3D Scanning and CAD enable aesthetically matched transhumeral prosthetics

Why It Matters

This approach addresses a common aesthetic concern in prosthetic design, moving beyond purely functional considerations to enhance user acceptance and psychological well-being. It demonstrates how digital modelling can bridge the gap between technical requirements and personal identity.

Key Finding

The study successfully demonstrated that by using 3D scanning and CAD, a prosthetic limb could be designed to visually match the user's existing limb, and then manufactured using additive techniques, though integrating functional components required careful consideration.

Key Findings

• 3D scanning and CAD can produce a prosthetic design that mirrors the contralateral limb's appearance.
• Integrating mechanical components into custom-designed prosthetic shells presents engineering challenges.
• Additive manufacturing is a viable method for producing these customized prosthetic designs.

Research Evidence

Aim: How can 3D scanning and CAD be integrated to create aesthetically matched transhumeral prosthetic designs for additive manufacturing?

Method: Digital Modelling and Prototyping

Procedure: A 3D scan of the user's intact limb was captured. This scan data was then used in CAD software to generate a mirrored design for the transhumeral prosthetic, ensuring a symmetrical appearance. The process also involved integrating mechanical components for basic actuation within this custom-designed prosthetic shell, followed by additive manufacturing.

Context: Prosthetic design and additive manufacturing

Design Principle

Form follows identity: Design elements should consider the user's psychological and social needs, not just functional requirements.

How to Apply

For any custom-fit product, consider using 3D scanning to capture precise user anatomy and CAD to generate designs that are not only functional but also aesthetically pleasing and personalized.

Limitations

The study focused on basic actuation and aesthetic mirroring; further research is needed for complex functional integration and long-term durability.

Student Guide (IB Design Technology)

Simple Explanation: You can use a 3D scanner to copy one of your arms and then use computer software to make a mirrored design for a prosthetic arm that looks the same.

Why This Matters: This research shows how technology can be used to make medical devices, like prosthetic limbs, look more natural and feel more personal to the user, which is important for their confidence and how they use the device.

Critical Thinking: Beyond aesthetic mirroring, what other user-centric design considerations are crucial when developing custom prosthetics, and how can digital modelling facilitate these?

IA-Ready Paragraph: The research by Rhyne et al. (2017) demonstrates the potential of integrating 3D scanning and computer-aided design (CAD) to create aesthetically congruent transhumeral prosthetic designs. By capturing a 3D scan of the user's existing limb, designers can then utilize CAD software to mirror this form, resulting in a prosthetic that visually matches the natural anatomy. This approach not only addresses functional needs but also enhances user acceptance by considering personal identity and appearance.

Project Tips

• When planning your design project, consider how the visual appearance of your product will affect user perception and adoption.
• Explore how digital tools like 3D scanning and CAD can be used to create highly personalized or adaptive designs.

How to Use in IA

• Reference this study when discussing the use of digital modelling and scanning techniques to achieve user-specific design outcomes, particularly for aesthetic considerations in personalized products.

Examiner Tips

• Demonstrate an understanding of how digital modelling can be used to address both functional and aesthetic requirements in a design project.

Independent Variable: Use of 3D scanning and CAD for design mirroring.

Dependent Variable: Aesthetic congruence of the prosthetic with the existing limb.

Controlled Variables: Type of prosthetic (transhumeral), additive manufacturing process, basic mechanical actuation components.

Strengths

• Direct application of digital modelling for personalized product design.
• Addresses a significant user-centric aspect (aesthetics) in prosthetic development.

Critical Questions

• How might the cost and accessibility of 3D scanning technology impact the widespread adoption of this design approach?
• What are the ethical considerations when designing prosthetics that aim to perfectly replicate or mirror natural anatomy?

Extended Essay Application

• An Extended Essay could explore the biomechanical implications of aesthetically matched prosthetics, investigating if visual similarity influences user embodiment and motor control, or compare the efficiency of traditional prosthetic design workflows against this digital modelling approach.

Source

Reverse Engineering a Transhumeral Prosthetic Design for Additive Manufacturing · 2017 · 10.26153/tsw/16963