Further specifications received over email by Caleb Amos 13/03/25:

1. PCB needs to be at least 2600mm^2, 1.4mm thick, and no part of it should be less

than 10mm wide.

There should be 2.5mm clearance across one side of the whole board for components.

The PCB may be designed in 2 parts if required with negligible extra cost, as long as the

increased assembly time is considered.

Jason notes: The 2.5mm clearance across one side is to account for soldered

components on the board including electronic chips, capacitors, resistors etc. that is to

be on one specific side and so there needs to be a 2.5mm gap across this side.

2. One component on the PCB requires cooling. It is 5x5mm and 2.5mm high, and

requires cooling through thermal conduction to the case.

Jason notes: see item circled in red in figure below.

This component is assumed to generate 5W of heat under peak loads.

We would stick a thin thermal pad on the top of this which would contact the case

above it. The rest of the PCB is assumed to generate 5W distributed throughout, and

does not require direct cooling.

An option for simulation: make sure no external part of the case can get above 40

degrees (or 45 for materials other than aluminium) as the conductivity of aluminium

makes it seem hotter to a user.

Jason notes: In this case we will assume a total of 10 W heat dissipation: 5 W from the

board and 5 W through the voltage regulator (circled in red above). The voltage regulator

is to make contact with a pad that is to contact the case. The case is to act as a heat

sink for the voltage regulator.

3. The PCB does not necessarily require its own attachment to the case if the

attachments of the board-mounted components to the case are rigid enough.

This is possibly an opportunity for simulation to ensure there's no unwanted vibration of

the PCB.

Jason notes: Vibration analysis is out of the scope but could be noted as future work.

4. The hub must have the following list of components, each attached to the PCB:

a. 3x 0B LEMO Sockets. These are assumed to be 9-pin connectors to simplify the

process. PDF is attached for the specifications of these sockets and connectors. A few

types for physical prototyping have been provided, but they should not be limited to

these kinds.

These requirements for these plugs are limited to fixed sockets with part numbers that

fit E_G.0B.309.____ (the last 4 numbers don't matter)

Jason notes: following telephone discussion with Caleb on 13/03/25 it was concluded

that students will chose one of the three Lemo plug samples provided and use all three

of the same type for the chosen design to narrow the scope and reduce complexity.

Lemo specifications as follows:

https://url.au.m.mimecastprotect.com/s/0gVxCjZryVCj96lm8I7svUmQS5I?domain=dri

ve.google.com

The Lemo plugs provided can be sourced on the above PDF as follows (page numbers

given are for PDF viewer not those written on PDF document):

EEG on page 21- 22. On page 22 ECG with two nuts with right angle contacts. The fly

lead connector EFG on page 21. Black base connector EXG page 29.

b. A USB C port

c. A button near the USB C port

Jason notes: Caleb to provide specifications if available: currently in progress.

d. A light pipe for good presentation of light from a board-mounted LED.

Any light pipe from this list may be used:

bivar.com/led-indication/rigid-light-pipes/2board-mount-rigid-light-pipes-led-

indication-2/6slp-board-mount-rigid-light-pipes-led-indication-2/

Jason notes: it is fine to give freedom on any light pipe students wish to chose in

addition to those light pipes provided as samples.

e. A hole for the board-mounted cable that plugs into the DJI transmitter. This hole

should be designed and sized to avoid damage to the cable.

5. A current estimate for machining time is 15 minutes total for all components of the

assembly, machined on an MB-4000H 4-Axis Horizontal Machining Centre

An interesting thing to manage is that machining 1 part at a time would take 25 minutes

due to tool and pallet changing.

Teams should assume that 5 minutes per unique component is required for tool and

pallet changing, but if they design a way to machine several parts at once, the 5

minutes stays constant and is spread. i.e. if they are machining 5 parts at once there is

only 1 minute per part for tool and pallet changing, or 50 parts at once is only 6

seconds.

Jason notes: Existing fusion hub has two parts. All components designed are to be

developed specifically for a 4 axis machine. Current fusion hub is machined in a 4 axis

machine based on 4 parts at a time. It takes 10 minutes for operator to unload and load

new set of parts. Total machining time: 2 hours (for 4 complete parts). Once machined

then washed and sent off for anodizing. Based on a total of 2 hours for 4 parts, this is an

average machining time of 30 minutes per fusion hub. A big way to cut down machining

time is to machine multiple parts at a time. Students are to focus on machining time for

a single part they design and if time allows then we will consider machining multiple

parts.