I've PM'ed you, but will add more detail here, the gist is that within the wood machining world there are quite a few bleeding edge mechanical engineering problems, mainly focused on how you reliably make a non-standard board of wood into a standard part, without significant human input.
As hobbyists we're kind of closeted away from the timber industry proper, but I suspect that you will find more interesting and relevant challenges there, albeit more of an incremental improvement type than a new invention or product.
Depending on your modules, preferences and degree track you'll find problems related to control systems, SCADA, mechanical reliability, precision measurement, LEV/HVAC, tooling design and tool holding...
To give an example, running a 4-side planer moulder to make PSE, an operator sets the pressure shoes to a happy medium which will straighten most pieces of timber in the pack to process, and then runs any really bowed ones last, changing the settings for each piece. With appropriate sensing, the machine can determine the deformation, and dynamically adjust the feed speed, pressure and feed roller height to suit each piece, much in the way a skilled joiner would using a Surface Planer.
We know this is possible, as primary sawmilling uses advanced computer analysis to pick the best orientation to saw a log, minimising waste and automatically adjusting a whole line of band-resaws and feed carriages... But because a plank is more easily bent, the tolerances tighter, and the number of pieces to assess in a given time to match current throughput rates higher, the whole system needs to be more advanced.
Inside the planer there are thus multiple engineering challenges:
- Sensing the shape of the board on the infeed.
- Rapid adjustment of 4-8 cutter blocks, 3-4 feed tables, 2-3 fences, 6-10 feed rollers and 4-12 pressure shoes all in motion.
- Maintaining positional accuracy of those adjustments.
- Sensing the shape change in the board after each cutter head.
- Doing that all in under ½ a second.
There is a of wealth of information available on the existing knowledge in wood machining, with the
IWSc/IoM³, the US Forest Service, BM Trada, BRE, the (now defunct) TTTA, FIRA and countless manufacturers of machines and large sawmilling concerns taking a keen interest for nigh on 150 years now.
I'm not 100% where you'd be able to access these resources, but the library holdings of institutions which delivered the old IWSc Certificate (now paused for restructuring under the wood technology society), along with universities with a strong wood science / forestry background (Bangor and Aberdeen being foremost, with Edinburgh Napier, Aberystwyth and Herriot-Watt also having strong departments).