PDR - EBox Redesign 2022/23

Owned by
Joshua Harper
Last updated: Nov 13, 2022
3 min read

Project Scope

Main motivation to redesign the ebox is to accommodate new board/internals. Redesign electrical box to ensure adequate temperature management & monitoring for desert conditions. High temperatures within the electrical box can lead to overheating of electrical components (causing potential damage). Ebox should be dust/dirt-proof and provide exterior ports to connect to the rest of rover hardware.

Success Factors

Relevant Competition Rules

  • The maximum allowable mass of the rover when deployed for any competition mission
    is 50 kg. The total mass of all fielded rover parts for all events is 70 kg.

Criteria

Constraints

Criteria

Constraints

Maintain airflow within ebox [check appropriate temp range]

Weight no more than 2.30kg when empty (weight of current ebox)

Easy access to all internal components

Fit all components listed on https://uwaterloo.atlassian.net/wiki/spaces/UWRT/pages/43268014471

Temperature monitoring

  • Main concern is the 24V buck converter as it deals with very high currents

IC: max temp 125 C

  • BMS has built-in temperature sensor

  • use this to get an idea of temp inside ebox

  • ensure 24V buck has efficient airflow

Budget of $150

  • aluminum sheet metal

  • necessary connectors/cable glands

(https://www.protocase.com) - $2000 URC budget

Organized wire routing

  • use zip ties where necessary to allow for easy access to all internal components

Able to be manufactured in student machine shop

Seal box to prevent dust/dirt from entering

Electrically insulate ebox from chassis

Make as compact (yet accessible) as possible

 

Design Improvements

  • Perhaps mount on side with filtered vents at top to allow heat to rise out from enclosure

Design Concepts

  • Pictures, sketches, low level CAD of design concepts

  • How would these systems work?

  • What are the risks associated with each individual design concept?

Heatsink enclosure for better heat dissipation - need to look into manufacturing complexity
Have an angled side with fans to allow heat to dissipate upwards as hot air rises

 

Design Proposal

  • If you only have one design concept, can merge with section above

  • What design concept do you want to move forward with?

    • Justify this decision by completing the following:

      • How could this design compare to established criteria and constraints? Is there risk associated with achieving any requirements?

      • How are identified design risks planned to be mitigated?

      • Very quick thoughts on what resources you may need to build and fabricate your design

  • What is your proposed project timeline?

    • Propose a CDR date

Additional Resources

$2000USD credit to protocase

https://www.protocase.com/