Foreword:

Sigma Design & Consulting is proud to help all its clients developing and prototyping various electromechanical instruments, probes, and instruments used in a wide range of industries. We are happy to share our experience, and should you need help, please contact us.

Developing and Prototyping Electronic Hardware and Mechanical Components

Developing a new electronic hardware product with integrated mechanical components involves a step-by-step approach to ensure a seamless transition from concept to production. This guide provides technical insights into electronic and mechanical design, prototyping, and manufacturing.

1. Simplify Your Product Design

Minimize complexity in both electronic and mechanical designs to reduce costs and production challenges. Evaluate the necessity of every feature for functionality and market relevance.

Example:
Aesthetic curves in an enclosure might improve design appeal but could complicate injection molding, increasing production costs.

2. Build a Proof-of-Concept (POC)

Start with a POC prototype to test basic functionality. Use off-the-shelf components for the electronics and simple 3D-printed or CNC-machined parts for the mechanical design. This stage focuses on functionality over aesthetics or manufacturability.

3. Develop a Preliminary Production Design

Create a preliminary production design that incorporates:

  • Electronic System Design: Develop a block diagram to define key functions and interconnections.

  • Mechanical Design: Begin with a rough CAD model to outline physical dimensions, layout, and enclosure features.

Both designs should consider manufacturability, cost, and performance early on.

4. Select Components and Create a BOM

Electronic Components

Choose microcontrollers, sensors, and connectors that meet functional and cost goals. Start a preliminary Bill of Materials (BOM) listing these components.

Mechanical Components

Determine materials for the enclosure and mechanical elements. Consider factors such as:

  • Material strength (e.g., ABS plastic for durability, aluminum for lightweight parts).

  • Surface finish (e.g., textured, glossy, or matte).

  • Environmental resistance (e.g., waterproofing or UV protection).

5. Estimate Production Costs

Calculate costs for both electronics and mechanical components:

  • Electronic Costs: Include PCBs, assembly, and packaging.

  • Mechanical Costs: Factor in prototyping, injection molding, material selection, and surface finishing.

Account for production overheads such as warehousing and logistics.

6. Design Schematic and Mechanical Drawings

Electronic Design

Develop a detailed schematic using tools like Altium Designer. This blueprint will guide PCB layout and component placement.

Mechanical Design

Using CAD software (e.g., Autodesk Inventor, SolidWorks, Autodesk Fusion 360, or PTC Creo), design detailed mechanical drawings of the enclosure and any supporting structures. Include:

  • Dimensional tolerances.

  • Snap-fit features or screw mounts.

  • Ventilation or heat dissipation features if applicable.

7. Develop the PCB and Mechanical Layout

PCB Layout

Design the PCB layout to optimize space and functionality. Consider:

  • Placement of high-speed signals and power lines.

  • Minimizing electromagnetic interference (EMI).

Mechanical Layout

Create a digital assembly of the mechanical and electronic components to ensure a proper fit. Verify the alignment of connectors, buttons, and displays.

8. Finalize the BOM

Expand the BOM to include:

  • Electronic Components: Add resistors, capacitors, and other small components.

  • Mechanical Components: Include screws, adhesives, and finishing materials.

9. Prototype the PCB and Mechanical Parts

PCB Prototyping

Manufacture the PCB and assemble components for testing. Use suppliers like Rush PCB  or Seeed Studio.

Mechanical Prototyping

Produce enclosure prototypes using:

  • 3D Printing: For rapid iterations and testing.

  • CNC Machining: For more durable prototypes using production-grade materials.

10. Test, Debug, and Refine

Evaluate the integration of electronic and mechanical parts:

  • Test functionality and fit of the enclosure.

  • Debug electronic circuits and ensure reliable operation.

  • Refine mechanical design for ease of assembly and user ergonomics.

11. Optimize the Enclosure Design

Based on feedback, update the enclosure's CAD model:

  • Simplify for manufacturability (e.g., reduce undercuts for injection molding).

  • Improve aesthetics and ergonomics.

  • Ensure compatibility with certification requirements (e.g., adding grounding points for electronics).

12. Transition to Injection Molding

For mass production:

  1. Develop a high-precision mold using steel or aluminum based on production volume.

  2. Adjust the enclosure design for injection molding rules, such as consistent wall thickness and draft angles.

13. Certify the Product

Certify both electronic and mechanical designs. Mechanical certifications might include material safety (e.g., FDA compliance for food-grade materials) or environmental standards (e.g., IP ratings for water resistance).

14. Scale Up Production

Work with manufacturers to transition from prototyping to production:

  • Electronics: Scale PCB production with automated assembly.

  • Mechanics: Use injection molding for enclosures and CNC machining for metal parts.

Optimize production lines for efficiency and quality assurance.

Conclusion

By integrating electronic and mechanical design workflows, you can streamline the development of complex hardware products. Adopting a step-by-step approach minimizes risks, ensures cost-effectiveness, and accelerates time-to-market. Success lies in balancing functionality, aesthetics, and manufacturability at every stage.

Sigma Design & Consulting has extensive experience and is ready to help you navigate your design. If you’d like a more detailed focus on any specific step, or assistance let us know.