuration.
Data Source
AI summary
A dome hub includes a body and a spoke extending radially from the body. The spoke is configured to receive a dome strut. The spoke includes a strut band configured to receive an end of a dome strut. A dome assembly kit includes a strut and a hub. The hub retains the strut within a spoke without threaded fasteners when assembled. The spoke includes a strut band that receives an end of the strut when assembled. A dome assembly method includes using a hub with a spoke and a strut band. The method includes using a strut and inserting the strut into the spoke. The strut is retained within the spoke without threaded fasteners. The method includes sliding the strut toward a center of the hub until an end of the strut is positioned against the strut band.