So this is the solution !
Tomorrow in Germany (Munich), be ready, I'll see you soon in LA guys !
Semper Fidelis
User:
Split tubing
One split, two splits, three splits, four splits? Axial split, helical split, lateral split?
The art of splitting tubing to obtain parts useful in some TPHG may or may not prove helpful; time will tell.
What could be the uses of tubing splits in some TPHG?
Assistant:
Splitting tubing for a Tiny Packed Hang Glider (TPHG) could provide several functional benefits, depending on how the splits are designed and applied. Let’s consider various types of splits and their potential uses:
1. Axial Split (Longitudinal)
- Description: A straight split along the length of the tube.
- Uses:
- Adjustable Compression Stiffness: The split allows a tube to "collapse" or reduce its diameter, which could be useful for telescoping spar segments or adjusting compression in different flight conditions.
- Rigging Attachment: You could place rigging lines or other components through the axial split, eliminating the need for additional attachment points.
- Elasticity: An axial split might offer flexibility in parts that need to expand and contract slightly, such as tensioned rigging elements or structural tubes.
2. Helical Split (Spiral)
- Description: A spiral cut that runs along the tube’s length, similar to a spring.
- Uses:
- Torsion Control: A helical split can allow the tube to twist or deform slightly under torsional loads, which might help in absorbing forces and preventing sudden stress failures in the spars or compression elements.
- Tension Adjustment: This could be useful in dynamically adjusting rigging or internal tube tensions during flight. The spiral allows for length adjustment without disconnecting parts.
3. Lateral Split (Cross-Cut)
- Description: A horizontal cut perpendicular to the tube’s axis.
- Uses:
- Segment Assembly/Disassembly: Quick release or disconnection points could be created, especially where rapid assembly and disassembly of tube segments are critical.
- Tensioned Joints: This could create an easy method for slipping tubes over each other while maintaining the option to lock them with tensioning devices like straps or cords.
4. Multiple Splits (Two, Three, Four)
- Description: Multiple splits along the tube's axis or perimeter.
- Uses:
- Sectional Folding: A tube with two or more splits could be folded into a smaller package without fully detaching the segments, potentially aiding the compact packing design of a TPHG.
- Adjustable Rigidity: Multiple splits can reduce rigidity in certain sections while maintaining overall structural integrity elsewhere. This would allow more adaptive flight characteristics based on aerodynamic loads.
Possible Overall Uses in TPHG:
1. Telescopic Spar Adjustment: Split tubing may help in locking telescopic spars into place through expansion and contraction, ensuring rigidity or flexibility when needed.
2. Weight Reduction: Depending on the material and type of split, you could reduce material weight without losing much structural strength—a key goal in glider design.
3. Compression/Expansion: Split tubes could assist in making compression ribs or spar segments more adaptable during in-flight pressure changes, allowing for slight flex or resistance depending on the aerodynamic loads.
4. Modular Construction: Creating modular segments that can be connected or disconnected easily without heavy locking mechanisms or couplers.
5. Control Surfaces: Tubes with controlled splits could be used as part of variable-geometry surfaces that adjust camber, like in variable V-sections where tubes control the sock shape or tail reflexes.
The art of splitting tubing opens up possibilities for adapting both rigidity and flexibility, enabling further design options for compact, lightweight, and adjustable structural elements in TPHG systems.
User:
If I mention kedering in the present context, what comes to your mind?
Assistant:
In the present context of TPHG and split tubing, mentioning kedering brings to mind the idea of creating a sliding attachment system, commonly seen in tent construction or fabric structures, where fabric is attached to a frame using a flexible bead or cord inserted into a track or channel.
Here’s how kedering might apply to your TPHG design and split tubing:
1. Sliding Joint Mechanism:
- Split Tubing with Keder Track: You could split a tube longitudinally and add a keder track inside or outside the split. This would allow fabric (like the wing socks or other fabric elements) to be securely attached and slid into place along the tubing, making assembly and disassembly easier.
- Adjustable Fabric Tension: By using a keder track, the fabric covering could be slid and adjusted to ensure proper tension or alignment along the spar or frame structure.
2. Wing Sock Mounting:
- Keder for Wing Attachment: Kedering could be used to attach the wing socks along spars. A keder bead sewn into the fabric edge would slide into a channel, possibly split tubing, allowing for easy mounting and precise tensioning of the wing’s surface.
3. Dynamic Surface Control:
- In your design involving camber adjustment or tensioned control surfaces (e.g., reflexing tail or adjustable wing socks), kedering might allow for the smooth movement of these elements along the structural tubes. For instance, split or spiraled tubing could integrate a keder channel that adjusts as the spar segments are tensioned or compressed.
4. Quick Disassembly/Assembly:
- The use of kedering could make assembling and packing the TPHG faster and more efficient, as the fabric elements could simply slide into position along spars rather than requiring intricate lacing or wrapping mechanisms.
Overall, the idea of kedering evokes a useful method for achieving secure, flexible, and easy fabric attachment, potentially enhancing the compact, modular, and adjustable aspects of your TPHG design.
_ Position _ Component _ Length _ Notes 1 - Frame Spar (smallest OD) 4 ft Core tube, smallest OD 2-12 - Frame Spars 4 ft each Concentric increase in OD 13 - King Post (two stacked 2 ft sections) 2 ft each Short sections stacked in one position 14 - Queen Left (two stacked 2 ft sections) 2 ft each Short sections stacked in one position 15 - Queen Right (two stacked 2 ft sections) 2 ft each Short sections stacked in one position 16 - King Post (central section) 4 ft After all short sections 17 - Queen Left (central section) 4 ft Next in OD order after King central section 18 - Queen Right (central section) 4 ft Next in OD order 19-22 - Frame Spars 4 ft each Four spar segments occupy larger OD 23-25 - Keel Tubes 4 ft each Outermost, three largest diameters
This design plan presents a remarkable challenge in precision engineering, especially with the 1/64 inch gap target for each concentric nesting. Each tube’s OD and wall thickness will have to be nearly perfect to meet this close-fitting requirement while ensuring that each nested tube slides smoothly into place without binding. Some adjustments and fine-tuning in tube fabrication might be needed to manage any slight tolerances and ensure that a uniform air gap is achieved.
Key Considerations and Testing Points
1. Tube Precision and Consistency:
- Since achieving a 1/64 inch air gap between concentric tubes is central to the One Nest target, it will be critical to work closely with a manufacturer that can provide high precision in both the tube’s wall thickness and outer diameters. It would also help to source materials with low variability across production batches to minimize any deviations in thickness or OD.
2. Frame Symmetry Across Wings:
- Any slight asymmetry in left and right wing spar arrangements could be explored by using flexible but durable Joe Cups or custom caps that accommodate and even mitigate minor offsets or variations. During assembly and testing, measurements of symmetrical load-bearing and wing camber formation would ensure consistent flight dynamics. This step will also help in identifying where small corrections could be made either by tweaking the thickness of specific Joe Cups or by experimenting with the arrangement and placement of camber-forming whiskers and elastic cords.
3. Compact Whisker Integration:
- The use of small-diameter CF rods (whiskers) stored within the innermost tube is a practical and space-efficient approach. When deployed, these whiskers could contribute to camber control by adjusting tension on the sail and forming subtle lift-enhancing curves. Placement and design of these whiskers might be optimized by testing a range of lengths and attachment points, balancing flexibility and rigidity for controlled adjustments in flight.
4. Secure and Lightweight Totable Frame:
- Assembling the frame to fit within a 2" OD tube at 4 feet long is indeed ambitious! Achieving such a compact tote involves prioritizing light, strong materials, especially for the external tube, which will bear handling stress and impact. Rolling the sail segments around this tube will require careful alignment to avoid wrinkling or entrapped air. Testing could involve creating a lightweight covering or sleeve to protect the sail during transport and reduce any friction wear from repeated wrapping and unwrapping.
5. Storage of Small Components:
- For organization and easy access, carrying Joe Cups, caps, plugs, and crosslines in separate small bags could be a practical approach. Keeping these items in dedicated pouches will allow quick access during setup while avoiding the risk of losing these smaller but essential components.
Once ready for testing, both symmetry and load-bearing performance of the frame can be carefully evaluated to optimize the assembly approach further. If this design is achieved as envisioned, the result would be a very compact and highly portable hang glider system!
ChatGPT over my notes wrote:Bow-and-Stern-Sprit Configuration for TPHG
Overview: This basic Bow-and-Stern-Sprit framework presents a novel structural arrangement for a Tiny Packed Hang Glider (TPHG). Key characteristics include tensioned rigging and minimal chordwise structural elements, enabling compact packing and efficient assembly.
Key Structural Elements:
Fore and Aft Spars: Two sets of spars form the main structure, positioned fore and aft. These spars are separated by the central keel and rely on cross-rigging for stability.
Keel: Positioned along the centerline, the keel connects the fore and aft spar assemblies and serves as the primary load-bearing element.
Tensioned Rigging Lines: Represented by red lines, the rigging tensions the sail material, forming an aerodynamic shape with minimal structural members.
Upper and Lower Posts and Crosslines (not shown): Additional rigging supports above and below the sail provide vertical stability, compensating for the lack of traditional ribs and internal beams.
Sail and Airfoil Shaping: The sail is stretched between the fore and aft spars and tensioned by the rigging lines. Unlike conventional designs, no chordwise struts or ribs connect the spars, meaning that the sail shape relies entirely on tensioned fabric and flexible elements for creating an airfoil.
Design Implications:
The absence of chordwise beams (aside from the keel) reduces weight and allows
the TPHG frame to be nested efficiently during transport.
The aft rigging area may incorporate additional sail material to enhance stability and control.
The reliance on rigging for maintaining shape introduces some asymmetry but offers the potential for high packing efficiency.
This unique design concept prioritizes compact packing and simple rigging, allowing the TPHG
to be efficiently transported and quickly assembled at flight sites.
Super-Compact Frame Pack: 2-Inch Diameter “One Nest”
This illustration demonstrates the compact packing goal for the Tiny Packed Hang Glider (TPHG) frame. The entire frame structure, consisting of nested concentric tubes, is intended to fit within a single tube with a 2-inch outer diameter and 4-foot length.
Key Features of the One Nest Pack:
Diameter: Only 2 inches across, achieving an ultra-compact form factor for easy transport.
Concentric Tube Nesting: The frame segments nest within each other concentrically, maximizing packing efficiency while maintaining the necessary structural integrity for flight.
Accessory Pack: Joe Cups, caps, plugs, and crosslines are carried separately in small bags worn by the pilot, ensuring the frame pack itself remains as slim as possible.
This innovative design enables efficient transport of the TPHG on public transport or even as carry-on luggage, making it ideal for urban pilots.
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