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Topic: How to use arduino in rough enviorment ? (Read 919 times) previous topic - next topic

joer00

I am planning to use Arduino and RasberryPi for my old but rebuild 23.000 pounds wheel loader. The first part of the project is to add a display for all machine data like pressure and temperatures. I do have all sensors for this and it works in the "lab".

So now how can I put this on the machine which works in mud and rain with strong vibration while working ? I doubt I can use a closed case due to heat, but maybe I can with a big heat sink ?

Also the cables I use now to connect the pins will not survive a harsh environment. Are there any special plugs to connect the arduino pins to preferable a board which providers a a kind of loop tib terminal/cable clamp ?

spycatcher2k

The normal thing to do is create your own PCB, if you can't, the next best thing is learn to solder. There are lots of  shields with prototyping space on them, this makes it easier to attach wires permanently.
-=-
http://www.uk-pcb.co.uk - UK Based PCB Fab & Assembly Company
Design & Assembly work undertaken - Arduino repairs & testing - PM for details. Arduino & C# PC programming.

Sneak

#2
Nov 26, 2017, 09:25 pm Last Edit: Nov 26, 2017, 09:41 pm by Sneak
While I haven't ruggedized an arduino, I used to work in a telemetry company and have ruggedized bespoke integrated kit for use in hazardous + very rough conditions, and these few tips from past experience came to mind.

Potting: once your board is tested, put it in a small appropriately sized tray and fill with potting epoxy. for bench prototyping, at a pinch you can use candle wax (but *NOT* for field, heat can cause wax to vaporize and become fire risk). pro tip: remember that the viscosity of your potting compound changes with local ambient temperature, so always test one board before doing a batch or you may wreck a lot of kit (epoxy will either not fill into all areas, or will be too thin and seep into connectors)

Cable bleed: both sides of cable shielding must be properly sealed. liquids seep through cable shielding and can cause big problems.

Enclosure: If heat is an issue usually using a metal finned enclosure for the device will wick away enough heat. If power usage is no issue, you can use a TEC to assist. When sealing, always use the right kind of sealant, some sealants release vapor that will corrode copper over time. Also, use marine-grade screws in field if you don't want to have to use a drill to re-open it later.

Connectors: we had a lot of joy with the Bulgin Buccaneer range. They aren't perfect in high pressure rapidly changing temperature environment though, we had to pot them after installation for best results.


larryd

Pot the whole thing into a big lump of silicone glue.


No technical PMs.
The last thing you did is where you should start looking.

CrossRoads

#4
Nov 26, 2017, 10:11 pm Last Edit: Nov 26, 2017, 10:12 pm by CrossRoads
I made boards with db15 connector and thermally conductive 2-part epoxy.  We did a lot of boards, had bigger bottles:
https://www.digikey.com/product-detail/en/mg-chemicals/832TC-450ML/473-1089-ND/655660
Needed 2 hour bake in a low temp oven to cure it, or wait a really long time.  Maybe we hadn't stirred both parts well enough before mixing together and pouring into a mold with the card.  We were doing 12 at a time in square muffin pans.

Selected all high temperature range parts, including the 328, rated to 105C or higher
https://www.digikey.com/products/en/integrated-circuits-ics/embedded-microcontrollers/685?k=atmega328&k=&pkeyword=atmega328&pv252=774&FV=ffe002ad&mnonly=0&ColumnSort=0&page=1&stock=1&quantity=0&ptm=0&fid=0&pageSize=25
Had to seal around the bottom of the connector with bead of silicon before potting to keep the potting from seeping up into the bottom of the connector.  Learned that the hard way.

Can go higher temp on the 328, may have to wait longer to get them
https://www.digikey.com/product-detail/en/microchip-technology/ATMEGA328P-15MZ/1611-ATMEGA328P-15MZCT-ND/6832161

Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

joer00

Awesome, thanks for your suggestions,  will test it out :)

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