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Unread 12-12-2011, 08:34
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JamesCH95 JamesCH95 is offline
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AKA: JCH
FRC #0095 (The Grasshoppers)
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Re: Tips on loosing weight (Not spam)

I have the mindset of making everything as light as possible before adding it to the robot. "Pounds are made of ounces" is one of my favorite mantras from building race cars that I have brought to robotics. That is, we try to lighten every part before it goes on the robot. The savings seem trivial at first, but they add up to be significant.

Some tricks:
-welding the kit frame saves ~3lbs of fasteners and blocks and eliminates loosening frame fasteners from your pit checklist
-plastic bearings are super-light and can replace metallic bearings in some applications
-using 25 series chain instead of 35 series chain drops a significant amount of weight, I would not consider this on the drivetrain except as a last resort though
-designing with an eye to keep wiring runs as short as possible not only reduces weight, but improves electrical system efficiency (consider making that beautiful wiring run a little more utilitarian)
-the new air compressor is around 2.6lbs lighter than the older compressor, that's huge (FWIW I aim to use pneumatics for at least 3 small functions or 2 big functions to consider them worth the weight)
-using high-grade fasteners can drop weight if they are selected properly
-consider eliminating redundant fasteners
-consider replacing low-load fasteners with zip-ties, plastic bolts, or velcro
-speed controlling through software rather than excessive gearing where possible, one encoder weighs a lot less than another sprocket and chain set or pair of gears

There is very rarely a weight-reducing trick that saves a huge amount of weight. In my opinion good light-weighting is accomplished through a systemic discipline of cutting ounces, or fractions of ounces, wherever possible.
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