Week 3

Download Detailed Slides: PDF Version | Keynote Version

Comprehensive presentation covering all design rule tests, results, and analysis methodology.

Print Strategy: By grouping all supported tests in one print and all unsupported tests in another, we were able to efficiently evaluate printer capabilities while minimizing material waste and print time. This approach allowed for direct comparison between different test geometries and provided comprehensive data on the printer's performance across various design constraints.

The supported tests focused on features that should print reliably, while the unsupported tests pushed the boundaries of what the printer could achieve without additional support structures.

Handgripper for Locomotive Age Assessment

I hope to design and fabricate a handgripper to measure age based on hand grip strength. This builds on our aging biomarker research by focusing on locomotive age assessment.

The idea is to measure functional decline due to aging across multiple modalities:

• Cognition: Memory, attention, reasoning, and problem-solving
• Locomotion: Mobility, balance, and muscle strength
• Sensory: Vision, hearing, and touch
• Vitality: Energy levels, nutrition, and sleep
• Psychological: Emotional well-being, resilience, and social connections

Last week we measured cognition with reaction time - this week we focus on locomotive age through grip strength.

First slinky design - exploring the magic spring concept

Design Description: This first slinky design represents my initial exploration into creating a 3D printable magic spring. The design focuses on creating a helical structure that can collapse and expand while maintaining its structural integrity.

This design was inspired by the classic slinky toy and the concept of creating a "magic spring" that can be 3D printed in one piece, demonstrating the unique capabilities of additive manufacturing.

Video Demonstration

Watch the slinky in action: YouTube Video - Magic Spring Demonstration

3D Printable Magic Spring

Download the original design: Printables - Slinky Magic Spring

Hackaday Project

Explore the technical details: Hackaday - 3D Printed Magic Spring

The Hackaday project provides comprehensive documentation including Java code for generating G-code, print parameters, and detailed instructions for creating 3D printable magic springs. The project includes multiple iterations of the code with different features like temperature control, spiral priming, and delta printer compatibility.

First slinky print in progress - demonstrating 3D printing of complex helical geometry

Print Process Description: The printing process successfully demonstrated the capability of FDM 3D printing to create complex helical geometries. The slinky was printed using PETG material with optimized settings for layer adhesion and dimensional accuracy. The print required careful support structure management and precise temperature control to achieve the desired mechanical properties.

Key printing parameters included: 0.4mm nozzle diameter, 0.2mm layer height, PETG material, and optimized print speed for complex geometry. The print time was approximately 55 minutes for the complete slinky structure.

Complete printing process video showing layer-by-layer construction of the slinky

Video Analysis: This video demonstrates the successful 3D printing of the complex slinky geometry, showing how the printer handles overhangs, bridging, and intricate details. The printing process reveals the importance of proper support structures and temperature management for achieving functional mechanical properties.

Notable aspects: smooth layer transitions, successful overhang printing, proper bridging between coil segments, and consistent material flow throughout the complex geometry.

Key Hypothesis: Since this is a slinky design, the flexible nature of the printed object should allow for pulling and stretching to remove support material from between the coils. This hypothesis drives the design optimization process, testing how many revolutions can be successfully printed while maintaining the ability to remove internal supports through mechanical manipulation.

This approach challenges traditional 3D printing constraints by leveraging the inherent flexibility of the slinky geometry to overcome support removal limitations, potentially enabling more complex and longer helical structures than would otherwise be printable.

Support Removal Analysis: Initial attempts at simply breaking support material proved ineffective due to the complex internal geometry of the slinky coils. The support material was too tightly integrated with the helical structure to be removed through mechanical breaking alone.

The razor method, while effective, requires extreme caution and carefulness to avoid damaging the delicate slinky structure. This process demands patience and precision to successfully remove internal supports without compromising the print quality.

Success Analysis: The successful slinky prints demonstrate the viability of 3D printing complex helical geometries with proper support removal techniques. The prints maintain their structural integrity and exhibit the expected slinky behavior, validating both the design approach and the fabrication process.

Key achievements: successful support removal, maintained geometric accuracy, functional mechanical properties, and reproducible results across multiple prints.

Fine snipping process - precise support removal for clean slinky functionality

Snipping Process: The final support removal required careful snipping with precision tools to achieve clean separation between the slinky coils and support material. This delicate process was essential for maintaining the structural integrity while enabling proper slinky movement.

Key considerations: maintaining coil geometry, avoiding damage to the helical structure, and ensuring smooth movement between coils.

Test Success: The slinky successfully passed the staircase test, demonstrating proper mechanical functionality with smooth coil movement and the characteristic slinky behavior. This validates both the design approach and the 3D printing process for creating functional mechanical objects.

Key achievements: proper coil separation, smooth movement, maintained structural integrity, and classic slinky behavior.

Print Success Analysis: The first slinky print successfully demonstrated the viability of 3D printing complex helical geometries. The printed slinky maintained its structural integrity and demonstrated the expected mechanical properties, proving that additive manufacturing can create functional objects with intricate geometries that would be impossible to manufacture using traditional subtractive methods.

Key achievements: successful overhang printing, proper layer adhesion, maintained geometric accuracy, and functional mechanical properties suitable for the intended slinky behavior.

Darth Vader sculpture - complex geometry with dark surfaces and intricate details

Object Description: This detailed Darth Vader sculpture features complex geometry including flowing cape details, helmet ridges, and facial features. The dark surface material and intricate details present an excellent challenge for 3D scanning technology, testing both the system's ability to capture fine details and handle challenging surface properties.

The sculpture's combination of organic curves, sharp edges, and dark surface finish makes it an ideal test subject for evaluating scanning system performance across different surface types and geometric complexities.

Failed scan result using default scanner settings - insufficient detail capture

Scan Failure Analysis: The default settings failed to capture sufficient detail from the dark Vader sculpture. The resulting mesh shows significant gaps, missing geometry, and poor surface reconstruction. This demonstrates the importance of optimizing scanner settings for specific object characteristics.

Key issues identified: insufficient lighting for dark surfaces, inadequate resolution settings, and suboptimal scanning angle coverage for complex geometry.

Video demonstration of scanner optimization process and parameter adjustment

Optimization Process: This video demonstrates the iterative process of adjusting scanner settings, lighting conditions, and scanning parameters to achieve optimal results. The process involved multiple attempts with different configurations to find the best balance between detail capture and scanning efficiency.

Key optimization steps included: adjusting lighting intensity, modifying scanning resolution, optimizing turntable speed, and fine-tuning surface detection parameters for dark materials.

Successful 3D scan result with optimized settings - improved detail capture and surface reconstruction

Successful Scan Analysis: The optimized scan successfully captured the complex geometry of the Vader sculpture, including fine details like helmet ridges, cape folds, and facial features. The resulting mesh shows good surface reconstruction with minimal gaps and accurate geometric representation.

Key improvements achieved: enhanced detail capture, better surface reconstruction, reduced scanning artifacts, and improved geometric accuracy for complex organic shapes.

Post-Processing Workflow

1. Initial Processing: Start with fused STL from scanner software
2. MeshLab Alignment: Use MeshLab to align model to axes for proper orientation
3. Meshmixer Cleanup: Import to Meshmixer, select Vader, and remove background elements
4. Edge Smoothing: Smooth edges using Meshmixer tools (advice from ChatGPT consultation)
5. Platform Removal: Remove floating platform to create full surface Vader
6. Solid Conversion: Make model solid for 3D printing compatibility
7. Final Alignment: Return to MeshLab for final alignment adjustments
8. Export & Slice: Export as 3MF, slice with support everywhere (failed without support)

Successfully printed Vader sculpture - demonstrating 3D scan to print workflow

Print Success: The printed Vader sculpture successfully demonstrates the complete workflow from 3D scanning to 3D printing. Despite the complex post-processing requirements, the final print maintains good detail and structural integrity, proving the viability of scanning-to-printing workflows for complex organic shapes.

Key achievements: successful mesh cleanup, proper alignment, effective support generation, and successful printing of complex scanned geometry.