Problem Statement
In the previous iteration of the FSAE Electric Vehicle, the low-voltage electrical enclosure utilized Deutsch AS-series connectors interfaced with the internal PCB via short pigtail harnesses. While these connectors are known for their ruggedness and environmental sealing, their implementation introduced unnecessary complexity in packaging, wiring, and assembly. This is why we chose to adopt the JAE MX23A-series board-side connectors.
The internal routing of wires between the enclosure’s external connectors and the PCB led to several critical issues.
- Cable congestion inside the enclosure worsened serviceability and increased the risk of interference.
- Difficult maintenance, as faults with internal wiring and the fuse plane required full disassembly.
- Smaller enclosure size to accommodate tolerancing and having saved space from internal routing removal.
- Multiple electrical failure points, with additional crimp/solder connections increasing resistance and risk under vibration or thermal cycling.
These drawbacks negatively impacted serviceability, reliability, and manufacturing efficiency, which are crucial in a high-performance motorsport environment. To address these issues, the enclosure was redesigned to implement board-side connectors. These connectors are mounted directly to the enclosure wall and terminate directly onto the PCB, eliminating the need for internal pigtails. Key features of the new design include:
- Custom 3D-printed housings for connector mounting, incorporating tight-tolerance alignment and sealing features
- Carbon fibre reinforcement plates to provide structural rigidity and precise connector retention.
- Integration of automotive-grade sealing elements (O-rings/gaskets) to maintain waterproofing and achieve IP67 compliance
- Reduction in total connector stack height and improved interface accessibility.
Bill of Materials (BOM)
The following table lists the components used in the prototype, including part numbers, quantities, materials, estimated costs, and potential suppliers.
Item | Component | Part Number | Qty | Material | Cost ($) | Supplier | Notes |
1 | 34 Pin Connector | MX23A34SF1 | 5 | Plastic/Metal | Sponsor | JAE | Harness Side |
2 | 34 Pin Connector | MX23A34NF1 | 5 | Plastic/Metal | Sponsor | JAE | Board Side |
3 | 40 Pin Connector | MX23A40SF1 | 2 | Plastic/Metal | Sponsor | JAE | Harness Side |
4 | 40 Pin Connector | MX23A40NF1 | 2 | Plastic/Metal | Sponsor | JAE | Board Side |
5 | Aluminum Hex Core | DS18B20 | 0.1m^2 | Aluminum | Sponsor | --- | 1/10" thick |
6 | 3D Printed Walls | ASA + CF | 300g | Thermoplastic | 11.00 | Bambu Labs | PCABS |
7 | Standoffs | TBD | 8 | Nylon | 6.00 | Digi Key | PCB Standoffs |
8 | Fasteners (Screws, M3) | TBD | 6 | Stainless Steel | 3.00 | McMaster | For sealing (gaskets) |
9 | Gaskets | TBD | 2 | Silicone/Rubber | 5.00 | TBD | Waterproofs intersections |
10 | Carbon Fibre (Twill) | --- | 0.6m^2 | Carbon Fibre | Sponsor | --- | Layups |
11 | Carbon Fibre L-Brackets | --- | 6 | Carbon Fibre | Sponsor | --- | Additional Support |
CAD of Under Seat Enclosure
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CAD of CAN Node Boxes
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