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Board to board connections in multi-PCB project

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Trotters_Independent2:
My team are entering into a competition which involves designing and building of a low speed electric vehicle. We are designing a multitude of different PCBs to implement things like telemetry, sensing of various voltages/currents/temperature etc and they all communicate with the main "CPU" PCB via CAN bus.

I am hoping to make connecting the PCBs together as simple as possible and cut down on any “rat’s nest”, as we will likely need to disassemble the vehicle for transporting it and re-assemble it at the competition venue. I only really want a single cable, providing all the necessary power supplies and CAN bus between the PCBs. The cable is going to consist of multiple individually screened twisted-pair wires, all combined in one insulated cable, something like the below, see attachment: "03_Cable_example.png"

I am intending to have each PCB fitted with two D-sub type receptacles, that way, the PCBs can simply be chained together with multiple-such short cables, fitted with compatible connectors at each end, see attachment: "04_Daisy_Chaining_Idea.png" These cables will probably not be much longer than 30cm each although there might be some exceptions.

The PCBs communicate with each other via CAN bus. But I am aware that this board-to-board connection strategy means a few cm of unscreened, untwisted CAN traces on each PCB – and there will be up to 7 PCBs. The question is: would this be enough to likely cause communication disruption in the electrically noisy environment of a DC motor-powered electric vehicle with 150 of amps of traction power flowing? I will do my best to keep the distance between the receptacles on each PCB as short as possible – would criss-crossing the CANH and CANL PCB traces over each other through alternating trace layers in an effort to mimic a twisted pair wire, be worth it?

I also expect there to be a fair bit of vibration so I am looking for a variant of D-sub that offers extra vibration resistance; can anybody recommend a good connector for this? It doesn’t really have to be D-sub, to be honest - I just like them.

TLDR: We are building a low-speed EV, and the control electronics consists of multiple PCBs. I want to simplify board to board connection as much as possible, ideally combining power supply and board-to-board comms into a single cable with individually screened twisted-pair wires eg: "03_Cable_example.png". But the board-to-board comms is mostly done over a CAN bus, and my daisy-chaining idea (see attachment: "04_Daisy_Chaining_Idea.png")  will unfortunately mean a few cm of unscreened/untwisted PCB traces for the CAN bus on each PCB – and there will likely be 7 PCBs total.

My questions are:
- Will the few cms of unshielded/untwisted traces on each PCB be likely to cause us CAN comms errors? Care will be taken to locate them as far away as possible from traction supply cables, the DC motor and the motor controller - but at this stage cannot guarantee exactly how far. If it could be a problem, could routing the CANH/CANL traces in a criss-cross pattern in alternating PCB layers (in an attempt to mimic a twisted-pair wire) help?
- Could there be other potential pitfalls to my board-to-board connection method that I haven't thought about?
- Can anybody recommend a rugged and simple connector for us to connect our boards together? I was intending to try and find a vibration-resistant variant of D-sub but I'm not sure. Ideally, we want it to be at least 8-way.

wasedadoc:
D-subs can have locking screws. Would they not stay together long enough?

Trotters_Independent2:
I'm aware that they do have locking screws, but I am honestly not sure - not because I think they aren't good but because I don't have experience dealing with vibration. I just want them to be vibration resistant enough so that we can connect them up and forget about them indefinitely.

In my head, I think that the locking screws could potentially work themselves loose and there ideally should be an alternate latch-based locking mechanism. I am not very "mechanically" minded, if I'm honest.

ch_scr:
Just put low-strength threadlocker (e.g. Loctite 222) on the threads - literally made to prevent them from backing out due to vibration, while still allowing easy removal.

moffy:
One problem with daisy chaining a CAN bus is that a single failure will bring down the entire bus. If possible, separate out non critical items and give them their own bus while keeping critical items separate.

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