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Unread 30-05-2014, 13:29
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Re: Weight Saving Techniques

Quote:
Originally Posted by Kevin Leonard View Post
I put together a presentation for my team last year on how to build robots for reliability.
I won't go into it extensively, but my essential point was there are two components to reliability on a robot- durability and maintainability.
The robot needs to be durable enough to survive matches, and mechanisms need to be able to be replaced or maintained in order to keep the robot in peak condition.
Things like the frame of the robot aren't replaceable- and thus mostly not maintainable, so they need to be extra durable.

I'm not saying not to use thin-walled aluminum, because that would be ridiculous. But remember the trade-offs you make when you make parts out of certain materials. Do the math, then add a little safety factor. You might thank yourself later.
I'd be really interested in seeing a white paper on this document-- often I see teams with few engineeringg mentors/less experience with major reliability problems that probably could have been avoided.

Back to the topic, planning in your lightening is definitely the way to go-- if you can lighten a part without sacrificing functionality (ie in a chassis- 1/8" box tube is totally overbuilding and can in almost all cases be lightened), plan it in and drill your lightening holes before assembly. Just transfering to doing this saved my team from almost all our previous weight problems for the past few years.

Outside of that, using fasteners intelligently (as previously mentioned) is also huge. You DO NOT need screws and nuts in a lot of the cases I see them-- properly sized rivets, welding, or even using washers can save you a ton of pain, both in weight and maintenance.
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